IPCC 2013 report drafts leaked

[Robert Maxwell]

Link

The Intergovernmental Panel on Climate Change is not releasing their next report until late next year, but some draft versions are already circulating. In summary, the predictions aren't changing that much, though they are becoming more precise.

Greater sea level rises are anticipated, but fewer strong storms and droughts.

Highlights from the article:

The IPCC's predictions concerning precipitation, on the other hand, may be more conservative than in the previous assessment. Computer models certainly show a clear trend: In places where it already rains a great deal, it will rain even more; and where it is currently dry, it will grow even drier. That's the theory, at least. The only problem is that, so far, these forecasts have not matched reality.

According to the models, subtropical regions, in particular, are expected to grow drier, with new arid zones appearing in the southern United States, South Africa and Mediterranean countries such as Greece, Italy and Spain. Real measurement data from the last 60 years, though, show no such trend toward aridity. Those regions do experience frequent dry periods, but not more often than they have in the past. One possible explanation is that the slight global warming that has occurred so far is not yet enough to cause observable changes in precipitation.

Wind is another area where the IPCC is expected to retract previous warnings. There has been widespread concern that increased global warming could bring about more serious storms, but current long-range forecasts don't suggest such a trend. In fact, the number of hurricanes each year is expected to drop, although peak winds in tropical storms may increase somewhat.

The forecasts for moderate latitudes are even more unambiguous. In regions outside the tropics -- Central Europe, for example -- storms will become neither more frequent nor more serious.

It's certainly a mixed bag, though obviously no one knows for sure just what a global temperature rise of 3 degrees over 200 years will do.

 

[gturner]

The draft finally gives mention to solar forcing, which correlates well with past climate changes where we have isotope data, but then the authors say they don't like some of the theories to explain the magnitude of the effect, and thus discount the effect. IPCC science - backwards as usual. We might as well go back to Aristotle. "We don't understand the mechanism, so we'll pretend the observations don't exist."