The review of the IPCC’s Regional Chapters in the Working Group II portion of the AR4 was conducted by the Netherlands Environmental Assessment Agency (Plan Bureau voor de Leefomgeving - PBL) at the request of the Dutch Environment Minister. The objective of the review was to investigate if there were errors in these 8 chapters of the 44-chapter AR4. Authors of the IPCC report provided information and inputs as demanded by PBL, but played no role in the preparation of this review.

“The review is explicit in its finding that the key conclusions of the IPCC 4th Assessment Report are accurate, correct and supported entirely by the leading science in the field,” said Martin Parry, Co-Chair of AR4 Working Group II.

The reviewers looked at 32 statements on regional impacts of climate change. Their summary is that all 32 are “well founded and none were found to contain any significant errors”. [1]

The review also states: “The Working Group II contribution to the Fourth Assessment Report shows ample observational evidence of regional climate-change impacts, which have been projected to pose substantial risks to most parts of the world, under increasing temperatures.” [2]

The review serves to reinforce the conclusions on regional impacts of climate change in the 2007 Report: many impacts have been confirmed, and continued climate change will pose serious challenges to human wellbeing and sustainable development.

The IPCC will pay close attention to the PBL’s recommendations for strengthening future reports and will consider these findings in the context of the full set of inputs it receives, especially the findings of the ongoing review by the InterAcademy Council, which was jointly requested by the Secretary-General of the United Nations and the IPCC.

Dr. Rajendra Pachauri, Chairman of the IPCC said: “We consider the PBL review a useful acknowledgement of the IPCC’s central role as an independent source of scientific knowledge on climate change, helping inform decision makers around the world with its objective assessments.”

[1] Netherlands Environmental Assessment Agency (PBL). Assessing an IPCC assessment:
An analysis of statements on projected regional impacts in the 2007 report. The
Hague/Bilthoven, 2010. p.9
[2] Ibid. p.9