Q: Why is APS revising its climate change statement?
A: The American Physical Society formally reviews its statements every five years. The APS Panel on Public Affairs (POPA) formed a subcommittee in fall 2013 to review its 2007 Climate Change Statement and 2010 Climate Change Commentary. After reviewing the statement, commentary and recent scientific reports, POPA developed a single, concise statement on Earth's Changing Climate.

Q: Who wrote the statement?
A: The entire APS Panel on Public Affairs (POPA) membership was engaged in drafting the statement. The panel's membership as well as the Charge to POPA and resource documents can be found on the APS Climate Change Statement review website.

Q: What was the process to revise the statement?
A: A detailed description of the process is included in APS News and posted on the APS Climate Change Statement review website. Briefly, the APS Panel on Public Affairs (POPA) adhered to the process outlined in the APS Board & Council Joint Oversight Policies & Procedures, starting with a standard review of the 2007 APS Climate Change Statement and 2010 Climate Change Commentary. Then, a POPA subcommittee convened a workshop to inform itself on aspects of the Intergovernmental Panel on Climate Change (IPCC) consensus view of the physical basis of climate science. That was followed by the drafting of a single, concise statement that was reviewed by POPA and the APS Council. The APS Board unanimously voted to send it to the membership for comment on Feb. 21, 2015.

Q: How does this draft statement compare to the 2007 statement and 2010 commentary?
A: In this draft statement on Earth's Changing Climate, APS "reiterates" its 2007 statement in stating that: the climate is changing, humans are contributing to climate change, and rising concentrations of greenhouse gases pose the risk of significant disruption around the globe. While there remain scientific challenges to our ability to observe, interpret and project climate change, APS continues to support actions - as it did in the 2007 statement - that reduce greenhouse gases and increase the resilience of society to climate change. A primary change is that the draft is succinct and does not require an associated commentary.

Q: What happens to the 2007 statement?
A: If the current draft is ultimately approved by the APS Council, it becomes the current position of APS, and the 2007 statement is moved to the archive on the APS Statements webpage.

Q: What will APS do with the statement?
A: If the statement is approved, then the APS Council and Board will make a decision on whether to pursue any policy or outreach activities related to climate change. Those activities would be carried out by the APS Panel on Public Affairs (POPA) and the APS Physics Policy Committee (PPC).

Q: What is the status of this statement on Earth's Changing Climate?
A: The APS Statement on Earth's Changing Climate is a draft. The development of an APS statement is a deliberative process. During the last year, consistent with APS Board & Council Joint Oversight Policies & Procedures, the APS Panel on Public Affairs (POPA) developed the draft, the Council provided commentary on the draft, and the APS Board voted unanimously to forward the statement to the APS membership. All APS members now have an opportunity to review the statement and provide input during a 30-day comment period. The comments will be reviewed by POPA and the statement may be modified accordingly. The statement will then be presented to the APS Board and APS Council for discussion. If approved by the Council, the statement will become the official position of APS.

Q: Why is APS qualified to comment on the science of climate change?
A: A number of issues associated with climate change are fundamental physics topics, including the connection between greenhouse gas increases and warming, radiative transfer, spectroscopy, thermodynamics, and energy balance. In addition, climate change is an area of interest for many APS members, including the more than 500 APS members who participate in the APS Topical Group on the Physics of Climate.