Rating: 
Summary: ROLLS OVER AND PLAYS DEAD IN LAST TWO CHAPTERS
Review: A fairly well written book considering a scientist authored it. (I felt the book was mis-titled. It should have been: "THE CORE(S) OF DISCOVERY"). Mr. Alley articulates and delineates -- down to the last cubic centimeter -- what ice core history has to tell us. Then he caves in and spreads out like the Nile Delta, when it comes time for a summary and deft conclusion(s). After years of painstaking study, double-checking, and anal-type accuracy, documenting that Earth is at the cusp of ABRUPT CLIMATE CHANGE, Alley pretty much sums up with: '...it could happen tommorrow or maybe not for a thousand years -- who knows...'. Heavens, we knew that before they ever started drilling holes in Greenland!! I was left flattened, disappointed, and pretty scared. I do not think he was allowed to publish a timeline of when he really predicts ABRUPT CLIMATE CHANGE will happen.
Rating:
Summary: Not like the cubes in your fridge
Review: Alley joins the growing number of field scientists relating their experiences and the research performed by them. In his case the field is the top of the Greenland Ice Cap. The research is the study of ice patterns stretching back over 100 000 years. What do these patterns tell us? Need we care? He explains detail with clarity and detail how the research is done, and describes what has been revealed by it. What those finds tells us of the past, present and might mean in the future become the remainder of the book. One thing stands out vividly - climate not only varies more than we believe, it changes far more rapidly than we expected.The Greenland Ice Cap bears an astonishingly detailed record of environmental events. Far more than simply packed snow, this massive archive keeps information about distant volcanic events, how much salt is in the sea water and what kind of winds played over the Earth's surface. Even conditions in distant Asia are recorded here in the dust layered within the ice. There are records of long periods of cold and announcements about continental drifting. Alley explains all the elements that must be examined in the layered ice, how they came about and why they occurred. Earth's solar orbit, its tilting angle to the sun, and the slow precessional rotation of the poles. All these motions are further complicated by oceanic currents, wind patterns and humidity levels. Alley describes tracking some of the variations as "following a roller-coaster with a man bouncing on a bungee cord while spinning a yo-yo". It's a dizzying picture and he's quick to point out that many points remain unexplained. Is this an issue that should concern us? Human history from the onset of agriculture has been a period of unusual stability. The future, Alley tells us, is highly uncertain. The only certainty is that climate will change - it must. Global warming is a fact, not a supposition, he asserts. One result of it will be the addition of fresh water into the "conveyor belt" of oceanic water exchange. The North Atlantic is the key site. Interruption of that exchange by extra meltwater from North America will intrude - chilling northern Europe. Human populations will be affected differently in various places. There will be winners and losers in this situation, but the losers will certainly outnumber the winners. How severe will the changes be? "I don't know". How fast will the changes come about? "I don't know". His lack of knowledge doesn't stem from lack of effort. He reminds us that the information gleaned from Greenland is still new. There's much to learn and do. He calls to us: "Send us your brightest students to help, and cheer them on!". A good piece of advice, but not one likely to be taken by a people choosing business instead of science.
[stephen a. haines - Ottawa, Canada]
Rating:
Summary: Not like the cubes in your fridge
Review: Alley joins the growing number of field scientists relating their experiences and the they research perform. In his case the field is the top of the Greenland Ice Cap. The research is the study of ice patterns stretching back over 100 000 years. What do these patterns tell us? Need we care? He explains detail with clarity and detail how the research is done, and describes what has been revealed by it. What those finds tells us of the past, present and might mean in the future become the remainder of the book. One thing stands out vividly - climate not only varies more than we believe, it changes far more rapidly than we expected.
The Greenland Ice Cap bears an astonishingly detailed record of environmental events. Far more than simply packed snow, this massive archive keeps information about distant volcanic events, how much salt is in the sea water and what kind of winds played over the Earth's surface. Even conditions in distant Asia are recorded here in the dust layered within the ice. There are records of long periods of cold and announcements about continental drifting. Alley explains all the elements that must be examined in the layered ice, how they came about and why they occurred. Earth's solar orbit, its tilting angle to the sun, and the slow precessional rotation of the poles. All these motions are further complicated by oceanic currents, wind patterns and humidity levels. Alley describes tracking some of the variations as "following a roller-coaster with a man bouncing on a bungee cord while spinning a yo-yo". It's a dizzying picture and he's quick to point out that many points remain unexplained.
Is this an issue that should concern us? Human history from the onset of agriculture has been a period of unusual stability. The future, Alley tells us, is highly uncertain. The only certainty is that climate will change - it must. Global warming is a fact, not a supposition, he asserts. One result of it will be the addition of fresh water into the "conveyor belt" of oceanic water exchange. The North Atlantic is the key site. Interruption of that exchange by extra meltwater from North America will intrude - chilling northern Europe. Human populations will be affected differently in various places. There will be winners and losers in this situation, but the losers will certainly outnumber the winners. How severe will the changes be? "I don't know". How fast will the changes come about? "I don't know". His lack of knowledge doesn't stem from lack of effort. He reminds us that the information gleaned from Greenland is still new. There's much to learn and do. He calls to us: "Send us your brightest students to help, and cheer them on!". A good piece of advice, but not one likely to be taken by a people choosing business instead of science.
[stephen a. haines - Ottawa, Canada]
Rating:
Summary: Covers a lot in a small space
Review: Although I never completed the degree, I have most of a baccalaureate in geology. Since paleontology and earth history were my main interests, the title Two-Mile Time Machine: Ice Cores, Abrupt Climate Change, and Our Future by Richard B. Alley naturally caught my eye. The book is an excellent exposition on the recent data collection from ice cores obtained from the more stable portions of the Greenland ice sheet. I had come across this data source before while on a geologic field trip on Santorini helping with research on the volcanic activity that occured there during the Minoan period. It had been information from this source that had helped to date the volcanic event, so I was particularly interested in learning more about how it was obtained and about its reliability. In part two of the text, the author lucidly describes the rationale behind the selection of ice and of Greenland as an "archival" source. He discusses the methods in and problems of obtaining and preserving the material intact and uncontaminated and the methods of analysis that produced the data. Throughout the following chapters, he lays out for the reader the thinking that went into its interpretation and how this information can be used as a paradigm with which future outcomes of climate change might be predicted. Because Alley, a professor of geoscience at Penn State, took an actual part in all of these proceedings and is an active scientist himself, he is well positioned to give an informative account of the topic. He also has a readable writing style which many such individuals do not. Although I felt that his attempt to "get down to" the level of his non-technical audience was sometimes a little patronizing, I did think that his explanations of some of the physical systems was very clear. The description of the events leading to and during the Younger Dryas got a little confusing with the comparison to a roller coaster with a bungee jumper and a yo-yo, but by the end of the chapter one still had a fair idea of what he was trying to convey.--I think he was just trying a little too hard. His explanations of important environmental cycles with which I was already familiar--like those of the carbon, the water, the heat distribution, the oceanic and lake water overturn, and atmospheric cycles and those of the Coriolis and Milankovich effects--were very clear. In fact they were clearer than some textbook descriptions I've read. Although I had read of the effects of fresh water on the North Atlantic "conveyor belt" and its subsequent effect on global climate, I had not encountered the Dansgaard-Oeschger cycle or the Heinrich-Bond oscillations in my reading in the past. The author's presentation was therefore of interest to me. For most readers, part five will probably be of greatest interest. Here the author puts what is known or suspected of climatic mechanics to work in predicting possible impacts of human activity on global climate and the world's population. Here too he points out the nature of the scientific method and its limitations. He is quite clear that some of what he states in his final analysis with respect to the future is personal opinion and not science. As an earlier reviewer points out, the book is an excellent portrayal of how science works, particularly in the aspects of framing a problem and a means of approaching it experimentally, and interpreting the data that arises therefrom. I found it a very entertaining book.
Rating:
Summary: Covers a lot in a small space
Review: Although I never completed the degree, I have most of a baccalaureate in geology. Since paleontology and earth history were my main interests, the title Two-Mile Time Machine: Ice Cores, Abrupt Climate Change, and Our Future by Richard B. Alley naturally caught my eye. The book is an excellent exposition on the recent data collection from ice cores obtained from the more stable portions of the Greenland ice sheet. I had come across this data source before while on a geologic field trip on Santorini helping with research on the volcanic activity that occured there during the Minoan period. It had been information from this source that had helped to date the volcanic event, so I was particularly interested in learning more about how it was obtained and about its reliability. In part two of the text, the author lucidly describes the rationale behind the selection of ice and of Greenland as an "archival" source. He discusses the methods in and problems of obtaining and preserving the material intact and uncontaminated and the methods of analysis that produced the data. Throughout the following chapters, he lays out for the reader the thinking that went into its interpretation and how this information can be used as a paradigm with which future outcomes of climate change might be predicted. Because Alley, a professor of geoscience at Penn State, took an actual part in all of these proceedings and is an active scientist himself, he is well positioned to give an informative account of the topic. He also has a readable writing style which many such individuals do not. Although I felt that his attempt to "get down to" the level of his non-technical audience was sometimes a little patronizing, I did think that his explanations of some of the physical systems was very clear. The description of the events leading to and during the Younger Dryas got a little confusing with the comparison to a roller coaster with a bungee jumper and a yo-yo, but by the end of the chapter one still had a fair idea of what he was trying to convey.--I think he was just trying a little too hard. His explanations of important environmental cycles with which I was already familiar--like those of the carbon, the water, the heat distribution, the oceanic and lake water overturn, and atmospheric cycles and those of the Coriolis and Milankovich effects--were very clear. In fact they were clearer than some textbook descriptions I've read. Although I had read of the effects of fresh water on the North Atlantic "conveyor belt" and its subsequent effect on global climate, I had not encountered the Dansgaard-Oeschger cycle or the Heinrich-Bond oscillations in my reading in the past. The author's presentation was therefore of interest to me. For most readers, part five will probably be of greatest interest. Here the author puts what is known or suspected of climatic mechanics to work in predicting possible impacts of human activity on global climate and the world's population. Here too he points out the nature of the scientific method and its limitations. He is quite clear that some of what he states in his final analysis with respect to the future is personal opinion and not science. As an earlier reviewer points out, the book is an excellent portrayal of how science works, particularly in the aspects of framing a problem and a means of approaching it experimentally, and interpreting the data that arises therefrom. I found it a very entertaining book.
Rating:
Summary: Insider look at ice coring in Greenland and what it means
Review: I have been researching Greenland for a project I am working on and heard about ice coring in Greenland a couple of months ago. As I soon discovered, Greenland also plays quite an important role in the climate change discussion. I wanted to learn more.
This book served my purpose.
I found this book easy to read. It kept me engaged from the start when I started to read it. The author clearly and simply describes many of the methods used to analyze ice cores. All while relating them to the bigger picture and also comparing the analysis of ice cores with other methods of analyzing past climate such as tree rings or layers of sediments in bodies of water - past or present.
I appreciated the simple analogies (and charts) throughout the book. While some readers may think they are too simplistic, I think they are perfect. I don't think the book is aimed at people already familiar with the subject but at the layman / general reader. That's what one of the quotes says on the back too. The author's sense of humor also shows in his writing. This is good.
While reading, there were some passages where I started to get confused. Thankfully, the author realized that it might come across that way and quickly moved to summarize the recently presented information.
While the illustrations are good, improvements to the book might be more maps showing the locations he talks about. I only recall a map of Greenland. It wasn't a problem for me since I have studied Greenland intensively recently and I also have traveled widely and have a good knowledge of geography, but I suspect some might get confused.
The discussion on the conveyor belt shutting off could have been more succintly written and concluded better. While the author explains how a section of the world will cool if the conveyor is shut off (Europe), he doesn't talk much about how other parts will warm. It seems to be only in general terms. "The South Atlantic will be warmer." "The monsoon will be affected in Asia."
On the positive side - the author does note that we might/should be entering an ice age cycle, he does point out that our actions in warming the planet will easily be greater than the natural decline in temperature that would otherwise take place. Though I also wonder how a significant drop in global temperature 10-15F over a few years (Something which the ice core shows has happened in the past) would contrast with our actions in warming the planet. More hypothesis would be appreciated.
A good overall explanation of climate change including the conveyor belt is on the Union of Concerned Scientists website.
I would have also appreciated a little more discussion on the ice coring efforts in Antarctica as the author has been there several times also. It is discussed and compared, but I feel more could have been written about it although Antarctica isn't the main focus of the book.
In summary, this is an excellent and accesible read on the science of ice coring and what it tells us about the past and why the Greenland ice cores are so important. The book stumbles a bit on discussing scenarios in the future based on the findings. Though I feel the author may have deliberately left this out.
Rating: 
Summary: Deep Science, and Truly Pertinent
Review: I have lived in a good many places in the world, and I think I have never lived in a place where people didn't voice the witticism, "If you don't like the weather here, stick around twenty minutes and it'll change." We are quite used to rapid changes in weather, and all of us seem fascinated by the way one day is different from another, or at the mistakes the weather forecasters make. Only over the past few decades, however, have scientists been able to get a grip on something else fascinating: climate. Ice in Greenland has been piling up year by year for 100,000 years. This ice carries inside it a record of the climate that produced each yearly layer. In _The Two-Mile Time Machine: Ice Cores, Abrupt Climate Change, and Our Future_ (Princeton University Press), Richard B. Alley, who has done research in Greenland and Antarctica, gives us a view of his narrow and deep studies, and tells us why they are important. It is the first book for the layman to show how climate historians are doing their jobs, drilling five inch cores two miles down, and analyzing the ice in many clever ways. For most of the 100,000 year record, the climate has had wild jumps, centuries of cold followed by abrupt heating. Humans have lived in an anomalous period of stability. There have been climate changes that influenced human life, like the warm spell that lured the Vikings to Greenland and the cold that drove them out, but these represent one degree shifts shown in the recent ice records. Teensy temperature changes have made what we would consider big climate differences, but when it comes to the wild changes, we ain't seen nothing yet. Yet. Alley devotes the main part of his book, after showing how scientists draw facts out of buried ice, to discussing what drives global climate change over decades and over eons. He is able to paint a vivid, if brief, picture for those who are not acquainted with his field. His comparisons are felicitous, explaining that the ocean loses carbon dioxide when heated just as a carbonated soft drink would, or showing how a glacier pushes Greenland down into the deep, hot, soft rock below like a person sitting on a waterbed full of syrup. He is in no way a scaremonger, and takes the correct tentative tone because we don't have all the information yet. However, he concentrates on a switching mechanism involving the flow of the Atlantic Gulf Stream; it seems that minor changes in temperature or salinity may jam the "conveyor belt" of the oceans as they transfer heat from the equator to northern latitudes. If it does jam, the results for Europe would be disastrous, and it would affect the rest of the world as well. We know about this switch, and there must be others that we do not know about, and all of them may be vulnerable in our current period of stability to being switched off and making the climate careen again. His moderate advice is that climate change is inevitable, that it will trouble more people than it benefits, and that there are reasons to think that what we are doing to the atmosphere may kick it into instability. If we continue, we may well suffer a crash of a climate change that uses up more of our resources than we have; prudence suggests that we all (especially in developed nations) should be trying to reduce our impact per person. We have used the current centuries of stability for all they are worth; if you don't like the weather now, stick around for twenty years or two hundred, because it is going to be quite different.
Rating: 
Summary: Informative, but speculative
Review: In many respects this is an excellent book. The author has a gift for explaining the subject's complexities with down-to-Earth analogies. However, he runs far afield of his primary subject(Greenland ice cores and the clues they offer to past climate change), though in all fairness his subtitle does hint at these excursions. The author provides much useful information on the interconnectedness of Earth systems and their feedbacks, but makes proclamations that are sometimes broad and sweeping, and unsupported by evidence presented in the book. To his credit, he correctly advises scientific caution in drawing conclusions from a limited, but growing data set. He also sounds the warning claxon on abrupt and human-induced climate change (but where is the evidence?) without resorting to pedantry. It is clear from this text that humankind needs to behave more responsibly with respect to our home, the Earth.
Rating:
Summary: Informative, but speculative
Review: In many respects this is an excellent book. The author has a gift for explaining the subject's complexities with down-to-Earth analogies. However, he runs far afield of his primary subject(Greenland ice cores and the clues they offer to past climate change), though in all fairness his subtitle does hint at these excursions. The author provides much useful information on the interconnectedness of Earth systems and their feedbacks, but makes proclamations that are sometimes broad and sweeping, and unsupported by evidence presented in the book. To his credit, he correctly advises scientific caution in drawing conclusions from a limited, but growing data set. He also sounds the warning claxon on abrupt and human-induced climate change (but where is the evidence?) without resorting to pedantry. It is clear from this text that humankind needs to behave more responsibly with respect to our home, the Earth.
Rating:
Summary: Certain Action Must Always Be Based On Uncertain Science
Review: One of the most critical aspects of science appears on page 174 of The Two-Mile Time Machine by Richard B. Alley: ALL scientific ideas are subject to revision; we should never be absolutely sure that the truth has been reached. Old ideas should be tested continually, in an effort to tear them down and replace them with better ones. Ideas that survive this constant attack will be especially robust. Experience shows that if we behave as if these surviving ideas are true, we will succeed.... But, on the other hand, the ideas may be true, they may be reasonable approximations of the truth, or we may just be lucky. In science, no idea, be it speculation, hypothesis, theory, law, model, or FACT, is ever considered to be the final answer. That's the way science works. We ALWAYS act on uncertain answers; we never know if something is the truth with a capital T. The Two-Mile Time Machine is not only an excellent exposition of the use of ice core [and other] data to figure out the recent and future climate situation on Earth, but it is an excellent exposition of how science in general works. Richard B. Alley, a participating scientist in the GISP2 ice core project in Greenland, has written an easy-to-read, but pull-no-punches book on a complicated scientific topic. The book starts out with the basics of coring, dating, and analyzing ice, and takes the reader through to the political, social, and ethical implications of future climate changes, and concludes with Alley's take on what our responses should be. He always states how much uncertainty is attached to any of the ideas he writes about. If a person of a non-scientific background is going to have a complaint about the book, it will probably be that the book goes into too much detail about the evidence supporting the ideas. This book is highly recommended to anybody interested in Earth history, climate, Arctic research, the methods of science, and anybody who wants an excellent science read. The book is especially recommended to anybody interested in or involved in the debate over the future of the Earth's climate. All people involved in this issue need to UNDERSTAND the scientific details. The issue of the Earth's climate future has become way too politicized. Our actions are always based on ideas that have some level of uncertainty, but we must act, because the future of humanity will depend on what we do.
|
