CO₂ level is high enough that it reduces cognitive ability. Isn't that a reason to worry?

There looks like legitimate cause for further study, preferably by scientists breathing air under 950 ppm $\small\mathsf{CO_2}$ (this study showing a 15% decline in cognitive ability at this level).

Because it is not known what mechanisms are involved in this decline in cognitive ability it is not clear if there are threshold levels, with step changes in impacts or if the effect is linear, but changes at below 950 ppm is indicated and subtle impacts at much lower level seem likely, with one leading expert (Vivian Loftness) on Health, Productivity, and the Quality of the Built Environment suggesting atmospheric levels above 600 ppm would be cause for concern about cognitive effects. For people with poor cognitive abilities potential impacts of $\small\mathsf{CO_2}$ levels is not known, but could be significant - this, along with impacts more generally at levels that are within the range of possible $\small\mathsf{CO_2}$ concentrations people now living can expect outdoors needs more study.

The principle response in the near term is improving air quality in buildings, with raised atmospheric $\small\mathsf{CO_2}$ levels most significant with respect to rates of $\small\mathsf{CO_2}$ buildup and the required air replacement by ventilation systems. There are ample reasons to commit to actions that reduce emissions and $\small\mathsf{CO_2}$ rise in the atmosphere, but better understanding of all the potential consequences is worthwhile.


Yes, the Appalachian Region would be considered a Temperate Rainforest based on a combination of rainfall numbers, humidity and temperatures. Its latitude runs from in the 30's and up to high 50's in latitude location north of the equator. Feeding the forest region are a combination of two damp air masses which rotate in a cyclonic rotation inward from the marine locations, namely the Maritime Tropical air mass bringing very humid air from the Gulf of Mexico and the cooler air but also damp Martime Polar air mass. The mountains, while lower in elevation than the Western Rocky Mountains, offer much of this damp air from either air mass to move over toward the mountains when the jetstream is positioned in a way to not influence these air masses in a way that pushes them eastward. Orographic type precipitation can occur as a result, but much of it in that region is frontal as the colder Contintental Polar and Arctic air masses tend to interact with the damp air masses mentioned previously dumping significant amounts of rainfall suddenly as I can attest in my many journeys through these mountains on my way to Georgia or Florida from Ontario. Given the rainfall alone and the fact there is a diverse complexity of vegetation and animal specie, I would surely believe that the Appalachian Region qualifies easily as a Temperate Rainforest. Climate graph > location in Appalachian Region https://en.climate-data.org/north-america/united-states-of-america/virginia/appalachia-135846/#climate-table  and, location map of North American air masses paths running along and to this region https://wordpress.accuweather.com/wp-content/uploads/2018/01/static-winter-air-masses-11-am-1.jpg?w=632


Noctilucent clouds and anthropogenic climate change

The current answer is uncertain, especially with recent observations.

Zahn (2003) outlined that despite the possibility of noctilucent clouds (NLC) being sensitive to water vapour mixing ratios and temperature, there are 3 main concerns as to the link between the frequency of NLC occurrences and climate change:

NLC observations have shown a great variability (including in frequency) since they were first described in 1885.
There has been no significant variation in altitude
The timeframe of observing this phenomena is too short to fully delineate natural and anthropogenic forcings.

In 2007, the AIM (Aeronomy of Ice in the Mesosphere) mission was launched to explore NLC and related phenomena, in particular, the SOFIE (Solar Occultation for Ice Experiment) instrument.

In recent observations, reported in the NASA article Unexpected teleconnections in noctilucent clouds in 2014 found that the winter air temperature over the USA and Arctic stratospheric conditions have a direct link to the frequency of NLC over Antarctica (as per the image below from NASA):

Note: PMC is often used synonymously with NLC

This suggests that changes in winter temperatures on the opposing hemisphere may indeed alter the frequency of NLC occurrences.

However, other influences are being investigated, such as solar cycles, observations and research from the CAWSES II Climate and Weather of the Sun-Earth System mission have found that there appears to be a correlation between NLC frequency and solar flux, as seen in the graph below:

Image source: Project 3 PMC/NLC altitude, frequency and brightness changes related to changes in dynamics and chemical composition (Thomas et al.).

This all ties in with Zahn's 3rd doubt - more data from multiple observations are needed in order to fully determine whether or not the frequency of NLC has any relationship with climate change.

Reference

Zahn, 2003, Are Noctilucent Clouds
a "Miner's Canary" for
Global Change? EOS


This is arguably a theological rather than science-based issue, but since it is cross-cutting I will answer it. No, there is no possible mechanism for the sun to cease shining for three hours, but neither is there any such imperative implied in the original Greek text, which requires only a relative darkening of the sun. You are correct is recognizing that this was no eclipse. It may be noted that comparable 'darkness' is implied in other Biblical accounts, such as in Exodus, Joshua and Amos. Nowhere in these four texts is total darkness either stated or implied, but naturalistic explanations (i.e. scientific) - which in no way detract from the spiritual intent of the text - may be eminently applied to correct textural understanding.

As in so many modern misunderstandings, the apparent conflict between science and Biblical theology entirely disappears when the Bible is read sensibly from the appropriate perspective. The Bible is not a modern Greco-Roman literalist quasi-scientific text, and it is absurd to treat it as such. the Bible is basically a spiritually-inspired collection of 2000 to 3000 year-old Hebrew texts, written in the parabolic allegory-rich idiom of ancient Jewish culture. For all that, it is no less accurate in spiritual wisdom - but radically different from the 21st century world views.
Not only is it literature from a different culture, we also don't have any of the original texts! You are arguing on the basis of a modern British translation of a Greek translation of presumed Aramaic literature, which itself may have undergone several cycles of editing (as in the Noah story, which has at least four cycles of precursor literature).  Subtleties of meaning are lost in each stage of translation, so before drawing over-literal assumptions, first at least check the nuances of the earliest Greek translation. Had you done that, the question of absolute darkness would not have arisen, and partial darkness would more than adequately have proved correct - such as a sandstorm (as 'A child of God' suggested) or a super-cell storm cloud - which does occasionally occur in the Israeli highlands. Such superstorm events may indeed seem to be like night if they occur only minutes after the intense bright Mediterranean sunlight of the Jerusalem highlands.

Many Christians get hot under the collar when scientific explanations are applied to miracles such as this. It need not be so. It is not a case of "look at God doing the impossible, again", but of placing due emphasis upon the true miracle, which is the exquisite timing of the event in support of God's unfolding plan.


"steep slope" when cold fronts encounter warm fronts: Confusing sentence in textbook

The slope is the ratio of the vertical to horizontal distance.

From here

  "Warm fronts have a gentler slope and generally move more slowly than cold fronts, so the rising motion along warm fronts is much more gradual."

You can see the steep slope of a cold front visualized,

and a more gradual slope for the warm front:

But depending on the source, there seems to be varying definitions of what the slope value actually is.  It makes sense, given that the answer would be different depending on how deep you go into the front and there would be seasonal variability.

This site has a nice example:

  "The cold front is steepest in the lowest several hundred meters of the atmosphere with a slope of about 1/100, meaning that elevation increases about 1 kilometer for every 100 kilometers of horizontal distance from the surface front. Then the upward slant relaxes into a much more gentle slope (e.g. 1/300). All along the upward slant of the cold wedge, cold air abuts with warmer air, creating an upward-slanting boundary characterized by large temperature contrasts."


The ERA Interim reanalysis is made by ECMWF and the other reanalysis is made by NOAA. Reanalyzes of the past are made by running global climate models and these differ because NOAA and ECMWF use different models and perhaps even slightly different data. The models on the other hand can be very different for example on implementation of data assimilation, parametrization and even grid cell size.

All of these variables are vertically integrated. The ERA variables in the order you mention them contain:

-Total column water: all water

-Total column rain water: all liquid and solid water in droplets large enough not to be considered cloud droplets (my guess)

-Total column water vapor: all gas phase water

-Total column cloud liquid water: all liquid cloud water

The NOAA variables:

-Cloud water content: all liquid and solid cloud water

-Precipitable water content corresponds to Total column water

From these the Total column water vapor corresponds the Vertically integrated specific moisture. None of these is the divergence of the total column water vapor phase that you need. Although the paper you are referring approximates precipitation from moisture divergence, you could use just the Total column rain water and no approximation is needed (I didn't read the paper so I don't know if this is makes sense).

Edit, added sources:
The ERA variable list can be found here and you can search variables there and press them to get the definitions too. For NOAA I couldn't find a source for the definitions of these variables. If someone finds please edit this answer


Creating a drought metric using precipitation data?

One of the most widely used index to quantify the drought events is the standardized precipitation index (SPI) and it is actually based on precipitation time series only.
The index is used, among others, also by the NOAA.

I'll borrow the description of the index from a scientific article (Farinosi et al 2018)

  Standardized precipitation Index (McKee et al., 1993)

  The index is a measure expressed in standard deviation units of the
  variation of the precipitation of a specific number of months respect
  to the long run average (WMO, 2012). The number of months based on
  which the SPI could be calculated usually varies between 3 and 48
  months. Shorter time scales SPI is considered a good indicator of
  variations of soil moisture, while on longer scales (up to 24 months),
  it could be associated with groundwater or reservoir levels variation
  (WMO, 2012). That for, a shorter SPI (3 months) is often utilized to
  detect meteorological droughts; a medium SPI (6 months) is usually
  associated with agricultural droughts; a longer SPI (12–24 months) is
  associated with hydrological droughts. SPI was calculated using the R
  package SPEI (Beguería and Vicente-Serrano, 2014).

Usually the minimum requirements to have a robust estimation of the SPI is to have a precipitation time series of at least 30 years.

You could use the SPI to quantify the number of "droughts" (choosing a threshold under which you define the event - for instance see this) in a period for your area of interest and then aggregate the number of "meteorological", "agricultural", and "hydrological" droughts.


Transform Boundary and its relation with Earth's rotation

NCERT is an Indian document written from the perspective of the prevailing non-scientific educational culture, in which (for example) astrology is considered to be bona-fide science! Therefore it is not authoritative, and certainly not written accurately from the perspective of peer-reviewed scientific sources. It has been criticized before, and in this case it is quite incorrect to write that transform faults are significantly affected by the Earth's rotation. Rather, the NCERT quotation that you cite seems to confuse the Earth's pole of rotation with the Euler pole of rotation. The latter is a key concept of the plate tectonic movement between any two plates. The Euler pole of rotation can be at any angle with respect to the Earth's rotational axis.


Nitrogen cycle semantics; nitrification/nitrogen fixation

I went to do a bit of research on this, and think that you can get a satisfactory answer just from the relevant wikipedia articles. Here are some select quotes:

Nitrogen fixation is a process by which nitrogen in the Earth's
atmosphere is converted into ammonia (NH3) or other molecules
available to living organisms.

Nitrogen fixation has the chemical process:

N$_2$ + 8 H$^+$ + 8 e$^−$ $\rightarrow$ 2 NH$_3$ + H$_2$

and is performed by Diazotroph bacteria or archaea. Some of these are symbiotic with plant roots, especially of the family Fabaceae.

Nitrification is the biological oxidation of ammonia or ammonium to
nitrite followed by the oxidation of the nitrite to nitrate.

An example of a nitrification chemical reaction is:

2NH$_4^+$ +  3O$_2$ $\rightarrow$ 2NO$_2^−$ + 2 H$_2$O + 4 H$^+$
2NO$_2^−$ + O$_2$ $\rightarrow$ 2 NO$_3^−$

There are a wide variety of bacteria that peform these steps, and some only do one step or the other. There are also other pathways for reducing ammonia instead of ammonium, for example.
In conclusion, these are two different biologically driven steps in the nitrogen cycle, driven by two different sets of microorganims. There other biologically driven processes as well, such as ammonification, where organic nitrogen compounds in formerly living tissue (or waste) is broken down into ammonia or ammonium.


After days of smoky air, why is it healthier to stay inside?

If you're in the open air you will be exposed to the full concentration of the pollutants in the air. By being inside, there's a reasonable assumption that the rate of interchange of air between inside a house and outside will be low and that inside there will be a lower concentration of pollutants.

Houses and buildings are not hermetically sealed. The gaps around windows and doors are small which results in low rate of airflow between the outside and inside of the houses and buildings. The less windy the weather the lower the flow rates.

The other way to consider it is when a room has been closed for a lengthy period while someone has been in the room, the air in the room becomes stuffy. This is because the air in the room is not being replaced by fresh air quickly enough to remove stuffy air. To remove to stuffy air the windows and doors need to be left open for a period of time for fresh air to replace the stuffy air.

The same thing happens when the air outside is heavily polluted. The air inside is cleaner and remains cleaner for a longer period if the doors and windows remain shut because the rate of transfer between air inside the building and outside is small.


Why is ozone a greenhouse gas if it absorb UV radiation?

Ozone is indeed a greenhouse gas. But not due to its capacity to absorb/scatter UV radiation, but instead due to its capacity to absorb infrared radiation. In contrast with other greenhouse gases (Like $CO_2$ or Methane), the spectral absorption bands of Ozone are not confined to the infrared part of the spectrum, there are ozone absorption bands also the UV too.
However, if ozone were capable to absorb only UV radiation, it would NOT be a greenhouse gas. Because the Earth's surface do not emit UV radiation.

Therefore, the greenhouse gas properties of Ozone do not come from its ultraviolet absorption bands, but instead from its infrared absorption bands, that you can see in the following infrared spectrum obtained from NIST:


What types of high-level mathematics are useful in doing climate modelling/meteorology?

The question may generate primarily opinion based answers but while it is open one would like to present the following information.

At the outset most of the people I know in the field work in NWP and the reason people avoid higher mathematics(by that I mean looking for analytical solutions or pure math based projects such as you mention topology or Riemannian geometry) is because of the issue of jobs after completion of their respective Ph.ds and post docs. More of the recent advances use approaches from statistics and Big Data and that is because of the massive amounts of data that is available on a daily basis.

Presuming one wants to move on a "path" in academia then there is this application of topology in meteorology - Hairy ball theorem  and this book should provide more information on the topic An Introduction to the Geometry and Topology of Fluid Flows but applications of the material in the book to actual problems in meteorology may be few in so far as I am aware and others can perhaps provide better information. This workshop Complex Analysis And Geometry does provide some applications of differential geometry to meteorology but these I reckon are most of the outlier groups and most of the work is on improving skill of NWP models.

A colleague of mine in academia works on Potential Vorticity and Slow manifolds which is a part of Stability theory and fast manifolds/inertial manifolds. Essentially one is looking for a point after which the flow becomes unstable and why is that ? That is because unstable flows can be ultimately linked to weather forecasting and NWP models. There is the famous paper by Edward Lorenz that reviews that topic - The slow manifold what is it ?

While it is numerical work I  and many others use Vector Spherical Harmonics  because we all deal with global circulation models(spectral method) and others use wavelets to analyze equatorial waves

Finally there is this paper by Tapio Schneider that mentions Gauge transformations


Where to start searching to find more radioactive minerals?

You can try using the locality list at MinDat. Go to places that are easily accessible to you and see what minerals have been reported there. If there's something radioactive, it will probably be listed there.

I would remind you that radioactive minerals are, well, radioactive. These things are dangerous. I strongly recommend you find a different hobby. I deal with radioactive minerals as part of my job, and this is not something that you want to do unless you really know what you're doing. I remind you that a lot of the early researchers who worked on radioactivity died because they did not use the necessary precautions.


Are there any geology only related educational institutions?

Why would you limit yourself? You could just go to a regular university and enroll in the geology degree program. In some countries (like Germany) you would then only take courses necessary to become a geologist (including the math and physics you need to understand for it). In some other countries (e.g, the United States) you'd have to take other courses for "breadth requirements" as well, but most of your courses would still be in geology.

The fact that a regular university also offers courses in other areas doesn't really matter that much, or does it?


Presence of Diabatic heating term in the continuity equation

In the book - Atmosphere-Ocean Dynamics, Volume 30  the author AE Gill defines the perturbation pressure in the paper that OP references as the following.

Consider a pressure of a reference system (ocean/atmosphere at rest) and let us call it
    $$p_0$$.

It must be noted that a real atmosphere is never at rest and so we consider deviations from the reference system.

Since we are dealing with a vertical pressure gradient for OP's equation(2.5)(the gravitational force matches the vertical pressure gradient for hydrostatic large scale circulations)

$$p_0$$ is a function of $z$ where z is the height coordinate.

Then the perturbation pressure $p'$ is defined in the following way

$$p = p_0(z) + p' $$

So if you add the perturbation pressure to the reference pressure we get the deviation from the reference system.

Similarly a perturbation density can be defined in the following way

$$\rho = \rho_0(z) + \rho' $$

The basis for doing this comes from classical mechanics Perturbation Theory

The question is why is this being done ?

We are looking for solutions that are basically of a oscillatory nature. So in effect this gets rid of the non linear cross terms for which no oscillatory solution exists.

In the specific case of 2.5 from the paper you referenced in addition to the Brunt–Väisälä frequency one needs to consider a "buoyancy forcing" especially in the tropics because of the large contributions from diabatic heating. We are essentially talking of an "open system" where in addition to adiabatic "work" being done you also have to account for heat exchange between a system and the ambient environment. In reality this is assumed as "pseudoadiabatic" process

Then the question is how is the heating rate modeled ? In the AE Gill book this is given by the following equation

$$ Q_H =  -L_V \frac{Dq_w}{Dt}$$

where $L_v$ is the latent heat of vaporization and $q_w$ is the saturation humidity where the word saturation means the saturation water vapor mixing ratios.

Equation (2.5) from OP's paper is derived in Gill's book and is present in the 9th chapter(9.13.7) and will not be derived here but will be stated as is

$$\omega_n = \frac{\partial \widetilde \eta}{\partial t} + \widetilde b_n$$

Here $\widetilde \eta $ is the vertical coordinate(in OP's paper the vertical coordinate is pressure) and $b_n$ is the rate of change of buoyancy  per unit volume. This form is known as the buoyancy forced Shallow water equations

One can get more details about the perturbation theory for the atmosphere by looking at this link - Atmospheric Oscillations: Linear Perturbation Theory

Similarly if you want horizontal pressure perturbations you model the reference pressure as a function of x and y and then consider deviations thereof.

Useful reading
What is the meaning of pressure in the Navier-Stokes equation?


At the same speed, is a tornado as dangerous as straight wind?

I'd have to say a tornado would be more dangerous than a straight wind of equal speed. Tornados have a very low-pressure center and violent updrafts as can be seen in this YouTube video . As the roofs are blown off you'll notice they get blown upward as well as sideways.


Curved trees are a sure sign of movement of surface. Special geomorphic shapes are also present in a slowly developing landslide. At the top of the landslide cracks can start to show, at the foot you can find "bumps" in the soil. Water will have difficulties to drain at the foot of the landslide.

Here are a few examples of literature that should be something to start with:

http://ny.water.usgs.gov/pubs/jrn/ny0155/jrn02-r20500g.pdf
http://www.ags-hk.org/notes/09/Geomorphology_and_Landslide_Hazard_Models_Steve_Parry.pdf
http://www.adpc.net/casita/pdf/01-Geomorphic-mapping.pdf


What could have formed the pattern inside this piece of siltstone?

Interesting. The photo is low quality so I can not say for sure but possible candidate explanations are:

a septarian concretion
a fulgorite
a dendrite
a differential staining based on differences in porosity

To get a better answer please include some close-ups of the central area and some pictures of the other sides of the rock


Why is the part of the earth tilted towards the sun warmer? Which factors matter more?

The 5 factors you mention are not nearly as important to the effect you're asking about as another, more fundamental factor: time.

If you've read my answer to this other question, you should understand that all of the factors you mention would create temperature differences at different latitudes whether the Earth is tilted on its axis or not.

But because the Earth's axis is tilted, at some parts of the year the regions of the Earth tilted towards the Sun (in "summer") receive sunlight a greater proportion of the day than the regions pointed away (in "winter").

Not only that, because of the more direct angle of the Sun the factors you list mean that the regions in "summer" are heated better during the day than the regions in "winter".
And this adds up over all the days of summer or winter until the Earth's orbit reorients the axis relative to the Sun.

Or even more succinctly, summer is hotter because the Sun is higher in the sky for more of the day.


Are strong deep earthquakes that result in minimal impacts common?

Depends where you are in the world, New Zealand has a combination of deep the shallow earthquakes, the shallow ones are associated with the slip-strike faults in the south. The deeper ones on the other hand occur where subduction is the dominant tectonic scheme in the north island, particularly in central and eastern areas. A deep earthquake of a given magnitude will cause considerably less damage to human artifacts than a shallow one; there's more, and softer, rock between the rupture zone and the surface to absorb the energy of the 'quake. If they're deep enough then the hot, plastic, rocks between the rupture and the surface will in fact block most of the L and R shear waves that often cause the most surface damage.


Where to get temperature sounding model forecast data?

The GSD file is just a text (ASCII) file, which you can read with almost anything you want. Since you are using python I would recommend looking at Pandas and especially the pandas.read_csv functionality.

I am using this URL as an example now:
https://rucsoundings.noaa.gov/get_soundings.cgi?data_source=Op40&latest=latest&start_year=2019&start_month_name=Dec&start_mday=3&start_hour=7&start_min=0&n_hrs=1.0&fcst_len=shortest&airport=50%2C-90&text=Ascii%20text%20%28GSD%20format%29&hydrometeors=false&start=latest

From the ruc soundings you referred to. Here I just entered lat=50 and lon=-90 to pick something. You see this in the URL in "airport=".
You can download the data you need with wget or curl and put into a file with a better name (sounding.txt) like this:

wget "https://rucsoundings.noaa.gov/get_soundings.cgi?data_source=Op40&latest=latest&start_year=2019&start_month_name=Dec&start_mday=3&start_hour=7&start_min=0&n_hrs=1.0&fcst_len=shortest&airport=50%2C-90&text=Ascii%20text%20%28GSD%20format%29&hydrometeors=false&start=latest" -O sounding.txt

Then you can write a small python program to fetch the data you need and read the data with pandas.

I also want to note that if you are going to use grib2 you will be able to easily change the model since grib2 is a standard format for NWP data. This will be a little more complicated, as it is a bit more tricky to read. grib2 is a binary format that is very good for storing large datasets. I refer to eccodes from ECMWF if you want to look more into this.


What are the causes of the supercontinent cycle?

Please take into consideration that I am not a specialist of plate tectonics, just a paleontologist.

Although this cycle is often nicknamed the Wilson cycle (probably because of Wilson, 1966), the idea that supercontinent formed cyclically every 440Ma was advanced by Worsley et al. 1984 (see review on the subject by Nance & Murphy 2013).
The mechanism they hypothesize for the breakup of the supercontinent is the mantle heat flow accumulating below the supercontinent while the formation of the supercontinents are bound by the cooling effect on the density of the oceanic lithosphere (see also Nance et al. 1988): so basically, heat accumulate below the insulating supercontinent until it causes it to break up, thus creating rifts and a new oceanic lithosphere, which, with age, cool down and thus become more dense making it more prone to be subducted by the continents (if I understood correctly).
As to "why ca. 450 Ma?" this has probably to do with the cooling speed of the oceanic lithosphere, I would assume.
Another important point: although there are evidences for the existence of a supercontinent breaking-up at 300 Ma (Pangaea), at 750 Ma (Rodinia), at 1.6 Ga (Nuna or Columbia), etc., there are also evidences for an absence of supercontinent at 1.2 Ga (see Pisarevsky et al. 2014), hinting that this cycle is maybe not that regular.

References:
Nance & Murphy, 2013. Origins of the Supercontinent Cycle. Geoscience Frontiers, 4(4): 439-448.
Nance, Worsley & Moody, 1988. The Supercontinent Cycle. Scientific American, 259: 72-79.
Pisarevsky, Wingate, Li, Wang, Tohver & Kirkland, 2014. Age and paleomagnetism of the 1210 Ma Gnowangerup–Fraser dyke swarm, Western Australia, and implications for late Mesoproterozoic paleogeography. Precambrian Research, 246: 1-15.
Wilson, 1966. Did the Atlantic close and then re-open?. Nature, 211: 676-681.
Worsley, Nance & Moody, 1984. Global Tectonics and Eustasy for the past 2 billion years. Marine Geology, 58: 373-400.


Bones don't last very long in jungles. Or in forests. Or almost anywhere.

Fossils are the consequence of one highly unlikely fluke after another. Darwin himself commented on this. It takes just-right circumstances to have the bones of a recently deceased animal not be eaten by scavengers or turned into rot by bacteria. It takes yet another set of just-right circumstances for those bones to turn into fossils. It takes yet another set of just-right circumstances for those fossils to be brought back to surface level. It takes yet one more set of just-right circumstances for those nearly exposed fossils to survive the ravages of time and weathering.

The last coincidence is where deserts come into play. Water is an extremely powerful weathering agent. The key characteristic of deserts is an extreme lack of water. Fossils are much more likely to survive the savages of time without that weathering by water.


In hydraulic fracturing, can total oil/gas production be broken down by stage?

Don't bother trying to isolate production by stage unless you have a production survey.  Even then it is often irrelevant as the chance of restimulating the specific rock that is lower producing is small.


Bifurcation is relevant to the atmosphere because it effects the predictability of the evolution of the atmosphere.  I can't speak to its merits with climate models, but with weather it is quite important.  As Lorenz discovered, the atmosphere is chaotic and numerical prediction is very sensitive to the initial conditions.  If the initial conditions are close to the bifurcation point, the solution can be wildly different and this leads to poor predictability.

In particular, weather models assimilate observations and each observation is a value and an uncertainty.  When the uncertainty contains the bifurcation point that essentially means for that particular scenario the instrument error is such that the instrument can provide an observation on either side of the bifurcation. This can be explored with ensemble modeling where many models are run with slightly different initial conditions (or slightly different models, or both) and leads to a large spread in the ensemble and low confidence in the forecast.  Our atmosphere can be more sensitive than the instruments we use to measure it can detect.

I'll try to dig up some references to presentations I've seen that show hurricane dissapation / rapid strengthening determined by differences in gulf of Mexico observations smaller than the instrument error reporting them.  For more NWP-centric studies, you can search for articles on predictability.  I know there should be a couple by Dr. Fuqing Zhang (PSU) and I'll edit when I can point to some specific articles.


Is there a list of instances where mountains that have been mined out of existence?

Of course it happens elsewhere! However, I'm not sure there's a specific term, generally. Even in the "montaintop removal" country of Appalachia, there is no more prosaic term for the practice other than MTR. Too bad! It surely deserves a better term!

And...despite the complete excising of an entire mountain within the Oquirh mountains, even the Salt Lake City population has no term for Complete Mountain Removal!


Will the Mini Ice Age solve our Global Warming Heat problem

I'm going to try to answer this, though it's actually a very hard question depending on how close you look at it.

Lets start with the American Physical Society's statement on climate change - which, they've made an effort to balance out following their 2007 statement of "evidence is incontrovertible" that got some members upset and lead to a handful of high profile resignations.    More on that here

This is their more balanced statement.

http://www.aps.org/policy/reports/popa-reports/energy/climate.cfm

  The relationships between the atmospheric concentration of greenhouse
  gases and their radiative effects are well quantified. Forcing from
  the long-lived greenhouse gases: carbon dioxide, methane, and nitrous
  oxide, is presently about 2.5 Watts per meter squared (W/m2). Of this
  total, 1.6 W/m2 is from carbon dioxide alone. The total anthropogenic
  forcing is uncertain, particularly because the magnitude of the
  negative forcing associated with sulfate aerosols is unclear. While
  changes in solar irradiance may have affected global climate in the
  last century, a 0.15% change irradiance, the order of estimated
  changes, results in only a 0.36 W/m2 forcing.

and, numbers vary, but this seemed a pretty fair article on Solar Irradiance:   http://earthobservatory.nasa.gov/Features/SORCE/sorce_03.php

It says:

  The number of sunspots visible from the Earth not only changes from
  day to day, but also in cycles that can last from decades to centuries
  to millennia. The most well-known and well-analyzed of these cycles is
  the 11-year sunspot cycle. Over the course of 11 years, the yearly
  average number of sunspots and faculae slowly increases and then
  return to normal levels before rising again for the subsequent cycle.
  The change in the Sun’s yearly average total irradiance during an
  11-year cycle is on the order of 0.1 percent or 1.4 watts per square
  meter.

So, 1.6 watts per square meter from Co2 (2.5 watts total) and (up to) 1.4 watts per square meter low to peak solar irradiance, but there's a problem with that 1.4 number.    It's low to high, meaning low to average is 0.7 watts per square meter and that's how we should measure assuming the sun enters a grand minimum, we should measure against the average, so the real number is 0.7 watts per square meter drop - assuming the study is right and the sun does enter a new Maunder Minimum.

Skeptical Science posts a similar number:

Source:  https://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm

The variation in their chart appears to be similar to the 0.7 variation we should expect from the NASA article, average to low range.

There's also the, all but guarantee that CO2 will continue to rise, at least, for several more years, so the APS estimate is likely to go up.   Also, the APS number doesn't include feedback mechanisms - and they say as much in the article linked above:

  The largest source of uncertainty lies in determining the magnitude of
  climate feedbacks. For example, an increase in trapped radiation and
  the associated warming is expected to increase the level of water
  vapor in the atmosphere, which would tend to further enhance the
  greenhouse effect ó a positive feedback. An example of a negative
  feedback would be an increase in clouds that reflected more sunlight
  back into space. The actual feedback from changes in clouds is
  uncertain since they also act to trap outgoing infrared radiation.

Now, the positive feedback from water vapor is a given and the negative feedback from clouds is more uncertain, so I think the APS article is a little bit more friendly to the skeptics than the actual science (IMHO).  Clouds reflect sunlight, but clouds also trap heat at night.  The total cloud effect is, well, a little more cloudy than APS' one line suggests.

Skeptical Science has an article on cloud feedback here:  http://www.skepticalscience.com/clouds-negative-feedback.htm

So, where does that leave us:

Well, first, the study that the sun is going to enter a grand minimum in the next few decades needs to be verified, lets start there.   A whole bunch of bad science has been published by those trying to disprove, discredit or cast doubt on climate change - so skeptisism of new studies first, especially on this topic, but, lets say they're right - which was the original question.   Would that be sufficient to stop man made global warming?

No.   I think it's pretty likely it would be insufficient.   0.7 is less than 2.5.   But, if they're right, it's still kind of good news, cause it would soften the blow - and that's a good thing.   I hope they are right.   But the sun's maximums and minimums have a pretty small effect on climate change.  Maybe a degree here or there.   Man made climate change should be 2 degrees by the end of the century, and perhaps more if left unaddressed in centuries that follow.

As Steve Emmerson points out, the effect of the Maunder Minimum isn't 100% accepted as the sole cause of the Mini ice age.   There's still some unknowns, but I feel, with pretty high confidence, that the sun entering a new grand minimum would be insufficient to stop the warming, but it might slow it down, a little.

Too long?   I can try to clean it up a bit later.


Yes, high flying jets can damage the ozone layer, but the consensus of opinion is that at present this damage is trivial and nothing to worry about. If, on the other hand, Concorde-type supersonic transports were to become commonplace, it might be another matter. It was found that Concorde's engines produced much more sulphuric acid particles than the exhausts of subsonic aircraft, and it was this sulphuric acid that damaged the ozone layer. Whether or not enough supersonic military aircraft fly at the relevant altitude and cause significant damage is something nobody seems to know, but probably not. The jets need to fly at altitudes between about 30,000 feet and 45,000 feet to cause ozone damage.


Is it feasible to 'harvest' the clathrates from the permafrost before they evaporate?

No, it's not feasible. They are too dispersed, and any operation to harvest them would be too costly and inefficient, and would amount to vandalism on a gigantic scale. We just have to hope that the vast majority of tundra clathrates will remain un-melted, as will probably be the case. The last time they were melted on a massive scale may well have been the Permo-Triassic extinction event of 250 million years ago.The Arctic tundra is a vast natural wilderness full of valuable wildlife. Any ill-judged operation to remove clathrates would not only be grossly expensive and inefficient, but would have both taxpayers and environmentalists up in arms!

Assuming theories of the Permo-Triassic event are correct, it took the long term eruptions of the Siberian Traps super-volcano to release almost unimaginable quantities of CO2 into the air to trigger the melting of clathrates. Eruptions of super-volcanoes like the Siberian Traps 250 million years ago and the Deccan Traps 66 million years ago make modern volcanic eruptions, even Krakatoa (1883) or Tambora (1815), pale into insignificance.


What can one come to know about a mineral just by knowing name

It depends, most of the mineral names we use are derived from old Greek names that were basically comments on the appearance or behaviour of the materials so Galena means literally Lead Ore, which it is, Cassiterite is an ancient word for tin, which it is still be main ore of up to the modern day. On the other hand Pyrite means on fire due to its ancient use as a spark source and Hematite simply means blood and is a comment on the colour of certain European deposits. So if you brush up on your Greek you can tell some things about some minerals but others will remain quite opaque.


How does the meridional overturning circulation affect sedimentation rates in the North Atlantic?

Downwelling speeds in the deep water formation areas are likely not significant when compared with the settling speeds of most sediment particles. While deep waters have clearly defined oxygen and nutrient characteristics, it does not seem likely that they can have a particular sedimentary character.

The deep water circulation associated with the meridional overturning circulation (MOC), while not very intense (a few cm/s), can transport some of the finer sediment classes along with it.

The main sedimentary signal is likely associated with calcium carbonate. The shutdown of the MOC could have significant effects on the CaCO3 balance (Chikamoto et al., 2008).


How much of arctic ice is from snow fall versus frozen sea water?

I'm assuming this question is asking about the sea ice in the Arctic Ocean as opposed to ice caps such as that over Greenland. The sea ice on the Arctic Ocean is predominantly (overwhelmingly!) frozen ocean water.

The Arctic Ocean loses 17 to 18 thousand cubic kilometers of ice every summer, only to regain most of that melted ice during the long Arctic winter when the ocean freezes at the surface. That corresponds to a layer of ice well over a meter thick that melts and reforms every year.

The Arctic is a desert, and an extreme desert during the Arctic winter. At 40 below zero (Fahrenheit or Celsius), it's simply too cold to snow. The amount of precipitation that falls on the Arctic Basin over the six to seven months or so when the ocean freezes is about a tenth of a meter.  Snowfall cannot account for anywhere close to the meter+ thick layer of ice that forms during the Arctic winter. The tiny amount of snow that falls during the Arctic winter can't accumulate the way it does over ice caps.

Compare with Antarctica. Antarctica, like the Arctic, is a desert. Unlike the Arctic, Antarctica is a continent. The little snow that does fall accumulates over the millennia, and longer. The Antarctic ice caps have existed for millions of years. Now look at the Arctic. There is very little Arctic sea ice that is over ten years old. (Thanks to global warming, there is very little Arctic sea ice that is over five years old nowadays.)


How do I convert specific humidity to relative humidity?

Relative humidity is just $e/e_s$, the ratio of the vapor pressure to saturation vapor pressure or or $w/w_s$, the ratio of mass mixing ratios of water vapor at actual and saturation values.  If you have specific humidity, which is the mass mixing ratio of water vapor in air, defined as:

$$ q \equiv \dfrac{m_v}{m_v + m_d} = \dfrac{w}{w+1} \approx w.$$

Relative humidity can be expressed as the ratio of water vapor mixing ratio to saturation water vapor mixing ratio, $w/w_s$, where:

$$ w_s \equiv \dfrac{m_{vs}}{m_d} = \dfrac{e_s R_d}{R_v(p-e_s)} \approx 0.622\dfrac{e_s}{p},$$

and from Clausius-Clapeyron:

$$ e_s(T) = e_{s0}\exp\left[\left(\dfrac{L_v(T)}{R_v}\right)\left(\dfrac{1}{T_0} -\dfrac{1}{T} \right)\right] \approx 611\exp\left(\dfrac{17.67(T-T_0)}{T-29.65}\right).$$

Once you have calculated $w$ and $w_s$ you can obtain the relative humidity as:

$$ RH = 100\dfrac{w}{w_s} \approx 0.263pq\left[\exp\left(\dfrac{17.67(T-T_0)}{T-29.65}\right)\right]^{-1}. $$

You could also calculate $RH = 100(e/e_s)$, but I think since you are starting with $q$ it isn't as straightforward as doing it this way.

Variables used:

$q$ specific humidity or the mass mixing ratio of water vapor to total air (dimensionless)
$m_v$ specific mass of water vapor (kg)
$m_{vs}$ specific mass of water vapor at equilibrium (kg)
$m_d$ specific mass of dry air (kg)
$w$ mass mixing ratio of water vapor to dry air (dimensionless)
$w_s$ mass mixing ratio of water vapor to dry air at equilibrium (dimensionless)
$e_s(T)$ saturation vapor pressure (Pa)
$e_{s0}$ saturation vapor pressure at $T_0$ (Pa)
$R_d$ specific gas constant for dry air (J kg$^{-1}$ K$^{-1}$)
$R_v$ specific gas constant for water vapor (J kg$^{-1}$ K$^{-1}$)
$p$ pressure (Pa)
$L_v(T)$ specific enthalpy of vaporization (J kg$^{-1}$)
$T$ temperature (K)
$T_0$ reference temperature (typically 273.16 K) (K)


Here is some supplemental material for the good answer above. It won’t let me comment, http://www.fao.org/docrep/x5871e/x5871e04.htm


Given the weather patterns, it looks like Google Earth is generating those cloud overlays from some recent (i.e., the current day) satellite images.  That line is suspiciously close to the edge of disc line for Meteosat 8, which is located over the equator at 41.5 °E.  I suspect that it's just an artefact of how they're stitching together the various images from geostationary satellites.  The satellite zenith angle and data uncertainty get very large towards the edge of the disc, so most products for forecasting and research are clipped to exclude that region.

Image from EUMETSAT: https://eumetview.eumetsat.int/mapviewer/?product=EO:EUM:DAT:MSG:CLM-IODC


Keep in mind that although I am a paleontologist, I am not a vertebrate paleontologist so I might not be aware of every single find ever made of feathered dinosaur.

As far as I can tell, all dinosaurs fossils exhibiting feathers belong to the Theropoda. Here is a (probably dated) phylogeny of dinosaurs from Sereno 1999:

Credit: Paul C. Sereno

Theropoda is the group from Eoraptor to Euornithes.

While Eoraptor  is Triassic, the group diversifies mostly during the Jurassic (still Sereno 1999) and it is also during that time that we start having "common" feathered dinosaur fossil evidence (e.g. Zhang et al. 2008, Sullivan et al. 2014).
Birds (Aves) seem to have appeared in the late Jurassic / early Cretaceous as well, but modern birds (Neornithes), i. e. birds with living representative, appeared only in the late Cretaceous.

I don't know of any proper (sample-standardized, with coherent bias detection and removal) paleodiversity study for the theropods, although there is one for Aves (Brocklehurst et al. 2012), so it's hard to discuss about it at a species level.

In theory, feathers are more likely to fossilize than other soft tissue (Davis & Briggs 1995) but in practice they are mostly found in finely grained sediments such as limestones, thus limiting the amount of outcrops in which they can be found.

Sources:
Brocklehurst, N., Upchurch, P., Mannion, P. D., O'Connor, J., 2012. The Completeness of the Fossil Record of Mesozoic Birds: Implications for Early Avian Evolution. PLoS ONE 7(6): e39056.
Davis, P. G., Briggs, D. E. G., 1995. Fossilization of feathers. Geology, 23(9): 783-786.
Sereno, P., 1999. The evolution of Dinosaurs. Science, 284: 2137-2147.
Sullivan, C. et al. 2014. The vertebrates of the Jurassic Daohugou Biota of northeastern China. Journal of Vertebrate Paleontology, 34: 243-280.
Zhang, F. et al.  2008. A bizarre Jurassic maniraptoran from China with elongate ribbon-like feathers. Nature, 455: 1105-1108.


If memory serves rifting is defined as either discrete or diffuse. Discrete rifting means that the crust is coming apart in one narrow area, usually in the form of a single defined split in the crust such as at divergent plate boundaries. Diffuse rifting is often seen in backarc spreading and involves many small localised extensional breaks in the crust, each break is small but with multiple breaks spread over a large area the total extension can be quite large. For example discrete rifting can be looked at as a 2 metre break along a single axis while a zone of diffuse rifting would involve several 1 metre breaks each with its own axis, all of which are parallel to each other and perpendicular to the direction of rifting.


How does elevation affect the amount of rainfall received?

Elevation affects temperature which affects the amount of rain. Most raingauges around the world are within a few hundred metres of sea-level, i.e the range in which most people live. Within this range the rainfall-elevation relationship often appears to be linear. However, as the temperature gets cooler with altitude, the maximum precipitable moisture decreases drastically, so the rainfall-altitude curve reflexes back upon itself, so that there is an elevation of maximum precipitation ('EMP'). This variation variies with several factors, such as continentality, 'tropicality', aspect, rain shadow and barrier effect. Some examples of the EMP, are (in metres): Tajikistan 3800,
Alberta Canada 2360, European Alps, 2250, NW Pakistan1500, Oman 1400 to 2200, Kilimanjaro Tanzania 1500, and Hawaii 900. In the case of polar regions the EMP is ground level because the rainfall-altitude relationship is nearly always negative. Above the EMP the rainfall decreases rapidly with altitude, which is why high mountainous regions are essentially deserts.

Wherever there is significant relief in a catchment, the first step is to determine whether the catchment is all below the EMP. The second step is to process the historic record to see if a second order, or even third order rainfall altitude regression is a significant improvement upon 'linear'. If you want further refinement the seasonal rainfalls, or rainfalls from different directions, often have markedly differing rainfall-altitude relationships. If you want to go the whole hog, and be scientific about it, then the rainfall approximates a multi-variate solution, with components of
altitude, altitude squared, aspect, regional trend, rain shadow and barrier effect. This can be solved as an equation of the form: $$R = aH + BH^{2} + cA + dT + eS +f'BE'$$


Confusion on the Nepal earthquake expert statements

I am confused as well. I asked a question at reddit and a kind guy attempted to answer (it was before the 7.3 "aftershock").

This 2012 study investigated the coupling in the area. You can see that coupling is complete at shallow depths throughout the whole zone. You can also see that coupling tends to decrease at depths towards the eastern termination of the rupture zone of the mainshock, and that coupling was increased in the area of maximum rupture during the mainshock (near Kathmandu). Further towards Bhutan coupling increases but variations are smaller than in subduction zones.

This paper investigates ancient earthquake scarps in Bhutan and tells us what a truly big earthquake looks like in the Himalayan region.

If you see the USGS page, aftershock locations are seen to expand outside the rupture area. There are 2 strong aftershocks of particular interest, both around 6.7 magnitude: one at the north-east corner and one at the north-west corner. The fact that they are towards the north is worrying since this is where coupling changes rapidly from nearly 0% to nearly 100%. As Bilham said, during really strong earthquakes even the deeper uncoupled patches slip and add to magnitude. The western aftershock was in an area of minimal slip during the initial earthquake and this surprised me despite the fact that towards the west there were less strong earthquakes in the recent past (so it theory there was room for a strong one), while towards the east there was the 1934 earthquake (which however was not that huge, and additionally in the 80 years since then a couple meters of convergence have taken place, a significant amount of energy).

If you see the 1st link (figure 7) the most suspicious area is a narrow zone near the location of the 7.3 "aftershock" (and near the eastern aftershock as well). However the second most suspicious zone is in western Nepal. So, there are arguments for both sides, the one claiming that towards the west there is room for a large earthquake, and the side claiming that towards the east there is a large possibility for a perhaps less severe earthquake. The eastwards rupture (that compressed waves and perhaps stimulated more fault patches than in the opposite direction) and the uneven distribution of aftershocks favored the eastern side from the very beginning.

The history of Himalayan earthquakes reminds us that 10% of strong earthquakes were preceded by foreshocks or were stronger-than-usual aftershocks (like in this case). However, to my knowledge, the stronger foreshock even recorded was 8.1 (or was it 8.6) in the case of the most powerful earthquake ever recorded. A Mw 7.8 being a foreshock of something stronger would be very unusual, yet from the first day experts were warning for potential giant shocks near Bangladesh. This was in my opinion not correct. Sure the lack of a truly large earthquake in the whole region is unresting, but why now specifically and why there?

Unfortunately I cannot add more links due to being new here. I hope that, even if not helpful, at least I assured you that you are not the only one in confusion.


What ice phenomenon are we seeing in this video?

This phenomenon goes by a number of names: ice heave, ice shove, ice creep, ice tsunami, and I'm sure there are others. It is a consequence of the spring ice breakup coupled with strong sustaining winds on large northern lakes.

The warming spring weather melts the ice close to shore first, making the ice on the lake free-floating. The ice in the middle of the lake can still be close to a meter thick. Winds jostle the ice around, breaking it into chunks. With strong sustaining winds, the ice moves toward the downwind shore. With even stronger sustaining winds, the shoreline is not enough to stop the ice from moving onshore. The ice from further out (and this ice can be very thick) pushes the ice ashore, sometimes bulldozing trees and buildings.

Here's a playlist of 19 youtube videos that portray this phenomenon: https://www.youtube.com/watch?v=0EyfEDKWscg&list=PLPHgakWET6JeATJ1duoGkYItCvfPl26FU . At 32 seconds into the fifth video in the playlist you can see how thick some of the slabs of ice are.


Could the original H. naledi "burial chamber" have originally been at a shallower depth?

2.5 million years is more than enough time for things to change drastically some places, in New Zealand there are mountains whose sediments were seafloor ooze a million years ago, but Africa is not usually one of them. Africa's geology is normally far too stable to show major changes on that short a timescale. In the normal course of things a given position in a cave system becomes shallower as time goes on due to surface erosion. What I can find on the Monte Christo Formation that holds the Rising Star Cave and the surface survey here suggests that there have been no major deposition events since the caves were formed, this would suggest that in fact the fossils were even deeper under ground when they were deposited.

It is however possible that there was a transient hole in the roof of the cave that has since filled with redeposited minerals and is no longer evident, such are not unheard of in karst terrain and would have supplied light to great depths. The bones may also have originated closer to the cave entrance and been swept deeper into the system by flooding at a later date.


How far would average sea level rise from a 25% increase in total ocean volume?

It is not hard to do this calculation if you have global topography. Using a version with $\frac{1}{6}$- degree resolution and a sea level rise of 1027 m, the result is @Erik's value of 445 million cubic km. Here's the bit of MATLAB code:
H = 1027;   % sea level rise (m)
topo(topo<0) = 0;   % change all ocean depths to zero
topo(topo>H) = H;   % level off all land at a height of H
topo = topo.*(cosd(lat')*ones(1,2160)); % land volume per grid cell
land = sum(topo(:))*18.5^2/1000; % total land volume in km^3
water = sum(cosd(lat))*2160*18.5^2*H/1000 - land; % added water volume

Greenland and Antarctica fare ok, but Europe and Australia are basically gone:


Other than tectonic activity, what can reshape a world's surface?

Erosion is a powerful but slow and time consuming process that can make dramatic changes. The best example of this is the Grand Canyon. Carved by a river over at least 17 million years, 5000 to 10,000 feet deep, 277 miles long and 18 miles wide.
Erosion, whether it be due to wind, rain, water flow in rivers, glaciers is a major cause of geology, in the form of mineral grains, boulders and rocks to be mobilized and dispersed over a wide region.
Weathering is another force that reshapes the surface of the Earth. Australia is a perfect example of this. Weathering results in the physical breakdown of the of the surface geology due to weather, thermal stresses, frost, crystal formations and decomposition, oxidation, biological activity, alternating patterns of hydration and dehydration over a very prolonged period of time. The difference between erosion and weathering is erosion causes movement of material, weathering happens  in situ.
Fire tolerant plants such as eucalyptus and fire as a result of natural forms of ignition, such as  lightening  can change the botany of a large region, again see Australia. Eucalyptus has been described as a weedy tree that came to dominate a landscape when less fire tolerant plants became extinct.
Persistent fire or drought over a prolonged period can lead to permanent loss of flora resulting in desertification. Similarly, excessive rain due to climate change can lead to landslides and excessive erosion.


Would an oceanic asteroid impact really cause a tsunami?

An asteroid impact in the ocean is an oversized example of throwing a pebble in a pond - both will produce waves in a concentric pattern from the point of impact.

The height of the waves and the energy they would have would depend on the amount of energy the asteroid transferred to the water at the impact sight.

The energy transferred will depend on the kinetic energy of the asteroid at the moment of impact, this being a function of the mass and velocity of the asteroid; based on the classical equation for kinetic energy: $E_k = 0.5mv^2$.

Hence, an asteroid with a very large mass and high velocity could transfer enough energy that could create tsunamis. The best example of this is the impact that created the Chicxulub crater in the Yucatan peninsular, that lead to the creation of the K-T boundary and the extinction of the dinosaurs.

That impact created a mega tsunami that affected the coastal southern state of the USA, from Texas to Florida.


How many extreme shifts in climate has Earth gone through in its existence?

As I finished writing this question I did find one answer. I'll ask anyway and see if anyone has more info to contribute.

From the Wikipedia page on Ice Ages, there's this Timeline of life including a list of ice ages on left side.

Based on this, there were 7 ice ages in the past 4.5 billion years (apx age of the Earth). Were there also 7 major periods of high volcanic activity?


Feldspar content of coarse-grained igneous rocks

You can't really generalize like that for all igneous rock ranges.  The chart actually tells you what the type and (approximate) mineral composition of a rock are as functions of the chemical composition, specifically silica content.  You should be looking at how the minerals are distributed as a function of silica content.
To understand this diagram fully, note the following:

The horizontal axis is actually a continuous variable, typically the silica content you would obtain if you were to separate all the individual oxide components.  This diagram seems to go roughly from 50% to 70% from left to right; the one quoted here which includes rocks found predominantly in the mantle goes down to 40%.

The rocks are classified according to silica content and crystal or grain size; thus granite and rhyolite are similar in silica content and are regarded in the diagram as having similar mineral compositions; only the grain size is really different.

Thus the curved lines define how much of each mineral is typically in a rock having some level of silica content, which varies across the chart as indicated in point (1).  When we have a high silica content more than about 65% (felsic rocks) in a granite or rhyolite, there can be more alkali feldspar than plagioclase feldspar (the alkali feldspar composition range is higher in silica).  In contrast, a low-silica (mafic) rock won't have any alkali feldspar and even the more flexible plagioclase feldspar is limited; mafic rocks are higher in other minerals such as pyroxenes.


Why do Earth and Venus have different atmospheres?

Note: This response is bereft of references. I'll try to add them later.

There is no definitive answer. There are a lot of conjectures, however.

Whatever the cause, the Earth is markedly void of carbon compared to Venus. The amount of CO2 in Venus atmosphere corresponds to a 0.88 km thick layer of carbonate. The Earth's geosphere (lithosphere plus oceans plus atmosphere) collectively contains about half that amount of carbon, almost all of it locked up in the lithosphere. The huge amount of carbon in Venus atmosphere versus the paucity of carbon in the Earth's atmosphere is the primary factor that distinguishes the two atmospheres.

Planet formation. The leading hypothesis regarding the late formation of the Earth is the giant impact hypothesis. Multiple simulations suggest that this collision had to be rather oblique. An oblique collision between a Mars-sized body and a not-quite Earth-sized body would have drastically changed the Earth's rotation rate prior to and after that collision. If the Earth was rotating very fast prior to the collision, that fast rotation combined with the collision could have resulted in the Earth losing a large chunk of its primordial atmosphere.

Venus does not have a large Moon. That suggests that it's formation was a bit less tumultuous than the formation of the Earth. With no big collision to eject that primordial atmosphere, Venus may well have been operating in runaway greenhouse mode from the very onset.

Water. Whether Venus first had free water on its surface or in its atmosphere has long been a subject of debate. Venus is now nearly devoid of water. If water was present in Venus early atmosphere, it would have served to even more strongly magnify the already huge greenhouse effect of a thick atmosphere that is opaque in the thermal infrared frequencies. If the very young Venus did have liquid water on its surface, it wouldn't have lasted very long.

Plate tectonics. One of the consequences of a very thick atmosphere and no liquid water is no plate tectonics. Venus has a very thick greenhouse atmosphere, which makes for a very hot surface. The high temperature of Venus's surface means the surface healed itself too rapidly. Plates couldn't form on Venus (Bercovici 2014). Water is an important lubricant for plate tectonics, particularly for subduction (Mian 1990). (But also see (Fei 2013) for an opposing view.)

With no plate tectonics, there was no mechanism to bury carbon inside of Venus. Plate tectonics developed fairly early on in Earth's history. By the time the Sun became hot enough (the early Sun was faint), the Earth had already started the process of sequestering away carbon into the lithosphere.

Life. Life loves carbon. It is one of the key agents by which atmospheric carbon is transferred to the lithosphere. Life apparently never had a chance on Venus.

References

Bercovici D. and Ricard Y., "Plate tectonics, damage and inheritance," Nature 508, 513-516 (2014)

Fei et al., "Small effect of water on upper-mantle rheology based on silicon self-diffusion coefficients," Nature 498, 213–215 (2013)

Mian Z. and Tozer D., "No water, no plate tectonics: convective heat transfer and the planetary surfaces of Venus and Earth," Terra Nova 2:5, 455-459 (1990)


What is the better way to deal the missing and negative cells of satellite snow cover data

You could fill the gaps with the analysis products of numerical weather prediction. NCAR for example (RDA UCAR) hosts the NCEP North American Regional Reanalysis (NARR) with data from 1979 to 2018 including snow cover (NARR) in 3-hourly intervals.

But I would guess it depends on your goal:
You can make an educated guess (bayesian approach, combining measured and predicted variables) about the true state of the snow cover, but what was not measured can not be pulled out of nowhere.


How did forests end up covering pyramids?

I am an archaeologist and I specialize in the ancient Maya. Here's how it happens:

1: The vast majority of ancient Maya buildings are built using a "core and veneer" technique. The bulk of the building's volume is earth and stone rubble, faced with a veneer of nicely-shaped limestone blocks that are themselves covered by a layer of lime plaster (stucco). The geology of the Yucatan peninsula is almost entirely limestone, so they built with what they had available.

2: Most pyramids have multiple construction phases, with each one adding a new layer of rubble/earthen core and cut stone and stucco veneer. The building gets bigger with each renovation.

3: Following abandonment, strong seasonal rains quickly erode the lime stucco on much of the outermost layer. This eroded stucco is chemically and structurally identical to the eroded bedrock that underlies natural soils in the Maya region, meaning that plants can readily grow on it.

4: The limestone used for cut stone veneers is itself really porous and prone to crack, pit, and erode in most parts of the Maya lowlands. I am constantly seeing small trees growing out of ostensibly solid blocks of limestone--their roots can still get plenty of purchase. As such, trees can easily take hold in the space between blocks and in small imperfections in the stones themselves.

5: As the trees grow (and especially as their roots push or pry out loosened veneer stones), the cut stones from the veneer give way, exposing the earthen/rubble core underneath.

6: Other posters are correct that some topsoil builds up as a result of wind-transported dust and decaying plant matter, but this is a very, very small amount, especially on the steeper upper portion of the building (remember, the buildings become less steep overall as they erode, because what had been on the upper part tumbles down and piles up around the base, reducing the gradient). Instead, most of the "soil" was actually put there by the Maya as part of the final construction phase, covered by a layer of modern humus.

7: It follows that in many parts of the Maya world, what you see when you look at a cleared/restored pyramid is not really what it looked like in its final stage. Instead, it's usually a mix of the last and second-to-last construction phases, both having been subject to varying degrees of erosion, with the last phase usually only preserved toward the bottom and at the very top.


Could saltwater be useful for greening deserts and sequestering CO2?

May the right aproach is, improve the process to turn saltwater into fresh water cause the only thing that i know which can be food and has salt tolerance is palm tree, mangrooves demmand a highly amount of seawater meeting a river


How can I define frost based on a weather record?

The dew point is the temperature at which water condenses from the atmosphere. When the dew point temperature is below the freezing point of water ($0$ $^oC$, $32$ $^oF$) frost forms.

Most weather data includes dew point temperatures. Search your data for when the dew point is below the freezing point of water.

If your data does not you will need to calculate it to find when it is below the freezing point of water. The formulas here will help.


Is there any case that changed from earthquake safe zone to danger zone?

Yes, prior to 1983, central Idaho was classified low to moderate.  On October 28, 1983,  a  powerful earthquake occurred in Lost River Range at Borah Peak in central Idaho. The shock measured 6.9 on the moment magnitude scale and had a maximum Mercalli intensity of IX (Violent).

The earthquake was centered only 50 miles from a Idaho National Engineering Lab (nuclear research laboratory), but no damage was reported a the site.

Unfortunately, I can't find an internet accessible report but I remember discussing this earthquake at length in a Engineering Geology class I was taking in 1986.  The magnitude of the Borah Peak surprised the US government prompted the USGS to reclassify earthquake hazard zones in Idaho and Utah.

Location of Borah Peak, Idaho.

Current quake hazard map (from USGS:)

References:

Wikipedia Borah Peak.
New York Times article on quake
Geological summary of the quake: Idaho State University By, Steven W. Moore, Geologist and R. David Hovland, Geologist:


Would the shaking of an earthquake be visible to somebody in a low-flying aircraft?

It depends largely on how deep, or shallow, the earthquake is, how large, and what kind of terrain you're looking down on. Some fairly large earthquakes, magnitude 6-7, can have very little surface effect, when they are centred 5+km down as many earthquakes in New Zealand often are. The finer the sediment on the surface, and the thicker the sediment cover, the greater the ground shaking is at the surface and the more motion is usually visible. Different ground covers will also make shaking more or less visible, long grass, or cereal crops, on a windy day will look like they're in motion even without a 'quake.

Shallow earthquakes often result in apparent L-wave activity, by which I mean that you can actually watch the ground wave coming towards you if you're outside on relatively flat ground, even during relatively small 3-4 pointer 'quakes. These waves also make parked vehicles rock from side to side, I would expect these effects to be the most visible from the air in the case of small to moderate earthquakes.

Larger 'quakes will cause noticeable shaking of buildings, power poles, aerials etc... even when quite deep and possibly distortion to large linear features such as roads, railways, waterways, and crop and orchard rows. These distortions would be visible as they form, and, when large enough, from very high in the air.


(How long) would Earth's atmosphere last without a global magnetic field?

Atmospheric escape is a topic with a long research history. It is complex and is being addressed with both measurements and simulations.

For example, the question of atmospheric escape is still actively researched at Mars, and the MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft mission is for example dedicated to this topic. Mars is a planet without a significant global magnetic field (although it does possess crustal magnetic anomalies); in fact its planetary dynamo was active and then stopped about 3.6 billion years ago, which considerably reduced the strength of its magnetic field.
So understanding the evolution of its atmosphere helps to relate to what would happen if Earth would loose its magnetic field. The question of atmospheric escape at Mars is relevant concerning the fate of water (geological evidences indicate the presence of liquid water in the past, which suggests a warm and dense atmosphere able to support it at that time).

Besides thermal atmospheric escape, there is also non thermal escape, including removal by asteroid impact (in the past) and by interaction between the atmosphere and the solar wind leading to pickup of atmospheric ions (in the past and continuing today).

Some examples of references to the scientific literature about atmospheric escape at terrestrial planets (abstracts):
Outgassing History and Escape of the Martian Atmosphere and Water Inventory
or
Nonthermal escape of the atmospheres of Venus, Earth, and Mars


How come the tide is low when the moon is high in the sky

This is based on the overly-simplified model of tides being the result of tidal bulges. As I explained in my answer to a related question on the physics.SE sister site, those tidal bulges do not and cannot exist.

Instead, the tides are dynamic responses to the tidal forcing functions from the Moon and the Sun, with the orbits of the three bodies about one another, the Earth's rotation rate, and the geometry of the oceanic basins all playing roles in the dynamic response. For any point on the surface of the Earth's oceans, the tides can be described in terms of a composition of frequency responses to those cyclic forcing functions. See the related question Definitions of tidal harmonic constituents…? for details.

At many places, Fiji included, the key component of the tides is the $M2$ tidal constituent, with a period of 12.42 hours. This is the principal response to the tides induced by the Moon. If Newton's equilibrium (tidal bulge) theory of tides was correct, every oceanic place on the Earth's surface would see high tide when the Moon is at zenith and nadir, and low tides when the Moon is at the horizon. Except for a few places, this is not what is observed. In Fiji, the situation is nearly reversed, as depicted by the tide chart below for Nadi on the west coast of Viti Levu, where high tides are more or less in sync with moonrise and moonset.

Source: https://www.tide-forecast.com/locations/Nandi-Waters-Viti-Levu-Fiji-Islands/tides/latest, accessed 2 November, 2017.

Laplace's dynamic theory of the tides says that the oceans' response to each of the tidal constituents comprises a set of amphidromic systems. Each such system is centered about an amphidromic point, a place with a null response to the component in question. A wave whose amplitude increases with distance from the the amphidromic point rotates about the amphidromic point at the constituent frequency. The $M2$ tidal response is depicted below. The $M2$ amphidromic points are at the centers of the dark blue areas. The white lines emanating from the amphidromic points are cotidal lines, curves along which high tide occurs at the same time. The different colors indicate height, which again increase with distance from the governing amphidromic point.

Source: http://en.wikipedia.org/wiki/File:M2_tidal_constituent.jpg.


Where does water vapor go/what does the sun do?

Simplistically, fog consists of water droplets.  The sun provides energy, which heats the droplets and evaporates them, and also raises the air temperature.  The water is still there, it's just in the form of (transparent) water vapor, rather than light-scattering droplets.

PS: Maybe a similar example would help make things clear.  Say you've just washed some clothes, and hang them on the line, and some time later they're dry.  There was water in the clothes when you hung them out, it didn't drip off the bottom, so where did the water go?  Into the air, as vapor, no?  Same with fog, when the sun raises the temperature a bit.


I answered this question on SustainableLiving.SE. Since no one voted to close this as off-topic, I'll link and summarize my answer here.

I'm glad you asked for it by calorie, since answers on that question had found the data by kilogram, which is not a particularly useful measure. The data source for carbon per kilogram is the Meat Eater's Guide from the Climate Working Group (I believe this is the same as the website you linked, as well); I did the kilogram to calorie calculations from nutritiondata.self.com which gets its numbers from the FDA.

You can read my entire answer, but I will copy the data table for your convenience. Units are kg carbon dioxide emitted per 1000 calories.

Lamb         20.85
Beef         13.78
Turkey        5.83
Broccoli      5.71
Tuna          5.26
Salmon        5.15
Cheese        4.47
Pork          4.45
Yogurt        3.49
Chicken       3.37
Milk          3.17
Eggs          3.06
Rice          2.08
Potatoes      1.46
Beans         1.40
Tomato        1.39
Tofu          1.38
Lentils       0.78
Peanut Butter 0.42
Nuts          0.39


That is not a silly question! And your intuition is correct: As you bury and compact a sedimentary rock, its porosity will decrease, so its density increases. But we also see that its velocity tends to increase. This appears contrary to what that equation shows.

However, as you bury the rock and decrease its porosity, you are simultaneously increasing the rock's effective stiffness (bulk and shear moduli). And yes, this effect overwhelms the density effect so the outcome is a faster P-wave velocity. So even though the derivation of this equation from continuum mechanics tells us that stiffness and density are independent parameters, they seldom are in nature. Most geological scenarios where density would increase, also raise the effective stiffness of the rock.

But here is an example where this is not the case. Imagine you have sandstone between two shales. The sandstone has some porosity and it is completely filled with brine. If that exact same sandstone (i.e. holding everything else constant) is now filled with gas instead of brine, its Bulk modulus will go down by a lot and Density will also go down but by less. However, according to Gassmann's equations, the Shear modulus will stay constant. So the P-wave velocity goes down because the Bulk modulus effect overwhelms the Density effect and the Shear modulus doesn't change. But now consider the S-wave velocity whose equation is $v_s = \sqrt{μ/ρ}$. In this case there is no Bulk modulus to overwhelm the density and so the S-wave velocity will actually go up by a small amount when the rock is saturated with gas. This is purely a density effect.

This effect is commonly observed in hydrocarbon exploration where they have drilled a well into a sandstone that is full of water, but then go up dip and find something like an anticline where the same sandstone is now full of gas.


What kind of rock is this being eaten by a rock-eating worm?

thank you for your interest in the article. I'm the lead author on this paper (Shipway) and I happened to come across your post when looking through all the media stories on this animal.

To answer your question; yes, you're right, the rock is a calcareous sandstone. It was easy to split, partly because it is a naturally soft rock and partly because the shipworms had weakened the structure.

Hope that answered your question.


To what year do we need to return to prevent climate change?

As Gemechu Fanta Garuma commented, the IPCC Assessment Reports (at time of writing, AR5 is the latest) and its special reports are the best place to go for a comprehensive summary of the science as it was a small number of years ago.

In terms of greenhouse-gas concentrations that are stable and civilisation-friendly, the range 300-350ppm CO2 is as useful a range as we're likely to get for now - 350 is when coral bleaching starts to become a serious problem, and trashing the ocean ecosystem is a shortcut to threatening human civilisation, so we should probably avoid that. And for methane, say around 1000-1300ppb.

It's not a question of "returning to a year". We don't need a time machine, and we don't need to wind back everything that's happened. I've no wish to return to 1980, for example, and I'm not sure why anyone else would (I was there and it was largely rubbish). This is not about undoing decades of human progress. What we do need to do is to keep the concentration of greenhouse gases in the atmosphere at levels that keep the climate fairly stable at the timescales of human lifetimes, so that we avoid massive disruptions and a potential threat to human civilisation. Had we started doing that when this was first flagged up as a major issue by scientists in the 1970s, we would have done it much cheaper, much sooner, and with less collateral damage. (like in the old proverbs: an ounce of prevention is worth a pound of cure; and a stitch in time saves nine)

We have already caused some climate change. It will take 30 years for the full effects of what we've done to date, to show up. We may already have caused trillions of pounds of damage to our natural capital - but we'll only know the full scale of the damage when it's far too late. Theoretically, we could avoid some of that damage in the next 30 years by putting the global economy to work to tackle the problem seriously. However, the political will just isn't there. Most of the people who'll suffer the worst of the damage are too young to vote, or haven't been born yet. Most of the people with the ability to do something about it (voters, politicians, business leaders) will be dead before the worst of the damage hits.

The Keeling Curve shows how atmospheric CO2 concentrations have changed over time:

(chart Scrippsnews - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=69539214)

As for the relationship between atmospheric concentrations of greenhouse gases, the change in average global temperatures, and actual changes in climate, that's a set of very complex relationships wrapped in uncertainties and unknowns. And these things are generally nowhere near as simple as a neat, reversible one-to-one function: even if we were to restore greenhouse gas concentrations to where they were in 1980, does not mean that the climate will return to just as it was then.  And that's why mitigation action is so very urgent: we are driving in thick fog very close to the edge of a cliff. The smart thing to do is to stop driving and work out what's going on. Which means getting to zero net emissions as fast as we can without destroying everything else in the process.


Does evaporated hand sanitizer pollute the environment?

Assuming you are talking about ethanol: it is a common chemical substance, generated naturally from e.g. rotting fruits. So any pollution from hand sanitizers should be negligible.
What happens to the alcohol in the atmosphere is an interesting sequence of reactions. I took the info below from an article (see link below).
In the air, ethanol is oxidized quickly (half-life is a few days) into acetaldehyde $CH_3CHO$, which is further oxidized into other compounds, most of which are harmless. However, if the air contains nitrogen dioxide $NO_2$, it can form peroxyacetyl nitrate $CH_3C(O)OONO_2$, which is dangerous.
Source


Above average global temperature in March 2016

What happens in one city in one month is only a very very small part of the picture. You can make very little inference on global warming based on the weather in one city in one month.

You can make a little more inference on global warming based on the weather around the world in one month.

And we can say a lot about global warming based on the world's weather over a 30-year period.

A lot of heat got released from the ocean last year in the El Niño event: heat that had been accumulating in the oceans for a few years. That heat is now getting distributed around the world, which is why we're seeing rises in global surface temperatures - a similar thing happened back in 1997/8. The Earth has been accumulating a lot of heat for years, and it's now showing up as rises in surface temperatures.

The accumulation of heat is happening because the Earth has been absorbing more energy than it has been radiating away into space. That has happened because of human emissions of greenhouse gases, in particular, but not exclusively, carbon dioxide and methane.

Unnatural global warming started decades ago. Now, it's accelerating.


I actually witnessed this in Ashland, OR several years ago. A strong winter storm had just passed when there was a sudden, brief downpour. When I looked up, there was not a cloud in the sky. What I believe happened is that the air was supersaturated with moisture when a brief breeze caused water to condensate around the few nuclei available. This seems to be confirmed by the second scenario in this explanation: Consider the very rare situation in which still air is supersaturated with moisture (its relative humidity is above 100 percent) and clouds have not formed because condensation nuclei are practically nonexistent. Water vapor will quickly condense onto the few nuclei that are present and the droplets will rapidly grow into raindrops.This is the one and only time I have ever experienced this.


What is the age of the earliest traces of life on Earth?

Fossils are our strongest, and to most people most accessible, evidence of the great age of life on earth. The fossils in the Burgess Shale are clearly the imprints of critters, but are a mere 505 million years old. The oldest cyanobacteria-like fossils known are nearly 3.5 billion years old, among the oldest fossils currently known. There is Evidence for biogenic graphite in early Archaean Isua metasedimentary rocks, but requires knowledge of isotopic chemistry to understand (or dispute.) Life on earth originated before 3.5 billion years ago.


Can large (and wet) storms really trigger large magnitude Earthquakes?

The 2011 AGU poster has been cited once, by Burtin et al. (2013)1, who say in their abstract ... event activity was positively correlated with the precipitation intensity... -- but more importantly, in the body of the paper, this:

  Furthermore, it has been argued that rainfall may affect the occurrence of earthquakes, either by downward fluid diffusion from the surface [e.g., Bollinger et al., 2007] or by erosional unloading of active faults [e.g., Wdowinski and Tsukanov, 2011], but these mechanisms require exceptional or very prolonged precipitation and they are likely to entail significant delays between the meteorological driver and seismic response of up to years. For
  these reasons, we also rule out rainfall-triggered seismicity as a possible source of the near-surface activity we have detected.

Note, however, that over the course of the study they recorded 29 events, of Ml 0.7–5.7.

Meanwhile Sobolev et al. (2012)2 - in a journal I do trust - say in their abstract:

  This study is concerned with the effects of powerful Pacific cyclones on the seismicity of Kamchatka, Japan, and the Philippines. We used complete seismological catalogs for these regions that span a few tens of years. It was found that the cyclones that originate from the western Pacific generally do not exert a significant triggering effect on the seismicity of these three regions, at least in the short term, during a few weeks. The ground motion generated by cyclones, which might be treated as a trigger, does not have amplitudes above those in the motion due to numerous local earthquakes of moderate magnitudes (∼4–5) and larger teleseismic earthquakes.

The only two recent publications claiming any link at all between cyclones/extreme precipitation events and significant seismic activity (i.e. not "minor" landslips) are from sources I don't trust: a 2013 paper in a journal I've never heard of (International Journal of Geosciences) before, and a 2014 publication in "Natural Hazards and Earth System Sciences Discussion. I'm dubious about them not because they are open access but because I am concerned about methodology and sources.

While this mechanism was mentioned to me as plausible as an undergraduate at Cambridge in approximately 2012, the department's view seems to have shifted (per Burtin et al - Neils Hovius is very senior in the dept). The current evidence does not appear to support any short-term link between extreme weather events and significant seismic activity. Long-term links have not been ruled out but I have not found any substantiating evidence for such connections.

1 disclaimer: it turns out I know two of the coauthors, including one of the senior ones, personally.

2 Original in Russian also available


Oil can be generated from pretty much anything organic. The oldest oil that I know of comes from a porous Eocambrian siltstone in the Sultanate of Oman. This was formed nearly 200 million years before there were any fish around.
Apart from that, oil can be formed in any of the geological eras up to the late Cenozoic.


How to interpret the values of moisture flux convergence?

MFC can be employed to detect frontal structures and possible storms, which can be related with high values of MFC, which means convection of winds with high quantity of moisture...

In a field map, you will be able to identify fronts as structures with high values of MFC. Try to plot along with pressure field for better understanding if you are able to.

Find more info here:
http://www.spc.noaa.gov/publications/banacos/mfc-sls.pdf


What is the total weight of mineral extractions from Earth per year?

This may give you some useful information. You can download the World Mineral Production (2011-2015) produced by the British Geological Survey at this link. This publication has data for approximately 70 different commodities by country and world totals (tonnes).


What tectonic structures exist on the Eurasian - North American plate boundary in eastern Siberia?

This plate boundary is one of the least understood in the world, primarily due to the remoteness of the location meaning that there has not been long term observations of seismicity etc.  However, it is not a forgotten boundary and has come under recent scrutiny.

One of the most comprehensive studies of the area was Stanford University's Plate Tectonic Evolution of Northeast Russia, 2004 that produced the following tectonic map:

The workshop participants describe the plate boundary as transitioning from the ultraslow spreading of the Gakkel Ridge in the Arctic Ocean, across the diffuse extensional zone in the Laptev Sea in the north, into the diffuse transpressional 'Moma Rift'.

They describe the uniqueness of the plate boundary as the Euler pole of rotation occurring on or near the plate boundary itself (labelled as NA-EU Pole in the diagram above), which results in the general extensional in the north and compressional complexes in the south.

Further research presented in the conference paper Recent geodynamics and evolution of the Moma rift, Northeast Asia (Imaev et al. 2009), suggest that the "Moma Rift" was once an extension of the Gakkel Ridge and was a extensional rift, but as the Pole of rotation moved, it has become transpressional - with an uplift of up to about 4mm/year, representing a convergent section of the boundary.


Why would CaO be more finely spread than K2O in Granodiorite?

I would suggest that there is a combination of effects here:

Potassium(K) compounds are usually more soluble than their Calcium(Ca) equivalents, and often at much lower temperatures. For example $CaCO_3$ is in considered insoluble in even boiling water, while $K_2CO_3$ is fully soluble at room temperature. Potassium can therefore migrate more easily during weathering involving water infiltration than can Calcium leading to a finer distribution. The "clumps" of $CaO$ represent more closely it's original crystal positions while the finely divided $K_2O$ has migrated farther dispersing it through the samples.

The clumping in less weathered samples could be purely an artifact of the nature of the parent rock Granodiorite is relatively enriched in Calcium over Potassium so Calcium shows up as large concentrations while Potassium is more thinly spread through the samples.


Rock identification ? What kind of it is?

Looks like slate to me.
The geological map of Trinidad suggests that the local rocks are shale, which is similar to slate but less compact.


What does the containment percentage mean when a fire department is reporting on a wildfire?

One hundred percent contained means that there are suitable fire guards around 100 percent of the circumference of the fire.  The fire guards can be either created such as a hand or machine dug firebreak, a retardant break (often placed by air tanker), or a natural feature such as a river or bare rock cliff.  Containing a fire is just a step in controlling the fire, after containment, there are other phases that may or may not be completed such as back burning off the break lines, extinguishment, and finally monitoring.  Even once a fire is 100% contained it is not that uncommon for the fire to "jump the guard" if the weather conditions change.  The percentage of containment also gives an indication as to how much access the fire crews have to the fire, a well-contained fire implies that the fire crew has access to be able to fight the fire, this is the major secondary goal for the dug firebreaks.

5 percent contained implies that some form of command has been established and the fire crew(s) are just starting to contain the fire.  I wouldn't read much more into the statement.


If I build a concrete surface on a 1km x 1km area and painted it black, will I create convection (updraft from ground)?

In principle: yes. But i won't give exact numbers for a mere km², though i'd expect a skilled paraglider under optimal atmopsheric conditions to be able to make some use of it ;-)

Actually, gliders use industrialized areas exactly because of this, a low albedo created by asphalt, concrete, dense construction/building.

How high and strong the resulting thermal convection will be depends on the weather, atmospheric layering, solar irradiation, wind, cloud cover, temperature and moisture. The ability of the ground to store heat (e.g. street canyons, or heat strored in the air of a high grown cornfield) also influences the triggering of convection. In some cases a rising thermal is visualized by a dust devil.

Thermal convection can be calculated/estimated and predicted from atmospheric soundings, instrumented weather balloons to measure the state of the atmopshere from ground to tropopause. The results are visualized in Skew-T or Stüve diagrams.

Reading and interpreting them is an art. But they can tell when the trigger temperature for thermals will be reached, how high they go, if there will be clouds and at which level their base is, etc.

Side effects of this are called urban heat islands or generally heat islands due to low albedo ground. They can cause local low pressure due to the rising air over the hotter ground, which can result in showers or even thunderstorms in the evening/afternoon.

Quite obviously, these effects can also be triggered by naturally occurring differences in ground albedo and plant cover. They are a driving force for local weather phenomena.


What caused those colorations in bedrock?

This answer is based on a cursory look at the 1:50000 Foglio Appiano, from the Geologic Map of Italy (in Italian Language only, as far as I can tell). As I pointed out in comment, I intend it as just a start for further investigations, which should be done with more detailed geological works and possibly more field work. I'd recommend contacting the office of the Geological survey of the Provincia di Bolzano as they certainly know the area well and may be able to answer on the phone or by email.

This is what I think, based on my cursory look.

The cross section C goes ~E-W just north of the town of Cornaiano, relatively close to the location of the Church, which is just West of San Michele (based on Google map link); I indicated its approximate whereabouts with yellow circle in the figure below. It looks like the rocks in your picture could be an outcrop of the ORA formation (in orange in the figure), a Rhyolitic tuff of the Atesino volcanic group.

Also the Schema tettonico below (look for Appiano) shows the Atesino volcanic group and is in contact with a very faulted sedimentary section (Successione sedimentaria permocenozoica); I'd say geothermal fluid circulation through these fractures causing hydrothermal alteration at surface is a plausible explanation for the coloration you captured.