- This topic is empty.
27 January 2008 at 4:31 pm #3489Martin WParticipant
Time, I think, to start a thread with some info on
Positions re climate change of some major groups of scientists
Prompted by new statement on the issue by the American Geophysicist's Union. From American Scientist article:Quote:The scientists of the American Geophysical Union (AGU) warn that greenhouse gas (GHG) emissions must be slashed in half to keep temperatures from rising 3.6 degrees Fahrenheit (2 degrees Celsius)—or else. "Warming greater than 2 degrees Celsius above 19th-century levels is projected to be disruptive, reducing global agricultural productivity, causing widespread loss of biodiversity and—if sustained over centuries—melting much of the Greenland ice sheet with ensuing rise in sea levels of several meters," the AGU declares in its first statement in four years on "Human Impacts on Climate."
The statement, released today, is the latest—and strongest—statement from the Washington, D.C.–based scientific organization on human-induced climate change. "The record of the Earth's climate since the invention of the thermometer is much better understood now," says physicist Tim Killeen, AGU president and director of the National Center for Atmospheric Research (NCAR) in Boulder, Colo.
"This detailed understanding of the climate of the 20th century gives confidence in the ability to project into the future. It is now agreed that we can't explain the detailed temperature record of the 20th century without bringing to bear human effects and GHG emissions. That, in a way, is the smoking gun, the fingerprint."
Geophysicists Urge Steep Cuts in Greenhouse Gas Emissions The American Geophysical Union says massive reductions in greenhouse gases will be needed—and scientists should speak up about it24 September 2008 at 10:46 am #4546
UK Met Office website has page headed "Global warming goes on", inc:Quote:
Anyone who thinks global warming has stopped has their head in the sand. The evidence is clear – the long-term trend in global temperatures is rising, and humans are largely responsible for this rise. Global warming does not mean that each year will be warmer than the last, natural phenomena will mean that some years will be much warmer and others cooler. You only need to look at 1998 to see a record-breaking warm year caused by a very strong El Niño. In the last couple of years, the underlying warming is partially masked caused by a strong La Niña. Despite this, 11 of the last 13 years are the warmest ever recorded.
Average global temperatures are now some 0.75 °C warmer than they were 100 years ago. Since the mid-1970s, the increase in temperature has averaged more than 0.15 °C per decade. This rate of change is very unusual in the context of past changes and much more rapid than the warming at the end of the last ice age. Sea-surface temperatures have warmed slightly less than the global average whilst temperatures over land have warmed at a faster rate of almost 0.3 °C per decade.
Over the last ten years, global temperatures have warmed more slowly than the long-term trend. But this does not mean that global warming has slowed down or even stopped. It is entirely consistent with our understanding of natural fluctuations of the climate within a trend of continued long-term warming.
Global warming goes on – from the page, you can download pdf re global warming27 December 2008 at 1:52 pm #4569
American Association for the Advancement of Science unequivocal here:Quote:AAAS Board of Directors Statement on Climate Change: "The scientific evidence is clear," the AAAS Board says in a new statement. "Global climate change caused by human activities…is a growing threat to society." The statement was approved on 9 December 2006 and released on 18 February at the AAAS Annual Meeting in San Francisco.27 December 2008 at 1:59 pm #4570Quote:The national science academies of the G8 nations and Brazil, China, India, Mexico and South Africa have signed a statement on climate change adaptation and the transition to a low carbon society. Adaptation is necessary if the worst impacts of climate change, now and in the future, are to be alleviated. Mitigation and adaptation can complement each other and if pursued together can significantly reduce the risks of climate change impacts.
The statement calls on world leaders, particularly those meeting at the G8 Summit in Toyako, Hokkaido, in July 2008 to:
- To make maximum efforts to commit to halving global greenhouse gas emissions by 2050.
- Agree, by 2009, a timetable, funding, and a coordinated plan for the construction of a significant number of Carbon Capture and Storage demonstration plants.
- Prepare for the challenges and risks posed by climate change by improving predictive and adaptive capacities at global, national and local level and supporting the developing world in carrying out vulnerability analyses and addressing their findings.
- Take appropriate economic and policy measures to accelerate transition to a low carbon society and to encourage and effect changes in individual and national behaviour.
- Promote science and technology co-operation, innovation and leapfrogging, e.g., by transfer of some basic critical low-carbon and adaptation technologies.
- Urge governments to support research on greenhouse gas reduction technologies and climate change impacts.
2008 Joint science academies’ statement: Climate change adaptation and the transition of a low carbon society27 December 2008 at 2:06 pm #4571
Intergovernmental Panel on Climate Change, in 2007 assessment report publishedQuote:Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level.
Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the
observed increase in anthropogenic GHG concentrations. It is likely that there has been significant anthropogenic warming over the past 50 years averaged over each continent (except Antarctica).20 January 2009 at 7:31 am #4582
Not an organisation here, but survey of scientists showing great majority believe human-induced climate change is real; with belief strongest in those who know the issue best, climatologists.Quote:Survey: Scientists Agree Human-Induced Global Warming is Real
While the harsh winter pounding many areas of North America and Europe seemingly contradicts that global warming continues unabated, a new survey finds consensus among scientists about the reality of climate change and its likely cause.
A group of 3,146 earth scientists surveyed around the world overwhelmingly agree that in the past 200-plus years, mean global temperatures have been rising, and that human activity is a significant contributing factor in changing mean global temperatures.
Peter Doran, University of Illinois at Chicago associate professor of earth and environmental sciences, along with former graduate student Maggie Kendall Zimmerman, conducted the survey late last year.
The findings appear today in Eos, the newspaper of earth and space sciences published by American Geophysical Union.
In trying to overcome criticism of earlier attempts to gauge the view of earth scientists on global warming and the human impact factor, Doran and Kendall Zimmerman sought the opinion of the most complete list of earth scientists they could find, contacting more than 10,200 experts around the world listed in the 2007 edition of the American Geological Institute’s Directory of Geoscience Departments.
Experts in academia and government research centers were e-mailed invitations to participate in the on-line poll conducted by the website questionpro.com. Only those invited could participate and computer IP addresses of participants were recorded and used to prevent repeat voting. Questions used were reviewed by a polling expert who checked for bias in phrasing, such as suggesting an answer by the way a question was worded. The nine-question survey was short, taking just a few minutes to complete.
Two questions were key: have mean global temperatures risen compared to pre-1800s levels, and has human activity been a significant factor in changing mean global temperatures.
About 90 percent of the scientists agreed with the first question and 82 percent the second.
In analyzing responses by sub-groups, Doran found that climatologists who are active in research showed the strongest consensus on the causes of global warming, with 97 percent agreeing humans play a role. Petroleum geologists and meteorologists were among the biggest doubters, with only 47 and 64 percent respectively believing in human involvement. Doran compared their responses to a recent poll showing only 58 percent of the public thinks human activity contributes to global warming.
"The petroleum geologist response is not too surprising, but the meteorologists’ is very interesting," he said. "Most members of the public think meteorologists know climate, but most of them actually study very short-term phenomenon."
He was not surprised, however, by the near-unanimous agreement by climatologists.
"They’re the ones who study and publish on climate science. So I guess the take-home message is, the more you know about the field of climate science, the more you’re likely to believe in global warming and humankind’s contribution to it." [Bold and Italics mine – Martin]
Doran and Kendall Zimmerman conclude that "the debate on the authenticity of global warming and the role played by human activity is largely nonexistent among those who understand the nuances and scientific basis of long-term climate processes." The challenge now, they write, is how to effectively communicate this to policy makers and to a public that continues to mistakenly perceive debate among scientists.20 May 2009 at 12:30 pm #4615Anonymous
at the end of the year the summit will take place
this is where we need to head27 June 2009 at 2:47 pm #4625
"Warming greater than 2 degrees Celsius above 19th-century levels is projected to be disruptive, reducing global agricultural productivity, causing widespread loss of biodiversity and—if sustained over centuries—melting much of the Greenland ice sheet with ensuing rise in sea levels of several meters". if this is so then you we are about to find some hard times.24 November 2009 at 7:29 am #4626
The Guardian has just published full text of a statement from the Met Office, the Natural Environment Research Council and the Royal Society on the state of the science of climate change ahead of the Copenhagen climate conference. Includes:Quote:As three of the UK’s leading scientific organisations involving most of the UK scientists working on climate change, we cannot emphasise enough the body of scientific evidence that underpins the call for action now, and we reinforce our commitment to ensuring that world leaders continue to have access to the best possible science.
We expect some of the most significant impacts of climate change to occur when natural variability is exacerbated by long-term global warming, so that even small changes in global temperatures can produce damaging local and regional effects. Year on year the evidence is growing that damaging climate and weather events – potentially intensified by global warming – are already happening and beginning to affect society and ecosystems.
The 2007 IPCC assessment, the most comprehensive and respected analysis of climate change to date, states clearly that without substantial global reductions of greenhouse gas emissions we can likely expect a world of increasing droughts, floods and species loss, of rising seas and displaced human populations. However even since the 2007 IPCC assessment the evidence for dangerous, long-term and potentially irreversible climate change has strengthened. The scientific evidence which underpins calls for action at Copenhagen is very strong. Without co-ordinated international action on greenhouse gas emissions, the impacts on climate and civilisation could be severe.
Full text: Climate science statement27 April 2010 at 5:51 am #4696
Position statement on climate change, from Geological Society of America (just revised):Quote:Decades of scientific research have shown that climate can change from both natural and anthropogenic causes. The Geological Society of America (GSA) concurs with assessments by the National Academies of Science (2005), the National Research Council (2006), and the Intergovernmental Panel on Climate Change (IPCC, 2007) that global climate has warmed and that human activities (mainly greenhouse‐gas emissions) account for most of the warming since the middle 1900s. If current trends continue, the projected increase in global temperature by the end of the twentyfirst century will result in large impacts on humans and other species. Addressing the challenges posed by climate change will require a combination of adaptation to the changes that are likely to occur and global reductions of CO2 emissions from anthropogenic sources.
Notes:Quote:Scientific advances in the first decade of the 21st century have greatly reduced previous uncertainties about the amplitude and causes of recent global warming.26 May 2010 at 7:04 am #4714
From press release from US National Academies:Quote:As part of its most comprehensive study of climate change to date, the National Research Council today issued three reports emphasizing why the U.S. should act now to reduce greenhouse gas emissions and develop a national strategy to adapt to the inevitable impacts of climate change. The reports by the Research Council, the operating arm of the National Academy of Sciences and National Academy of Engineering, are part of a congressionally requested suite of five studies known as America's Climate Choices.
"These reports show that the state of climate change science is strong," said Ralph J. Cicerone, president of the National Academy of Sciences. "But the nation also needs the scientific community to expand upon its understanding of why climate change is happening, and focus also on when and where the most severe impacts will occur and what we can do to respond." 'Poses Significant Risks'
The compelling case that climate change is occurring and is caused in large part by human activities is based on a strong, credible body of evidence, says Advancing the Science of Climate Change, one of the new reports. While noting that there is always more to learn and that the scientific process is never "closed," the report emphasizes that multiple lines of evidence support scientific understanding of climate change. The core phenomenon, scientific questions, and hypotheses have been examined thoroughly and have stood firm in the face of serious debate and careful evaluation of alternative explanations.
"Climate change is occurring, is caused largely by human activities, and poses significant risks for — and in many cases is already affecting — a broad range of human and natural systems," the report concludes.
STRONG EVIDENCE ON CLIMATE CHANGE UNDERSCORES NEED
FOR ACTIONS TO REDUCE EMISSIONS AND BEGIN ADAPTING TO IMPACTS17 July 2010 at 2:45 am #4726
From the National Academies – members of which have dubbed new era we are entering "The Anthropocene":Quote:NEAR-TERM EMISSIONS CHOICES COULD LOCK IN CLIMATE CHANGES FOR CENTURIES TO MILLENNIA; REPORT ESTIMATES IMPACTS FROM VARIOUS LEVELS OF WARMING
WASHINGTON— Choices made now about carbon dioxide emissions reductions will affect climate change impacts experienced not just over the next few decades but also in coming centuries and millennia, says a new report from the National Research Council.Because CO2 in the atmosphere is long lived, it can effectively lock the Earth and future generations into a range of impacts, some of which could become very severe.
Policy choices about emissions can be informed by recent advances in climate research that quantify the relationships between atmospheric CO2 and warming levels, and between warming levels and future impacts.Drawing upon this research, the report estimates changes in precipitation, streamflow, wildfires, crop yields, and sea level rise that can be expected with different degrees of warming.It also estimates the average temperature increases that would be likely if CO2 were stabilized in the atmosphere at various target levels.However, the report does not recommend any particular stabilization target, noting that choosing among different targets is a policy choice rather than strictly a scientific one because of questions of values regarding how much risk or damage to people or to nature might be considered too much.
Increased Confidence About Future Impacts
Although some important future effects of climate change are difficult to quantify, there is now increased confidence in how global warming of various levels would relate to several key impacts, says the report.It lists some of these impacts per degree Celsius (or per 1.8 degrees Fahrenheit) of global warming, for example (these apply for 1 C to 4 C of warming):
- 5 percent to 10 percent less total rain in southwest North America, the Mediterranean, and southern Africa per degree Celsius of warming.
- 5 percent to 10 percent less streamflow in some river basins, including the Arkansas and Rio Grande, per degree Celsius of warming.
- 5 percent to 15 percent lower yields of some crops, including U.S. and African corn and Indian wheat, per degree Celsius of warming.
While total rain is expected to decrease in some areas, more of the rain that does occur is expected to occur in heavy falls in most land areas (3 percent to 10 percent more heavy rain per degree Celsius).In addition, warming of 1C to 2 C (1.8 F to 3.6 F) could be expected to lead to a twofold to fourfold increase per degree in the area burned by wildfire in parts of western North America, the report says.Warming of 3 C (5.4 F) would put many millions more people at risk of coastal flooding and lead to the loss of about 250,000 square km of wetlands and drylands.And warming of 4 C (7.2 F) would lead to far warmer summers; about nine out of 10 summers would be warmer than the warmest ever experienced during the last decades of the 20th century over nearly all land areas.
Stabilizing Atmospheric CO2 Requires Deep Emissions Cuts
Currently the concentration of CO2 in the atmosphere is about 390 parts per million volume (ppmv), the highest level in at least 800,000 years.Depending on emissions rates, that level could double or nearly triple by the end of the century, greatly amplifying future human impacts on climate, the report says.
Because the amount of human-caused CO2 emissions already far exceeds the amount that can be removed through natural carbon "sinks" such as oceans, keeping emissions rates the same will not stabilize the concentration of CO2 in the atmosphere.Even if emissions held steady, the CO2 concentration in the atmosphere would increase, much like the water level in a bathtub when water is coming in faster than it is draining.Emissions reductions larger than about 80 percent, relative to whatever peak global emissions rate may be reached, would be required to approximately stabilize carbon dioxide concentrations for a century or so at any chosen target level.
Further, stabilizing atmospheric concentrations does not mean that temperatures will stabilize immediately.Warming that occurs in response to a given increase in the CO2 concentration is only about half the total warming that will ultimately occur.For example, if the CO2 concentration stabilizes at 550 ppmv, the Earth would warm about 1.6 C on the way to that level; but even after the CO2 level stabilizes, the warming would continue to grow in the following decades and centuries, reaching a best-estimate global "equilibrium" warming of about 3 C (5.4 F).Waiting to observe impacts before choosing a stabilization target would therefore imply a lock-in to about twice as much eventual crop loss, rainfall changes, and other impacts that increase with warming.
The report offers likely ranges and best estimates of the equilibrium warming that can be expected from various levels of CO2 in the atmosphere:
Table 1: Relationship of Atmospheric Concentrations of Carbon Dioxide to Temperature
The report was sponsored by the Energy Foundation and the U.S. Environmental Protection Agency.The National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council make up the National Academies.They are independent, nonprofit institutions that provide science, technology, and health policy advice under an 1863 congressional charter.Committee members, who serve pro bono as volunteers, are chosen by the Academies for each study based on their expertise and experience and must satisfy the Academies' conflict-of-interest standards.The resulting consensus reports undergo external peer review before completion.For more information, visit http://national-academies.org/studycommitteprocess.pdf.A committee roster follows.
Copies of Climate Stabilization Targets: Emissions, Concentrations, and Impacts Over Decades to Millennia are available from the National Academies Press; tel. 202-334-3313 or 1-800-624-6242 or on the Internet at http://www.nap.edu.Reporters may obtain a copy from the Office of News and Public Information (contacts listed above).
[ This news release and report are available at http://national-academies.org ]
NATIONAL RESEARCH COUNCIL13 December 2010 at 1:53 am #4753
The Geological Society has prepared a position statement on climate change, focusing specifically on the geological evidence. Includes:Quote:The Greenhouse Effect arises because certain gases (the so-called greenhouse gases) in the atmosphere absorb the long wavelength infrared radiation emitted by the Earth’s surface and re-radiate it, so warming the atmosphere. This natural effect keeps our atmosphere some 30ºC warmer than it would be without those gases. Increasing the concentration of such gases will increase the effect (i.e. warm the atmosphere more).
Over at least the last 200 million years the fossil and sedimentary record shows that the Earth has undergone many fluctuations in climate, from warmer than the present climate to much colder, on many different timescales. Several warming events can be associated with increases in the ‘greenhouse gas’ CO2. There is evidence for sudden major injections of carbon to the atmosphere occurring at 55, 120 and 183 million years ago, perhaps from the sudden breakdown of methane hydrates beneath the seabed. At those times the associated warming would have increased the evaporation of water vapour from the ocean, making CO2 the trigger rather than the sole agent for change. During the Ice Age of the past two and a half million years or so, periodic warming of the Earth through changes in its position in relation to the sun also heated the oceans, releasing both CO2 and water vapour, which amplified the ongoing warming into warm interglacial periods. That process was magnified by the melting of sea ice and land ice, darkening the Earth’s surface and reducing the reflection of the Sun’s energy back into space.
While these past climatic changes can be related to geological events, it is not possible to relate the Earth’s warming since 1970 to anything recognisable as having a geological cause
In the coming centuries, continued emissions of carbon from burning oil, gas and coal at close to or higher than today’s levels, and from related human activities, could increase the total to close to the amounts added during the 55 million year warming event – some 1500 to 2000 billion tonnes. Further contributions from ‘natural’ sources (wetlands, tundra, methane hydrates, etc.) may come as the Earth warms. The geological evidence from the 55 million year event and from earlier warming episodes suggests that such an addition is likely to raise average global temperatures by at least 5-6ºC, and possibly more, and that recovery of the Earth’s climate in the absence of any mitigation measures could take 100,000 years or more. Numerical models of the climate system support such an interpretation. In the light of the evidence presented here it is reasonable to conclude that emitting further large amounts of CO2 into the atmosphere over time is likely to be unwise, uncomfortable though that fact may be.6 September 2011 at 6:24 am #4813
From Drovers CattleNetwork:Quote:Three agricultural societies recently published a position statement on climate change. The American Society of Agronomy (1), the Crop Science Society of America (2) and the Soil Science Society of America (3) released a statement in May of 2011. The information below is taken from the statement which can be found in its entirety this link.
The position statement begins, “A comprehensive body of scientific evidence indicates beyond reasonable doubt that global climate change is now occurring and that its manifestations threaten the stability of societies as well as natural and managed ecosystems. Increases in ambient temperatures and changes in related processes are directly linked to rising anthropogenic (4) greenhouse gas (GHG) concentrations in the atmosphere.”
It goes on to state that “The potential related impacts of climate change on the ability of agricultural systems, which include soil and water resources, to provide food, feed,fiber, and fuel, and maintenance of ecosystem services … as well as the integrity of the environment, are major concerns.”
Moreover,the report states that crop production will face increasing challenges linked to climate change.
Other Position Statements on Climate Change (5)
A large number of other scientific organizations have issued position statements on climate change. The listing may not be inclusive of all scientific organization position statements.
Statements by concurring organizations
- Academies of Science — joint statement by 32 national science academies
- InterAcademy Council
- European Academy of Sciences and Arts
- International Council of Academies of Engineering and Technological Sciences
- Network of African Science Academies
- Royal Society of New Zealand
- Royal Society of the United Kingdom
- Polish Academy of Sciences
- National Research Council (US)
- American Association for the Advancement of Science
- American Chemical Society
- American Institute of Physics
- American Physical Society
- Australian Institute of Physics
- European Physical Society
- European Science Foundation
- Federation of Australian Scientific and Technological Societies
- American Geophysical Union
- European Federation of Geologists
- European Geosciences Union
- Geological Society of America
- Geological Society of Australia
- Geological Society of London
- International Union of Geodesy and Geophysics
- National Association of Geoscience Teachers
- American Meteorological Society
- Australian Meteorological and Oceanographic Society
- Canadian Foundation for Climate and Atmospheric Sciences
- Canadian Meteorological and Oceanographic Society
- Royal Meteorological Society (UK)
- World Meteorological Organization
- American Quaternary Association
- International Union for Quaternary Research
- American Association of Wildlife Veterinarians
- American Institute of Biological Sciences
- American Society for Microbiology
- Australian Coral Reef Society
- Institute of Biology (UK)
- Society of American Foresters
- The Wildlife Society (international)
- American Academy of Pediatrics
- American College of Preventive Medicine
- American Medical Association
- American Public Health Association
- Australian Medical Association
- World Federation of Public Health Associations
- World Health Organization
- American Astronomical Society
- American Statistical Association
- Engineers Australia (The Institution of Engineers Australia)
- International Association for Great Lakes Research
- Institute of Professional Engineers New Zealand
- American Association of Petroleum Geologists
- American Association of State Climatologists
- American Geological Institute
- American Institute of Professional Geologists
- Canadian Federation of Earth Sciences
Statements by dissenting organizations
No dissenting statements on climate change by scientific organizations were listed. However, a number of individual scientists are on record as dissenters. Regardless, a number of surveys have revealed that a substantial majority of scientists believe that global warming is occurring and that human factors are a major contributor.28 August 2012 at 4:49 am #4871
New statement on global warming from American Meteorological Society concludes:Quote:There is unequivocal evidence that Earth’s lower atmosphere, ocean, and land surface are warming; sea level is rising; and snow cover, mountain glaciers, and Arctic sea ice are shrinking. The dominant cause of the warming since the 1950s is human activities. This scientific finding is based on a large and persuasive body of research. The observed warming will be irreversible for many years into the future, and even larger temperature increases will occur as greenhouse gases continue to accumulate in the atmosphere. Avoiding this future warming will require a large and rapid reduction in global greenhouse gas emissions. The ongoing warming will increase risks and stresses to human societies, economies, ecosystems, and wildlife through the 21st century and beyond, making it imperative that society respond to a changing climate. To inform decisions on adaptation and mitigation, it is critical that we improve our understanding of the global climate system and our ability to project future climate through continued and improved monitoring and research. This is especially true for smaller (seasonal and regional) scales and weather and climate extremes, and for important hydroclimatic variables such as precipitation and water availability.
Technological, economic, and policy choices in the near future will determine the extent of future impacts of climate change. Science-based decisions are seldom made in a context of absolute certainty. National and international policy discussions should include consideration of the best ways to both adapt to and mitigate climate change. Mitigation will reduce the amount of future climate change and the risk of impacts that are potentially large and dangerous. At the same time, some continued climate change is inevitable, and policy responses should include adaptation to climate change. Prudence dictates extreme care in accounting for our relationship with the only planet known to be capable of sustaining human life.
An Information Statement of the American Meteorological Society
(Adopted by AMS Council 20 August 2012)13 March 2016 at 11:22 am #4936
http://climate.nasa.gov/scientific-consensus/6 July 2016 at 5:58 pm #4943
from Scientific American:
Thirty-one of the largest U.S. science societies—collectively representing millions of scientists—sent a letter to Congress this week urging lawmakers to recognize anthropogenic climate change and take decisive action to combat it and its effects. “The letter continues the decades-long efforts of the scientific community to persuade Congress to act on the climate crisis,” says Sarah Green, a chemistry professor at Michigan Technological University who studies climate change and who is affiliated with of several of the societies that signed the letter.
http://www.scientificamerican.com/article/top-u-s-science-organizations-hammer-congress-on-climate-change-mdash-again/18 January 2017 at 2:44 pm #4946
Statements on Climate Change from Major Scientific Academies, Societies, and Associations (January 2017 update):
http://scienceblogs.com/significantfigures/index.php/2017/01/07/statements-on-climate-change-from-major-scientific-academies-societies-and-associations-january-2017-update/10 March 2017 at 2:47 am #4948
Experts rip into new US EPA head Scott Pruitt for claiming rising carbon dioxide levels may not be primary cause of climate change
- You must be logged in to reply to this topic.