, elaborating on what climate change will mean. Although the dust cover exhibits an eye-grabbing image of New York City under water, she is not actually projecting that future. Her interest is not so much in discussing the future weather as in pointing out the issues associated with the future weather. In that light, her subtitle is more representative of the content of the book: Heat Waves, Extreme Storms, and Other Scenes from a Climate-Changed Planet. The message she wants the reader to take away is that the climate is changing and responses to those changes will be required. We should begin to address them now to limit further damage.The first part is a short and focused description of what is happening to our climate and why. The second part—the largest and most interesting part—takes us to seven locations in the world that will be affected by the changing climate. One learns a considerable amount about the ecology of each location in order to understand why climate modification will become important. She picks a 40 year window in which to make her evaluations and predictions. This period of time is not long enough to reach the direst conditions predicted by climate models, but it is long enough to cause effects that must be addressed. She hopes they will be addressed in anticipation rather than in response. The seven locations are:
The Sahel, Africa
The Great Barrier Reef, Australia
Central Valley, California
The Arctic, Inuit Nunaat, Canada
The Arctic, Greenland
Dhaka, Bangladesh
New York, New York
The two main things the author wishes to accomplish in the first section of the book are to explain how the buildup of carbon dioxide is changing our climate, and to convince the reader that climate modelers can provide credible predictions of the future. This has to be accomplished in language that can be understood by the lay reader. I thought this was the weaker section of the two. The description of the role carbon dioxide plays in the atmosphere is well known, but the interchange between earth and air is complex and not familiar to most. The author’s attempt to simplify and explain with her brief description of what she referred to as the "carbon cycle" is unconvincing and perhaps misleading.
She does a good job of presenting the nature of the modeling that climatologists do to make predictions. She attempts to produce credibility by claiming the scientists are able to do "hind-casting" —a term I wish had not been invented. It is typical for computer modelers to test their models by trying to reproduce past events with known conditions and known results. Generally your model will really be a collection of individual models, some of which are well understood and some which are either not amenable to numerical solution or for which needed physical parameters are lacking. If that is the situation, and I suspect it is for the climate scientists, you go through a process of "benchmarking" against past data. This benchmarking process can involve fiddling with these models or data that are not firmly established in order to arrive at a calculation that matches the data. Performing this procedure on multiple sets of data gives one confidence that the models are well-behaved. This is the best you can do in order to come up with a predictive tool, but this is not the same process as making a "hind-cast." Even if you accept the hind-cast scenario, these models are verified in the past while they need to be utilized in a future with, perhaps, different conditions and different physical sensitivities. I do not mean to harp too much on this and I do not want to appear to be on the side of the climate-change deniers. It is just that I have an interest in this type of modeling and a healthy respect for the existence of "unknown unknowns." The author would like us to believe that climate forecasting is as reliable as our regular weather forecasts. We each can decide for ourselves how comfortable that makes us feel.
I think the author’s major contribution comes in the second section. The descriptions of the local ecologies at the eight sites are interesting and informative. The conditions are the same for everyone: rising sea levels, rising temperatures, more extreme storms and temperature conditions leading to either floods or droughts or both. What I appreciated most was the way in which she laid out the options one would have in dealing with the changing climate. At all locations there were people in place trying to plan for the changing conditions. Cullen will perform a valuable service if she succeeds in raising the public awareness on these matters. In general, there are actions that can and must be taken if the regions are to have a chance at maintaining a viable lifestyle. Only poor Bangladesh seems destined for unavoidable disaster.
New York is a good example of a location where one can foresee where the problems will lie. Rising temperatures mean hotter summers and higher demand for electricity. If the grid is not fortified there will inevitably be frequent brownouts. Manhattan Island has a good deal of land and infrastructure that are near or below sea level. Flooding is already a problem with storm drainage being barely capable of handling normal events. The author raises the threat of not only more extreme storms, but the prospect of a category 3 or 4 hurricane hitting the city in the future. This prospect, coupled with rising sea levels, suggests the city will ultimately have to construct a sea wall to protect itself from surging waters.
Making New York a viable place to live in the anticipated future will require an enormous investment in rebuilding and upgrading its infrastructure. If anyone wonders where the jobs of the future might come from, herein lies a possible answer. The only question will be how to pay for it. I am not sure how one builds an economy around public infrastructure spending.
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