The statement, signed by 31 U.S. scientific societies and coalitions, reaffirms the scientific consensus that climate change is occurring and human activities are the primary driver.
On June 28, a prominent group of U.S.-based scientific societies and coalitions issued a brief but strongly worded statement to Congress that reaffirms the scientific consensus on climate change. The five-paragraph statement, which is a reissue of an earlier statement that a smaller subset of the societies delivered to Congress in 2009, states human activities are the primary driver of climate change. It also asserts there is strong evidence that ongoing climate change is having broad negative impacts on society, including on the economy, natural resources, and human health.
The American Meteorological Society, an AIP Member Society, is a signatory, and signed the original 2009 statement. Other signatories include the American Association for the Advancement of Science, American Chemical Society, American Geophysical Union, American Public Health Association, American Statistical Association, Geological Society of America, and University Corporation for Atmospheric Research.
The American Physical Society (APS), another AIP Member Society, chose not to sign the statement, but APS staff says its decision is not a rejection of the statement. Rather, the society prefers to speak with its own words. Because the wording of the APS Statement on Earth’s Changing Climate, adopted last November, is sufficiently different from the joint society statement to Congress, APS chose to abstain.
The authoritative Fifth Assessment Report of the U.N. Intergovernmental Panel on Climate Change, finalized in 2014, found that warming of the atmosphere and ocean system is unequivocal and that it is “extremely likely” that human influence has been the dominant cause of observed warming since 1950. The National Climate Assessment, published in May 2014 by the U.S. Global Change Research Program, and America’s Climate Choices report, published in 2011 by the National Academy of Sciences, echo those findings.
Joint society statement on climate change science
The statement that the 31 scientific societies and coalitions delivered to Congress reads as follows:
We, as leaders of major scientific organizations, write to remind you of the consensus scientific view of climate change.
Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research concludes that the greenhouse gases emitted by human activities are the primary driver. This conclusion is based on multiple independent lines of evidence and the vast body of peer-reviewed science.
There is strong evidence that ongoing climate change is having broad negative impacts on society, including the global economy, natural resources, and human health. For the United States, climate change impacts include greater threats of extreme weather events, sea level rise, and increased risk of regional water scarcity, heat waves, wildfires, and the disturbance of biological systems. The severity of climate change impacts is increasing and is expected to increase substantially in the coming decades.
To reduce the risk of the most severe impacts of climate change, greenhouse gas emissions must be substantially reduced. In addition, adaptation is necessary to address unavoidable consequences for human health and safety, food security, water availability, and national security, among others.
We, in the scientific community, are prepared to work with you on the scientific issues important to your deliberations as you seek to address the challenges of our changing climate.
APS statement on ‘Earth’s Changing Climate’
The APS statement on climate change, approved by the APS Council in November 2015, reads as follows:
On Climate Change:
Earth's changing climate is a critical issue and poses the risk of significant environmental, social and economic disruptions around the globe. While natural sources of climate variability are significant, multiple lines of evidence indicate that human influences have had an increasingly dominant effect on global climate warming observed since the mid-twentieth century. Although the magnitudes of future effects are uncertain, human influences on the climate are growing. The potential consequences of climate change are great and the actions taken over the next few decades will determine human influences on the climate for centuries.
On Climate Science:
As summarized in the 2013 report of the Intergovernmental Panel on Climate Change (IPCC), there continues to be significant progress in climate science. In particular, the connection between rising concentrations of atmospheric greenhouse gases and the increased warming of the global climate system is more compelling than ever. Nevertheless, as recognized by Working Group 1 of the IPCC, scientific challenges remain in our abilities to observe, interpret, and project climate changes. To better inform societal choices, the APS urges sustained research in climate science.
On Climate Action:
The APS reiterates its 2007 call to support actions that will reduce the emissions, and ultimately the concentration, of greenhouse gases as well as increase the resilience of society to a changing climate, and to support research on technologies that could reduce the climate impact of human activities. Because physics and its techniques are fundamental elements of climate science, the APS further urges physicists to collaborate with colleagues across disciplines in climate research and to contribute to the public dialogue.