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The Truth is not an option – part 1

Part 1. The Truth is not an option (it’s mandatory)

By Jeffrey S. Kargel

Disclaimer: The following 5-part series represents my own opinions and responsibility. Quotations are likewise not necessarily my opinions, but are of those quoted. –JSK

“An error does not become truth by reason of multiplied propagation, 
nor does truth become error because nobody sees it.”

–Mahatma Gandhi, Young India, A Weekly Journal, 26 Feb. 1925.

On September 15, 2011, midnight London local time, the publisher HarperCollins (HC) released a marketing statement about their newly published 13th Edition of the Times Comprehensive Atlas of the World (henceforth, the Atlas). The company marketed their renowned atlas via a press statement claiming an alarmingly high rate of loss of ice cover in Greenland1; one-seventh of the microcontinent’s permanent glacial ice cover had melted, thus “turning Greenland green,” just in the 12-year interval since their previous Greenland mapping. HC had announced the most dramatic consequence of climate change yet documented; or so they thought. Unfortunately for HC’s book sales, but welcome news to everybody else who may have believed the news, the story was a grotesque (and accidental) exaggeration of a real retreat occurring roughly a factor of a hundred more slowly2

It was a big mistake, but we all falter and sometimes fail. HarperCollins has not only apologized (albeit awkwardly), but took immense measures to rectify their mistake3-5. For HarperCollins, surely the motive was to support their claims regarding the quality and time-vaunted credentials of their atlas6. Why then is this still a story and a vital lesson to heed and to be committed to full record? It is not for the debt of the mistake maker, but for the debt of those who would repeat the accidental mistake of exaggeration of climate change or its mirror opposite of trivialization of climate change.

 

Earth is in the midst of what is widely regarded by physical and biological scientists as a dramatic planet-wide climate change, much of it caused by humans. Climate change is not a matter of contention among those who investigate it for a living. However, what scientists deliberate on, probe and question, are all the details: the mechanisms whereby different parts of the climate system interact, the scientific uncertainties stemming from insufficient observational constraints and incomplete understanding of the system as it works in totality. Though we’ll never know the full impact of today’s climate changes in the lifetimes of anybody living today, it is already clear that the climate changes and other attendant human-caused impacts are a geologic epoch-making event for planet Earth.  It is a disservice—very wrong-headed and destructive to our national and global well-being– to minimize the uncertainties or to use them to portray climate change as a non-event.  Because the Greenland Atlas mistake (clearly accidental) bears on the bigger issues, I would like to explain as clearly as I can why glaciologists and other global change scientists must get out of our chairs, away from our computers, and out of our crampons and into public discourse more than ever before.  People are confused, partly because of well-publicized mistakes and substantially because there are special interests out there who want people to be confused. 

From a deep-time geologic perspective, Earth has been through far worse, and better.  Ice cores from the longest glacial archives—drilled from Antarctic and Greenland ice sheets—as well as marine sediment cores, cave deposits, and other young geological deposits are clear about the large magnitudes of climatic shifts in the past hundreds of thousands of years.  Other geological materials point to even more extreme events, ranging from global glaciations to global hothouses, and from globally anoxic to extreme oxidizing conditions and many other global environmental changes; by comparison, today’s climatic shifts can seem pretty minor. Change is always tough, but it’s what made humanity.  So one wonders what may come next, after humanity perhaps.

Throughout geologic time, with every epochal climatic shift or other dramatic Earth change event, there have been many winners and losers.  The fossil record makes that clear. James Kirchner and Anne Weil7 first documented and analyzed the ripple effects of initial mass extinctions in the fossil record; these events commonly propagate for several million years with further extinctions at the family level and even higher biological groupings.  During these episodes, other biological families increase their individual numbers, and survivors of mass extinctions adaptively radiate to renew or even expand biological diversity after 10-20 million years following an initial devastating mass extinction event.  Nobody can predict the future with full reliability, but it would seem likely that we are at the start of a similar cycle, whether it is what Leakey and Lewin8 termed a major “Sixth Extinction,” or a lesser event.

There is nothing yet in the biological or climatic record of Earth that yet suggests the Holocene Age of Humanity as anything like the worst of the mass extinction episodes of the geological past.  The end of the Ice Age around the Pleistocene/Holocene boundary hit Earth’s global mammal diversity very hard, and the past century has devastated insect biodiversity. However, declaration of The Sixth Extinction8 is not yet warranted by what has so far elapsed with familial diversity during the Holocene, though it very well may have been initiated.  This chapter of Earth history is not done; no matter what humanity does to put on the brakes to changes we have started, the worst is probably yet to come both in terms of climate change and especially its consequences.

On the more human scale, there have been winners and losers caused by the more modest climatic shifts that have occurred during the ten millennia of Civilization. With every period of climatic stability or every epoch of tumult, biology, including human biology, adapts to the changes or takes advantage of the stability; or many species get wiped out.  For humans, climate change heralds the making of new history as it causes the ruin of the losers and blesses the new winners. Through struggle and death, survival, and adaptation to and exploitation of shifting climatic conditions, civilization came to be what it is.

Natural phenomena have caused climatic shifts in Earth’s geologic past that were far greater than what has elapsed so far in the past century of mainly man-made climate change.   Plenty remains unknown about our climate system. Things may be much worse than IPCC’s baseline models, with the global warming now underway heralding a new hothouse Earth; or things might not quite as bad as the likeliest baseline models.  The extremes of modeled possibilities are inherently unlikely, but it is absolutely a sure bet that climate change during the remainder of the 21st century will be greater than it was in the past century. This is because the greenhouse gas emissions are accelerating, and because several components of the Earth system involve lagging responses, such as melting of ice sheets and warming of the upper levels of the oceans, both of which cause global climate to warm up decades and centuries and even millennia after the initial triggers.

Most future-climate modeling focuses on the 21st century and doubling of CO2 levels from where they were a century ago; already, carbon dioxide levels have risen far above the range of natural fluctuations that were a key part of the glacial-interglacial cycles of the past 2.5 million years; this century, even in an optimistic scenario, greenhouse gases will reach levels likely not seen in the past 25 million years9,10.  This greenhouse gas is on a politically and economically driven course for doubling before 2100, and then it continues from there (assuming our global economy does not implode).  The present climatic upheaval will have immense consequences for the physical Earth—for example, melting of Greenland’s ice and some of Antarctica’s and radical shifts of the ocean currents controlled by melting ice; these changes will require several millennia to unfold completely.  Those physical impacts, in turn, will cascade across Earth. There will be a permanent legacy in global biota of climate changes already in progress now.   

For both the physical and biological Earth, our actions may be triggering a cyclic instability, finally undoing the Holocene’s comparative stability; or global warming may end up being a blip on the record, with climate quickly (after several millennia) restabilizing after the age of fossil fuels gives way to something more sensible and sustainable.

None of this is intended to frighten, but hopefully it will help some people listen to what modern science is very clear about—our environment is changing profoundly due to human influences. Not all the unfolding and impending environmental changes are bad or destructive, though in sum they are disruptive and difficult for humans to deal with.  I am not of the view that humans are necessarily destroying the Earth and pressing toward an uncontrollable implosion of the climate system and ecosystem; neither am I convinced that we are not doing so.  It is evident to me that there is a lot that we don’t know, and that there is immense potential that we are pushing the Earth’s climate system to a point where further changes will be so drastic and rapid that civilization might fare poorly.  A look at atmospheric greenhouse gas levels—clearly being driven sharply upward by human activities—shows that they are pushing into realms that have occurred in the geologic past but not for tens of millions of years.   The best of the atmospheric compositional records is from glacial ice cores going back 800,000 years; those superb records make clear that even the glacial/interglacial climate cycle—even during the warmest of the interglacials– did not involve CO2 levels nearly as high11 as what industrial activity has driven this gas concentration already. 

The atmospheric record is not so perfectly preserved during times dating from before the oldest glacial ice cores, but a wide variety of evidence has produced an atmosphere model going back hundreds of millions of years. Some periods had huge CO2 abundances, many times the current levels.  Whereas much-higher-than-contemporary greenhouse gas concentrations were necessary to counter effects of lower solar brightness (less solar heating) and prevent or reduce global ice ages during the earlier periods, the sun’s steadily increasing brightness has been a trivial factor in the more recent period of the Age of Mammals (the Cenozoic), when CO2 abundances have tracked global temperatures very closely.  A look at the fossil record during times of the highest (commonly highly fluctuating) atmospheric CO2 contents in the last 100 million years (since the last period of dinosaurs in the Cretaceous Period) indicates overall warm conditions—what geologists and climatologists call a hothouse—during the most extreme of those episodes.  Global temperatures were at times 8-14° F warmer than currently, and regionally even warmer than that.

It was not sunspots or lack of them, it was not comet impacts, or the Earth’s orbit or wobbling spin that caused those periods and climatic oscillations of that magnitude between hot and cold climates.  These natural phenomena definitely exert important controls on Earth’s climate and are a major part of natural Earth history, but alone these astronomical (“exogenic”) phenomena do not push climate to such extremes without the agency of greenhouse gases also acting.  Extreme climatic events were driven by fluctuations of greenhouse gases controlled by natural phenomena, including shifting continents and mountain building and erosional wearing down, and changing mantle circulation and midocean seafloor volcanism and plate spreading. Those slow geologic (“endogenic”) processes set the stage and activated the sources and sinks of atmospheric greenhouse gases; the gases pushed Earth’s climate to those warm extremes of the hothouse, and also to extreme cold and global glaciations. 

Some climate change obfuscators will point to the underlying geological processes that have driven the big picture of climate variations across hundreds of millions of years; indeed, that’s true12, but fundamentally—from first-principles physics—even for the geologically induced climate variations, it was disturbance of the Earth’s balance of heat and solar radiation coming through the atmosphere—the atmosphere here being key– due to sharp fluctuations in greenhouse gases that caused those extreme climate fluctuations.  The more extreme fluctuations involving hothouse climates (and their opposite, snowball Earth conditions, which last occurred over 600 million years ago) were two to three times more severe that the more recent climate variation between full glacial and full interglacial (e.g., Ice Age maximum cold period 18,000 years ago to present).  To blame plate tectonics does not escape the direct connection between climate and greenhouse gases, because the geologic processes of mountain building, rock metamorphism, volcanism, and rock weathering and sedimentation are what releases from and re-absorbs CO2 back into the Earth; while the CO2 is in gas form, it heats the Earth by trapping sunlight’s energy.  Because those processes relied on plate tectonics and other slow geological changes, they took tens of millions of years to unfold.   Ocean physics also are key in Earth’s climate—just consider the El Niño/La Niña cycle.  But the oceans respond to the radiative balance mediated by the atmosphere.  Many components of the Earth climate system make it devilishly difficult to model, but we do have the empirical evidence of past climate fluctuations forced by greenhouse gases—we can rely on it.

It doesn’t matter what it is that releases CO2 into gas form in the atmosphere; release it on a large scale, for any reason—geological, glaciological, or human caused—and climate will warm.  It does it on Venus, on Mars, and on Earth and would do it on any planet in the Universe. There will always be other things that cool climate, warm it, dry it, or moisten it, and some of those are related to greenhouse gases, and some are not.  But the biggie by far for climate change on Earth is CO2 abundance.  This is fact, not politics; it’s reality, not wishes; it’s physics, not metaphysics. 

Some life flourished during those hothouse times of the distant past.  Indeed, high carbon dioxide and warm temperatures yielded an abundance of life and high biological productivity.  The fossil record states as much, as do major hydrocarbon deposits (oil, shale oil, coal, peat, and conventional natural gas) owing their origins to life thriving (and dying) during the Cretaceous hothouse golden age of dinosaurs and coal-making forests, and during some of the early Cenozoic times of rapidly diversifying mammals and productive, shallow seas.  So to state that the IPCC errs on the side of a conservative assessment of our CO2 emissions and climate trajectories, and that hothouse levels of CO2 may be in store for us the way things are going, is not entirely a doomsday story; some genera and families, orders and classes of organisms may indeed be doomed and others blessed.  It would be the Sixth Extinction, but that may herald something like a Triassic Park Earth, eventually with a flourishing of life such as that which developed after the Permian mass extinction.  Could humans be a part of Earth’s surviving biota in that case?  At the milder end of possibilities, if the IPCC is closer to being right, maybe civilization can prosper and we just deal with Savannah, Georgia and the Mekong Delta being inundated and Tuvalu disappearing under the waves. (Please pardon my understatements.)

It is not clear whether a full hothouse Earth or simply the warmest-ever interglacial is in store for Earth, with present trajectories on greenhouse gases; those two pretty much bracket the possibilities.  The IPCC climate scenarios are biased (scientifically biased; I don’t mean prejudicially) toward the milder of the possibilities.  Either extreme of climate sensitivities will be highly consequential for humans (already is consequential, as the news makes clear), and either one will stress global civilization potentially to a breaking point.  On the other hand, I would not dismiss the possibility that clever and wise humans would be able to take our present mistakes, deal with the climate consequences, and develop the means to thrive even through the worst scenarios.  I simply don’t know what we are capable doing, either for our betterment or our demise; whereas I do know that we are clever, I do not know whether we, collectively, are wise; evidence seems to indicate that we—the winners of ruthless competition– are not a wise species, but so far merely clever, physically robust, and lucky.

One can view those hothouse times of elevated CO2 as good times—good for those species where a hothouse Earth is helpful, say for example, if you’re a giant dragonfly or an aquatic reptile or a central Amazon basin floodplain forest tree.  For those now living who are adapted to colder conditions, sharply elevating atmospheric CO2 would not seem to bear good news. 

That brings up the matter of humans; all human and closely related species evolved over the last couple million years under conditions of alternating glacials and interglacials; we are a product of ice ages that stressed us to the limit of survival, and interglacials that allowed us to spread and multiply. Humans were the best of all in adapting quickly to rapidly changing environments.   Whereas civilization arose during the present interglacial, humans (and notably, Caucasians), are not adapted to hothouse conditions. To be sure, there will be winners as well as losers as we move closer to hothouse conditions.  Warming may help maple sugar producers in Quebec, mango farmers in Florida, intercontinental shippers interested in moving goods through the Arctic’s long-sought Northwest Passage, and mosquitoes and cockroaches across most of Earth’s land surface. But overall, Earth tending toward a hothouse could not be helpful for a species, such as ourselves, whose physiology and ecology is adapted to glacials and standard interglacials. 

However, climatic fluctuations imposed the stresses and forced on our species the global evolutionary game of “Survivor.” The wild Pleistocene climate ride is what drove human evolution.  So maybe we can make it through this. So long as stresses of a rapid transition (a mere five-generations long) to a hothouse do not cause the implosion of society and civilization, technology might make up for what adaptive evolution has not produced in humans.  The trick is avoiding that implosion.  Unfortunately, if we look at the last century, the political adaptation to technology itself seems to be the greatest threat to civilization’s survival.  World history of the 20th and 21st centuries do not lend much encouragement about our global ability to handle yet more stress.    

Now get ready for some optimism. The fossil fuels industry in the U.S. currently likes to run TV ads that consider carbon dioxide to be an essential nutrient that can make a greener environment: more vegetables and happy family times for all; those ads miss quite a few points, but they also make a valid one that plant growth rates are increased—all other things equal—by increased carbon dioxide abundances (except for the many places, such as my state of Arizona and much of the U.S., where it is invalidated by regionally drying climate that goes with warming). But far beyond all the spin each way—doomsday or a Garden of Eden– life on Earth is almost as insistent as plate tectonics and mountain building. Life is mutable, adaptable, and almost unstoppable, taken a phylum at a time.  Survival of biological species, genera, and families—surely including human beings—is sensitively dependent on climate, and many do not make the transitions of climate changes that are even less than what now is unfolding. But biological revolutions follow climatic upheavals and initial biological extinctions, with new adaptations and new life arising where old life is wiped away.

And so how can I say that man-made climate change and disappearing glaciers and ice sheets are bad things? I can feel that it is bad, and I can worry that danger lurks, but I cannot know that the future is dismal.  Humans are highly adaptable as well, though it is not clear that civilization is. Taking the long view, the future will arrive and allow prosperous times either for humans or for something else that may replace us at the top of the vertebrate pecking order.  And yet we are human and most of us revel in what civilization has brought and what it tries to promise for the future; for our own benefit, and that of our grandchildren, we probably ought to be careful with planetary engineering.  Here is my understated seriousness, in case it is missed.

And so from a perspective of humanity and civilization, I have felt obligated to point out some likely severe consequences of following our present path of planetary engineering.  I don’t know the full scope of the consequences.  Nobody can know. Humans could well become extinct or sent back to the Stone Age; or we might find a way, with the power of technology, to thrive through it all. Aside from the uncertainties pertaining to the climate models and consequences, the biggest uncertainty of all is how far society will be misled and how obstinate special interests on every side will be.  Narrow political interests and their miseducation/misinformation engines are now largely determining our current fast-track trajectory of global greenhouse gas emissions.  Narrow interests on the other side, who would seek to misinform in the other direction in terms of exaggerations, can and are delaying positive recognition of how things really are; they are, presumably unintentionally, helping to defeat reconciliation of well-meaning parties on all sides of the logical components of the debate.

On the other hand, is humanity simply fated to self-exterminate, one way or another?  Does it matter?  I shall leave as a philosophical postulate that civilization is fundamentally important.  So then we should be looking to define our most severe problems as accurately as we can, and to find the most effective solutions.  This logic is not very controversial and should have widespread adherence among the public and governing officials around the world.  Misinformation (whether encompassing exaggeration or trivialization of climate issues) is surely an impediment to progress. We cannot let anybody off the hook.  The fact is, we are all on the hook.

The ONLY way that a widely shared goal of human prosperity will be achieved—a foremost requirement– is by widespread recognition of the truth about climate change, and then wise political and economic responses to the knowledge.  Exaggeration or trivialization of severe problems cannot produce an efficient or effective solution.  Instead, global policy has been commandeered by political forces that are explicitly planning for the future based on a faulty assumption that climate is not shifting or has slight variations confined within the range of recent human experience. This is a demonstrably faulty premise, yet trillions of dollars per year are being spent based on the false premise to do more in the 21st century that we did in the 19th and 20th centuries, as if more of a path that worked for a time is what will take us to somewhere good in the future.  It will not. It is a dead end for civilization. We certainly need fossil fuels to get us from where we are to where we need to be, but we must diverge from our current path and do so quickly.

Needless to say, our world’s leaders’ premise that exponentially rising emission of greenhouse gases are irrelevant to climate and economics yields economic inefficiencies and foreclosed opportunities for sustainable growth and prosperity.  On the other hand, and equally haunting if we were to follow it, an unrealistic, exaggerated, and panic-inciting view of climate change cannot result in an efficient path forward. In fact, the biggest problem with exaggeration is that it yields demonstrably false statements that are exploited by the climate change trivializers, who then push policy their faulty way.

A general consensus and plainly understandable approximation to truth as pertains to climate change is, in its broad outlines, not that difficult to achieve (it has been achieved among scientists), if people of influence in non-climatology sectors would simply agree that they will not fear and shun the truth or obfuscate it, but use the information wisely.    There can be legitimate debate about complicated things like nature and glaciers, the weather and climate, the economy and energy supplies. But maybe acknowledging the truth or some resemblance of it is  too much to ask of our politicians. 

It is a mark of maturity and a flag of readiness to make progress in life to acknowledge reality and then to deal with it. Our parents spent a generation teaching us this, and so we do likewise with our children.  So far, maturity is in short supply among most world leaders and those who influence society. The hope is that the law of supply an d demand applied to responsible leadership would drive up the value and votes for responsible leaders.  Regardless of politics, playing with the truth is not something scientists, in general, can or will tolerate. It’s not that we are somehow better than politicians, but it is imbued in scientific approaches to observation and critical thinking that ideas that are gross departures from reality are discovered, exposed, and replaced with other ideas that tend towards being less errant.  With science, it’s ten steps forward and three or four back, but the trendline is progress of knowledge and understanding. 

Honest mistakes are easier to understand from a human perspective (we all make them) compared to falsehoods generated by deliberate obfuscation and planted misinformation, but depending on the nature of the mistake it might not always be something to gloss over.  Hence, in this blog series, I come down hard on an honest mistake. All the more so, mis-informers on the other side should feel a need to stick to the facts.  The science community simply won’t take it anymore. 

It happens that the Atlas fiasco that spurred this blog series pertains to Greenland’s ice.  But the lessons learned go far and need to be spelled out. I’m not writing in a moralizing call to truth, but from a much more pragmatic perspective. If we, as a society, obscure reality, there is no possibility of finding the most economically efficient and environmentally sound and healthy solution to some of the most vexing problems we face.  To be designing a 21st century economy on false premises will hit the world’s billions in the pocketbook and will shift the balance of power of nations; given global and national policies designed by misinformation, that is as optimistic as I can be; from there, the pessimism cascades to further possibilities where not even the greedy have any winners. 

Tomorrow and the next days I will document the discovery of the HarperCollins Atlas mistake and the scientific community’s response to it.

References

1. HarperCollins issued a marketing statement heralding the publication of their new atlas, stating, “For the first time, the new edition of The Times Comprehensive Atlas of the World, published on 15 September, has had to erase 15% of Greenland’s once permanent ice cover – turning an area the size of the United Kingdom and Ireland ‘green’ and icefree… Cartographers of the atlas have sourced the latest evidence and referred to detailed maps and records to confirm that in the last 12 years, 15% of the permanent ice cover (around 300,000 sq km) of Greenland, the world’s largest island, has melted away.

     The original HarperCollins statement, in reference to the supposed 15% loss of ice cover in Greenland, also wrote, “This is concrete evidence of how climate change is altering the face of the planet forever – and doing so at an alarming and accelerating rate.   … Developments are being watched closely. Modelling predicts that Greenland could reach a tipping point in about 30 years, and after that little would prevent its ice cap from melting completely.”

2. Kargel, J. S. A. P. Ahlstrøm, R. B. Alley, J. L. Bamber, T. J. Benham, J. E. Box, C. Chen, P. Christoffersen, M. Citterio, J. G. Cogley, H. Jiskoot, G. J. Leonard, P. Morin, T. Scambos, T. Sheldon, and I. Willis, 2011, Brief Communication: Greenland's shrinking ice cover: ″fast times″ but not that fast, The Cryosphere Discuss., 5, 3207-3219 (accepted, in press for The Cryosphere).

3. HarperCollins, through spokesperson Sheena Barclay (from a subsidiary, Collins Geo), during the week following the mistake, made this amended public statement: “Since the publication of the Times Comprehensive Atlas 13th edition on 15th September 2011, controversy has raged about the depiction of Greenland in the Atlas.  The editorial team at Collins Geo have apologised for an incorrect claim in the media material accompanying the launch…. On reflection and in discussion with the scientific community, the current map does not make the explanation of this topic as clear as it should be.”

4. HarperCollins, also through Sheena Barclay, then further explained,“We are now urgently reviewing the depiction of ice in the Atlas against all the current research and data available, and will work with the scientific community to produce a map of Greenland which reflects all the latest data.   We will then create an insert for the current atlas showing this map and also give an explanation of the situation and how we have mapped it.  Any material generated as a result of this activity will also be made available online …

5. For weeks after their blunder, HarperCollins signaled that they would correct the maps.

http://www.realclimate.org/index.php/archives/2011/11/times-atlas-map-of-greenland-to-be-corrected/

   On January 2012, upon re-releasing their Atlas with the Greenland updates in their double-sided insert, stated prominently on their website, “After publication of the 13th edition of The Times Comprehensive Atlas of the World it became apparent that we had not represented the permanent ice cover in Greenland fully and clearly. In failing to do that, this section of the map did not meet the usual high standards of accuracy and reliability that The Times Atlas of the World strives to uphold. To correct this we decided to produce a new, more detailed map using the latest information available.

http://www.timesatlas.com/Pages/default.aspx

http://www.timesatlas.com/News/Pages/Home.aspx?BlogID=63

6. The HarperCollins bills their Atlas as “The Greatest Book on Earth,” and “The world’s most prestigious and authoritative atlas.”

7. Kirchner, J.W. and A. Weil, 2000, Delayed biological recovery from extinctions throughout the fossil record, Nature 404, 177-180.

8. Leakey, R., and R. Lewin, 1996, The Sixth Extinction, Doubleday.

9. Royer, D., 2006, CO2-forced climate thresholds during the Phanerozoic, Geochimica et Cosmochimica Acta 70, 5665–5675.

10. Beerling, D. and D. Royer, 2011, Convergent Cenozoic CO2 history, Nature Geoscience 4, 418-420.

11. Lüthi, D. and 10 others, 2008, High-resolution carbon dioxide concentration record 650,000–800,000 years before present, Nature 453, 379-382.

12. Veizer, J., D. and 14 others, 1999, 87Sr, d13C, and d18O evolution of Phanerozoic seawater, Chemical Geology 161 (1-3), 59–88.

 

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