Richard Alley
This book is about how you go about learning the past history of the Earth using the secrets frozen in ice. The flippant title refers to one of my favorite descriptions of a geologist’s job: time traveler. Our job is to understand what has occurred in the past, and communicate that to others. This book is about communicating a specific history revealed through a specific technique: the climate history recorded in ice trapped in ice sheets over the past million or so years.
The stable ice sheets of today owe their existence to a local climate that has more yearly ice accumulation than ice removal. Each year’s snow piles up, with specific differences between the snow deposited during winter and that during summer. This allows direct dating of layers, analogous to the new deposition each year of tree rings. These snow layers are not foolproof; perhaps a time of high wind scours a year away, or an especially dry year isn’t even recorded. These problems increase the farther down you go, as the layers thin out under the pressure of the layers above. Even worse than thinning, they begin to flow out towards the continental edges, increasing the noise to signal ratio.
While any geoscientist is familiar with the basics of how ice cores are used, Alley brings us to Greenland with detailed descriptions of what it was like to be on the ground. This is one of the most powerful parts of the book; it’s easy to look at squiggly lines in a paper and nod serenely in wise acknowledgement at their meaning, but it’s a different thing to understand just how hard that data was to collect. This kind of situation can certainly be engaging (see “The Big Bang Theory”, Season II, finale) but rarely do we get the inside story about how it goes down. That kind of isolated situation is the perfect setup for really engaging stories, but the most sordid tale recounted is that of previous year’s scientists driving a snowmobile into an area they weren’t supposed too. You can help but assume that there were more scandalous tales to be told- but whether they didn’t happen by some chance of group dynamics, or Alley’s careful avoidance of the subject, some more interpersonal conflict might have made the book a bit more engaging.
The key portion of this book, just described, finishes up about halfway through. The rest is filled with an increasingly bland description of the data and what it means. Classic literary theory says that a story should have a beginning, middle, and end – the middle, especially should be characterized by increasing tension which is burst at the end and resolved. Straying from this classic formula can be done, and successfully, but more often than not the classic formula is there for a reason: it works. The fact that this is a science book is not an excuse; Stephen J. Gould’s Wonderful Life not only fits in a beginning, middle and end – but also a hero, the noble (at least to us!) Pikaia. Richard Dawkins Selfish Gene weaves a tale about flesh robots and probability into an expose about altruistic behavior, and when the conventional narrative breaks down, he finishes with a bunch of nearly stand-alone chapters that each hit hard – most notably, he coins the word meme – which has entered the popular consciousness regarding the internet. Alley, in contrast, writes competently about the science but manages not to write an engaging book.
The second half of this book does a good job of explaining the science of ice cores, but doesn’t do it better than I probably could have just reading the abstracts of the important papers from the past decade. In that aspect, I’d recommend this book for the educated layman who wants more, but not for a scientist with the knowledge to understand the primary literature (no matter how far afield). Alley does conclude with an excellent dissection of the current state of climate science in the public sphere – which may very well be worth the price of admission.
