query: For decades, most scientists saw climate change as a distant prospect.

positive: Climate change (general concept) Climate variability includes all the variations in the climate that last longer than individual weather events, whereas the term climate change only refers to those variations that persist for a longer period of time, typically decades or more. In the time since the industrial revolution the climate has increasingly been affected by human activities that are causing global warming and climate change.The climate system receives nearly all of its energy from the sun. The climate system also radiates energy to outer space. The balance of incoming and outgoing energy, and the passage of the energy through the climate system, determines Earth\'s energy budget. When the incoming energy is greater than the outgoing energy, earth\'s energy budget is positive and the climate system is warming. If more energy goes out, the energy budget is negative and earth experiences cooling.\nThe energy moving through Earth\'s climate system finds expression in weather, varying on geographic scales and time. Long-term averages and variability of weather in a region constitute the region\'s climate. Such changes can be the result of "internal variability", when natural processes inherent to the various parts of the climate system alter the distribution of energy. Examples include variability in ocean basins such as the Pacific decadal oscillation and Atlantic multidecadal oscillation. Climate variability can also result from external forcing, when events outside of the climate system\'s components nonetheless produce changes within the system. Examples include changes in solar output and volcanism.\nClimate variability has consequences for sea level changes, plant life, and mass extinctions; it also affects human societies.

positive: Scientific consensus on climate change There is currently a strong scientific consensus that the Earth is warming and that this warming is mainly caused by human activities. This consensus is supported by various studies of scientists' opinions and by position statements of scientific organizations, many of which explicitly agree with the Intergovernmental Panel on Climate Change (IPCC) synthesis reports.  Nearly all actively publishing climate scientists (97–98%) support the consensus on anthropogenic climate change, and the remaining 2% of contrarian studies either cannot be replicated or contain errors.

positive: Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years .   In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing .   Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years .   Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) ,  whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change .   Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .

negative: Bali Declaration by Climate Scientists The 2007 Bali Declaration by Climate Scientists was a statement signed by over 200 climate scientists advocating specific targets for greenhouse gas emissions for the 21st century . The statement was based on the United Nations Framework Convention on Climate Change Article 2 that committed signatories to the '' ... stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system '' and on the science available in the Intergovernmental Panel on Climate Change Fourth Assessment report ( IPCC AR4 ) . The Bali Declaration was released to coincide with the 2007 United Nations Climate Change Conference which took place in Bali 3 -- 15 December 2007 .   Category : Climate change policy

negative: Climate change in Bangladesh Climate Change in Bangladesh is an extremely crucial issue and according to National Geographic , Bangladesh ranks first as the nation most vulnerable to the impacts of Climate Change in the coming decades .

negative: Andrew Dessler Andrew Emory Dessler ( born 1964 ) is a climate scientist and Professor of Atmospheric Sciences at Texas A&M University . His research subject areas are atmospheric chemistry , climate change and climate change policy .

negative: List of climate scientists This list of climate scientists contains famous or otherwise notable persons who have contributed to the study of climate science . The list is compiled manually so will not be complete or up to date . See also : Category : Climatologists and List of authors of Climate Change 2007 : The Physical Science Basis .  The list includes scientists from several specialities or disciplines .

negative: Climate change in South Korea In recent decades most countries have been experiencing huge industrial progress . Urban and industrial areas in South Korea also had fast development from 1960s to 1980s . Industrialization and the increase in population have produced various pollutants and greenhouse gases , which are anthropogenic factors for climate change . South Korea is experiencing changes in climate parameters , including annual temperature , rainfall amounts , and precipitation . The most distinct climate change predicted for South Korea is an increase in the range of temperature fluctuation throughout the four seasons . The number of record minimum temperature days has decreased rapidly , and maximum precipitation during the summer has increased . Ongoing global climate change has produced local climate changes and extreme weather that affects : social , economy , industry , culture , and many other sectors . The increased possibility for new types of strong weather damage evokes the seriousness and the urgency of climate change . To quickly adapt to climate change , the South Korean government began an effort to reduce greenhouse gas emissions , and is one step closer to having a low-carbon based socio-economic nation .

negative: John F. B. Mitchell John Francis Brake Mitchell OBE FRS ( born 7 October 1948 ) is a British climatologist and climate modeller .   He studied Applied Mathematics at Queen 's University Belfast in 1970 , staying on to gain a PhD in Theoretical Physics in 1973 .   In 1978 , he was appointed head of the Climate Change group in what is now the Met Office 's Hadley Centre for Climate Prediction and Research . He was Chief Scientist from 2002 to 2008 and Director of Climate Science from 2008 to 2010 . He is the most cited scientist regarding the topic of global warming .   He was a convening lead author for the first and third IPCC Working Group I reports and lead author for the second . He was also chair of the World Meteorological Organization JSC/CLIVAR Working Group on Climate Modelling and a member of WMO Executive Council from 2005 to 2008 .   He now ( 2014 ) works part-time as Principal Research Fellow , advising the Met Office Chief Scientist on climate change and is Visiting Professor at the University of Reading .

negative: Venkatachalam Ramaswamy Venkatachalam Ramaswamy ( V. `` Ram '' Ramaswamy ) is the Director of the Geophysical Fluid Dynamics Laboratory of the National Oceanic and Atmospheric Administration ( NOAA ) Office of Oceanic and Atmospheric Research ( OAR ) , studying climate modeling and climate change . `` A leading climate scientist '' , his work is cited as supporting evidence for significant stratospheric climate change . He focuses in particular on radiative transfer models and the hydrologic cycle in the atmosphere . He has actively supported the development of supercomputing approaches that enable researchers to achieve higher resolution and greater complexity in climate models . As a lead author involved in the Intergovernmental Panel on Climate Change ( IPCC ) , Ramaswamy 's contributions ( along with the contributions of many scientists ) was recognised by the joint award of the 2007 Nobel Peace Prize to the IPCC .

negative: Corinne Le Quéré Corinne Le Quéré FRS ( born July 1966 ) is a Franco-Canadian scientist . She is Professor of Climate Change Science and Policy at the University of East Anglia and Director of Tyndall Centre for Climate Change Research .

negative: Drawdown (climate) Climate drawdown is the point at which greenhouse gas concentrations in the atmosphere begin to decline on a year-to-year basis .   Drawdown is a goal for reversing climate change , and eventually reducing global average temperatures .   Project Drawdown is a climate change mitigation project initiated by Paul Hawken and climate activist Amanda Joy Ravenhill . Central to the project is the compilation of a list of the `` 100 most substantive solutions to global warming . '' The list , encompassing only technologically viable , existing solutions , was compiled by a team of over 200 scholars , scientists , policymakers , business leaders and activists ; for each solution the carbon impact through the year 2050 , the total and net cost to society , and the total lifetime savings were measured and modelled .

negative: Anders Levermann Anders Levermann is a climate scientist at the Potsdam Institute for Climate Impact Research and Columbia University . He is a Professor of the Dynamics of the Climate System at Institute for Physics and Astrophysics of the Potsdam University , Germany . He was a lead author of the chapter on sea-level changes of the fifth assessment report of the Intergovernmental Panel on Climate Change ( IPCC AR5 ) , and contributed to the paleoclimate chapter in the previous report ( IPCC-AR4 ) . Levermann advises political and economic stakeholders on the issue of climate change .

negative: Robert Jay Charlson Robert Jay Charlson is an American atmospheric scientist , climate scientist , pioneer in the fields of climate forcing and climate change , and coauthor of the CLAW hypothesis . He is professor of Atmospheric Sciences , chemistry , and geophysics at the University of Washington in Seattle , Washington . Charlson earned his PhD from the University of Washington . He is a world expert in atmospheric chemistry , aerosol physics , aerosol/cloud/climate interaction , aerosol and cloud instrumentation .

negative: Reto Knutti Reto Knutti ( born 1973 ) is a Swiss climate scientist and professor of climate physics at ETH Zurich 's Institute for Atmospheric and Climate Science . He is known for his research involving climate models , and has been a key member of the Intergovernmental Panel on Climate Change .

negative: List of scientists opposing the mainstream scientific assessment of global warming This is a list of scientists who have made statements that conflict with the scientific consensus on global warming as summarized by the Intergovernmental Panel on Climate Change and endorsed by other scientific bodies . As approximately 97 % of publishing climate scientists support the consensus on anthropogenic climate change , this list represents a minority viewpoint .   The scientific consensus is that the global average surface temperature has risen over the last century . Scientific opinion on climate change was summarized in the 2001 Third Assessment Report of the Intergovernmental Panel on Climate Change ( IPCC ) . The main conclusions on global warming at that time were as follows :  The global average surface temperature has risen 0.6 ± 0.2 ° C since the late 19th century , and 0.17 ° C per decade in the last 30 years .  `` There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities '' , in particular emissions of the greenhouse gases carbon dioxide and methane .  If greenhouse gas emissions continue the warming will also continue , with temperatures projected to increase by 1.4 ° C to 5.8 ° C between 1990 and 2100 . Accompanying this temperature increase will be increases in some types of extreme weather and a projected sea level rise . The balance of impacts of global warming become significantly negative at larger values of warming .   These findings are recognized by the national science academies of all the major industrialized nations ; the consensus has strengthened over time and is now virtually unanimous . The level of consensus correlates with expertise in climate science .   There have been several efforts to compile lists of dissenting scientists , including a 2008 US senate minority report , the Oregon Petition , and a 2007 list by the Heartland Institute , all three of which have been criticized on a number of grounds .   For the purpose of this list , a `` scientist '' is defined as an individual who has published at least one peer-reviewed research article in the broad field of natural sciences , although not necessarily in a field relevant to climatology . Since the publication of the IPCC Third Assessment Report , each has made a clear statement in his or her own words ( as opposed to the name being found on a petition , etc. ) disagreeing with one or more of the report 's three main conclusions . Their views on climate change are usually described in more detail in their biographical articles . Few of the statements in the references for this list are part of the peer-reviewed scientific literature ; most are from other sources such as interviews , opinion pieces , online essays and presentations .   NB : Only individuals who have their own Wikipedia article may be included in the list .

negative: Kevin Anderson (scientist) Kevin Anderson is the Deputy Director of the Tyndall Centre for Climate Change Research ; holds a joint chair in Energy and Climate Change at the School of Mechanical , Aerospace and Civil Engineering at the University of Manchester and School of Environmental Sciences at the University of East Anglia ; and is an honorary lecturer in Environmental Management at the Manchester Business School . He is an adviser to the British Government ( as of 2009 ) on climate change .

negative: David Reay David S. Reay is a climate change scientist , author , and professor of carbon management at the University of Edinburgh .

negative: Helen Cleugh Helen A. Cleugh is an atmospheric scientist . She is currently the Chief Research Scientist in Commonwealth Scientific and Industrial Research Organisation ( CSIRO ) ( Oceans and Atmosphere ) where she leads the Earth Systems and Climate Change Hub .   Cleugh 's research focuses on observing and predicting atmospheric , climate and marine systems and determining how they interact with human activities .

negative: Copernicus Climate Change Service (C3S) The Copernicus Climate Change Service ( C3S ) is one of the six thematic services provided by the European Union 's Copernicus Programme . The Copernicus Programme is managed by the European Commission and the C3S is implemented by the European Centre for Medium-Range Weather Forecasts ( ECMWF ) and is expected to become operational in 2018 .   The objective of the Copernicus Climate Change Service is to build an EU knowledge base in support of mitigation and adaptation policies for Climate Change and Global Warming . The goal of the operational Climate Change service is to provide reliable information about the current and past state of the climate , the forecasts on a seasonal time scale , and the more likely projections in the coming decades for various scenarios of greenhouse gas emissions and other Climate Change contributors .

negative: Laboratoire des sciences du climat et de l'environnement The Laboratoire des sciences du climat et de l'environnement ( LSCE , Climate and Environment Sciences Laboratory ) is a laboratory for the study of climate and in particular climate change . It plays a very important role within the framework of the Intergovernmental Panel on Climate Change , which involves many of its researchers . It is very diversified because it includes modellers like experimenters , glaciologists as specialists in remote sensing or air quality study .   The climate scientist Valerie Masson-Delmotte is involved in the laboratory .

negative: John Christy John Raymond Christy is a climate scientist at the University of Alabama in Huntsville ( UAH ) whose chief interests are satellite remote sensing of global climate and global climate change . He is best known , jointly with Roy Spencer , for the first successful development of a satellite temperature record .

negative: Climate change in Pakistan Pakistan makes a tiny contribution to total global greenhouse gas ( GHG ) emissions , less than 1 % ( among the lowest in the world ) but it is among the countries most vulnerable to climate change , and it has very low technical and financial capacity to adapt to its adverse impacts .  The effects of climate change and global warming on Pakistan , the melting of glaciers in the Himalayas , threatening the volumetric flow rate of many of the most important rivers of Pakistan . In Pakistan , such effects are projected to impact millions of lives . As a result of ongoing climate change , the climate of Pakistan has become increasingly volatile over the past several decades ; this trend is expected to continue .   Climate Change Mitigation Pakistan 's greenhouse gas ( GHG ) emissions are low compared to international standards . In 2008 Pakistan 's total GHG emissions were 310 million tons of CO2 equivalent . These comprised : CO2 54 % ; Methane ( CH4 ) 36 % ; Nitrous Oxide ( N2O ) 9 % ; Carbon Monoxide ( CO ) 0.7 % ; and Non-Methane Volatile Organic Compounds 0.3 % . ( Source : National GHG inventory 2008 ) . The energy sector is the single largest source of GHG emission in Pakistan ; it accounts for nearly 51 % of these emissions and is followed by the agriculture sector ( 39 % ) , industrial processes ( 6 % ) , land use , land use change and forestry ( LULUCF ) ( 3 % ) emissions and waste ( 1 % ) ( Source : National GHG inventory 2008 ) . As such , the most important targets for mitigation efforts focused on reduction of GHG emissions are the energy and agriculture sectors . In the energy sector , integration of climate change and energy policy objectives is particularly important as today 's investment will `` lock in '' the infrastructure , fuel and technologies to be used for decades to come . Similarly , the building and transport infrastructure put in place today should meet the design needs of the future . Therefore , greater attention must be paid to energy efficiency requirements in building codes and long-term transport planning .

negative: Valerie Masson-Delmotte Valerie Masson-Delmotte is a French climate scientist and Research Director at the French Alternative Energies and Atomic Energy Commission , where she works in the Climate and Environment Sciences Laboratory ( LSCE ) . She uses data from past climates to test models of climate change , and has contributed to several IPCC reports .

negative: James Croll James Croll , FRS , ( 2 January 1821 -- 15 December 1890 ) was a 19th-century Scottish scientist who developed a theory of climate change based on changes in the Earth 's orbit .

negative: Prem Chand Pandey Prem Chand Pandey is an Indian scientist and academic in the fields of Satellite Oceanography , Remote Sensing , Atmospheric Science , Antarctic and Climate Change

negative: Climatic Research Unit The Climatic Research Unit ( CRU ) is a component of the University of East Anglia and is one of the leading institutions concerned with the study of natural and anthropogenic climate change .   With a staff of some thirty research scientists and students , the CRU has contributed to the development of a number of the data sets widely used in climate research , including one of the global temperature records used to monitor the state of the climate system , as well as statistical software packages and climate models .

negative: United States temperature extremes For the United States , the extremes are 134 F in Death Valley , California in 1913 and -79.8 F recorded in Prospect Creek , Alaska in 1971 .   The largest recorded temperature change in one place over a 24-hour period occurred on January 15 , 1972 in Loma , Montana , when the temperature rose from -54 to .   The most dramatic temperature changes occur in North American climates susceptible to Chinook winds . For example , the largest 2-minute temperature change of 49 F-change occurred in Spearfish , South Dakota , a rise from -4 to .

negative: Homogenization (climate) Homogenization in climate research means the removal of non-climatic changes . Next to changes in the climate itself , raw climate records also contain non-climatic jumps and changes for example due to relocations or changes in instrumentation . The most used principle to remove these inhomogeneities is the relative homogenization approach in which a candidate stations is compared to a reference time series based on one or more neighboring stations . The candidate and reference station ( s ) experience about the same climate , non-climatic changes that happen only in one station can thus be identified and removed .

negative: Peter Sinclair (environmental activist) Peter Sinclair from Midland , Michigan ( born 1953 ) , is an environmental activist whose focus is on climate change . He is a YouTube blogger , explorer and founder of the ClimateCrocks.com website . Together with climate researchers he 's traveled to hot spots of climate change , for instance to Greenland as part of the Dark Snow Project . Sinclair is perhaps best known for producing the Climate Denial Crock of the Week series on his YouTube channel . Videos have received praise from climate scientists such as Gavin Schmidt , Michael E. Mann , and the late Stephen Schneider . In 2012 , he launched another YouTube series , entitled This is not Cool , for the Yale Project on Climate Change Communication .

negative: Thin Ice (2013 film) Thin Ice is a 2013 documentary film following geologist Simon Lamb on a search to understand the science behind climate change . This is achieved by traveling the world and meeting a range of scientists , from biologists to physicists , who are investigating the climate . The film 's conclusion emphasises the scientific consensus on human-induced climate change .   The film was a joint initiative between Oxford University and Victoria University of Wellington , and premiered around the world on Earth Day 2012 , and in New Zealand in 2015 .

negative: David Karoly David John Karoly ( born 1955 ) is an Australian atmospheric scientist . He is an expert in climate change , stratospheric ozone depletion , and climate variations due to the El Niño-Southern Oscillation ( ENSO ) .   Karoly has served as a lead author for the Intergovernmental Panel on Climate Change ( IPCC ) Working Group 2 ( on societal impacts ) and he is a member of the faculty of the School of Earth Sciences at the University of Melbourne . His work , along with that of the many other lead authors and review editors , contributed to the award of the 2007 Nobel Peace Prize , which was won jointly by the IPCC and Al Gore . He is member of the board of the Climate Change Authority .

negative: Global Land Project The Global Land Project -LSB- changed to Global Land Programme in 2016 -RSB- is a research initiative of Future Earth ( originally the International Geosphere-Biosphere Programme ( IGBP ) and the International Human Dimensions Programme ( IHDP ) ) . It aims to understand the changes of the land systems given the prospects of rapid and massive global environmental change . The goal of GLP is `` to measure , model and understand the coupled human-environment system '' .   The Global Land Project Science Plan describes the scientific questions that the land systems research community considers to be crucial for the next decade . GLP has three objectives that determine the research framework :  To identify the agents , structures and nature of change in coupled human-environment systems on land , and to quantify their effects on the coupled system ;  To assess how the provision of ecosystem services is affected by the changes in ( i ) above ; and  To identify the character and dynamics of vulnerable and sustainable coupled human-environment systems to interacting perturbations , including climate change .

negative: Joel B. Smith Joel B. Smith is an expert on climate change policy .   He was a coordinating lead author of the Intergovernmental Panel on Climate Change 2001 assessment report and a lead author of the 2007 assessment report ( the work of the IPCC , including the contributions of many scientists , was recognised by the joint award of the 2007 Nobel Peace Prize ) .   He is currently a Principal at Stratus Consulting Inc. , in Boulder , CO. .

negative: Dennis L. Hartmann Dennis L Hartmann is an American atmospheric scientist at the University of Washington . He has done research on ozone depletion and climate change .   In 2016 he was elected to the National Academy of Sciences .


query: Rather than 100 years of unprecedented global warming as predicted by  IPCC, the global temperatures have leveled off and we seem to be heading  for cooler weather."

positive: Scientific consensus on climate change There is currently a strong scientific consensus that the Earth is warming and that this warming is mainly caused by human activities. This consensus is supported by various studies of scientists' opinions and by position statements of scientific organizations, many of which explicitly agree with the Intergovernmental Panel on Climate Change (IPCC) synthesis reports.  Nearly all actively publishing climate scientists (97–98%) support the consensus on anthropogenic climate change, and the remaining 2% of contrarian studies either cannot be replicated or contain errors.

positive: Intergovernmental Panel on Climate Change The Intergovernmental Panel on Climate Change ( IPCC ) is a scientific and intergovernmental body under the auspices of the United Nations , set up at the request of member governments , dedicated to the task of providing the world with an objective , scientific view of climate change and its political and economic impacts . It was first established in 1988 by two United Nations organizations , the World Meteorological Organization ( WMO ) and the United Nations Environment Programme ( UNEP ) , and later endorsed by the United Nations General Assembly through Resolution 43/53 . Membership of the IPCC is open to all members of the WMO and UNEP .  The IPCC produces reports that support the United Nations Framework Convention on Climate Change ( UNFCCC ) , which is the main international treaty on climate change . The ultimate objective of the UNFCCC is to `` stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic -LSB- i.e. , human-induced -RSB- interference with the climate system '' . IPCC reports cover `` the scientific , technical and socio-economic information relevant to understanding the scientific basis of risk of human-induced climate change , its potential impacts and options for adaptation and mitigation . ''   The IPCC does not carry out its own original research , nor does it do the work of monitoring climate or related phenomena itself . The IPCC bases its assessment on the published literature , which includes peer-reviewed and non-peer-reviewed sources .   Thousands of scientists and other experts contribute ( on a voluntary basis , without payment from the IPCC ) to writing and reviewing reports , which are then reviewed by governments . IPCC reports contain a `` Summary for Policymakers '' , which is subject to line-by-line approval by delegates from all participating governments . Typically this involves the governments of more than 120 countries .   The IPCC provides an internationally accepted authority on climate change , producing reports which have the agreement of leading climate scientists and the consensus of participating governments . The 2007 Nobel Peace Prize was shared , in equal parts , between the IPCC and Al Gore .

positive: Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years .   In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing .   Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years .   Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) ,  whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change .   Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .

negative: IPCC First Assessment Report The First Assessment Report ( FAR ) of the Intergovernmental Panel on Climate Change ( IPCC ) was completed in 1990 . It served as the basis of the United Nations Framework Convention on Climate Change ( UNFCCC ) .   The report was issued in three main sections , corresponding to the three Working Groups of scientists that the IPCC had established .   Working Group I : Scientific Assessment of Climate Change , edited by J.T. Houghton , G.J. Jenkins and J.J. Ephraums  Working Group II : Impacts Assessment of Climate Change , edited by W.J. McG . Tegart , G.W. Sheldon and D.C. Griffiths  Working Group III : The IPCC Response Strategies   Each section included a summary for policymakers . This format was followed in subsequent Assessment Reports .   The executive summary of the policymakers ' summary of the WG I report includes :   We are certain of the following : there is a natural greenhouse effect ... ; emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases : CO2 , methane , CFCs and nitrous oxide . These increases will enhance the greenhouse effect , resulting on average in an additional warming of the Earth 's surface . The main greenhouse gas , water vapour , will increase in response to global warming and further enhance it .  We calculate with confidence that : ... CO2 has been responsible for over half the enhanced greenhouse effect ; long-lived gases would require immediate reductions in emissions from human activities of over 60 % to stabilise their concentrations at today 's levels ...  Based on current models , we predict : under -LSB- BAU -RSB- increase of global mean temperature during the -LSB- 21st -RSB- century of about 0.3 oC per decade ( with an uncertainty range of 0.2 to 0.5 oC per decade ) ; this is greater than that seen over the past 10,000 years ; under other ... scenarios which assume progressively increasing levels of controls , rates of increase in global mean temperature of about 0.2 oC -LSB- to -RSB- about 0.1 oC per decade .  There are many uncertainties in our predictions particularly with regard to the timing , magnitude and regional patterns of climate change , due to our incomplete understanding of : sources and sinks of GHGs ; clouds ; oceans ; polar ice sheets .  Our judgement is that : global mean surface air temperature has increased by 0.3 to 0.6 oC over the last 100 years ... ; The size of this warming is broadly consistent with predictions of climate models , but it is also of the same magnitude as natural climate variability . Thus the observed increase could be largely due to this natural variability ; alternatively this variability and other human factors could have offset a still larger human-induced greenhouse warming . The unequivocal detection of the enhanced greenhouse effect is not likely for a decade or more .  under the IPCC business as usual emissions scenario , an average rate of global mean sea level rise of about 6 cm per decade over the next century ( with an uncertainty range of 3 -- 10 cm per decade ) , mainly due to thermal expansion of the oceans and the melting of some land ice . The predicted rise is about 20 cm ... by 2030 , and 65 cm by the end of the next century .

negative: Global warming hiatus A global warming hiatus , also sometimes referred to as a global warming pause or a global warming slowdown , is a period of relatively little change in globally averaged surface temperatures . In the current episode of global warming many such 15-year periods appear in the surface temperature record , along with robust evidence of the long-term warming trend ; climate is classically averaged over 30-year periods .   Publicity has surrounded claims of a global warming hiatus during the period 1998 -- 2013 . The exceptionally warm El Niño year of 1998 was an outlier from the continuing temperature trend , and so subsequent annual temperatures gave the appearance of a hiatus : by January 2006 , it appeared to some that global warming had stopped or paused . A 2009 study showed that decades without warming were not exceptional , and in 2011 a study showed that if allowances were made for known variability , the rising temperature trend continued unabated . There was increased public interest in 2013 in the run-up to publication of the IPCC Fifth Assessment Report , and despite concerns that a 15-year period was too short to determine a meaningful trend , the IPCC included a section on a hiatus , which it defined as a much smaller increasing linear trend over the 15 years from 1998 to 2012 , than over the 60 years from 1951 to 2012 . Various studies examined possible causes of the short-term slowdown . Even though the overall climate system has continued to accumulate energy due to Earth 's positive energy budget , the available temperature readings at the Earth 's surface indicate slower rates of increase in surface warming than in the prior decade . Since measurements at the top of the atmosphere show that Earth is receiving more energy than it is radiating back into space , the retained energy should be producing warming in the Earth 's climate system .   Research reported in July 2015 on an updated NOAA dataset casts doubt on the existence of a hiatus , and it finds no indication of a slowdown even in earlier years . Scientists working on other datasets welcomed this study , though they have expressed the view that the recent warming trend was less than in previous periods of the same length . Subsequently , a detailed study supports the conclusion that warming is continuing , but it also find there was less warming between 2001 and 2010 than climate models had predicted , and that this slowdown might be attributed to short-term variations in the Pacific decadal oscillation ( PDO ) , which was negative during that period . Another review finds `` no substantive evidence '' of a pause in global warming . A statistical study of global temperature data since 1970 concludes that the term ` hiatus ' or ` pause ' is not justified .   Independent of these discussions about data and measurements for earlier years , 2015 turned out to be much warmer than any of the earlier years , already before El Niño conditions started . The warmth of 2015 largely ended any remaining scientific credibility of claims that the supposed `` hiatus '' since 1998 had any significance for the long-term warming trend . In January 2017 , a study published in the journal Science Advances cast further doubt on the existence of a recent pause , with more evidence that ocean temperatures have been underestimated . An April 2017 study found the data consistent with a steady warming trend globally since the 1970s , with fluctuations within the expected range of short term variability .

negative: Hurricane Katrina and global warming The tremendous destruction caused by recent Atlantic Ocean tropical cyclones , such as Hurricanes Katrina , Wilma , and Sandy caused a substantial upsurge in interest in the subject of global warming by news media and the wider public , and concerns that global climatic change may have played a significant role in those events . Time Magazine , for example , published an article titled , `` Is Global Warming Fueling Katrina ? '' -- however , the article itself addressed hurricanes in general , rather than Katrina specifically , and was inconclusive .   Shortly after the hurricane , former Boston Globe reporter Ross Gelbspan wrote an op-ed piece for the Globe titled , `` Katrina 's Real Name '' , declaring that the hurricane 's `` real name is global warming . '' Gelbspan went on to assert :  `` Although Katrina began as a relatively small hurricane that glanced off south Florida , it was supercharged with extraordinary intensity by the relatively blistering sea surface temperatures in the Gulf of Mexico . ''  Gelbspan did not single out Katrina from other recent storms in that regard ; in the article he went on to attribute other major weather events over the preceding year to global warming , including a blizzard in Los Angeles , high winds in Scandinavia , wildfires in Spain , and a drought centered in Missouri .   Britain 's then deputy prime minister , John Prescott , has linked Katrina with global warming , and statements made shortly after the hurricane by Germany 's environment minister , Jürgen Trittin , indicate he believes that global warming is responsible for an increase in the frequency of destructive natural events .   Kerry Emanuel had recently published a paper in the journal Nature that found a good correlation between hurricane intensity and sea surface temperatures . Some journalists have claimed Emanuel 's paper concludes that the recent increase in intense Atlantic storms is due to global warming , but Emanuel stated that `` it would be absurd to attribute the Katrina disaster to global warming '' .   The Internet blog RealClimate has written that `` there is no way to prove that Katrina either was , or was not , affected by global warming '' .

negative: Effects of global warming on oceans Global warming can affect sea levels , coastlines , ocean acidification , ocean currents , seawater , sea surface temperatures , tides , the sea floor , weather , and trigger several changes in ocean bio-geochemistry ; all of these affect the functioning of a society .

negative: List of scientists opposing the mainstream scientific assessment of global warming This is a list of scientists who have made statements that conflict with the scientific consensus on global warming as summarized by the Intergovernmental Panel on Climate Change and endorsed by other scientific bodies . As approximately 97 % of publishing climate scientists support the consensus on anthropogenic climate change , this list represents a minority viewpoint .   The scientific consensus is that the global average surface temperature has risen over the last century . Scientific opinion on climate change was summarized in the 2001 Third Assessment Report of the Intergovernmental Panel on Climate Change ( IPCC ) . The main conclusions on global warming at that time were as follows :  The global average surface temperature has risen 0.6 ± 0.2 ° C since the late 19th century , and 0.17 ° C per decade in the last 30 years .  `` There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities '' , in particular emissions of the greenhouse gases carbon dioxide and methane .  If greenhouse gas emissions continue the warming will also continue , with temperatures projected to increase by 1.4 ° C to 5.8 ° C between 1990 and 2100 . Accompanying this temperature increase will be increases in some types of extreme weather and a projected sea level rise . The balance of impacts of global warming become significantly negative at larger values of warming .   These findings are recognized by the national science academies of all the major industrialized nations ; the consensus has strengthened over time and is now virtually unanimous . The level of consensus correlates with expertise in climate science .   There have been several efforts to compile lists of dissenting scientists , including a 2008 US senate minority report , the Oregon Petition , and a 2007 list by the Heartland Institute , all three of which have been criticized on a number of grounds .   For the purpose of this list , a `` scientist '' is defined as an individual who has published at least one peer-reviewed research article in the broad field of natural sciences , although not necessarily in a field relevant to climatology . Since the publication of the IPCC Third Assessment Report , each has made a clear statement in his or her own words ( as opposed to the name being found on a petition , etc. ) disagreeing with one or more of the report 's three main conclusions . Their views on climate change are usually described in more detail in their biographical articles . Few of the statements in the references for this list are part of the peer-reviewed scientific literature ; most are from other sources such as interviews , opinion pieces , online essays and presentations .   NB : Only individuals who have their own Wikipedia article may be included in the list .

negative: Global warming controversy The global warming controversy concerns the public debate over whether global warming is occurring , how much has occurred in modern times , what has caused it , what its effects will be , whether any action should be taken to curb it , and if so what that action should be . In the scientific literature , there is a strong consensus that global surface temperatures have increased in recent decades and that the trend is caused by human-induced emissions of greenhouse gases . No scientific body of national or international standing disagrees with this view , though a few organizations with members in extractive industries hold non-committal positions . Disputes over the key scientific facts of global warming are more prevalent in the media than in the scientific literature , where such issues are treated as resolved , and such disputes are more prevalent in the United States than globally .   Political and popular debate concerning the existence and cause of climate change includes the reasons for the increase seen in the instrumental temperature record , whether the warming trend exceeds normal climatic variations , and whether human activities have contributed significantly to it . Scientists have resolved these questions decisively in favour of the view that the current warming trend exists and is ongoing , that human activity is the cause , and that it is without precedent in at least 2000 years . Public disputes that also reflect scientific debate include estimates of how responsive the climate system might be to any given level of greenhouse gases ( climate sensitivity ) , how global climate change will play out at local and regional scales , and what the consequences of global warming will be .   Global warming remains an issue of widespread political debate , often split along party political lines , especially in the United States . Many of the issues that are settled within the scientific community , such as human responsibility for global warming , remain the subject of politically or economically motivated attempts to downplay , dismiss or deny them -- an ideological phenomenon categorised by academics and scientists as climate change denial . The sources of funding for those involved with climate science -- both supporting and opposing mainstream scientific positions -- have been questioned by both sides . There are debates about the best policy responses to the science , their cost-effectiveness and their urgency . Climate scientists , especially in the United States , have reported official and oil-industry pressure to censor or suppress their work and hide scientific data , with directives not to discuss the subject in public communications . Legal cases regarding global warming , its effects , and measures to reduce it have reached American courts . The fossil fuels lobby has been identified as overtly or covertly supporting efforts to undermine or discredit the scientific consensus on global warming .

negative: Temperature record of the past 1000 years For information on the description of the Medieval Warm Period and Little Ice Age in various IPCC reports see MWP and LIA in IPCC reportsThe temperature record of the past 1,000 years is reconstructed using data from climate proxy records in conjunction with the modern instrumental temperature record which only covers the last 150 years at a global scale . Large-scale reconstructions covering part or all of the 1st millennium and 2nd millennium have shown that recent temperatures are exceptional : the Intergovernmental Panel on Climate Change Fourth Assessment Report of 2007 concluded that `` Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely '' the highest in at least the past 1,300 years . '' The curve shown in graphs of these reconstructions is widely known as the hockey stick graph because of the sharp increase in temperatures during the last century . As of 2010 this broad pattern was supported by more than two dozen reconstructions , using various statistical methods and combinations of proxy records , with variations in how flat the pre-20th-century `` shaft '' appears . Sparseness of proxy records results in considerable uncertainty for earlier periods .   Individual proxy records , such as tree ring widths and densities used in dendroclimatology , are calibrated against the instrumental record for the period of overlap . Networks of such records are used to reconstruct past temperatures for regions : tree ring proxies have been used to reconstruct Northern Hemisphere extratropical temperatures ( within the tropics trees do not form rings ) but are confined to land areas and are scarce in the Southern Hemisphere which is largely ocean . Wider coverage is provided by multiproxy reconstructions , incorporating proxies such as lake sediments , ice cores and corals which are found in different regions , and using statistical methods to relate these sparser proxies to the greater numbers of tree ring records . The `` Composite Plus Scaling '' ( CPS ) method is widely used for large-scale multiproxy reconstructions of hemispheric or global average temperatures ; this is complemented by Climate Field Reconstruction ( CFR ) methods which show how climate patterns have developed over large spatial areas , making the reconstruction useful for investigating natural variability and long-term oscillations as well as for comparisons with patterns produced by climate models .   During the 1,900 years before the 20th century , it is likely that the next warmest period was from 950 to 1100 , with peaks at different times in different regions . This has been called the Medieval Warm Period , and some evidence suggests widespread cooler conditions during a period around the 17th century known as the Little Ice Age . In the hockey stick controversy , contrarians have asserted that the Medieval Warm Period was warmer than at present , and have disputed the data and methods of climate reconstructions .

negative: Global warming in Russia Global warming in Russia describes the global warming related issues in Russia . This includes climate politics , contribution to global warming and the influence of global warming on Russia . In 2009 Russia was ready to reduce emissions 20 -- 25 % from its 1990 emission levels by the year 2020 .

negative: Duncan Wingham Duncan John Wingham ( born 12 October 1957 ) is a British physicist who is Professor of Climate Physics at University College London , and was the first Director of the Centre for Polar Observation & Modelling . He is chief executive of the Natural Environment Research Council and Principal Scientist for the CryoSat Satellite Mission .   In the 1990s , Wingham was involved in a four-year satellite study of the Antarctic ice sheet . His conclusion then , and from later research , is that the Antarctic has contributed little to observed rising sea levels in the 20th century . However , he has also stated that `` it is possible that the consequences of global warming on sea level rise have been underestimated ... Other sources of rise must be underestimated . In particular it is possible that the effect of global warming on thermal expansion -LSB- on the oceans -RSB- is larger than we thought '' .   In a 2005 interview Wingham stated '' -LSB- t -RSB- he Antarctic is to some extent insulated from global warming because to its north are zonal flows in the atmosphere and ocean , unimpeded by other landmasses ... I am not denying global warming . ''

negative: Navy Operational Global Atmospheric Prediction System Model Navy Operational Global Atmospheric Prediction System Model ( NOGAPS ) is a global numerical weather prediction computer model run by Fleet Numerical . This mathematical model is run four times a day and produces weather forecasts . Along with the ECMWF 's Integrated Forecast System ( IFS ) , the Canadian Global Environmental Multiscale Model ( GEM ) it is one of several synoptic scale medium-range models in general use .

negative: Climate change and potatoes Global warming is predicted to have significant effects on global potato production . Like many crops , potatoes are likely to be affected by changes in atmospheric carbon dioxide , temperature and precipitation , as well as interactions between these factors . As well as affecting potatoes directly , climate change will also affect the distributions and populations of many potato diseases and pests .  Potato is one of the world 's most important food crops . Potato production must be adapted to climate change to avoid reductions in crop yields .

negative: Save the Planet Save the Planet is a minor political party in Australia .   The environmentalist party aims to avoid global warming by returning average global temperatures to pre-industrial levels as quickly as possible . The party also aims to create a world that is environmentally and socially sustainable without inequality .

negative: James O'Brien (oceanographer) James O'Brien ( born August 10 , 1935 , died September 20 , 2016 ) is the emeritus Robert O. Lawton Professor of Meteorology and Oceanography at Florida State University . He believes sea levels are rising but predicts a more modest 18 in rise instead of 6 ft by 2100 targeted by some other scientists . He stated that `` sea level in Florida is going to continue to rise period . Unless we go back into an Ice age , we will continue to rise at over 8 in in 10 year . That 's without any global warming . ''

negative: Seita Emori Seita Emori ( born 1970 in Kanagawa , Japan ) is a Japanese environmental scientist whose most noted work focuses upon the worldwide effects of Global Warming . He completed his Doctorate at the University of Tokyo in 1997 and thereafter joined the National Institute of Environmental Studies , Japan where he is currently the  Chief of the Climate Risk Assessment Research Section at the Center for Global Environmental Research . Emori is a contributing author to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change ( IPCC ) and a member of the IPCC Steering Committee for the `` Expert Meeting on New Scenarios '' , for which the IPCC received a Noble Prize in 2007 .   Among Emori 's publications are the academic paper `` Sensitivity Map of LAI to Precipitation and Surface Air Temperature Variations in a Global Scale '' ( co-authored with his Japans colleague Hiroshi Kanzawa and Jiahua Zhang and Congbin Fu of the START , Institute of Atmospheric Physics in Beijing , China ) .

negative: Weather Weather is the state of the atmosphere , to the degree that it is hot or cold , wet or dry , calm or stormy , clear or cloudy . Most weather phenomena occur in the lowest level of the atmosphere , the troposphere , just below the stratosphere . Weather refers to day-to-day temperature and precipitation activity , whereas climate is the term for the averaging of atmospheric conditions over longer periods of time . When used without qualification , `` weather '' is generally understood to mean the weather of Earth .   Weather is driven by air pressure , temperature and moisture differences between one place and another . These differences can occur due to the sun 's angle at any particular spot , which varies with latitude . The strong temperature contrast between polar and tropical air gives rise to the largest scale atmospheric circulations : the Hadley Cell , the Ferrel Cell , the Polar Cell , and the jet stream . Weather systems in the mid-latitudes , such as extratropical cyclones , are caused by instabilities of the jet stream flow . Because the Earth 's axis is tilted relative to its orbital plane , sunlight is incident at different angles at different times of the year . On Earth 's surface , temperatures usually range ± 40 ° C ( − 40 ° F to 100 ° F ) annually . Over thousands of years , changes in Earth 's orbit can affect the amount and distribution of solar energy received by the Earth , thus influencing long-term climate and global climate change .   Surface temperature differences in turn cause pressure differences . Higher altitudes are cooler than lower altitudes as most atmospheric heating is due to contact with the Earth 's surface while radiative losses to space are mostly constant . Weather forecasting is the application of science and technology to predict the state of the atmosphere for a future time and a given location . The Earth 's weather system is a chaotic system ; as a result , small changes to one part of the system can grow to have large effects on the system as a whole . Human attempts to control the weather have occurred throughout history , and there is evidence that human activities such as agriculture and industry have modified weather patterns .   Studying how the weather works on other planets has been helpful in understanding how weather works on Earth . A famous landmark in the Solar System , Jupiter 's Great Red Spot , is an anticyclonic storm known to have existed for at least 300 years . However , weather is not limited to planetary bodies . A star 's corona is constantly being lost to space , creating what is essentially a very thin atmosphere throughout the Solar System . The movement of mass ejected from the Sun is known as the solar wind .

negative: Hockey stick graph Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records . These reconstructions have consistently shown a slow long term cooling trend changing into relatively rapid warming in the 20th century , with the instrumental temperature record by 2000 exceeding earlier temperatures .   The term `` hockey stick graph '' was coined by the climatologist Jerry Mahlman , to describe the pattern shown by the ( MBH99 ) reconstruction , envisaging a graph that is relatively flat with a downward trend to 1900 as forming an ice hockey stick 's `` shaft '' followed by a sharp , steady increase corresponding to the `` blade '' portion . The reconstructions have featured in Intergovernmental Panel on Climate Change ( IPCC ) reports as evidence of global warming . Arguments over the reconstructions have been taken up by fossil fuel industry funded lobbying groups attempting to cast doubt on climate science .   Paleoclimatology dates back to the 19th century , and the concept of examining varves in lake beds and tree rings to track local climatic changes was suggested in the 1930s . In the 1960s , Hubert Lamb generalised from historical documents and temperature records of central England to propose a Medieval Warm Period from around 900 to 1300 , followed by Little Ice Age . This was the basis of a `` schematic diagram '' featured in the IPCC First Assessment Report of 1990 beside cautions that the medieval warming might not have been global . The use of indicators to get quantitative estimates of the temperature record of past centuries was developed , and by the late 1990s a number of competing teams of climatologists found indications that recent warming was exceptional . introduced the `` Composite Plus Scaling '' ( CPS ) method used by most later large scale reconstructions . Their study was featured in the IPCC Second Assessment Report of 1995 .   In 1998 Michael E. Mann , Raymond S. Bradley and Malcolm K. Hughes developed new statistical techniques to produce ( MBH98 ) , the first eigenvector-based climate field reconstruction ( CFR ) . This showed global patterns of annual surface temperature , and included a graph of average hemispheric temperatures back to 1400 with shading emphasising that uncertainties ( to two standard error limits ) were much greater in earlier centuries . independently produced a CPS reconstruction extending back for a thousand years , and ( MBH99 ) used the MBH98 methodology to extend their study back to 1000 .   A version of the MBH99 graph was featured prominently in the 2001 IPCC Third Assessment Report ( TAR ) , which also drew on Jones et al. 1998 and three other reconstructions to support the conclusion that , in the Northern Hemisphere , the 1990s was likely to have been the warmest decade and 1998 the warmest year during the past 1,000 years . The graph became a focus of dispute for those opposed to the strengthening scientific consensus that late 20th century warmth was exceptional . In 2003 , as lobbying over the 1997 Kyoto Protocol intensified , a paper claiming greater medieval warmth was quickly dismissed by scientists in the Soon and Baliunas controversy . Later in 2003 , Stephen McIntyre and Ross McKitrick published disputing the data used in MBH98 paper . In 2004 Hans von Storch published criticism of the statistical techniques as tending to underplay variations in earlier parts of the graph , though this was disputed and he later accepted that the effect was very small . In 2005 McIntyre and McKitrick published criticisms of the principal components analysis methodology as used in MBH98 and MBH99 . Their analysis was subsequently disputed by published papers including and which pointed to errors in the McIntyre and McKitrick methodology . Political disputes led to the formation of a panel of scientists convened by the National Research Council , their North Report in 2006 supported Mann 's findings with some qualifications , including agreeing that there were some statistical failings but these had little effect on the result .   More than two dozen reconstructions , using various statistical methods and combinations of proxy records , support the broad consensus shown in the original 1998 hockey-stick graph , with variations in how flat the pre-20th century `` shaft '' appears . The 2007 IPCC Fourth Assessment Report cited 14 reconstructions , 10 of which covered 1,000 years or longer , to support its strengthened conclusion that it was likely that Northern Hemisphere temperatures during the 20th century were the highest in at least the past 1,300 years . Further reconstructions , including Mann et al. 2008 and , have supported these general conclusions .

negative: The 11th Hour (2007 film) The 11th Hour is a 2007 documentary film , created , produced , co-written and narrated by Leonardo DiCaprio , on the state of the natural environment . It was directed by Leila Conners Petersen and Nadia Conners and financed by Adam Lewis and Pierre André Senizergues , and distributed by Warner Independent Pictures .   Its world premiere was at the 2007 60th Annual Cannes Film Festival ( May 16 -- 27 , 2007 ) and it was released on August 17 , 2007 , in the year in which the Fourth Assessment Report of the United Nations global warming panel IPCC was published and about a year after Al Gore 's An Inconvenient Truth , another film documentary about global warming .

negative: Effects of global warming on marine mammals The effect of global warming on marine mammals is a growing concern . Many of the effects of climate change are currently unknown due to its unpredictability , but many are becoming increasingly evident today . Some effects are very direct such as loss of habitat , temperature stress , and exposure to severe weather . Other effects are more indirect such as changes in host pathogen associations , changes in body condition because of predator -- prey interaction , changed in exposure to toxins , and increased human interactions . These are just a few examples of what marine mammals are dealing with as a result of rapid climate change . There are a number of marine mammals that have been affected by climate change including walruses , seals , penguins , and polar bears .

negative: Global horizontal sounding technique The Global horizontal sounding technique ( GHOST ) program was an atmospheric field research project in the late 1960s for investigating the technical ability to gather weather data using thousands of simultaneous long-duration balloons for very long-range global scale numerical weather prediction in preparation for the Global Atmospheric Research Program ( GARP ) .

negative: Bjørn Lomborg Bjørn Lomborg ( -LSB- bjɶɐ̯n ˈlʌmbɒˀw -RSB- ; born 6 January 1965 ) is a Danish author and adjunct professor at the Copenhagen Business School as well as President of the Copenhagen Consensus Center . He is former director of the Danish government 's Environmental Assessment Institute ( EAI ) in Copenhagen . He became internationally known for his best-selling and controversial book , The Skeptical Environmentalist ( 2001 ) , in which he argues that many of the costly measures and actions adopted by scientists and policy makers to meet the challenges of global warming will ultimately have minimal impact on the world 's rising temperature .   In 2002 , Lomborg and the Environmental Assessment Institute founded the Copenhagen Consensus , a project-based conference where prominent economists sought to establish priorities for advancing global welfare using methods based on the theory of welfare economics .   In 2009 , Business Insider cited Lomborg as one of `` The 10 Most-Respected Global Warming Skeptics '' . While Lomborg campaigned against the Kyoto Protocol and other measures to cut carbon emissions in the short-term , he argued for adaptation to short-term temperature rises , and for spending money on research and development for longer-term environmental solutions . His issue is not with the reality of climate change , but rather with the economic and political approaches being taken ( or not taken ) to meet the challenges of that climate change . He is a strong advocate for focusing attention and resources on what he perceives as far more pressing world problems , such as AIDS , malaria and malnutrition . In his critique of the 2012 United Nations Conference on Environment and Development , Lomborg stated : `` Global warming is by no means our main environmental threat . '' In 2011 and 2012 , Lomborg was named a Top 100 Global Thinker by Foreign Policy `` for looking more right than ever on the politics of climate change '' .

negative: Retreat of glaciers since 1850 The retreat of glaciers since 1850 affects the availability of fresh water for irrigation and domestic use , mountain recreation , animals and plants that depend on glacier-melt , and , in the longer term , the level of the oceans . Studied by glaciologists , the temporal coincidence of glacier retreat with the measured increase of atmospheric greenhouse gases is often cited as an evidentiary underpinning of global warming . Mid-latitude mountain ranges such as the Himalayas , Alps , Rocky Mountains , Cascade Range , and the southern Andes , as well as isolated tropical summits such as Mount Kilimanjaro in Africa , are showing some of the largest proportionate glacial losses .   Glacier mass balance is the key determinant of the health of a glacier . If the amount of frozen precipitation in the accumulation zone exceeds the quantity of glacial ice lost due to melting or in the ablation zone a glacier will advance ; if the accumulation is less than the ablation , the glacier will retreat . Glaciers in retreat will have negative mass balances , and if they do not find an equilibrium between accumulation and ablation , will eventually disappear .   The Little Ice Age was a period from about 1550 to 1850 when the world experienced relatively cooler temperatures compared to the present . Subsequently , until about 1940 , glaciers around the world retreated as the climate warmed substantially . Glacial retreat slowed and even reversed temporarily , in many cases , between 1950 and 1980 as global temperatures cooled slightly . Since 1980 , a significant global warming has led to glacier retreat becoming increasingly rapid and ubiquitous , so much so that some glaciers have disappeared altogether , and the existences of many of the remaining glaciers are threatened . In locations such as the Andes of South America and Himalayas in Asia , the demise of glaciers in these regions has the potential to affect water supplies in those areas .   The retreat of mountain glaciers , notably in western North America , Asia , the Alps and tropical and subtropical regions of South America , Africa and Indonesia , provide evidence for the rise in global temperatures since the late 19th century . The acceleration of the rate of retreat since 1995 of key outlet glaciers of the Greenland and West Antarctic ice sheets may foreshadow a rise in sea level , which would affect coastal regions .

negative: Kevin E. Trenberth Kevin Edward Trenberth ( born November 8 , 1944 ) is part of the Climate Analysis Section at the US NCAR National Center for Atmospheric Research . He was a lead author of the 2001 and 2007 IPCC Scientific Assessment of Climate Change ( see IPCC Fourth Assessment Report ) and serves on the Scientific Steering Group for the Climate Variability and Predictability ( CLIVAR ) program . He chaired the WCRP Observation and Assimilation Panel from 2004 to 2010 and chaired the Global Energy and Water Exchanges ( GEWEX ) scientific steering group from 2010-2013 ( member 2007-14 ) . In addition , he served on the Joint Scientific Committee of the World Climate Research Programme , and has made significant contributions to research into El Niño-Southern Oscillation .   Kevin 's work is highly cited and he has an h-index of 100 ( 100 papers have over 100 citations ) .

negative: Rickettsiosis A rickettsiosis is a disease caused by intracellular bacteria . It has been predicted that global warming may lead to greater incidence .

negative: Paleocene–Eocene Thermal Maximum The Paleocene -- Eocene Thermal Maximum ( PETM ) , alternatively ( ETM1 ) , and formerly known as the `` Initial Eocene '' or '' '' was a time period with more than 8 ° C warmer global average temperature than today . This climate event began at the time boundary between the Paleocene and Eocene geological epochs . The exact age and duration of the event is uncertain but it is estimated to have occurred around 55.5 million years ago .   The associated period of massive carbon injection into the atmosphere has been estimated to have lasted no longer than 20,000 years . The entire warm period lasted for about 200,000 years . Global temperatures increased by 5 -- 8 ° C . The carbon dioxide was likely released in two pulses , the first lasting less than 2,000 years . Such a repeated carbon release is in line with current global warming . A main difference is that during the Paleocene -- Eocene Thermal Maximum , the planet was essentially ice-free .   The onset of the Paleocene -- Eocene Thermal Maximum has been linked to an initial 5 ° C temperature rise and to extreme changes in Earth 's carbon cycle . The period is marked by a prominent negative excursion in carbon stable isotope records from around the globe ; more specifically , there was a large decrease in 13C/12C ratio of marine and terrestrial carbonates and organic carbon .   Stratigraphic sections of rock from this period reveal numerous other changes . Fossil records for many organisms show major turnovers . For example , in the marine realm , a mass extinction of benthic foraminifera , a global expansion of subtropical dinoflagellates , and an appearance of excursion , planktic foraminifera and calcareous nanofossils all occurred during the beginning stages of PETM . On land , modern mammal orders ( including primates ) suddenly appear in Europe and in North America . Sediment deposition changed significantly at many outcrops and in many drill cores spanning this time interval .   At least since 1997 , the Paleocene -- Eocene Thermal Maximum has become a focal point of considerable geoscience research because it probably provides the best past analog by which to understand impacts of global climate warming and of massive carbon input to the ocean and atmosphere , including ocean acidification . Although it is now widely accepted that the PETM represents a `` case study '' for global warming and massive carbon input to Earth 's surface , the cause , details and overall significance of the event remain perplexing .

negative: Arctic methane emissions Arctic methane release is the release of methane from seas and soils in permafrost regions of the Arctic . While a long-term natural process , it is exacerbated by global warming . This results in a positive feedback effect , as methane is itself a powerful greenhouse gas .   The Arctic region is one of the many natural sources of the greenhouse gas methane . Global warming accelerates its release , due to both release of methane from existing stores , and from methanogenesis in rotting biomass . Large quantities of methane are stored in the Arctic in natural gas deposits , permafrost , and as undersea clathrates . Permafrost and clathrates degrade on warming , thus large releases of methane from these sources may arise as a result of global warming . Other sources of methane include submarine taliks , river transport , ice complex retreat , submarine permafrost and decaying gas hydrate deposits .   Concentrations in the Arctic atmosphere are higher by 8 -- 10 % than that in the Antarctic atmosphere . During cold glacier epochs , this gradient decreases to practically insignificant levels . Land ecosystems are considered the main sources of this asymmetry , although it has been suggested that `` the role of the Arctic Ocean is significantly underestimated . '' Soil temperature and moisture levels have been found to be significant variables in soil methane fluxes in tundra environments .

negative: Global warming in Tuvalu Global warming is a concern in Tuvalu since the average height of the islands is less than 2 m above sea level , with the highest point of Niulakita being about 4.6 m above sea level . Tuvalu could be one of the first nations to experience the effects of sea level rise . Not only could parts of the island be flooded but the rising saltwater table could also destroy deep rooted food crops such as coconut , pulaka , and taro .

negative: Potential predictability The term potential predictability is used in the context of weather forecasting to describe the extent that the future weather can be predicted in principle , i.e. , it describes the proportion of variance in the weather that arises from systematic factors rather than random noise .

negative: Satellite temperature measurements The temperature of the atmosphere at various altitudes as well as sea and land surface temperatures can be inferred from satellite measurements . These measurements can be used to locate weather fronts , monitor the El Niño-Southern Oscillation , determine the strength of tropical cyclones , study urban heat islands and monitor the global climate . Wildfires , volcanos , and industrial hot spots can also be found via thermal imaging from weather satellites .   Weather satellites do not measure temperature directly . They measure radiances in various wavelength bands . Since 1978 microwave sounding units ( MSUs ) on National Oceanic and Atmospheric Administration polar orbiting satellites have measured the intensity of upwelling microwave radiation from atmospheric oxygen , which is related to the temperature of broad vertical layers of the atmosphere . Measurements of infrared radiation pertaining to sea surface temperature have been collected since 1967 .   Satellite datasets show that over the past four decades the troposphere has warmed and the stratosphere has cooled . Both of these trends are consistent with the influence of increasing atmospheric concentrations of greenhouse gases .

negative: Global warming in Luxembourg Global warming in Luxembourg discuss the global warming issues in Luxembourg .

negative: Heavy Weather (Sterling novel) Heavy Weather is a science fiction novel by Bruce Sterling , first published in 1994 , about a group of storm chasers in a world where global warming has produced incredibly destructive weather .

negative: James Annan James D. Annan is a scientist involved in climate prediction . He was a member of the Global Warming Research Program at Frontier Research Centre for Global Change which is associated with the Earth Simulator in Japan . In 2014 he left Japan , returning to the United Kingdom as a co-founder of Blue Skies Research .

negative: GWPP The initials GWPP could indicate :   the Global Water Policy Project , a fresh-water conservation project headed by Sandra Postel .  the Global Warming Petition Project ( AKA the Oregon Petition ) , a project devoted to discrediting global climate change ( or its previous label global warming ) , under the auspices of the non-profit organization called the Oregon Institute of Science and Medicine .