The last estimates have been disputed by Michael Mann, another well known climate scientist. Papers relating to the dispute are referenced in the book and are linked in Hansen Mann warming prediction dispute links.

There are many interesting interviews and descriptions of climate related programs in the book, including analysis of economic and political aspects. Particularly attractive are hopes for good carbon dioxide extraction from the ocean leading to increased reduction from the atmosphere. He has extensive material on geoengineering possibilities such as using sulpher dioxide in the stratosphere to reflect more sunlight and cool the earth. He explains the nervousness around even discussing this topic, let alone undertaking research, but has come to the conclusion that something like it could well be necessary. If the inexorable (my word) increase in atmospheric CO2 continues as at present, much of the earth will become unliveable. He treats these topics with a high degree of sensitivity for both population and political issues.