|Through a simple online model, students learn about the relationship between average global temperature and carbon dioxide emissions while predicting temperature change over the 21st Century.
| Climate model interactive developed by Randy Russell.
Guide for educators developed by Lisa Gardiner.
Student Learning Outcomes:
|Computer interactive plus optional assessment
- Ask students what they have heard about future climate change from newspapers, the Internet, and television. If time allows, have students find and then share articles about future climate change. Discuss how greenhouse gases, such as carbon dioxide, that are emitted to the atmosphere are, in large part, causing recent climate change. The Windows to the Universe page entitled Global Warming: Scientists Say Earth Is Heating Up provides a summary.
- Tell students that models are used to predict how Earth's climate will change in the future. In general, a computer model uses math to describe how the Earth works. Have students read the Windows to the Universe page entitled What Is a Climate Model? and then discuss what models are. (You may wish to have your students continue on and read How Climate Models Work and Accuracy and Uncertainty in Climate Models too.)
Interactive Activity: Part 1 - Learning how the model works
- Tell students that they will use a model to test what will happen to the atmosphere and climate over this century depending on the amount of carbon dioxide released into the atmosphere.
- Familiarize students with the axes of the graph where data from each model run will plot (see figure below.) The x-axis shows years into the future. The y-axis has three different scales: (1) carbon dioxide emissions rate, (2) carbon dioxide concentration, and (3) average global temperature.
- Introduce the variables to the left of the graph (see figure below) that students can manipulate as they run the model. The carbon dioxide emissions rate is measured in gigatons of carbon dioxide per year. Depending on your students' math skill level, you may wish to introduce the concept of rate at this point.
- Ask students what would happen to Earth's temperature in the future if each year we released the same amount of carbon dioxide into the atmosphere as we did in the year 2000. That rate was around 6 gigatons of carbon per year (6 GtC/yr). Instruct students to set the carbon dioxide emissions rate to 6 gigatons (it should be set to 6 as the default.) Instruct students to set the "Timestep size" to 10 years using the popup menu. This means that every time they tell the model to advance, it will move ahead 10 years of "model time."
- Instruct students to click the "step forward" button 10 times to get data to appear through the 21st Century. Each time they click the button three points will appear on the graph. The color of these points correlates with the colors of the three y-axis measures. (The figure above shows the resulting graph.)
- Discuss as a class what this graph is showing.
- The blue dots (emissions rate) represent how much carbon we add to the atmosphere each year. Since the rate stayed the same for this model run, the blue dots form a horizontal line on the graph.
- Black dots represent how much carbon has accumulated in the atmosphere over time. Units are "parts per million by volume" (ppmv). For reference, the actual concentration was around 368 ppmv in the year 2000. In this run, the concentration rises from around 400 ppmv to over 600 ppmv by the year 2100.
- Red dots represent average global temperature in degrees Celsius. For reference, this value was around 14.3° C in the year 2000. In this model run, the temperature steadily rose to about 17.5° C by the year 2100. In this simple model, the temperature is determined entirely by the atmospheric CO2 concentration via greenhouse warming of the atmosphere.
Interactive Activity: Part 2 - Testing different scenarios of climate change
- Ask students if they think the first model run will reflect what people will do over the 21st Century. The actions of humans are the largest unknown when it comes to future climate change. Survey student opinions: Will we release the same amount of carbon dioxide into the atmosphere that we do now? Will we release less? Will we release more?
- Brainstorm how and why carbon emissions may change in the future. For example, carbon emissions will go up if more power plants are created that burn fossil fuels, yet carbon emissions will go down if more technologies are invented that reduce the use of fossil fuels.
- Based on the survey and brainstorms, have students work in groups to come up with a scenario that they would like to test. (Example: carbon dioxide emissions rise through the middle of the 21st Century, and then decline after that.) To be somewhat realistic, they would need to start with emissions at 6 GtC/yr since that is what it was in the year 2000. To help students focus as they run the model, have student groups write out their scenario in a paragraph before they begin.
- To reset the model so that it can be run again, instruct students to click the "Reload" or "Refresh" button on their web browsers. Instruct students to set the timestep as 10 years as they did before. Demonstrate for them how they can change the emissions rate during the Century by changing the rate, clicking "step forward", and then changing the rate again. (For example, if you had decided to increase emissions for the first half of the century and then decrease them for the last half, you would need to increase the rate for each timestep for the first 50 years and then decrease the rate for each timestep for the last 50 years.)
- Discuss as a class the results of various student scenarios: What happened to temperature and carbon dioxide concentrations over time? Is some global warming enevitable? Which scenario had the least warming? Which had the most?
You may wish to have students (or student groups) present their results from Part 2 to the rest of the class in an oral report, posters, or powerpoint slides.
Have students make an experiment using the Very, Very Simple Climate Model by testing whether there is a difference in resulting global temperature between two scenarios.
Have students read the page Tackling the Global Warming Challenge and then brainstorm things they could do to reduce the amount of greenhouse gases that are released into the atmosphere.
Combine this activity with Carbon Dioxide: Sources and Sinks and the Carbon Cycle Game to develop student understanding of where atmospheric carbon dioxide comes from, where is goes, and how long it stays in the atmosphere.
Climate scientists use models to understand how the Earth is changing. Models of Earth can be experimented upon to assess the impact of various perturbations on the planet. Climate models describe our planet with mathematical equations. Because Earth is complex, it takes hundreds of very complex equations to model the atmosphere, oceans, and land surface. Because of the complexity, climate models are usually run on powerful computers.
The Very, Very Simple Climate Model is, as the name implies, very simple. In this model, average global temperature is determined entirely by the atmospheric carbon dioxide concentration via greenhouse warming of the atmosphere. The impacts of the Earth's biosphere, changes in land use, wind and precipitation patterns, other greenhouse gases, uptake of carbon dioxide by the oceans and other factors are not considered by this very simple model. Many of these factors decrease the amount of carbon dioxide in the atmosphere over time.
George E.P. Box once said, "all models are wrong, but some models are useful." The more a complex system like Earth is simplified in a model, the more wrong the model is. However, in simplifying this model to temperature and carbon dioxide, The Very, Very Simple Climate Model allows students to focus on the cause and effect relationships of greenhouse gases and climate change. A major educational point embodied in this model is that temperatures depend on concentration, which rises whenever emissions are greater than zero. When you hear world leaders saying that they are working hard to reduce the rate of growth of greenhouse gas emissions, remember that reducing the rate of growth does not lead to reduced temperatures. Instead, the amount of greenhouse gases continues to grow in the atmosphere whenever emissions are greater than zero.
The assumptions behind this model, though rather limited, are valid as far as they go. The starting values for concentration, emission rate, and temperature are right around actual values for the year 2000. The ranges for emission rate choices are in line with predictions scientists think we are likely to see in this Century. The relationship between atmospheric carbon dioxide concentration and temperature is well-established; basically, temperature rises about 3° C for each doubling of carbon dioxide concentration. So, for example, if the concentration goes from 400 ppmv to 800 ppmv, we expect to see temperature go up by 3° C.
According to the Intergovernmental Panel on Climate Change and their 2007 Assessment Report, Earth’s average temperature rose 0.6° Celsius (1.1°F) during the 20th Century. Based on the results from about a dozen computer models, the IPCC projects that global warming will continue. Model results project that Earth's average global temperature will rise between 1.8° and 4.0° Celsius (3.2° and 7.2° F) depending largely on how humans change the ways they live on the planet.
RELATED SECTIONS OF THE WINDOWS TO THE UNIVERSE WEBSITE:
- What Is a Climate Model?.
- How Climate Models Work
- Accuracy and Uncertainty in Climate Models
- Global Warming: Scientists Say Earth Is Heating Up
- Tackling the Global Warming Challenge
- The Intergovernmental Panel on Climate Change
- The Carbon Cycle Game
- Using the Carbon Cycle Interactive Game in the Classroom
- Carbon Dioxide: Sources and Sinks
- Carbon Dioxide
- What Is "Carbon Neutral"?
Kwa kutumia mfano rahisi wa mtandaoni, wanafunzi hujifunza juu ya uhusiano kati ya wastani wa joto la dunia na uzalishaji wa kaboni dioksidi wakati wa kutabiri mabadiliko ya joto katika karne ya 21. Mfano wa hali ya hewa ya maingiliano iliyoundwa na Randy Russell. Mwongozo kwa ajili ya walimu maendeleo na Lisa Gardiner. Matokeo ya Kujifunza ya Wanafunzi: _ Kompyuta ya maingiliano pamoja na tathmini ya hiari - Waulize wanafunzi nini wamesikia kuhusu mabadiliko ya hali ya hewa ya baadaye kutoka kwa magazeti, mtandao, na televisheni. Ikiwa wakati unaruhusu, waombe wanafunzi wapate na kisha washiriki makala kuhusu mabadiliko ya hali ya hewa ya wakati ujao. Gesi za chafu, kama vile kaboni dioksidi, zinazotolewa katika angahewa, ni, kwa sehemu kubwa, kusababisha mabadiliko ya hali ya hewa ya hivi karibuni. Ukurasa wa Windows to the Universe wenye kichwa Global Warming: Scientists Say Earth Is Heating Up hutoa muhtasari. - Waambie wanafunzi kwamba mifano hutumiwa kutabiri jinsi hali ya hewa ya Dunia itakavyobadilika wakati ujao. Kwa ujumla, mfano wa kompyuta hutumia hesabu kueleza jinsi Dunia inavyofanya kazi. Je, wanafunzi wamesoma ukurasa wa Windows to the Universe wenye kichwa What Is a Climate Model? Na kisha kujadili nini mifano ni. "Kama unavyojifunza katika masomo haya, unaweza kusoma ""Jinsi Models ya Hali ya Hewa Kazi"" na ""Ukweli na Uncertainty katika Models ya Hali ya Hewa.""" Mazoezi: Sehemu ya 1 - Kujifunza jinsi mfano unavyofanya kazi - Waambie wanafunzi kwamba watatumia mfano wa mtihani wa hali ya hewa na hali ya hewa katika karne hii kulingana na kiasi cha kaboni dioksidi iliyotolewa katika anga. - familiarize wanafunzi na mhimili wa grafu ambapo data kutoka kila mfano kukimbia itakuwa plot (tazama takwimu hapa chini.) Mhimili wa x unaonyesha miaka katika siku zijazo. Mhimili wa y una vipimo vitatu tofauti: (1) kiwango cha uzalishaji wa kaboni dioksidi, (2) mkusanyiko wa kaboni dioksidi, na (3) wastani wa joto la dunia. - Kuanzisha vigezo kwa upande wa kushoto wa grafu (tazama picha hapa chini) kwamba wanafunzi wanaweza kudhibiti kama wao kukimbia mfano. Kiwango cha uzalishaji wa kaboni dioksidi hupimwa katika gigatons ya kaboni dioksidi kwa mwaka. Kulingana na kiwango cha ujuzi wa hesabu ya wanafunzi wako, unaweza kutaka kuanzisha dhana ya kiwango katika hatua hii. "Mfano: ""Ni nini kitatokea kwa joto la dunia wakati ujao ikiwa kila mwaka tungetoa kiasi sawa cha kaboni dioksidi katika angahewa kama tulivyofanya mwaka 2000?""" Kiwango hicho kilikuwa karibu gigatons 6 za kaboni kwa mwaka. "Kama ilivyoelezwa hapo juu, kiwango cha uzalishaji wa kaboni dioksidi kinapaswa kuwa ""6 gigatons"" (kwa kawaida ni 6)." "Kuwa na uwezo wa kuweka ""Urefu wa hatua ya muda"" kwa miaka 10 kwa kutumia orodha ya pop-up." Hii inamaanisha kwamba kila wakati wanapoambia mfano wa kusonga mbele, utaendelea miaka 10 ya "wakati wa mfano." "Kisha, wanafunzi wanapaswa kubonyeza kitufe cha ""Kwenda mbele"" mara kumi ili kupata data ya karne ya 21." Kila mara wanapobonyeza kifungo pointi tatu zitaonekana kwenye grafu. Rangi ya pointi hizi inahusiana na rangi ya vipimo vitatu vya mhimili wa y. (Picha iliyo juu inaonyesha grafu inayotokana na hilo.) - Zungumza kama darasa kile grafu hii inaonyesha. - Dots bluu (kiwango cha uzalishaji) kuwakilisha kiasi cha kaboni sisi kuongeza kwa anga kila mwaka. Tangu kiwango alibaki sawa kwa ajili ya mtindo huu kukimbia, dots bluu kuunda mstari wa usawa juu ya grafu. - Dots nyeusi kuwakilisha kiasi cha kaboni imehifadhiwa katika anga kwa muda. Vipimo ni "sehemu kwa milioni kwa kiasi" (ppmv). Kwa mfano, kiwango cha juu cha viwango vya maambukizi ya dawa ya kulevya ni 368 ppm (ppm) kwa mwaka wa 2000. Katika kipindi hiki, mkusanyiko wa kemikali huongezeka kutoka karibu 400 ppmv hadi zaidi ya 600 ppmv kufikia mwaka 2100. - Dots nyekundu kuwakilisha wastani wa joto la dunia katika digrii Celsius. Kwa mfano, kiwango cha joto cha joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto la joto. Katika kipindi hiki cha mfano, joto liliongezeka kwa kasi hadi 17.5 ° C kufikia mwaka 2100. Katika mfano huu rahisi, joto huamuliwa kabisa na mkusanyiko wa CO2 ya angahewa kupitia joto la chafu la angahewa. Mazoezi ya kuingiliana: Sehemu ya 2 - Kujaribu hali tofauti za mabadiliko ya hali ya hewa - Waulize wanafunzi ikiwa wanafikiri kukimbia kwa mfano wa kwanza kutaonyesha watu watafanya nini katika karne ya 21. Vitendo vya wanadamu ni jambo kubwa zaidi lisilojulikana linapokuja mabadiliko ya hali ya hewa ya baadaye. Uchunguzi wa maoni ya wanafunzi: Je, tutatoa kiasi hicho cha kaboni dioksidi katika angahewa kama tunavyofanya sasa? Je, tutatoa kiasi kidogo zaidi? Je, tutaachilia zaidi? - Brainstorm jinsi na kwa nini uzalishaji wa kaboni inaweza kubadilika katika siku zijazo. Kwa mfano, uzalishaji wa kaboni utaongezeka ikiwa mitambo zaidi ya umeme itaundwa ambayo huchoma mafuta ya visukuku, lakini uzalishaji wa kaboni utapungua ikiwa teknolojia zaidi zitabuniwa ambazo hupunguza matumizi ya mafuta ya visukuku. - Kulingana na uchunguzi na brainstorms, kuwa na wanafunzi kazi katika makundi kuja na hali kwamba wangependa mtihani. Kwa mfano, uzalishaji wa kaboni dioksidi uliongezeka katika karne ya 21 na kisha ulipungua. Kwa kweli, kwa kweli, kwa kweli, kwa kweli, kwa kweli, kwa kweli, kwa kweli, kwa kweli, kwa sababu ya kiwango cha uzalishaji wa GtC, ambayo ni kiwango cha juu cha kiwango cha juu cha kiwango cha juu cha kiwango cha juu cha kiwango cha juu cha kiwango cha juu cha kiwango cha juu cha kiwango cha juu cha kiwango cha juu cha kiwango cha juu cha kiwango cha juu. Ili kuwasaidia wanafunzi kuzingatia wakati wao kukimbia mfano, kuwa na makundi ya wanafunzi kuandika nje ya hali yao katika kifungu kabla ya kuanza. - Ili kuweka upya mfano ili iweze kuendeshwa tena, waambie wanafunzi kubonyeza kitufe cha "Reload" au "Refresh" kwenye vivinjari vyao vya wavuti. Waulize wanafunzi kuweka hatua ya muda kama miaka 10 kama walivyofanya hapo awali. "Kujaribu kuamua kiwango cha uzalishaji wa CO2 katika kipindi cha karne ya 20 kwa kubadili kiwango cha uzalishaji, kubonyeza ""Hatua ya mbele,"" na kisha kubadili kiwango cha uzalishaji tena." Kwa mfano, ikiwa ungeamua kuongeza uzalishaji kwa nusu ya kwanza ya karne na kisha kuupunguza kwa nusu ya mwisho, ungehitaji kuongeza kiwango kwa kila hatua ya muda kwa miaka 50 ya kwanza na kisha kupunguza kiwango kwa kila hatua ya muda kwa miaka 50 ya mwisho. - Zungumzia kama darasa matokeo ya matukio mbalimbali ya wanafunzi: Ni nini kilichotokea kwa joto na viwango vya kaboni dioksidi kwa muda? Je, ongezeko fulani la joto duniani linaweza kuepukwa? Ni hali gani iliyokuwa na ongezeko la joto kidogo zaidi? Ni ipi iliyokuwa na idadi kubwa zaidi? Wanafunzi (au makundi ya wanafunzi) wanaweza kuwasilisha matokeo yao kutoka sehemu ya 2 kwa wengine wa darasa katika ripoti ya mdomo, mabango, au slides za PowerPoint. Wanafunzi wanaweza kufanya majaribio kwa kutumia mfano rahisi sana wa hali ya hewa, na kujaribu kama kuna tofauti katika joto la dunia kati ya matukio mawili. "Wanafunzi wa shule ya sekondari walichagua ""Kushughulikia changamoto ya ongezeko la joto duniani"" na ""Mvutano wa mawazo"" ili kuamua jinsi ya kupunguza kiasi cha gesi zinazosababisha joto duniani." "Kujumuisha shughuli hii na ""Carbon dioxide: vyanzo na sinks"" na ""Carbon Cycle Game"" ili kuendeleza uelewa wa wanafunzi wa wapi kaboni dioksidi ya angahewa inakuja, ni wapi inakwenda, na ni muda gani inabaki katika angahewa." Wanasayansi wa hali ya hewa hutumia mifano ili kuelewa jinsi Dunia inavyobadilika. Mifano ya Dunia inaweza majaribio juu ya kutathmini athari za usumbufu mbalimbali juu ya sayari. Mifano ya hali ya hewa hufafanua sayari yetu kwa kutumia hesabu za hisabati. Kwa sababu Dunia ni tata, inahitaji mamia ya equations tata sana kuiga angahewa, bahari, na uso wa nchi kavu. Kwa sababu ya utata wake, kwa kawaida mifano ya hali ya hewa huendeshwa kwenye kompyuta zenye nguvu. Mfano wa Hali ya Hewa rahisi sana, kama jina linavyodokeza, ni rahisi sana. Katika mfano huu, wastani wa joto la dunia huamuliwa kabisa na mkusanyiko wa kaboni dioksidi katika angahewa kupitia joto la chafu la angahewa. Mabadiliko ya mazingira ya dunia, mabadiliko ya matumizi ya ardhi, upepo na mifumo ya mvua, gesi nyingine za chafu, kuchukua kaboni dioksidi na bahari na mambo mengine hayafikiriwa na mfano huu rahisi sana. Sababu nyingi kati ya hizo hupunguza kiasi cha kaboni dioksidi katika angahewa kwa muda. George E. P. Box aliwahi kusema, "mifano yote ni makosa, lakini baadhi ya mifano ni muhimu". Kadiri mfumo tata kama Dunia unavyofupishwa katika mfano, ndivyo mfano huo unavyofanya makosa zaidi. Hata hivyo, katika kurahisisha mfano huu kwa joto na kaboni dioksidi, The Very, Very Simple Hali ya Hewa Model inaruhusu wanafunzi kuzingatia sababu na athari mahusiano ya gesi chafu na mabadiliko ya hali ya hewa. "Kitu muhimu cha elimu kilichojumuishwa katika mfano huu ni kwamba joto hutegemea mkusanyiko, ambao huongezeka wakati wowote uzalishaji ni mkubwa kuliko sifuri. """ "Wakati unawasikia viongozi wa dunia wakisema kwamba wanafanya kazi kwa bidii kupunguza kiwango cha ongezeko la uzalishaji wa gesi za chafu, kumbuka kwamba kupunguza kiwango cha ongezeko hakusababisha joto kupungua. """ Kwa sababu hiyo, kiasi cha gesi zinazosababisha madhara ya chafu katika anga huongezeka kila wakati ambapo kiwango cha gesi zinazosababisha madhara ya chafu kinapozidi kiwango cha sifuri. Dhana nyuma ya mfano huu, ingawa ni mdogo, ni halali mbali kama wao kwenda. Kiwango cha msingi cha viwango vya joto, kiwango cha uzalishaji na kiwango cha joto ni sawa na viwango vya kweli vya mwaka wa 2000. """Vipimo vya viwango vya uzalishaji vinaambatana na utabiri wa wanasayansi ambao tunadhani tunaweza kuona katika karne hii." Uhusiano kati ya joto na kiwango cha kaboni dioksidi katika angahewa umethibitishwa vizuri, kwa mfano, joto huongezeka kwa karibu 3 ° C kwa kila marudio ya kiwango cha kaboni dioksidi. "Kwa mfano, ikiwa kiwango cha joto cha dunia kinazidi kutoka 400 ppm hadi 800 ppm, inatarajiwa kuongezeka kwa joto kwa 3 ° C. Kulingana na Intergovernmental Panel on Climate Change (IPCC), joto la wastani la dunia liliongezeka kwa 0.6 ° C katika karne ya 20.""" Kulingana na matokeo ya mifano kadhaa ya kompyuta, IPCC inakadiria kwamba ongezeko la joto duniani litaendelea. Matokeo ya utafiti huo yanaonyesha kuwa joto la dunia la wastani litapanda kati ya 1.8 ° C na 4.0 ° C, ikitegemea jinsi wanadamu wanavyofanya mabadiliko katika maisha yao. Sehemu zinazohusiana na tovuti ya The WINDOWS TO THE UNIVERSE: - Ni nini mfano wa hali ya hewa?. "Kama mfano wa hali ya hewa, ""Mchanganyiko wa Carbon dioxide"" ni mchezo wa kuvutia wa ""Carbon Cycle Game"" na ""Carbon dioxide: Sources and Sinks"" na ""Carbon dioxide: What is Carbon Neutral?"""