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IPCC Fifth Assessment Report: more certainty, not much news

By Steve Sherwood and Lisa Alexander

What new does the IPCC's fifth report have to say about our climate problem?

The full text of this article can be purchased from Informit.

The part of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report dealing with the physical basis of climate change has now been released.

The report – released in Stockholm – is more than 2,000 pages long, has assessed nearly 10,000 peer-reviewed scientific studies, most of them published since the previous assessment in 2007, and (as with previous assessments) went through three rounds of detailed review by 1,089 expert and government reviewers worldwide to ensure balance and accuracy.

So what new does it have to say about our climate problem?

The short answer, at least with respect to the big picture: not much. Despite a recent slowdown of surface ocean warming, the world is still warming and humans are still behind most if not all of the change. Much larger changes loom in the future if business-as-usual continues. If emissions come down, those changes won’t be as bad.

Little progress has been made in narrowing the range of future global warming rates or quantifying the role of aerosols (airborne particles such as soot) in offsetting the warming to date. Confidence in regional predictions of...

The full text of this article can be purchased from Informit.