This sure caught my eye:

The Intergovernmental Panel on Climate Change (IPCC) report released in Paris on Friday predicts that temperatures are probably going to increase by 1.8 to 4 degrees Celsius by the end of the century. It also said sea levels would probably rise by between 28 and 43 centimeters (11 to 17 inches).

"Once in awhile we get shown the light, in the strangest of places, if we look at it right" - Hunter/Garcia

I haven't read the report, but I would very much like to know if it has been updated and changed so it's not anymore a rag with the predictive power of a squirrel.

I am of course talking about the extreme overestimation in the last report of the amount of oil&gas available in the crust for us to burn.

Peak oil is not an energy crisis. It is a liquid fuel crisis.

is anyone going to take it serious? Looks like the German government might be (from Duetsche Welle): Germany Boosts Investment in Climate Change Research

Always count on the CDU to be dublicitous... What made a splash in the German media was that some low-ranked CDU member brought up (again) general speed limits on German highways, but Merkel promptly dismissed it.

_{*Lunatic*, n.
One whose delusions are out of fashion.}

Will read & report back.


She believed in nothing; only her skepticism kept her from being an atheist. -- Jean-Paul Sartre

Haven't had time to read the whole report, but I scanned the policy makers report and compared it to the third assesment in order to get the most crucial data (the estimated range of surface warming).

The IPCC report contains 6 different scenarios on climate change. These scenarios are taken from the IPPC's special report on emissions scenarios of 2000. Here is an outtake of that report on these scenarios (this is crucial for understanding the data).

By 2100 the world will have changed in ways that are difficult to imagine - as difficult as it would have been at the end of the 19th century to imagine the changes of the 100 years since. Each storyline assumes a distinctly different direction for future developments, such that the four storylines differ in increasingly irreversible ways. Together they describe divergent futures that encompass a significant portion of the underlying uncertainties in the main driving forces. They cover a wide range of key "future" characteristics such as demographic change, economic development, and technological change. For this reason, their plausibility or feasibility should not be considered solely on the basis of an extrapolation of current economic, technological, and social trends.

• The A1 storyline and scenario family describes a future world of very rapid economic growth, global population that peaks in mid-century and declines thereafter, and the rapid introduction of new and more efficient technologies. Major underlying themes are convergence among regions, capacity building, and increased cultural and social interactions, with a substantial reduction in regional differences in per capita income. The A1 scenario family develops into three groups that describe alternative directions of technological change in the energy system. The three A1 groups are distinguished by their technological emphasis: fossil intensive (A1FI), non-fossil energy sources (A1T), or a balance across all sources (A1B).
  
• The A2 storyline and scenario family describes a very heterogeneous world. The underlying theme is self-reliance and preservation of local identities. Fertility patterns across regions converge very slowly, which results in continuously increasing global population. Economic development is primarily regionally oriented and per capita economic growth and technological change are more fragmented and slower than in other storylines.
  
• The B1 storyline and scenario family describes a convergent world with the same global population that peaks in midcentury and declines thereafter, as in the A1 storyline, but with rapid changes in economic structures toward a service and information economy, with reductions in material intensity, and the introduction of clean and resource-efficient technologies. The emphasis is on global solutions to economic, social, and environmental sustainability, including improved equity, but without additional climate initiatives.
  
• The B2 storyline and scenario family describes a world in which the emphasis is on local solutions to economic, social, and environmental sustainability. It is a world with continuously increasing global population at a rate lower than A2, intermediate levels of economic development, and less rapid and more diverse technological change than in the B1 and A1 storylines. While the scenario is also oriented toward environmental protection and social equity, it focuses on local and regional levels.

The estimation in the third assessment report (TAR) contains a range of estimates on these scenarios that runs from 1.4 to 5.8 degrees celcius depending on different models. The estimation in the fourth assessment report (AR4) runs from 1.1 to 6.4 degrees, including estimates of likely scenarios. Such estimates were not available in the third assessment report, however, so these numbers represent different analyses.

I'll hazard the guess that the "best estimates" for the scenarios in AR4 can be compared to the harmonised estimates in TAR. Below are the numbers (can't be bothered with a table right now, so the order is scenario: TAR harmonised, AR4 best)

B1: 2.0, 1.8
A1T: 2.5, 2.4
B2: 2.7, 2.4
A1B: 2.9, 2.8
A2: 3.8, 3.4
A1FI: 4.5, 4.0

This represents something of a downward adjustment. On the other hand, the generalised range of "likely" temperature changes according to the policy makers summary is 2 to 4.5 degrees, which is the exact same range as that for the harmonised estimates for the scenarios in the TAR.

I'd hazard a guess that the high resource estimates Starvid refers to (whether they are right or wrong) are only really relevant for the A1FI scenario, and for that scenario there is the largest downward adjustment so maybe they're now using lower estimates than in 2001?

Another issue that has been noted is the sea level rise, which is adjusted downward somewhat from the TAR. However, this is in part due to an exclusion of changes due to melting glaciers, ice shelfs etcetera (see here). The uncertainty there is said to be too high.