科學界中存在一個明確的關於氣候變化的科學共識（英語：Scientific consensus on climate change）：地球氣候正在變暖中，導致的主因是由人類活動所造成。這項共識由各種研究學者的意見和科學組織發表的立場聲明予以支持，其中許多明確贊同聯合國政府間氣候變化專門委員會（IPCC）綜合報告中的陳述。
氣候變化為[人類]社會帶來的好處與成本將因地點和規模的不同而有很大差異。[45]有些對溫帶和極地的影響將為正面，而在其他地方的影響則為負面。[45]整體而言，隨著暖化幅度增強或是加快，淨效應更有可能是強烈的負面影響。[45] Overall, net effects are more likely to be strongly negative with larger or more rapid warming.[45]
非洲科學院網絡（英語：Network of African Science Academies）為參與籌備第33屆八大工業國高峰會議，於2007年提交一份名為"《永續發展、能源效率和氣候變化聲明（statement on sustainability, energy efficiency, and climate change）》"的聯合聲明：
美國國家科學院透過其氣候變化科學委員會於2001年出版一份名為《氣候變化科學：一些關鍵問題的分析（Climate Change Science: An Analysis of Some Key Questions）》的報告。[69]報告明確認可IPCC對近期氣候變化歸因的觀點，認為其代表科學界的看法：[69]
美國農學會（英語：American Society of Agronomy） (ASA)、美國作物科學學會 (Crop Science Society of America，CSSA) 和美國土壤科學學會 (Soil Science Society of America，SSSA) 於2011年5月就農業相關的氣候變化發表聯合立場聲明：[90]
Dennis Bray與Hans von Storch（英語：Hans von Storch）兩位教授於2008年8月對來自34個國家，共2,058名氣候科學家進行一項調查。[145]為每為受訪者提供一個具有特別辨識的網絡鏈接，以避免重複回答，一共收到373份回覆，整體回覆率為18.2%。迄2010年2月，基於這項調查的氣候變化共識論文尚未發佈，但基於這項調查的結果已有一篇涵蓋另一個主題的論文發表。[146]
詹姆斯·勞倫斯·鮑威爾（英語：James L. Powell）在2017年發表的報告中稱，對1991年至2015年期間發表的同行評審文獻（包括前述中的幾項）進行的五次調查，於總計54,195篇文章中，平均共識率為99.94%。[155]他於2019年11月對2019年前7個月發表的11,600多篇同行評審文章進行調查，顯示共識達到100%。[2]
Changes in global temperature are usually expressed in terms of temperature anomalies. "In climate change studies, temperature anomalies are more important than absolute temperature. A temperature anomaly is the difference from an average, or baseline, temperature. The baseline temperature is typically computed by averaging 30 or more years of temperature data."[11]
Cook, John; Oreskes, Naomi; Doran, Peter T.; Anderegg, William R. L.; et al. Consensus on consensus: a synthesis of consensus estimates on human-caused global warming. Environmental Research Letters. 2016, 11 (4): 048002. Bibcode:2016ERL....11d8002C. doi:10.1088/1748-9326/11/4/048002.
Lynas, Mark; Houlton, Benjamin Z.; Perry, Simon. Greater than 99% consensus on human caused climate change in the peer-reviewed scientific literature. Environmental Research Letters. 2021-10-19, 16 (11): 114005. Bibcode:2021ERL....16k4005L. S2CID 239032360. doi:10.1088/1748-9326/ac2966.
Myers, Krista F.; Doran, Peter T.; Cook, John; Kotcher, John E.; Myers, Teresa A. Consensus revisited: quantifying scientific agreement on climate change and climate expertise among Earth scientists 10 years later. Environmental Research Letters. 2021-10-20, 16 (10): 104030. Bibcode:2021ERL....16j4030M. S2CID 239047650. doi:10.1088/1748-9326/ac2774.
"Total radiative forcing is positive and has led to an uptake of energy by the climate system. The largest contribution to total radiative forcing is caused by the increase in the atmospheric concentration of CO2 since 1750." and "From 1750 to 2011, CO2 emissions from fossil fuel combustion and cement production have released 375 [345 to 405] GtC to the atmosphere, while deforestation and other land-use change are estimated to have released 180 [100 to 260] GtC." In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change （頁面存檔備份，存於網際網路檔案館） [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
Joint Science Academies' Statement(PDF). 2005 [2014-04-20]. （原始內容(PDF)存檔於2013-09-09）. It is likely that most of the warming in recent decades can be attributed to human activities (IPCC 2001). This warming has already led to changes in the Earth's climate.
Julie Brigham-Grette. Petroleum Geologists' Award to Novelist Crichton Is Inappropriate. Eos. September 2006, 87 (36): 364. Bibcode:2006EOSTr..87..364B. doi:10.1029/2006EO360008. The AAPG stands alone among scientific societies in its denial of human-induced effects on global warming.
Did You Know?. www.ncdc.noaa.gov. National Centers for Environmental Information, National Oceanic and Atmospheric Administration. [2019-10-01]. （原始內容存檔於2021-12-28）.
Cook, John; Oreskes, Naomi; Doran, Peter T.; Anderegg, William R. L.; Verheggen, Bart; Maibach, Ed W.; Carlton, J. Stuart; Lewandowsky, Stephan; Skuce, Andrew G.; Green, Sarah A.; Nuccitelli, Dana; Jacobs, Peter; Richardson, Mark; Winkler, Bärbel; Painting, Rob; Rice, Ken. Consensus on consensus: a synthesis of consensus estimates on human-caused global warming. Environmental Research Letters. 2016, 11 (4): 048002. Bibcode:2016ERL....11d8002C. ISSN 1748-9326. doi:10.1088/1748-9326/11/4/048002（英語）.
Scientific consensus: Earth's climate is warming. Climate Change: Vital Signs of the Planet (National Aeronautics and Space Administration (NASA)). [2018-08-18]. （原始內容存檔於2019-06-17）. Multiple studies published in peer-reviewed scientific journals1 show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities. In addition, most of the leading scientific organizations worldwide have issued public statements endorsing this position.
IPCC, Summary for Policymakers(PDF), Detection and Attribution of Climate Change, [2023-11-13], （原始內容存檔(PDF)於2017-01-11）, "It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century" (page 17) and "In this Summary for Policymakers, the following terms have been used to indicate the assessed likelihood of an outcome or a result: ... extremely likely: 95–100%" (page 2)., in IPCC AR5 WG1 2013.
[Notes-SciPanel] America's Climate Choices: Panel on Advancing the Science of Climate Change; National Research Council. Advancing the Science of Climate Change. Washington, D.C.: The National Academies Press. 2010. ISBN 978-0-309-14588-6. （原始內容存檔於2014-05-29）. (p1) there is a strong, credible body of evidence, based on multiple lines of research, documenting that climate is changing and that these changes are in large part caused by human activities. While much remains to be learned, the core phenomenon, scientific questions, and hypotheses have been examined thoroughly and have stood firm in the face of serious scientific debate and careful evaluation of alternative explanations. * * * (p. 21–22) Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities.
IPCC, 2014: Climate Change 2014: Synthesis Report （頁面存檔備份，存於網際網路檔案館）. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R. K. Pachauri and L. A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp.
Julie Brigham-Grette; et al. Petroleum Geologists' Award to Novelist Crichton Is Inappropriate. Eos. September 2006, 87 (36): 364. Bibcode:2006EOSTr..87..364B. doi:10.1029/2006EO360008. The AAPG stands alone among scientific societies in its denial of human-induced effects on global warming.
Rosenthal, Elisabeth; Revkin, Andrew C. Science Panel Calls Global Warming 'Unequivocal'. The New York Times. 3 February 2007 [2010-08-28]. （原始內容存檔於2023-04-14）. the leading international network of climate scientists has concluded for the first time that global warming is 'unequivocal' and that human activity is the main driver, 'very likely' causing most of the rise in temperatures since 1950
Stevens, William K. On the Climate Change Beat, Doubt Gives Way to Certainty. The New York Times. 2007-02-06 [28 August 2010]. （原始內容存檔於2023-06-28）. The Intergovernmental Panel on Climate Change said the likelihood was 90 percent to 99 percent that emissions of heat-trapping greenhouse gases like carbon dioxide, spewed from tailpipes and smokestacks, were the dominant cause of the observed warming of the last 50 years. In the panel's parlance, this level of certainty is labeled "very likely." Only rarely does scientific odds-making provide a more definite answer than that, at least in this branch of science, and it describes the endpoint, so far, of a progression.
Royal Flemish Academy of Belgium for Sciences the Arts; Royal Society of Canada; German Academy of Natural Scientists Leopoldina; Indian National Science Academy; Accademia Nazionale dei Lincei (Italy); Academy Council of the Royal Society of New Zealand; Royal Swedish Academy of Sciences; Royal Society (UK). Editorial: The Science of Climate Change. Science. 18 May 2001, 292 (5520): 1261. PMID 11360966. S2CID 129309907. doi:10.1126/science.292.5520.1261.
Stanowisko Zgromadzenia Ogólnego PAN z dnia 13 grudnia 2007 r(PDF). Polish Academy of Sciences. [2009-06-16]. （原始內容存檔(PDF)於2016-05-03） （波蘭語）. Note: As of 16 June 2009, PAS has not issued this statement in English, all citations have been translated from Polish.
FASTS Statement on Climate Change(PDF), 2008 [2015-07-29], （原始內容存檔(PDF)於2013-05-11） "Global climate change is real and measurable. Since the start of the 20th century, the global mean surface temperature of the Earth has increased by more than 0.7°C and the rate of warming has been largest in the last 30 years. Key vulnerabilities arising from climate change include water resources, food supply, health, coastal settlements, biodiversity and some key ecosystems such as coral reefs and alpine regions. As the atmospheric concentration of greenhouse gases increases, impacts become more severe and widespread. To reduce the global net economic, environmental and social losses in the face of these impacts, the policy objective must remain squarely focused on returning greenhouse gas concentrations to near pre-industrial levels through the reduction of emissions. The spatial and temporal fingerprint of warming can be traced to increasing greenhouse gas concentrations in the atmosphere, which are a direct result of burning fossil fuels, broad-scale deforestation and other human activity."
Joint statement by the Network of African Science Academies (NASAC) to the G8 on sustainability, energy efficiency and climate change. 2007 [2015-05-22]. （原始內容存檔於2017-06-09）. A consensus, based on current evidence, now exists within the global scientific community that human activities are the main source of climate change and that the burning of fossil fuels is largely responsible for driving this change ... Although we recognize that this nexus poses daunting challenges for the developed world, we firmly believe that these challenges are even more daunting for the most impoverished, science-poor regions of the developing world, especially in Africa.
European Science Foundation Position Paper Impacts of Climate Change on the European Marine and Coastal Environment — Ecosystems Approach: 7–10, 2007 [2015-07-29], （原始內容存檔於2009-07-30） "There is now convincing evidence that since the industrial revolution, human activities, resulting in increasing concentrations of greenhouse gases have become a major agent of climate change. These greenhouse gases affect the global climate by retaining heat in the troposphere, thus raising the average temperature of the planet and altering global atmospheric circulation and precipitation patterns. While on-going national and international actions to curtail and reduce greenhouse gas emissions are essential, the levels of greenhouse gases currently in the atmosphere, and their impact, are likely to persist for several decades. On-going and increased efforts to mitigate climate change through reduction in greenhouse gases are therefore crucial."
American Chemical Society Global Climate Change, [2015-07-29], （原始內容存檔於2012-02-24） "Careful and comprehensive scientific assessments have clearly demonstrated that the Earth's climate system is changing rapidly in response to growing atmospheric burdens of greenhouse gases and absorbing aerosol particles (IPCC, 2007). There is very little room for doubt that observed climate trends are due to human activities. The threats are serious and action is urgently needed to mitigate the risks of climate change. The reality of global warming, its current serious and potentially disastrous impacts on Earth system properties, and the key role emissions from human activities play in driving these phenomena have been recognized by earlier versions of this ACS policy statement (ACS, 2004), by other major scientific societies, including the American Geophysical Union (AGU, 2003), the American Meteorological Society (AMS, 2007) and the American Association for the Advancement of Science (AAAS, 2007), and by the U. S. National Academies and ten other leading national academies of science (NA, 2005)."
American Physical Society Climate Change Policy Statement, November 2007 [2015-07-29], （原始內容存檔於2023-09-04） "Emissions of greenhouse gases from human activities are changing the atmosphere in ways that affect the Earth's climate. Greenhouse gases include carbon dioxide as well as methane, nitrous oxide and other gases. They are emitted from fossil fuel combustion and a range of industrial and agricultural processes. The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth's physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now. Because the complexity of the climate makes accurate prediction difficult, the APS urges an enhanced effort to understand the effects of human activity on the Earth's climate, and to provide the technological options for meeting the climate challenge in the near and longer terms. The APS also urges governments, universities, national laboratories and its membership to support policies and actions that will reduce the emission of greenhouse gases.
AIP science policy document.(PDF), 2005 [2015-07-29], （原始內容存檔(PDF)於2016-03-03） "Policy: The AIP supports a reduction of the green house gas emissions that are leading to increased global temperatures, and encourages research that works towards this goal. Reason: Research in Australia and overseas shows that an increase in global temperature will adversely affect the Earth's climate patterns. The melting of the polar ice caps, combined with thermal expansion, will lead to rises in sea levels that may impact adversely on our coastal cities. The impact of these changes on biodiversity will fundamentally change the ecology of Earth."
EPS Position Paper Energy for the future: The Nuclear Option(PDF), 2007 [2023-11-13], （原始內容存檔(PDF)於2016-04-17） "The emission of anthropogenic greenhouse gases, among which carbon dioxide is the main contributor, has amplified the natural greenhouse effect and led to global warming. The main contribution stems from burning fossil fuels. A further increase will have decisive effects on life on earth. An energy cycle with the lowest possible CO2 emission is called for wherever possible to combat climate change."
Ledley, Tamara S.; Sundquist, Eric T.; Schwartz, Stephen E.; Hall, Dorothy K.; Fellows, Jack D.; Killeen, Timothy L. Climate Change and Greenhouse Gases. EOS. 1999-09-28, 80 (39): 453–454, 457–458. Bibcode:1999EOSTr..80Q.453L. doi:10.1029/99EO00325. There is no known geologic precedent for large increases of atmospheric CO2 without simultaneous changes in other components of the carbon cycle and climate system. ... Changes in the climate system that are confidently predicted in response to increases in greenhouse gases include increases in mean surface air temperature, increases in global mean rates of precipitation and evaporation, rising sea level, and changes in the biosphere.
AAWV Position Statement on Climate Change, Wildlife Diseases, and Wildlife Health "There is widespread scientific agreement that the world's climate is changing and that the weight of evidence demonstrates that anthropogenic factors have and will continue to contribute significantly to global warming and climate change. It is anticipated that continuing changes to the climate will have serious negative impacts on public, animal and ecosystem health due to extreme weather events, changing disease transmission dynamics, emerging and re-emerging diseases, and alterations to habitat and ecological systems that are essential to wildlife conservation. Furthermore, there is increasing recognition of the inter-relationships of human, domestic animal, wildlife, and ecosystem health as illustrated by the fact the majority of recent emerging diseases have a wildlife origin."
AIBS Position Statements, [2015-07-29], （原始內容存檔於2020-10-26） "Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver."
Global Environmental Change — Microbial Contributions, Microbial Solutions(PDF), American Society For Microbiology, May 2006 [2015-07-29], （原始內容存檔(PDF)於2016-04-15） They recommended "reducing net anthropogenic CO2 emissions to the atmosphere" and "minimizing anthropogenic disturbances of" atmospheric gases. Carbon dioxide concentrations were relatively stable for the past 10,000 years but then began to increase rapidly about 150 years ago...as a result of fossil fuel consumption and land use change. Of course, changes in atmospheric composition are but one component of global change, which also includes disturbances in the physical and chemical conditions of the oceans and land surface. Although global change has been a natural process throughout Earth's history, humans are responsible for substantially accelerating present-day changes. These changes may adversely affect human health and the biosphere on which we depend. Outbreaks of a number of diseases, including Lyme disease, hantavirus infections, dengue fever, bubonic plague, and cholera, have been linked to climate change."
Australian Coral Reef Society official letter(PDF), 2006, （原始內容(PDF)存檔於22 March 2006） Official communique regarding the Great Barrier Reef and the "world-wide decline in coral reefs through processes such as overfishing, runoff of nutrients from the land, coral bleaching, global climate change, ocean acidification, pollution", etc.: There is almost total consensus among experts that the earth's climate is changing as a result of the build-up of greenhouse gases. The IPCC (involving over 3,000 of the world's experts) has come out with clear conclusions as to the reality of this phenomenon. One does not have to look further than the collective academy of scientists worldwide to see the string (of) statements on this worrying change to the earth's atmosphere. There is broad scientific consensus that coral reefs are heavily affected by the activities of man and there are significant global influences that can make reefs more vulnerable such as global warming. ... It is highly likely that coral bleaching has been exacerbated by global warming."
Institute of Biology policy page 'Climate Change', [2015-07-29], （原始內容存檔於2007-10-10） "there is scientific agreement that the rapid global warming that has occurred in recent years is mostly anthropogenic, ie due to human activity." As a consequence of global warming, they warn that a "rise in sea levels due to melting of ice caps is expected to occur. Rises in temperature will have complex and frequently localised effects on weather, but an overall increase in extreme weather conditions and changes in precipitation patterns are probable, resulting in flooding and drought. The spread of tropical diseases is also expected." Subsequently, the Institute of Biology advocates policies to reduce "greenhouse gas emissions, as we feel that the consequences of climate change are likely to be severe."
SAF Forest Management and Climate Change (PDF), 2008 [2009-01-29], （原始內容(PDF)存檔於2012-02-22） "Forests are shaped by climate. ... Changes in temperature and precipitation regimes therefore have the potential to dramatically affect forests nationwide. There is growing evidence that our climate is changing. The changes in temperature have been associated with increasing concentrations of atmospheric carbon dioxide (CO2) and other GHGs in the atmosphere."
Wildlife Society Global Climate Change and Wildlife(PDF), （原始內容(PDF)存檔於27 November 2008） "Scientists throughout the world have concluded that climate research conducted in the past two decades definitively shows that rapid worldwide climate change occurred in the 20th century, and will likely continue to occur for decades to come. Although climates have varied dramatically since the Earth was formed, few scientists question the role of humans in exacerbating recent climate change through the emission of greenhouse gases. The critical issue is no longer "if" climate change is occurring, but rather how to address its effects on wildlife and wildlife habitats." The statement goes on to assert that "evidence is accumulating that wildlife and wildlife habitats have been and will continue to be significantly affected by ongoing large-scale rapid climate change." The statement concludes with a call for "reduction in anthropogenic (human-caused) sources of carbon dioxide and other greenhouse gas emissions contributing to global climate change and the conservation of CO2- consuming photosynthesizers (i.e., plants)."
AAP Global Climate Change and Children's Health, 2007 [2009-02-13], （原始內容存檔於22 July 2009） "There is broad scientific consensus that Earth's climate is warming rapidly and at an accelerating rate. Human activities, primarily the burning of fossil fuels, are very likely (>90% probability) to be the main cause of this warming. Climate-sensitive changes in ecosystems are already being observed, and fundamental, potentially irreversible, ecological changes may occur in the coming decades. Conservative environmental estimates of the impact of climate changes that are already in process indicate that they will result in numerous health effects to children. Anticipated direct health consequences of climate change include injury and death from extreme weather events and natural disasters, increases in climate-sensitive infectious diseases, increases in air pollution–related illness, and more heat-related, potentially fatal, illness. Within all of these categories, children have increased vulnerability compared with other groups."
ACPM Policy Statement Abrupt Climate Change and Public Health Implications, 2006 [21 November 2008], （原始內容存檔於7 November 2007） "The American College of Preventive Medicine (ACPM) accept the position that global warming and climate change is occurring, that there is potential for abrupt climate change, and that human practices that increase greenhouse gases exacerbate the problem, and that the public health consequences may be severe."
American Medical Association Policy Statement, 2008 [2015-07-29], （原始內容存檔於2023-10-17） "Support the findings of the latest Intergovernmental Panel on Climate Change report, which states that the Earth is undergoing adverse global climate change and that these changes will negatively affect public health. Support educating the medical community on the potential adverse public health effects of global climate change, including topics such as population displacement, flooding, infectious and vector-borne diseases, and healthy water supplies."
AMA Climate Change and Human Health — 2004, 2004[永久失效連結] They recommend policies "to mitigate the possible consequential health effects of climate change through improved energy efficiency, clean energy production and other emission reduction steps."
AMA Climate Change and Human Health — 2004. Revised 2008., 2008, （原始內容存檔於16 February 2009） "The world's climate – our life-support system – is being altered in ways that are likely to pose significant direct and indirect challenges to health. While 'climate change' can be due to natural forces or human activity, there is now substantial evidence to indicate that human activity – and specifically increased greenhouse gas (GHGs) emissions – is a key factor in the pace and extent of global temperature increases. Health impacts of climate change include the direct impacts of extreme events such as storms, floods, heatwaves and fires and the indirect effects of longer-term changes, such as drought, changes to the food and water supply, resource conflicts and population shifts. Increases in average temperatures mean that alterations in the geographic range and seasonality of certain infections and diseases (including vector-borne diseases such as malaria, dengue fever, Ross River virus and food-borne infections such as Salmonellosis) may be among the first detectable impacts of climate change on human health. Human health is ultimately dependent on the health of the planet and its ecosystem. The AMA believes that measures which mitigate climate change will also benefit public health. Reducing GHGs should therefore be seen as a public health priority."
World Federation of Public Health Associations resolution "Global Climate Change"(PDF), 2001, （原始內容(PDF)存檔於17 December 2008） "Noting the conclusions of the United Nations' Intergovernmental Panel on Climate Change (IPCC) and other climatologists that anthropogenic greenhouse gases, which contribute to global climate change, have substantially increased in atmospheric concentration beyond natural processes and have increased by 28 percent since the industrial revolution….Realizing that subsequent health effects from such perturbations in the climate system would likely include an increase in: heat-related mortality and morbidity; vector-borne infectious diseases,… water-borne diseases…(and) malnutrition from threatened agriculture….the World Federation of Public Health Associations…recommends precautionary primary preventive measures to avert climate change, including reduction of greenhouse gas emissions and preservation of greenhouse gas sinks through appropriate energy and land use policies, in view of the scale of potential health impacts".
Statement supporting AGU statement on human-induced climate change, American Astronomical Society, 2004, （原始內容存檔於2007-05-07） "In endorsing the "Human Impacts on Climate" statement [issued by the American Geophysical Union], the AAS recognizes the collective expertise of the AGU in scientific subfields central to assessing and understanding global change, and acknowledges the strength of agreement among our AGU colleagues that the global climate is changing and human activities are contributing to that change."
ASA Statement on Climate Change, 30 November 2007 [2015-07-29], （原始內容存檔於2016-07-22） "The ASA endorses the IPCC conclusions.... Over the course of four assessment reports, a small number of statisticians have served as authors or reviewers. Although this involvement is encouraging, it does not represent the full range of statistical expertise available. ASA recommends that more statisticians should become part of the IPCC process. Such participation would be mutually beneficial to the assessment of climate change and its impacts and also to the statistical community."
Policy Statement, Climate Change and Energy, February 2007 [2015-07-29], （原始內容存檔於2007-11-03） "Engineers Australia believes that Australia must act swiftly and proactively in line with global expectations to address climate change as an economic, social and environmental risk ... We believe that addressing the costs of atmospheric emissions will lead to increasing our competitive advantage by minimising risks and creating new economic opportunities. Engineers Australia believes the Australian Government should ratify the Kyoto Protocol."
IAGLR Fact Sheet The Great Lakes at a Crossroads: Preparing for a Changing Climate(PDF), February 2009 [2015-07-29], （原始內容存檔(PDF)於2023-03-20） "While the Earth's climate has changed many times during the planet's history because of natural factors, including volcanic eruptions and changes in the Earth's orbit, never before have we observed the present rapid rise in temperature and carbon dioxide (CO2). Human activities resulting from the industrial revolution have changed the chemical composition of the atmosphere. ... Deforestation is now the second largest contributor to global warming, after the burning of fossil fuels. These human activities have significantly increased the concentration of "greenhouse gases" in the atmosphere. As the Earth's climate warms, we are seeing many changes: stronger, more destructive hurricanes; heavier rainfall; more disastrous flooding; more areas of the world experiencing severe drought; and more heat waves."
IPENZ Informatory Note, Climate Change and the greenhouse effect(PDF), October 2001 [2015-07-29], （原始內容存檔(PDF)於2012-03-06） "Human activities have increased the concentration of these atmospheric greenhouse gases, and although the changes are relatively small, the equilibrium maintained by the atmosphere is delicate, and so the effect of these changes is significant. The world's most important greenhouse gas is carbon dioxide, a by-product of the burning of fossil fuels. Since the time of the Industrial Revolution about 200 years ago, the concentration of carbon dioxide in the atmosphere has increased from about 280 parts per million to 370 parts per million, an increase of around 30%. On the basis of available data, climate scientists are now projecting an average global temperature rise over this century of 2.0 to 4.5°C. This compared with 0.6°C over the previous century – about a 500% increase ... This could lead to changing, and for all emissions scenarios more unpredictable, weather patterns around the world, less frost days, more extreme events (droughts and storm or flood disasters), and warmer sea temperatures and melting glaciers causing sea levels to rise. ... Professional engineers commonly deal with risk, and frequently have to make judgments based on incomplete data. The available evidence suggests very strongly that human activities have already begun to make significant changes to the earth's climate, and that the long-term risk of delaying action is greater than the cost of avoiding/minimising the risk."
Cook, John; Oreskes, Naomi; Doran, Peter T.; Anderegg, William R. L.; Verheggen, Bart; Maibach, Ed W.; Carlton, J. Stuart; Lewandowsky, Stephan; Skuce, Andrew G.; Green, Sarah A.; Nuccitelli, Dana. Consensus on consensus: a synthesis of consensus estimates on human-caused global warming. Environmental Research Letters. April 2016, 11 (4): 048002. Bibcode:2016ERL....11d8002C. ISSN 1748-9326. doi:10.1088/1748-9326/11/4/048002（英語）.
Powell, James Lawrence. The Consensus on Anthropogenic Global Warming Matters. Bulletin of Science, Technology & Society. 2017-05-24, 36 (3): 157–163. S2CID 148618842. doi:10.1177/0270467617707079（英語）.
Lynas, Mark; Houlton, Benjamin Z.; Perry, Simon. Greater than 99% consensus on human caused climate change in the peer-reviewed scientific literature. Environmental Research Letters. 2021-10-19, 16 (11): 114005. Bibcode:2021ERL....16k4005L. S2CID 239032360. doi:10.1088/1748-9326/ac2966.
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