December 19th, 2006 by Hafiz Noor Shams
Whenever a debate on climate change occurs, more often than not, the Intergovernmental Panel on Climate Change, the IPCC for short, will be cited. The IPCC is regarded by most, according to Wikipedia, as the authority in the science of climate change. Up to date, three Assessment Reports that summarize what we know of climate change have been published. The latest edition was issued in 2001. Come February 2007, the IPCC will release its Fourth Assessment Report.
The third report affirms the relationship between human activities and current climate change we’re experiencing. Quoting a paragraph in page 10 of the Summary for Policymakers of the Third Assessment Report:
In the light of new evidence and taking into account the remaining uncertainties, most of the observed warming over the last 50 years is likely to have been due to the increase in greenhouse gas concentrations.
It also projects an increase of average surface temperature between 1.4º and 5.8º C from 1990 to 2100. Sea level is expected to rise between 0.1 and 0.9 meter during the same period.
While the new report will only be release in February, The Telegraph offers the public a glimpse of what to expect from the report:
In a final draft of its fourth assessment report, to be published in February, the panel reports that the level of carbon dioxide in the atmosphere has accelerated in the past five years. It also predicts that temperatures will rise by up to 4.5 C during the next 100 years, bringing more frequent heat waves and storms.
The panel, however, has lowered predictions of how much sea levels will rise in comparison with its last report in 2001.
Based on the article at The Telegraph, the IPCC sets to restrict the average temperature rise between 1.5º and 4.5º C and decrease the ceiling for the sea level estimated rise from 0.9 meter to 0.4 meter.
Because the latest report tightens the expectation range, in the article:
Climate change sceptics are expected to seize on the revised figures as evidence that action to combat global warming is less urgent.
Before that happens, the point is that:
Scientists insist that the lower estimates for sea levels and the human impact on global warming are simply a refinement due to better data on how climate works rather than a reduction in the risk posed by global warming.
Also, it is expected that the IPCC will make a connection between global warming and stronger storms. The relationship was probably popularized after Katrina hit New Orleans. RealClimate has an article on the relationship between sea temperature and hurricane strength.
Talking about that relationship, some might be tempted to make a connection between climate change and the recent bout of typhoons that had hit eastern part of Southeast Asia. A connection might be made but I’d rather wait for an expert to offer an opinion, especially when El Niño is in the equation. For your information, El Niño transfers warm water from west to east Pacific. Keeping the relationship between warmer water and stronger storm, El Niño introduces weaker storms. Maybe, this is a good question to ask the people at RealClimate.
Regardless, one thing is certain: the 2007 report will maintain the connection between human activities and climate change.