PreFACe 1. Pre Am ble 2. the GrAnD uncon trolled exper i ment

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1 PREFACE 1. PreAmble When George Fried rich Han del wrote that most famous piece of sacred music, The Mes siah, in 1741, he searched for a term to describe it. It was not a mass or a requiem, or a hymn. It was an ora to rio, but not really like the oth ers he had written. He wrote The Mes siah in less than a month. He adver tised its first per formances as A Musical Enter tain ment. This book is both about sci ence and per sonal expe ri ence. But it is not like other books about the sci ence of cli mate and it is not a textbook. It is full of sto ries about sci en tific dis cov ery. And it is also an auto bi og ra phy. I started to write it in the late fall of 2007 after the great Arc tic Ice Melt back had become known. I thought I could fin ish it in three months at most. Hav ing worked in the field of pa leo cli ma tol o gy, the study of ancient cli mates, for over 30 years, I thought I had a good under stand ing of the topic. But as I went along I dis cov ered that I needed to know more of the basic sci ence involved in order to prop erly explain it to my non-sci en tist neigh bors. Instead of three months it took four years of research into the his tory of sci ence and how we have come to our pres ent under stand ing of the way the world works. And I guess that in this case the end prod uct is best described as A Schol arly Enter tain ment. 2. The Grand Uncontrolled Experiment The idea that humans might be able to alter the cli mate is older than you may think. The Brit ish col o nists of North Amer ica found its cli mate to be rather unpleas antly hot and humid. Thomas Jef fer son sug gested that it might be improved, that is made to be more like that of England, by cut ting down the forests. The idea that the burn ing of fos sil fuels, thereby releas ing CO 2 into the atmosphere and affect ing the cli mate, arose at the end of the 19th century. It was suggested by Swed ish sci en tist Svan te Arrhe nius, who thought that the ensu ing warm ing would be good for the Nor dic coun tries, mak ing for a longer grow ing season. The hypothesis of atmospheric CO 2 con cen tra tions as a con trol of cli mate enjoyed brief pop u lar ity among geol o gists but was soon for got ten. ix

2 x PREFACE A Brit ish steam engi neer, George Cal lend er, kept track of ris ing tem per a tures and CO 2 con cen tra tions dur ing the first half of the 20th century, not ing the good cor re la tion between the two. No one paid much atten tion. Then, in 1956, Gilbert Plass, a Canadian physicist who had been made a full professor at Texas A & M University, made a solid argument that atmospheric CO 2 was the likely regulator of the Earth s climate over time. He also suggested that the continued burning of fossil fuels might tend to dive the planet toward a global tropical climate in the not-too-distant future. His paper in American Scientist is a true classic, and you should read it. The web address where you can download a free copy is at the end of this preface. A year later Roger Rev elle and Hans Su ess, both sci en tists at the Scripps Institu tion of Ocean og ra phy in La Jolla, Cal i for nia, pub lished what has become the clas sic paper on the pos si ble future effects of human activ i ties result ing in increasing the con tent of car bon diox ide (CO 2 ), a green house gas, in the atmo sphere. Their 1957 paper included the state ment Within a few cen tu ries we are return ing to the atmo sphere and oceans the con cen trated organic car bon stored in sed i men tary rocks over hun dreds of mil lions of years. This exper i ment, if ade quately doc u mented, may yield a far-reach ing insight into the pro cesses determining weather and climate. Roger and Hans thought we were going to make only a minor mod i fi ca tion of the Earth s cli mate with this addi tion of fos sil car bon. How ever, the exper i ment was more com plex than they real ized. The addi tion of CO 2 to the atmo sphere is only one of sev eral changes humans are mak ing to the planet Earth. Over the past two and a half cen tu ries since the begin ning of the Indus trial Rev o lu tion, human activ i ties have become increas ingly impor tant in affect ing con di tions on the sur face of the Earth. Four human-driven fac tors are forc ing regional and global environmental change: 1. Increas ing lev els of atmo spheric green house gases; 2. Clear ing of for ests for agri cul ture and con struc tion of build ings and roads on a scale that affects the amount of the sun s energy reflected or absorbed by our planet; 3. Replace ment of plants that freely tran spire and return water to the atmo sphere by water-con serv ing plants that grow faster and now form the basis for our food sup ply in many parts of the world; and 4. Min ing of min er als and extrac tion of petro leum with con com i tant release of nutrients and poisonous materials into the environment. All of the above four fac tors are closely related to the growth of the human pop u la tion of the planet, the devel op ment of civ i li za tion, and the need for increasing food sup plies. Of these four, only the first has been seri ously addressed in attempts to assess its affect on future cli mate change. This is because green house gas con cen tra tions have a global effect. The other fac tors have regional effects but may over the long run have irre vers ible global impli ca tions. To assess the global effects of the addi tion of green house gases to the atmosphere, an Inter gov ern men tal Panel on Cli mate Change (IPCC) was estab lished

3 PREFACE xi in Its par ents are the World Mete o ro log i cal Orga ni za tion (WMO) and the United Nations Envi ron ment Programme (UNEP), both agen cies of the United Nations. Their thrust has been to doc u ment fac tors related to cli mate, and to make pro jec tions about what changes might be expected until the end of this cen tury. The IPCC is an extremely con ser va tive group, to which cli mate sci en tists are advi sory. It has issued four reports, the most recent of which pro jects a global tem per a ture rise between 1.1 C (2 F) and 6.4 C (11.5 F) by the end of this century, accom pa nied by a sea level rise of between 18 and 59 cm (7 to 23¼ inches). These may not sound like large changes, but when the Earth was 6.4 C cooler there was half a mile of ice over Chi cago, and a sea level rise of more than half a meter will dis place more than 50 mil lion people. Unfor tu nately, many cli mate sci en tists and most of the gen eral pub lic do not real ize that even if there were concerted efforts under taken to reduce green house gas emis sions and mit i gate their effects, cli mate change would not end in Geo chem ists who have stud ied the CO 2 sys tem are aware that, depend ing on the mag ni tude of the per tur ba tion, the effects may con tinue for tens to hun dreds of thousands of years. 3. How to Read this Book This book is intended for the lay per son in the United States, although I hope that my sci en tific col leagues and lay per sons else where might also find it inter est ing and amus ing. It is organized to pro vide, first, an intro duc tion to con cepts that are impor tant in thinking about changes on the planet Earth. Then fol lows a gen eral descrip tion of how the cli mate sys tem works. Finally, there is a series of chap ters that dis cuss each aspect of the cli mate sys tem, how they have var ied over time, and whether or not human activ ity can affect them. Depend ing on how much you already know, you can skim famil iar top ics to see if they con tain some thing you did not know. Things you are thor oughly famil iar with you can skip alto gether. I was already work ing on my Ph.D. before some one explained to me that it is a waste of valu able time to read some thing you already know. Most Amer i cans, even those with an engi neer ing back ground, have dif fi culty thinking in terms of the met ric sys tem used in the rest of the world. The Fahr enheit tem per a ture scale is still used in only two coun tries: the US and Belize; the rest of the world uses the Cel sius (= Centigrade) system. Accordingly, although the cita tions of data in the text will be in met ric terms, I always try to include their US or Fahrenheit equivalents in parentheses. I also find that access to the Inter net is more use ful than pages of ref er ences to the technical literature. Where particularly appropriate I refer to some specific Inter net sites, and at the end of each chapter I list some books for those who wish to delve fur ther into the sci ence of cli mate change and other top ics cov ered in this book. Also, the reader can find many use ful illus tra tions and dia grams on the internet by goo gling on a topic. Goo gling for illus tra tions of Sic car Point will bring up a host of pic tures of that (geo log i cally) famous place. You can also fol low my wan der ings using Go ogle Earth. You can make a vir tual visit to Uni ver sity Col lege

4 xii PREFACE in Gow er Street, Lon don, where I was Research Fel low, or GE O MAR (now the Leib nitz Insti tute for Marine Sci ence) in Kiel, where I spent more than a decade, or any of the other places men tioned in the book. Sim i larly, typ ing in the name of some one men tioned in this book, such as W. Broec ker, and using Google Scholar, will bring up a list of pub li ca tions, some of which may be down loaded for free. How ever, there is a caveat about using the Inter net for inves ti gat ing cli mate change. The num ber of web sites that pres ent disinformation or misinformation, particularly regarding carbon dioxide, greatly exceeds those pre sent ing sci en tifi cally valid infor ma tion. Some one wants to keep you burn ing as much fos sil fuel as pos si ble. 4. Pairings Strong cof fee will be help ful through out the book if you are a day time reader. How ever, if you like to read in the even ing, and are over 21, I sug gest that the ear lier chap ters pair well with a Cal i for nia Char don nay or a French Cha blis, the mid dle chap ters with a substantial red, such as Mer lot or Pinot Noir, and the later chap ters with Cab er net Sau vi gnon or a fine Bor deaux. Toward the end you may require a Cognac, Armag nac, or a Marc. There will be indi vid ual sec tions where stron ger drink, such as Scotch, Bour bon, or even a Mar tini may be called for. The very impor tant sec tion in Chap. 2 concerning natural logarithms, exponential growth and decay, and the true mean ing of some every day words is best read with a good Brandy in hand. The two clas sic papers men tioned above can be down loaded for free from the internet: Plass, G., Car bon Diox ide and Cli mate. Amer i can Sci en tist, v. 44, pp Rev elle, R., and Su ess, H. E Car bon diox ide exchange between atmo sphere and ocean and the ques tion of an increase of atmo spheric CO 2 dur ing the past decades. Tel lus, v. 9, pp

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