IPCC underestimates climate risks

Glenn Scherer in the Daily Climate: Across two decades and thousands of pages of reports, the world's most authoritative voice on climate science has consistently understated the rate and intensity of climate change and the danger those impacts represent, say a growing number of studies on the topic.

This conservative bias, say some scientists, could have significant political implications, as reports from the group – the U.N. Intergovernmental Panel on Climate Change – influence policy and planning decisions worldwide, from national governments down to local town councils.

As the latest round of United Nations climate talks in Doha wrap up this week, climate experts warn that the IPCC's failure to adequately project the threats that rising global carbon emissions represent has serious consequences: The IPCC’s overly conservative reading of the science, they say, means governments and the public could be blindsided by the rapid onset of the flooding, extreme storms, drought, and other impacts associated with catastrophic global warming.

"We're underestimating the fact that climate change is rearing its head," said Kevin Trenberth, head of the climate analysis section at the National Center for Atmospheric Research (NCAR) and a lead author of key sections of the 2001 and 2007 IPCC reports. "And we're underestimating the role of humans, and this means we're underestimating what it means for the future and what we should be planning for."...

Photo by Ian Muttoo, Wikimedia Commons via Flickr, under the Creative Commons Attribution-Share Alike 2.0 Generic license

IPCC focuses on natural disasters

The Peninsula (Qatar): Experts recommend avoiding risks in order to minimise the damage caused by climate change, which has stronger impact in underdeveloped regions that are not prepared.

These are some of the conclusions of the report completed by Intergovernmental Panel on Climate Change (IPCC), with authors from 62 countries. The report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation, was the topic of discussion at the UN climate change conference yesterday.

Rajendra K Pachauri, Chairman of IPCC, said that the “increase in sea levels is not our only challenge”, adding that 95 percent of debt for natural disasters affects developing countries.

Maarten van Aalst, from Red Cross/Crescent Climate Centre, said that there are signs of extreme meteorological phenomena, which serve as warning and would avoid many damages. He added that there is need for stronger organisations to do things “smarter and better in the future”.

He talked about certain risk factors that should be taken into consideration, like cooling in public facilities or changes in infrastructure to cope with heat waves in Europe, given that research says that there is a likely increase in heat waves and warm days and nights across Europe.

He also referred to the growing number of hurricanes in US and Caribbean, listing risks like population growth, increasing property rules and higher storm surge with sea level rise. These issues can be addressed with better forecasting, stricter building codes and regional risk pooling...

Sea levels rising more quickly than predicted, warn scientists

Emily Beament in the Independent (UK): Sea levels are rising faster than predicted as a result of climate change, scientists said today. Satellite measurements show sea levels rose 3.2mm a year between 1993 and 2011, 60% above the 2mm estimate in central projections made by the Intergovernmental Panel on Climate Change (IPCC) in its most recent review of climate science.

A study published in the Institute of Physics (IOP) journal Environmental Research Letters said it was "very unlikely" the higher rate of sea level rise is due to natural variability such as temporary ice discharge from ice sheets.

Lead author Stefan Rahmstorf said: "This study shows once again that the IPCC is far from alarmist, but in fact has underestimated the problem of climate change. That applies not just for sea level rise but also to extreme events and the Arctic sea loss."

The researchers also warn that the rate of annual sea level rise may increase as global temperatures go up, a suggestion backed up by past sea level data and which leads to larger projections of future sea level rise than the IPCC predicts.

And they said the concern that the IPCC's estimates for future sea level rise are low is supported by the fact ice sheets in Greenland and Antarctica are increasingly losing mass, while the panel's projections assume that Antarctica will gain enough ice to compensate for losses from Greenland....

Worsening drought conditions due to global warming overestimated

Red Orbit: Reports claiming that the climate change has caused global drought conditions to intensify over the past several decades are flawed and based on faulty calculations, according to a new study published Thursday in the journal Nature.

According to Anna Salleh of ABC News Australia the researchers report in their study that the 2007 4th Assessment Report (AR4) by the UN Intergovernmental Panel on Climate Change (IPCC) “overestimated” reports of an increase of drought conditions throughout the world. That report had claimed that droughts had increased in intensity and duration, and had been observed in more and more locations, especially in the tropics and subtropics, Salleh explained.

The IPCC report was compiled using information from the Palmer Drought Severity Index (PDSI), which lead author Dr Michael Roderick of the Australian Research Council (ARC) Centre of Excellence for Climate System Science and colleagues said is flawed.

“Many climate change researchers use the Palmer Drought Severity Index (PDSI) and calculate evaporative demand as a sole function of temperature,” Dr. Roderick said in a statement. “The use of the PDSI has led to a bias in results that indicated an increase in the area of global drought where none has actually occurred.”

“It is curious that the long term use of the PDSI by climate impact researchers has persisted, when it has been recognized repeatedly as not being a realistic indicator of historical drought conditions,” he added. “Even the section on droughts in the IPCC AR4 report was substantially revised by the more recent IPCC report on extremes because of its over reliance on the PDSI and the potential for overestimating the increases in global and regional drought.”...

A strip of vegetation along the aryk (a channelled creek that flows from the mountains (in the background)) in the desert outside of Tamchy, Kyrgyzstan. Shot by Vmenkov, Wikimedia Commons,  under the Creative Commons Attribution-Share Alike 3.0 Unported license