I’ve pretty much given up on reading the rest of the Nierenberg report (1983). It’s long on words, and I’m short on time. After about 2/3 of the way through the synthesis, it gets pretty wishy-washy. I skimmed chapter 2, which was written by an economist, and it too seems wishy-washy. Although with the predictions of CO2 rise that they give for a “stringent tax” on CO2 starting in 2000 still resulting in CO2 concentration of 660 ppm in 2100, which is still in the “we’re all f—ed” range.

The “stringent tax” is described two ways in the text. In the caption to table 2.18, it is described as a “gradually increasing tax rising linearly from zero to $8 per ton [coal equivalent] between 2000 and 2020, from $8 to $68 per ton between 2020 and 2040, from $68 to $90 per ton between 2040 and 2060, and remaining at $90 per ton thereafter.” In the text, it describes the tax as “plac[ing] 60% surcharges on the prices of fossil fuels”. The “stringent tax” results in a reduced atmospheric CO2 concentration of about 120 ppm from the business as usual scenario over about 120 years.
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Anthropogenic global warming is expected to bring many changes to the world. According to Wikipedia, “[m]ost of the consequences of global warming would result from one of three physical changes: sea level rise, higher local temperatures, and changes in rainfall patterns.” The most obvious consequence of the three is higher surface temperatures. And this is the consequence that the media focus on the most.

Precipitation changes can also be fairly easily conceptualized. If the addition of greenhouse gases changes the heat distribution of the planet, it is likely that regional weather patterns will change as well. Changes in both temperature and precipitation are easy to understand for everyone. However, the third consequence is more difficult, especially those of us who don’t live near the coast.
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I’ve talked about the issue of teaching climate change in schools recently, and yesterday I came across a blog that illustrates my concern at The “More” Child.

The author of this blog post is a mother of two children who appear to be in 5th and 7th grade. The antecdote told in the post is about the elder child. It turns out, she has been exposed to a variety of sources of information that has led her to some unfortunate conclusions. The information presented paints the picture that the child is afraid that the world will change drastically by the time she is older.

For one thing, it is not too late. Dr. James Hansen has stated on many occasions, including in his recent op-ed in the Boston Globe, that action we take now can reverse the changes we have seen so far. However, even if we had experienced irreversible climate change, that doesn’t mean we shouldn’t do anything about it. And we aren’t; there are intelligent people working to solve the problem.
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This is a short summary of a talk recently given by Dr. Bette L. Otto-Bleisner.
[Sorry for the short and infrequent posts lately. It's that time of year. ;-)]

Dr. Bleisner first talked about the proxy records from the last interglacial and how they suggest that at that time it was 3-5C warmer than it is now. And through proxy records of the Greenland ice sheet, the summit of Greenland was still covered at the LIG, but the southern tip was ice-free. Sea levels were more than 5 meters higher than they are today. At Bermuda they were from 5-6 meters higher than present. McCulloch and Esat [2000] report the somewhat controversial finding that sea levels rose as much as 1 meter per century.

She also talked about the Milankovitch cycles as climate forcings. She used the CCSM2 model forced by the Milankovitch cycles and greenhouse gases to find that the arctic was not ice-free during the last interglacial. That only 2.2-3.4 meters of sea level rise was due to ice melt from the Greenland ice sheet, but sea levels rose by 4-6 meters, so the rest must be from Antarctica. Cuffey and Marshall [2000] found the sea level rise during the LIF was “mainly from disintegration of the West Antarctic ice sheet3, with model studies attributing only 1–2 m of sea-level rise to meltwater from Greenland”.

References:
Cuffey, K. M. and Marshall, S. J.: 2000, Substantial Contribution to Sea-level Rise During the Last Glaciation from the Greenland Ice Sheet, Nature 404, 591–594.

Malcolm T. McCulloch and Tezer Esat, The coral record of last interglacial sea levels and sea surface temperatures, Chemical GeologyVolume 169, Issues 1-2, , 15 August 2000, Pages 107-129.