IPCC Hones Its Language on Climate Change

The Athabasca Glacier, a part of the Columbia Icefields in Alberta, Canada, is receding on an average of 16 feet per year.
The Athabasca Glacier, a part of the Columbia Icefields in the Rocky Mountains of Alberta, Canada, has receded 0.93 miles (1.5 km) over the last 125 years.

Yesterday the Intergovernmental Panel on Climate Change (IPCC) released its latest Synthesis Report (SYR5) – a summary of the IPCC’s Fifth Assessment Report (AR5) on the state of knowledge on climate change. The big news with the SYR5’s release is the change in language used within the report – words like “unequivocable” and “clear” now replace the earlier usage of “probable” and “likely” when describing global warming and the role that human activity has played in the temperature increase. Text from the SYR5 underscores this major language shift:

 “Warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia. The atmosphere and ocean have warmed, the amounts of snow and ice have diminished, and sea level has risen.”

…and

“Human influence on the climate system is clear, and recent anthropogenic emissions of greenhouse gases are the highest in history.”

The SYR5 summarizes IPCC’s three other major reports on various facets of climate change that were released in 2013-2014. These reports are all available from the IPCC website:

  • Climate Change 2013 – The Physical Science Basis;
  • Climate Change 2014 – Impacts, Adaptations, and Vulnerability; and
  • Climate Change 2014 – Mitigation of Climate Change.

The Carbon Brief 11/2/2014 blog gives a listing and good, brief descriptions of what else is noteworthy in the SYR5. Here’s a quick recap on their list:

  • Global warming continues unabated
  • Human influence on warming is clear
  • Ocean acidification, sea level rise, glacial ice decline
  • IPCC’s new carbon budget
  • Consequences of inaction – climate change impacts
  • Low carbon transition – costs and savngs