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Tropical cyclone history – part I: How reliable are past hurricane records?

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Guest Commentary from Urs Neu

When discussing the influence of anthropogenic global warming on hurricane or tropical cyclone (TC) frequency and intensity (see e.g. here, here, and here), it is important to examine observed past trends. As with all climate variables, the hurricane record becomes increasingly uncertain when we go back in time. However, the hurricane record has some peculiarities: hurricanes are highly confined structures, so you have to be at the right place at the right time to observe them. Secondly, hurricanes spend most of their life in the open oceans, i.e. in regions where there are very few people and no fixed observations. This means that the reliability of the long-term hurricane record is dependent on who was measuring them, and how, at any given time. The implementation of new observation methods, for example, might have altered the quality of the record considerably. But how much? This crucial question has been widely discussed in the recent scientific literature (e.g. Chang and Guo 2007, Holland and Webster 2007, Kossin et al. 2007, Landsea 2007, Mann et al. 2007). Where do we stand at the moment? This post will concentrate on the North Atlantic, which has the longest record.

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Antarctica is Cold? Yeah, We Knew That

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Translations: (Español)

Guest commentary from Spencer Weart, science historian

Despite the recent announcement that the discharge from some Antarctic glaciers is accelerating, we often hear people remarking that parts of Antarctica are getting colder, and indeed the ice pack in the Southern Ocean around Antarctica has actually been getting bigger. Doesn’t this contradict the calculations that greenhouse gases are warming the globe? Not at all, because a cold Antarctica is just what calculations predict… and have predicted for the past quarter century.

It’s not just that Antarctica is covered with a gazillion tons of ice, although that certainly helps keep it cold. The ocean also plays a role, which is doubly important because of the way it has delayed the world’s recognition of global warming.

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A day when Hell was frozen

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“Hell train station” I was honoured to be invited to the annual regional conference for Norwegian journalists, taking place annually in a small town called ‘Hell’ (Try Earth Google ‘Hell, Norway’). During this conference, I was asked to participate in a panel debate about the theme: ‘Climate – how should we [the media] deal with world’s most pressing issue?’ (my translation from Norwegian; by the way ‘Gods expedition’ means ‘Cargo shipment’ in ‘old’ Norwegian dialect).

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The IPCC model simulation archive

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In the lead up to the 4th Assessment Report, all the main climate modelling groups (17 of them at last count) made a series of coordinated simulations for the 20th Century and various scenarios for the future. All of this output is publicly available in the PCMDI IPCC AR4 archive (now officially called the CMIP3 archive, in recognition of the two previous, though less comprehensive, collections). We’ve mentioned this archive before in passing, but we’ve never really discussed what it is, how it came to be, how it is being used and how it is (or should be) radically transforming the comparisons of model output and observational data.
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What if you held a conference, and no (real) scientists came?

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Over the past days, many of us have received invitations to a conference called “The 2008 International Conference on Climate Change” in New York. At first sight this may look like a scientific conference – especially to those who are not familiar with the activities of the Heartland Institute, a front group for the fossil fuel industry that is sponsoring the conference. You may remember them. They were the promoters of the Avery and Singer “Unstoppable” tour and purveyors of disinformation about numerous topics such as the demise of Kilimanjaro’s ice cap.

A number of things reveal that this is no ordinary scientific meeting:

  • Normal scientific conferences have the goal of discussing ideas and data in order to advance scientific understanding. Not this one. The organisers are suprisingly open about this in their invitation letter to prospective speakers, which states:

    “The purpose of the conference is to generate international media attention to the fact that many scientists believe forecasts of rapid warming and catastrophic events are not supported by sound science, and that expensive campaigns to reduce greenhouse gas emissions are not necessary or cost-effective.”

    So this conference is not aimed at understanding, it is a PR event aimed at generating media reports. (The “official” conference goals presented to the general public on their website sound rather different, though – evidently these are already part of the PR campaign.)

  • At the regular scientific conferences we attend in our field, like the AGU conferences or many smaller ones, we do not get any honorarium for speaking – if we are lucky, we get some travel expenses paid or the conference fee waived, but often not even this. We attend such conferences not for personal financial gains but because we like to discuss science with other scientists. The Heartland Institute must have realized that this is not what drives the kind of people they are trying to attract as speakers: they are offering $1,000 to those willing to give a talk. This reminds us of the American Enterprise Institute last year offering a honorarium of $10,000 for articles by scientists disputing anthropogenic climate change. So this appear to be the current market prices for calling global warming into question: $1000 for a lecture and $10,000 for a written paper.
  • At regular scientific conferences, an independent scientific committee selects the talks. Here, the financial sponsors get to select their favorite speakers. The Heartland website is seeking sponsors and in return for the cash promises “input into the program regarding speakers and panel topics”. Easier than predicting future climate is therefore to predict who some of those speakers will be. We will be surprised if they do not include the many of the usual suspects e.g. Fred Singer, Pat Michaels, Richard Lindzen, Roy Spencer, and other such luminaries. (For those interested in scientists’ links to industry sponsors, use the search function on sites like sourcewatch.org or exxonsecrets.org.)
  • Heartland promises a free weekend at the Marriott Marquis in Manhattan, including travel costs, to all elected officials wanting to attend.

This is very nice hotel indeed. Our recommendation to those elected officials tempted by the offer: enjoy a great weekend in Manhattan at Heartland’s expense and don’t waste your time on tobacco-science lectures – you are highly unlikely to hear any real science there.

The debate is just beginning — on the Cretaceous!

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Most of us who are involved in research related to climate change have been asked at one time or another to participate in public debates against skeptics of one sort or another. Some of us have even been cajoled into accepting. In the pre-YouTube days, I did one against the then-head of the American Petroleum institute at the U. of Chicago law school. Gavin did an infamous one against Crichton and company. People are always demanding that Al Gore debate somebody or other. Both Dave Archer and I have been asked to debate Dennis Avery (of “Unstoppable Global Warming” fame) on TV or radio more than once — and declined. It’s a no win situation. If you accept you give the appearance that these skeptics have something to say that’s actually worth debating about — and give their bogus ideas more publicity. If you decline there are all sorts of squawks that “X won’t debate!” or implications that scientists have declared “the debate” (whatever that is supposed to mean) prematurely closed when in fact it is “just beginning.”

Scientists tend to react badly to demands like this in part because the word “debate” is a rather poor description of the way disagreements get hashed out in science. John Ziman has a good discussion of the extent to which scientific questions are ‘debatable’ here (pdf). In a lawyerly debate, it is fair game for each side to pick and choose whatever argument has the most persuasive force with the audience, jury or judge, without any obligation to consider the force of counter-arguments except insofar as they affect one’s defense against the opponent. Science, in contrast, is a deliberative, cooperative, yet still competitive enterprise, where each side is duty bound to fairly consider all arguments and data that bear on the matter at hand. This is not to say that scientific disputes are necessarily dispassionate or orderly. Indeed, I’ve seen near-fistfights break out over things like the Snowball Earth and the interpretation of Neoproterozoic carbon isotope excursions.

The repeated challenges to debate are probably meant to imply that scientists — and their supporters, including Al Gore — are fixed in their ideas, unreceptive to the new and challenging, and unwilling to defend their ideas in public. This picture is hard to square with how scientists actually behave among themselves. It is not that scientists don’t debate, dispute, disagree about matters related to climate. All those things happen, but not on the subjects that skeptics like Inhofe or Fred Singer or Dennis Avery would like to debate (like whether global warming is mainly caused by CO2 or solar variability, or whether the IPCC warming forecasts represent a credible threat.). Those sorts of things are indeed considered settled science by serious climate scientists. Then, too, scientists are justifiably wary of being drawn into staged debates on such diffuse, ill-defined and largely meaningless topics as whether global warming counts as a “crisis.” In the war of the sound bites, the people who feel free to lie and distort can always win. David Mamet made this point eloquently in Bambi vs. Godzilla. A debate like that is not any kind of debate in the sense understood by scientists.

In fact scientists are probing theories and conceptions all the time, trying to break them. The best way to become famous is to overturn established wisdom, so scientists look hard all the time for opportunities to do this. The problem of Hothouse climate states like the Cretaceous and Eocene is a case in point.

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Uncertainty, noise and the art of model-data comparison

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Translations: (Español) (Chinese (simplified))

Gavin Schmidt and Stefan Rahmstorf

John Tierney and Roger Pielke Jr. have recently discussed attempts to validate (or falsify) IPCC projections of global temperature change over the period 2000-2007. Others have attempted to show that last year’s numbers imply that ‘Global Warming has stopped’ or that it is ‘taking a break’ (Uli Kulke, Die Welt)). However, as most of our readers will realise, these comparisons are flawed since they basically compare long term climate change to short term weather variability.

This becomes immediately clear when looking at the following graph:

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Our Books

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This post is a list of books since 2005 (in reverse chronological order) that we have been involved in, accompanied by the publisher’s official description, and some comments of independent reviewers of the work. We will try and keep this list up to date as and when new books appear. We have also added links to the sidebar with the latest offerings.

Available now:

Happy Reading!

The Hockey Stick and the Climate Wars: Dispatches from the Front Lines, Michael E. Mann (Columbia University Press).

Publisher’s description:

In its 2001 report on global climate, the Intergovernmental Panel on Climate Change of the United Nations prominently featured the “Hockey Stick,” a chart showing global temperature data over the past one thousand years. The Hockey Stick demonstrated that temperature had risen with the increase in industrialization and use of fossil fuels. The inescapable conclusion was that worldwide human activity since the industrial age had raised CO2 levels, trapping greenhouse gases in the atmosphere and warming the planet.

The Hockey Stick became a central icon in the “climate wars,” and well-funded science deniers immediately attacked the chart and the scientists responsible for it. Yet the controversy has had little to do with the depicted temperature rise and much more with the perceived threat the graph posed to those who oppose governmental regulation and other restraints to protect our environment and planet. Michael E. Mann, lead author of the original paper in which the Hockey Stick first appeared, shares the real story of the science and politics behind this controversy. He introduces key figures in the oil and energy industries, and the media front groups who do their bidding in sometimes slick, bare-knuckled ways to cast doubt on the science. Mann concludes with an account of the “Climategate” scandal, the 2009 hacking of climate scientists’ emails. Throughout, Mann reveals the role of science deniers, abetted by an uninformed media, in once again diverting attention away from one of the central scientific and policy issues of our time.


The Climate Crisis: An Introductory Guide to Climate Change. David Archer and Stefan Rahmstorf, Cambridge University Press, 2010.

Publisher’s description:

This book provides a concise and accessible overview of what we know about ongoing climate change and its impacts, and what we can do to confront the climate crisis. Highly illustrated in full colour, it lucidly presents information contained in the Intergovernmental Panel on Climate Change reports, making essential scientific information on this critical topic available to a broad audience.

David Archer and Stefan Rahmstorf – two outstanding scientists – bring us up-to-date on climate science in this remarkable and very readable book. This book deserves to be read by anyone interested in climate change.
–Paul Crutzen, Max Plank Institute for Chemistry, winner of the Nobel Prize for Chemistry for explaining the ozone hole

The key findings of the IPCC, written in plain and simple terms. Great value in informing the public at large about the science underlying the growing challenge of climate change.
-Rajendra Pachauri, Chairman of the IPCC and Director-General of The Energy Resources Institute

They are excellent communicators of the science to the general reader… One hopes for a wide readership for this measured book which clearly and thoughtfully sets out the results of the work of a great many scientists.
– Bryan Walker, Hot Topic, 19 January 2010

Climate Change: Picturing the science. Gavin Schmidt and Joshua Wolfe, W. W. Norton, April 2009

“Climate Change: Picturing the Science is a tour de force of public education. It is simply the best available collection of essays by climate scientists on the nature of human-induced climate change, the ways scientists have come to understand and measure the risks that it poses, and the options that we face….The editors, climatologist Gavin Schmidt and photographer Joshua Wolfe, have produced a collection of essays of uniformly outstanding quality, supported by photographs of beauty and insight.” 

-Jeffrey D. Sachs
Director, Earth Institute at
Columbia University

Publisher’s description:

An unprecedented union of scientific analysis and stunning photography illustrating the effects of climate change on the global ecosystem.

In this groundbreaking book, published by W.W. Norton & Company in April 2009 NASA climate scientist Gavin Schmidt and photographer Joshua Wolfe illustrate as never before the ramifications of shifting weather patterns for human society. Photographic spreads show us retreating glaciers, sinking villages in Alaska’s tundra, drying lakes. The text follows adventurous scientists through the ice caps at the poles to the coral reefs of the tropical seas. Marshalling data spanning centuries and continents, the book affirms the headlines with cutting-edge research and visual records, including contributions from experts on atmospheric science, oceanography, paleoclimatology, technology, politics, and the polar regions.

Reviews

The Long Thaw: How Humans are Changing the Next 100,000 Years of Earth’s Climate, David Archer (Princeton University Press, 2009).

Publisher’s description:

Global warming is usually represented as a hundred-year problem, say to the year 2100. In The Long Thaw, David Archer, one of the world’s leading climatologists, shows how a few centuries of fossil-fuel use will change the climate of the Earth dramatically for hundreds of thousands of years into the future. The great ice sheets in Antarctica and Greenland will take more than a century to melt, we think, but the climate impact from fossil fuel CO2 will last long enough for the ice sheets to respond fully to the warmer climate, changing sea level one hundred times more than the forecast for the year 2100. A planet-wide thaw driven by humans has already begun, but Archer argues that it is still not too late to avert dangerous climate change—if humans can find a way to cooperate as never before.

Reviews:

In this short book, David Archer gives us the latest on climate change research, and skillfully tells the climate story that he helped to discover: generations beyond our grandchildren’s grandchildren will inherit atmospheric changes and an altered climate as a result of our current decisions about fossil-fuel burning. Not only are massive climate changes coming if we humans continue on our current path, but many of these changes will last for millennia. To make predictions about the future, we rely on research into the deep past, and Archer is at the forefront of this field: paleoclimatology. This is the book for anyone who wishes to really understand what cutting-edge science tells us about the effects we are having, and will have, on our future climate.
Richard B. Alley, Penn State University

This is the best book about carbon dioxide and climate change that I have read. David Archer knows what he is talking about
James Hansen, NASA

Books on climate change tend to focus on what is expected to happen this century, which will certainly be large, but they often neglect the even larger changes expected to take place over many centuries. The Long Thaw looks at climate effects beyond the twenty-first century, and its focus on the long-term carbon cycle, rather than just climate change, is unique.
Jeffrey T. Kiehl, NCAR

A great book. What sets it apart is that it expands the discussion of the impacts of global warming beyond the next century and convincingly describes the effects that are projected for the next few thousand years. What also sets it apart is how deeply it takes general readers into the scientific issues of global warming by using straightforward explanations of often complex ideas.
Peter J. Fawcett, University of New Mexico

Archer has perfectly pitched answers to the most basic questions about global warming while providing a sound basis for understanding the complex issues frequently misrepresented by global warming skeptics. With a breezy, conversational style, he . . . provides a complete picture of climate change.
—Publishers Weekly

[An] enjoyable and fast-paced treatise. . . . Archer leads the reader to a simple yet accurate picture of climate changes, ranging from geological time scales to current warming, ice ages and prospects for the future.
—Susan Solomon, Nature

Dire Predictions: Understanding Global Warming Michael Mann and Lee Kump, (2008).

Publisher’s description:

The Intergovernmental Panel on Climate Change (IPCC) has been issuing the essential facts and figures on climate change for nearly two decades. But the hundreds of pages of scientific evidence quoted for accuracy by the media and scientists alike, remain inscrutable to the general public who may still question the validity of climate change.

Esteemed climate scientists Michael E. Mann and Lee R. Kump, have partnered with DK Publishing to present Dire Predictions–an important book in this time of global need. Dire Predictions presents the information documented by the IPCC in an illustrated, visually-stunning, and undeniably powerful way to the lay reader. The scientific findings that provide validity to the implications of climate change are presented in clear-cut graphic elements, striking images, and understandable analogies.

Readers will be able to understand the IPCC reports’ key concepts such as scientific uncertainty. They will also learn how to build a climate model and use it to predict future climates. Geoforensics is presented as a way to learn from the past by piecing together clues from prior climates.

Independent reviews:

Here’s a powerful, straight-forward guide to how scientists, economists, and engineers really understand the problem of global warming. It makes 20 years of research and consensus-building completely accessible to anyone who cares to know the truth–and to do something about it.
Bill McKibben, author of “The End of Nature”

With its eye-grabbing graphics and reader-friendly prose, “Dire Predictions” walks us through the findings of the world’s leading climate scientists – and places the ultimately responsibility for the human future directly at our feet.
Ross Gelbspan, author of “The Heat Is On” and “Boiling Point”

Dire Predictions is a must read for anyone who wants the straight facts on global warming. It cuts to the heart of the massive 2007 IPCC report, presenting major scientific findings in easy to understand language and graphics. Written by two of the scientific community’s most thoughtful researchers, Dire Predictions’ unbiased message about global warming arrives at a time when people need it most!
Dr. Heidi Cullen, Climate Expert at “The Weather Channel”


 Wie bedroht sind die Ozeane?, Stefan Rahmstorf and K. Richardson, (Fischer 2007, in German, English version published 2008)

Publisher’s description:

Die Meere sind eine Grundlage unseres Lebens — sie regulieren unser Klima und sind ein wichtiger Nahrungslieferant. Doch wir zerstören sie durch globale Erwärmung, Überfischung und Verschmutzung. Das wird verheerende Folgen haben, wenn wir nicht rasch umdenken und handeln. Dieser Band zeigt Ansätze auf, wie wir unsere ozeanischen Ökosysteme wirkungsvoll schützen können.

Global warming: Understanding the Forecast, David Archer (Wiley-Blackwell, 2006).

Publisher’s description:

Global Warming: Understanding the Forecast is a comprehensive introduction to all aspects of global warming. Written in an accessible way, this important book examines the processes of climate change and climate stability, from the distant past to the distant future. Examining the greenhouse effect, the carbon cycle, and what the future may hold for global climate, this text draws from a wide range of disciplines, and not only summarizes scientific evidence, but also economic and policy issues, related to global warming. A companion website provides access to interactive computer models of the physics and chemistry behind the global warming forecast, which can be used to support suggested student projects included at the end of each chapter. Global Warming: Understanding the Forecast provides an essential introduction to this vital issue for both students and general readers, with or without a science background.

Independent reviews:

Rigorous but rewarding, David Archer’s book takes us through the science of global warming so that we can more effectively assess where the world may be heading.
Andrew S. Goudie, University of Oxford

David Archer’s book is an accessible, entertaining, but detailed account of how scientists are trying to predict future climate change. It is an excellent book and should be the first port of call for anyone wanting to delve deeper into exactly what goes into those global warming forecasts.
Mark Maslin, University College London, author of Global Warming: A Very Short Introduction

This is a wonderful book. Between the covers of a surprisingly slim paperback, David Archer has distilled nearly everything a concerned undergraduate student could wish to know about the workings of the climate system…overall, this book perfectly hits its target audience.
Keith Alverson, Intergovernmental Oceanographic Commission of UNESCO, Environmental Conservation

Solar Activity and Earth’s Climate, Rasmus Benestad, (Praxis-Springer, 2006, 2nd Edition, originally published 2002)

Publisher’s description:

The main purpose of this book is to introduce the reader to the subject of solar activity and the connection with Earth’s climate. It commences with a brief review of the historical progress on the understanding of the solar-terrestrial connection and moves on to an objective scrutiny of the various hypothesis. The text focuses on how knowledge about the solar cycle and Earth’s climate is obtained. It includes discussion of observations, methods and the physics involved, with the necessary statistics and analysis also provided, including an examination of empirical relations between sunspots and the Earth’s climate. The author reviews plausible physical mechanisms involved in any links between the solar cycle and the Earth’s climate, emphasizing the use of established scientific methods for testing hypothesized relationships.

Der Klimawandel Diagnose, Prognose, Therapie, S. Rahmstorf and H. J. Schellnhuber (2006) (in German, Korean, Vietnamese; Arabic version forthcoming)

Independent reviews:

“In dem Buch “Klimawandel” in der Reihe “Wissen” des C.H. Beck Verlages melden sich zwei ausgewiesene Fachleute zu Wort: Hans-Joachim Schellnhuber ist Gründer und Direktor des Potsdam-Instituts für Klimafolgenforschung und Professor für Theoretische Physik an der Universität Potsdam. Stefan Rahmstorf forscht am Potsdam-Institut für Klimafolgenforschung und ist Professor für Physik der Ozeane an der Universität Potsdam. Auf 144 Seiten geht es einmal quer durch das Fachgebiet, das die Autoren in fünf Abschnitte aufgeteilt haben: Die Klimageschichte der Erde; die derzeitige globale Erwärmung und ihre Ursachen, die Folgen des Klimawandels; die öffentliche Diskussion um den Klimawandel und schließlich die möglichen Lösungswege. Viele ihrer Aussagen und Analysen zum Klimawandel sind bekannt – doch man hat sie selten so kompakt, übersichtlich und kompetent auf so wenig Raum zusammengefasst gefunden.”
Susanne Billig, Deutschlandradio Kultur, 23. März 2006

“Stefan Rahmstorf und Hans-Joachim Schellnhuber haben ein Buch geschrieben, das einen hervorragenden Überblick über Erforschung, Folgen und Lösungsmöglichkeiten des Klimaproblems gibt.”
RBB-Inforadio, 8. April 2006

Paleoclimatology: Reconstructing Climates of the Quaternary, Ray Bradley, (Academic Press, 2nd edition, 2005, originally published in 1999).

Publisher’s description:

Raymond S. Bradley provides his readers with a comprehensive and up-to-date review of all of the important methods used in paleoclimatic reconstruction, dating and paleoclimate modeling. Two comprehensive chapters on dating methods provide the foundation for all paleoclimatic studies and are followed by up-to-date coverage of ice core research, continental geological and biological records, pollen analysis, radiocarbon dating, tree rings and historical records. New methods using alkenones in marine sediments and coral studies are also described. Paleoclimatology, Second Edition, is an essential textbook for advanced undergraduate and postgraduate students studying climatology, paleoclimatology and paleoceanography worldwide, as well as a valuable reference for lecturers and researchers, appealing to archaeologists and scientists interested in environmental change.

Independent Reviews:

Paleoclimatology is a definite “must-have” for anyone working in climate studies and highly recommended for anyone seriously interested in our climate.
William R. Green, The Leading Edge

This thorough, well referenced text will prove to be indispensable to anyone involved in the study of past and current climate change and modeling.
Southeastern Naturalist

The Forecast in the Streets

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The physical impacts of the global warming forecast can be bracketed with some degree of statistical confidence. Biological effects are more difficult to gauge, except in special cases such as the likely demise of polar bears that would result from the demise of Arctic sea ice. The societal effects, however, are nearly uncharted territory, at least to me. Perhaps the topic of global warming suffers from the same sort of cultural divide as university faculties, between the techies and the touchies; that is the sciences and the humanities. A new report (pdf) called The Age of Consequences, just released by the Center for Strategic and International Studies and the Center for a New American Security, tries to bring the social sciences, in particular history, geography, and political science, into the forecast of climate change in the coming century. It makes for fascinating if frightening reading. [Read more…] about The Forecast in the Streets