Resources
The Easter Freeze of April 2007: A Climatological Perspective and Assessment of Impacts and Services (PDF 23.5MB)
Position Statements on Climate Change by Scientific Societies
American Chemical Society (ACS) Position
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). This statement reviews key global climate change impacts and recommends actions required to mitigate or adapt to currently anticipated consequences. More...
American Meteorological Society
The American Meteorological Society (AMS) http://www.ametsoc.org
Council adopted a statement on climate change in February 2003.
The statement reads, in part,
"There is now clear evidence that the mean annual temperature at the Earth's surface, averaged over the entire globe, has been increasing in the past 200 years. There is also clear evidence that the abundance of greenhouse gases in the atmosphere has increased over the same period. In the past decade, significant progress has been made toward a better understanding of the climate system and toward improved projections of long-term climate change... Human activities have become a major source of environmental change. Of great urgency are the climate consequences of the increasing atmospheric abundance of greenhouse gases... Because greenhouse gases continue to increase, we are, in effect, conducting a global climate experiment, neither planned nor controlled, the results of which may present unprecedented challenges to our wisdom and foresight as well as have significant impacts on our natural and societal systems." Read complete statement as follow. More...
Climate Change: An Information Statement of the American Meteorological Society
AGU revises position on climate change
Public release date: January 25, 2008
http://www.eurekalert.org/pub_releases/2008-01/agu-arp012508.php
Contact: Peter Weiss
pweiss@agu.org
202-777-7507
American Geophysical Union
WASHINGTON – A statement released on January 24 by the world’s largest scientific society of Earth and space scientists—the American Geophysical Union, or AGU—updates the organization’s position on climate change: the evidence for it, potential consequences from it, and how to respond to it.
The statement is the first revision since 2003 of the climate-change position of the AGU, which has a membership of 50,000 researchers, teachers, and students in 137 countries. The society adopted the statement at a meeting of AGU’s leadership body, the AGU Council, in San Francisco, California, on 14 December 2007. AGU position statements expire in four years, unless extended by the Council.
Following is the text of the revised statement (also available online at http://www.agu.org/sci_soc/policy/positions/climate_change2008.shtml).
Human Impacts on Climate
The Earth's climate is now clearly out of balance and is warming. Many components of the climate system—including the temperatures of the atmosphere, land and ocean, the extent of sea ice and mountain glaciers, the sea level, the distribution of precipitation, and the length of seasons—are now changing at rates and in patterns that are not natural and are best explained by the increased atmospheric abundances of greenhouse gases and aerosols generated by human activity during the 20th century. Global average surface temperatures increased on average by about 0.6°C over the period 1956–2006. As of 2006, eleven of the previous twelve years were warmer than any others since 1850. The observed rapid retreat of Arctic sea ice is expected to continue and lead to the disappearance of summertime ice within this century. Evidence from most oceans and all continents except Antarctica shows warming attributable to human activities. Recent changes in many physical and biological systems are linked with this regional climate change. A sustained research effort, involving many AGU members and summarized in the 2007 assessments of the Intergovernmental Panel on Climate Change, continues to improve our scientific understanding of the climate.
During recent millennia of relatively stable climate, civilization became established and populations have grown rapidly. In the next 50 years, even the lower limit of impending climate change—an additional global mean warming of 1°C above the last decade—is far beyond the range of climate variability experienced during the past thousand years and poses global problems in planning for and adapting to it. Warming greater than 2°C 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 level of several meters. If this 2°C warming is to be avoided, then our net annual emissions of CO2 must be reduced by more than 50 percent within this century. With such projections, there are many sources of scientific uncertainty, but none are known that could make the impact of climate change inconsequential. Given the uncertainty in climate projections, there can be surprises that may cause more dramatic disruptions than anticipated from the most probable model projections.
With climate change, as with ozone depletion, the human footprint on Earth is apparent. The cause of disruptive climate change, unlike ozone depletion, is tied to energy use and runs through modern society. Solutions will necessarily involve all aspects of society. Mitigation strategies and adaptation responses will call for collaborations across science, technology, industry, and government. Members of the AGU, as part of the scientific community, collectively have special responsibilities: to pursue research needed to understand it; to educate the public on the causes, risks, and hazards; and to communicate clearly and objectively with those who can implement policies to shape future climate.
Adopted by AGU Council, December, 2003
Revised and Reaffirmed, December, 2007
