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James Hansen on Climate Tipping Points and Political Leadership

By James Hansen

Jul 15, 2009

The obvious conclusion is that the only practical way to avoid climate catastrophe is to terminate emissions from the largest fossil fuel source: coal, the dirtiest of the fossil fuels. If coal emissions are phased out between 2010 and 2030, global fossil fuel emissions would begin to fall rapidly as shown in the chart below.

The rate of emissions (shown in billions of tons of carbon on the left and in percent of 2008 emissions on the right) depends upon how much oil and gas is used. The (red) curve showing larger emissions is based on the assumption that the larger reserve estimates of EIA are valid and all of the CO2 is emitted to the atmosphere. These emission scenarios have been converted to atmospheric CO2 amounts using a simplified version of the Bern carbon cycle model.

The next chart shows that atmospheric CO2 would peak at only ~400 ppm in ~2025, if the IPCC oil and gas reserves are accurate and if coal emissions are phased out uniformly over the period 2010-2030.

If, however, the EIA oil and gas reserves are accurate (and if coal emissions are phased out), atmospheric CO2 will peak early in the second half of this century and atmospheric CO2 will be about 30 ppm higher than with the IPCC reserve estimates.

The EIA reserve estimates may be realistic if we choose to go after every last drop of oil by drilling off-shore, on public lands, in the Arctic National Wildlife Reserve, and in the deepest oceans, for example. With these larger reserves exploited, future generations, including our grandchildren, likely will be forced to seek ways to extract that extra 30 ppm of CO2 from the atmosphere. In the referenced paper we discuss the costs of air capture and disposal of CO2, estimating a cost of about $200 per ton of carbon. Thus the cost of removing 30 ppm would be about $12 trillion dollars, a burden that would be passed to our descendants.

The primary implication, however, concerns coal. The reason that CO2 peaks at only 400-425 ppm in these scenarios is the assumption that coal emissions will be phased out linearly between 2010 and 2030. Such a scenario is technically possible, but only with policies that lead to availability of appropriate alternative technologies and incentives for using them.

We must move beyond fossil fuels at some point. Why not do it sooner, for the benefit of our children?

Political Leadership

Political meetings may produce lofty goals for reduced carbon dioxide emissions by some future date. But these are of practically no significance if the goals and the actions of the nations are inconsistent with geophysical constraints.

For example, I spoke with a German Minister. We found that we were in good agreement with the startling conclusion that we are already moving into dangerous levels of atmospheric CO2. Yet Germany plans to build more coal-fired power plants. His rationalization was that they could “tighten the carbon cap” on cap and trade.

I pointed out that, if coal emissions continued, that cap would somehow have to force Russia to leave its oil in the ground. I asked how he would convince Russia to do that.

He had no answer.

The overwhelming practical requirement, for the sake of future generations, humanity itself, and the other species on the planet, is phase-out of coal emissions over the next 20 years.

The correct fundamental approach is a rising price on carbon emissions, as needed to achieve these objectives. The Waxman-Markey bill fails the test in the same way as the German plans: it builds in approval of new coal-fired power plants. There is no need for these plants except to enrich utility and coal special interests – they are included only because the monstrous 1400-page absurdity was hatched in Washington after energetic insemination by special interests.

Global warming

As any person who relies upon the weather for a living knows, the climate is always changing.

I am tired of hearing all these statements from Hansen and the other "Global Warming" hoaxers declaring that they know best, when they are really only seeking funds for another study.

I have no problem handling a warm climate.

However, the thought of another ice age, which can happen realatively quickly, dismays me.

nise ..and good.thanks

nise ..and good.thanks

Hansen wants to overthrow democracy

i can't believe you're giving a venue to people like Dr Hansen who endorse books telling people to sabotage dams and power plants to bring about the end of "industrial civilization" and who praise communist dictatorships like China.

Don't you think that democracy is more important than climate change?

Yes Global warming is more

Yes Global warming is more important than democracy you fool 


I second Tom's comment.  Hansen recently oozed admiration for the Communist system in China where the ruling class could implement changes "very rapidly" (meaning by decree).  Recently we also saw a video from the entitled "No Pressure" in which people (including school children) who did not agree to reduce their personal carbon emmissions by 10% were obliterated when the eco-tyrrant urging change pressed a button after telling them they had a right to disagree.  We were also recently treated to a video from another environmental group, Forum for the Future, in which people were placed in tightly controlled cities and placed on no meat diets by the Global Food Council.  High school students were "assigned" career instead of choosing them, and dissidents were forced to live in a ghetto called "Cry Freedom".  It's high time people realize that objecting to maniacs such as Hansen who would love to see an authoritian state enforcing his views on the world is vastly different from saying we don't need to lower carbon emmissions.  If he were the exception among the climate alarmists that would be one thing.  But, rather, it seems to be a mindset among them. 

Fossil Interests & Selfishness VS. Education & Altruism

Tom & Seconded, 

I feel so very sad for the both of you and for the state of your minds.  If you would only look at the overwhelming science and the millions of people that will be displaced, killed, and left for dead because of your negligence.  We, the United States of America, have always been the biggest contributors in terms of greenhouse gases from industry, electricity, and transportation.  Yet, you will see in future years, that those who have contributed nothing will suffer the most.  22 of the 30 countries that will be most severely effected by climate change are in Africa.  Now, when it's time for us to sacrifice for the betterment of the human race, we've started to run scared.  We've lived large for so long - the least we can do is be pious and do our best to prevent pain and sadness for others.  Please, for the sake of your fellow humans - your brothers and sisters all over the world - don't be so narrow-minded.

It's very interesting and disheartening that you would refer to Dr. Hansen's scientific inferences as "his views," when climate change is one of the most heavily researched issues in the history of mankind.  I don't see anyone raising a fuss when scores of cholesterol-reducing medications are flying off of the shelves and billions are being invested in research to see how unhealthily Americans can live without dying.  Yet, when funding for generation-saving research like climate change comes along, people like you embarrass our nation - you embarrass human beings as a whole.  

Yes, the issue of climate change is diffuse and nebulous at times.  However, just because the solution isn't as easy as banning CFCs or popping a pill, it doesn't mean we should abandon all rationality and start calling world-renowned scientists "maniacs."  

Do you have children, or grandchildren?  I do.  I care deeply about their future and the lives of generations beyond that.  Please, if you aren't going to be part of the solution, keep your narrow-minded-loose-lipped-unsubstantiated-ridiculousness to yourself.  Read a book on climate science.  Educate yourselves.  Think before you speak.  Stop getting your information from YouTube and wake up to reality.  Changes are already being seen - how will you explain your apathy to your children and grandchildren?  



Mobil Keluarga Ideal Terbaik Indonesia

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Architecture 2030

I was wondering if anyone can offer their thoughts / opinions on Its campaigning for congress to amend "Section 241 of the Senate Energy Bill (S. 1462) to provide for building energy reduction target dates."

Professor Richard Lindzen: Carbon Dioxide irrelevant in climate

Google the following article in The Examiner

"Carbon Dioxide irrelevant in climate debate says MIT Scientist :"

"In a study sure to ruffle the feathers of the Global Warming cabal, Professor Richard Lindzen of MIT has published a paper which proves that IPCC models are overstating by 6 times, the relevance of CO2 in Earth’s Atmosphere. Dr. Lindzen has found that heat is radiated out in to space at a far higher rate than any modeling system to date can account for

Professor Richard Lindzen of MIT’s peer reviewed work states “we now know that the effect of CO2 on temperature is small, we know why it is small, and we know that it is having very little effect on the climate.”

"The global surface temperature record, which we update and publish
every month, has shown no statistically-significant “global warming”
for almost 15 years. Statistically-significant global cooling has now
persisted for very nearly eight years. Even a strong el Nino – expected
in the coming months – will be unlikely to reverse the cooling trend.

More significantly, the ARGO bathythermographs deployed
throughout the world’s oceans since 2003 show that the top 400
fathoms of the oceans, where it is agreed between all parties that at
least 80% of all heat caused by manmade “global warming” must
accumulate, have been cooling over the past six years. That now prolonged
ocean cooling is fatal to the “official” theory that “global
warming” will happen on anything other than a minute scale."

If for no other reason than this: the IPCC assumes that the concentration of CO2 in 2100 will be 836 ppmv (parts per million volume). However, current graphs based on real data show that CO2 concentrations will only be 570 ppmv in 2100, cutting the IPCC’s estimates in half right there.

Another nail in the coffin of Global Warming is the observed rate of temperature change from 1980, which is observed to be 1.5 degrees C per century. The IPCC modeling calls for a range of 2.4 to 5.3 degree increase per century, which is far above what is observed in real data collected between 1980 and 2009. The graph below clearly represents a far different reality as opposed to the predictions.

You do realize that the

You do realize that the quote in your comment isn't actually from the study, don't you? Or did you bother to read the study before repeating the blather of a business consultant?

You clearly didn't read the IPCC report either, since you misstate their numbers as well.

Here's a link to the Lindzen & Choi study, discussion of a follow up paper accepted by the same journal that points out serious errors in the Lindzen & Choi study, and Lindzen's own response noting the validity of that follow up paper:

climate change = scam?

So, I've started hearing about a bunch of e-mails and documents that were supposed to be secret between some "climate scientists" that were posted on the internet and now prove that global warming is a giant scam. Does anyone know what the deal is with this one?


The hacked emails were not "secret," they were private communications between colleagues, just like you email your friends. They talked about one another's health and where they'd been on vacation. If you read them, you'll learn more about the personal lives of the scientists who never intended for their personal lives to be made public than you will about climate science. I'm sure none of us would want that to happen to our private emails. There was no hoax. What you're hearing about is the complaints among these scientists about how industry supporters were harassing them to make sure they couldn't do their jobs. The only scam is the way industries hell bent on making money at everyone else's expense are trying to stop science.

They've been out for a while now

These emails have been out for a while now and present decent explanations of why global warming may be a hoax. Fear is a great asset to any government and those who want to monopolize on the fears of nations will do so. But over the years there has been a lot of very good explanations on why global warming is real. The thing is, what should we believe?

Surely you're missing the point?

You say... "Changes are beginning to appear, and there
is a potential for rapid changes with effects that would be irreversible – if we do not promptly slow fossil fuel emissions during the next few decades."... but surely when one looks at "greenhouse gas" emissions overall the fossil fuel element is relatively small in comparison to other factors? Does methane caused by farming of animals not make up more than 50% of the total greenhouse gas emissions now? Surely this should be tackled as a matter of urgency rather than focusing on one element which has long been pushed to the top of the political agenda to the detriment of other more important ones.

reproducing science

Speaking as a non-scientist, I did have the sense that, when a scientist comes out with results, what other scientists do is not to demand all the first one's data, but to try to reproduce the results in gathering data themselves. I do not see that Michael Mann and James Hansen need to turn over all of their rough work to others. Challengers need to stop nitpicking and try to best Mann's and Hansen's outcomes. Given that Mann and Hansen seemingly have high standing in the scientific community, challengers who are less known may be obliged to share their own rough work. That's life.
Deciding that Mann made his determinations on the basis of some tree cores and that that's not enough data, is not a sufficient refutation. It is just a matter of calling some one a liar without doing one's own due diligence. The skeptics do not really know what was Mann's data; they think they have figured out the whole of what it is, but I am not convinced. Doing the science themselves is due diligence.

"tens of meters"??? Give 'em

"tens of meters"???

Give 'em another month, they'll be screaming about "hundreds of meters". A month after that, it will be "several miles".

You'll see. Political interest does not deny itself.

Vitriol. I am not at all

Vitriol. I am not at all sure this is about large corporate entities buying professional bloggers so much as I am concerned this is about Single Variable Processors vis-a-vis Multiple Variable Processors. If we adopt the position that the prognosticated future climate change will occur due to the result of a single variable, we place ourselves most squarely into the midst of a signal to noise ratio polemic that literally cannot be detected. Consider for a moment that the IPCC's AR4 report has as its upper limit of AGW sourced temperature and sea level lifts in the range of 2C and slightly less than 2-feet, this is an "anomaly" of such magnitude that it pales in significance to the well documented 20 feet of sea level rise that just occurred in the Holocene Climate Optimum, and barely comes in in the 2-4C rise in global temps above present this event managed during the time when we had just learned how to distill metals out of rocks.

Just like the next hominid, I can easily be scared out of my wits by a singular threat. But you are going to have to do a whole lot better in fantasizing a threat than that which is egregiously overshadowed by the natural climate noise. Think about it. Just think about it for a moment, incorporate just one measly variable into your decision matrices. If during the Eemian, sea levels topped out 20 meters (60 feet) above present, out of three documented sea level highstands that did the same during that interglacial, and we have evidence of just a single one, so far, in the Holocene, a rational person would believe this won't, couldn't happen again. During MIS 11, 400k years ago, we topped out at 21.3 meters above present. I could go on and on.

The sad truth of it all is that 2.8 million years ago, humans suffered a paradigm shift. We discovered rocks. This single variable process of the stone age, massaged mathematically (one would hope) and intuitively as it was, took about a million years to graduate to the Acheulian tool period (hand axes or bi-face tools). It was only at the close of the Neolithic, during the Holocene Climate Optimum, that we made it to written language, not even 10,000 years ago (in fact less, homework assignment).

Reliable, dramatic and sholly unavoidable climate shifts happen far quicker than that, we divined in the past 20 years. Completely on their own. We are only now comprehending the multi-variate complexity of it all.

Pitiable as those SVPs of far lower braincase capacity were than we are today , they made it through somehow. Sometimes. Another variable worth devoting some cpu time to is just how astonishingly well the fourth cycle of eccentricity matches up with hominid evolution.

“An examination of the fossil record indicates that the key junctures in hominin evolution reported nowadays at 2.6, 1.8 and 1 Ma coincide with 400 kyr eccentricity maxima, which suggests that periods with enhanced speciation and extinction events coincided with periods of maximum climate variability on high moisture levels.”

state Trauth, et al (2009) in Quaternary Science Reviews. There is just nothing quite like having such a natural fly land in your climate change soup. As it turns out, climate change, periods of wet maximum climate variability, cook up the larger braincases. We went from 500-550cc braincases 2.8 mya to the average of about 2,500cc today in the most rapid encephalization of any mammal in the fossil record.

As we witness the shrillness and devotion to the single variable future, one cannot help but process all the other more certain variables into the vision that what we really need right now is just such a period. For, unfortunately, it seems to be the only thing that smartens old Homo up.

Sure, climate change is

Sure, climate change is natural.  The world's top climate scientists would agree with you!  The Milankovitch cycles are of course to blame (eccentricity, precession, and tilt).  These are basically just fancy ways of describing the earth's different orbital patterns.  Each of the 3 orbital patterns coincides with a certain number of years.  For example, eccentricity (large oval orbital) is based on a 100,000 year cycle.  This cycle alone, eccentricity, accounts for an ice age roughly every 100,000 years.  We're not headed for another natual ice age for tens of thousands of years.

However, what makes this current climate change UNIQUE is that fact that for the last 800,000 years CO2 hasn't gone above 300ppm.  We get this data from ice cores (Oxygen isotopes are proxies for temperature and we can also see CO2 levels in ancient air bubbles).  Then, we started burning fossil fuels at the beginning of the Industrial Revolution and CO2 started to rise dramatically.  We've gone from 280 to 387.  Remember, CO2 hadn't gone above 300 in 800,000 years - that is, not until humans came along and started burning fossil fuels.  This data in combination with temperature increase measurements makes climate change unequivocal. 

Please stop cherry-picking data and trying to fleece people's minds.  Yes, we will see natural climate change in the future - it's inevitable.  However, it's not going to happen for a very very long time.  In the interim, let's try to hone in on reality shall we?


Climate Models

There is little reason to believe the IPCC climate models. First, there are many weaknesses in the models. Chief among them are how water vapor and clouds are modeled. And these weaknesses are acknowledged by the modelers themselves. Further, these models cannot duplicate climate from the past, for example, entry into an ice age or how an ice age retreats. Why give credence to these models?


One hears more and more about professional blog-commenters being employed by the large climate change skeptical interests; the vast majority of comments on this page are both well-informed, and focus wholly on discrediting the author; they show zero concern for what is actually going on and what should be done, and I don't believe this is representative of the public's stance.

The politicisation of climate change science means that the general public CANNOT make an informed decision - which I find extremely distressing. However most of the commentators on this page are too confident in their skepticism. Just as atheists are fools for believing the exact contrary of the theists, these voices come across as egotistical, despicable, and no less extreme than Hansen.

The issue of climate change demands urgent action. Even if the humans and carbon dioxide are not the cause, we have to
-get more and better information
-reduce all kinds of pollution and natural resource consumption - (wouldn't our grandchildren value fossil fuels and patches of nature?)
-put the brakes on global population growth
-take steps to mitigate the effects of climate change


Far from being a professional blogger paid by big coal or whoever, my post below represents my personal view. I expressed this because I believe Mr Hansen is no longer a scientist, but is a political activist with an agenda. The warmists often complain that the sceptics all have vested interests, but any person employed in the climate change industry also has a vested interest in their career. And since most of the money available in this industry comes from government funded grants, it is in their interests to only apply for grants to research the politically accepted agenda of the day. And what more political organisation is there than the IPCC?? Check out the reason for their existence on their website.

Another attack by the warmists is that sceptics should publish peer reviewed papers if they want any respectability, but in the field of climate change, peer review seems to be a sham. Traditionally, peer review meant that you provided all the information necessary to enable a competent fellow scientist to replicate your work, & critique your methods. In climate change theory, this means they would have to hand over the original data they used, describe how they "adjusted" that data into a usable form, & provide the source code of their computer models. Do you know of any climate scientist who has done this?? Until people like Michael Mann & James Hansen do this, I will take anything they say with a lump of salt.

The CO2 levels have dropped???

In his letter to Japan's Prime Minister ahead of the G8 summit, Hansen remarks:
"My address tomorrow to the United Nations University G8 Symposium summarizes scientific data revealing that the safe level of atmospheric carbon dioxide (CO2) is no more than 350 ppm (parts per million), and is likely less than that. Implications for energy policy are profound, as atmospheric CO2 is already 385 ppm."

Now we hear him say he believes "it is still feasible to solve the global warming problem before we pass tipping points."

When did the CO2 levels drop?

Hansen is a not a well man

He reminds me of story of an ill fated earth scientist told to me in grad school. The geologist in question became so obsessed with the Rocky Mountain tectonics that he was firmly convinced that the Rockies were going to slide right over him and crush him. The scientist tragically ended up taking his own life.

I pity James Hansen and hope that someone intervenes on his behalf; much as I disagree with his ideas, I fear that his irrational obsession may end poorly.

I pity you for your ignorance

I pity you for your ignorance and closed mindedness 



To quote Dr. Lindzen:

Nor is the assumption that the earth’s climate reached a point of perfection in the middle of the twentieth century a sign of intelligence.


You say above that "Changes

You say above that "Changes are beginning to appear". Is one of these changes the fact that the earth is now getting colder? Did we 'tip' some time around the year 2000?

Dansgaard-Oeschger oscillations

We know with absolute certainty that these events happen, with evidence of D-O oscillations extending back some 680 million years. We do not know yet precisely what causes them.

I don't know what caused them either, but I'm pretty sure it wasn't the Internal Combustion engine.

Science of tipping points

Dr Hansen,

You say:

Our global climate is nearing tipping points.

What is the evidence for the existence of tipping points?

What science has revealed in the past few years is that the safe level of carbon dioxide in the long run is no more than 350 ppm.

What, please, is the evidence and reasoning for this?

tipping points that would guarantee disastrous irreversible climate change.

What evidence shows that climate change will be disastrous and irreversible?

As Arctic sea ice melts, the darker ocean absorbs more sunlight and speeds melting. As tundra melts, methane, a strong greenhouse gas, is released, causing more warming.

This can only happen during the summer, as in the sunless winter everything re-freezes. Within the summertime Arctic Circle, the sun is low in the sky and its light passes through extra layers of atmosphere, so that the energy received per square metre is reduced to about 1% of the tropical value. What are the calculations or observations that verify that this mechanism for melting ice is feasible?

Richard Treadgold,
Climate Conversation Group.

More Hansen hysteria

By now Mr. Hansen is so compromised as a scientist that he is irrelevant in that capacity. He is not longer a disinterested scientist but is now a full-fledged activist who, as a paid government employee, advocates for ever-expansive government to solve a problem he theorizes about.

Mr. Hansen and the rest of the global warming "science" industry have only legacy may be that they have irreversibly politicizes science. Who knows with any luck if Hansen and the rest of his cadre keep it up, 20 years from now the public may have the same esteem for science as they have for the US Congress.

James Hansen

James, I don't know how you can claim "special interests" have too much influence on the political process without including yourself in that category. We are not that stupid we cannot see the special interest you have in this matter. Your whole reputation is built on convincing people that the world as we know it will end if we don't stop emitting CO2. Don't you see that "special interests" must also include all the climate scientists & other government employees whose careers are based entirely on the premise that man is causing the planet to warm up & our response to it? I can only imagine that you will soon reveal how the world will replace the electricity generated by coal, as I am sure you would not want to see the world return to a pre-industrial age. I hope you have patented your ideas, as you would be richer than Bill Gates or Warren Buffet once the world starts using them. And you might get a Nobel prize like Al did, too.

In some ways, I applaud the

In some ways, I applaud the sense of urgency that accompanies the perceived need to do something to affect climate change. The need is there in more ways than you presently know. But the means could be another matter entirely. The Akkadian Empire under Sargon (2,300-2,200 BC), mankind’s first empire ever, succumbed to climate change that happened rather suddenly. A 300 year long period of drought struck this nascent civilization and toppled what turned out to be only a 100 year empire. The Old Kingdom of Egypt and the Harappans of the Indus Valley suffered a similar fate 4,200 years ago, succumbing to an abrupt drought that ended those civilizations, with Egyptians “forced to commit unheard of atrocities such as eating their own children and violating the sacred sanctity of their own dead (Fekri Hassan, 2001)”. The Mayans had pretty much the same luck with three periods of extreme drought at 810, 860 and 910 AD. Sadly just two years after the last drought which saw 95% of the Mayan population gone, wet years returned to the Yucatan. A reconstruction from fossil algae in sediments from Drought Lake in North Dakota of the past 2000 years found that dry conditions were far and away the rule in the High Plains, with the Dust Bowl conditions of the 1930’s one of the lesser dry spikes found in the record. Half of the warming that brought us out of the last ice age (the Wisconsin) occurred in less than a decade.

There were 24 Dansgaard-Oeschger oscillations between this interglacial, the Holocene, the interglacial in which all of human civilization has occurred, and the last one, the Eemian, in which the first fossils of Homo sapiens are to be found. D-O oscillations average 1,500 years, and have the same characteristic sawtooth temperature shape that the major ice-age/interglacials do, a sudden, dramatic, reliable, and seemingly unavoidable rise of between 8-10C on average, taking from only a few years to mere decades then a shaky period of warmth (less than interglacial warmth), followed by a steep descent back into ice age conditions. Each D-O oscillation is slightly colder than the previous one through about seven oscillations; then there is an especially long, cold interval, followed by an especially large, abrupt warming up to 16C. During the latter parts of the especially cold intervals, armadas of icebergs are rafted across the North Atlantic (Heinrich events) their passage recorded reliably by the deep ocean sediment cores which capture the telltale signature of these events in dropstones and detritus melted out of them. We know with absolute certainty that these events happen, with evidence of D-O oscillations extending back some 680 million years. We do not know yet precisely what causes them. What we do know is that the past 6 interglacials (dating back to the Mid Pleistocene Transition) have lasted roughly half of a precessional cycle, or 11,500 years, which just happens to be the current age of the Holocene. What we know is that N65 latitude insolation values are very close now to what they were at the close of the Eemian. What we also know is that GHGs seem to have played only a spectator role to all of these natural transitions, with temperature changes leading GHG concentrations by a considerable margin of time (800-1,300 years). What we do not know is if anthropogenic sourced GHGs can trigger a climate change event. What we do know is that earth’s climate is bimodal, cold (90%) and warm (10%), with the transition times (such as at the end of an interglacial) well known from proxy records to be quite sensitive to forcings we do not yet understand, and the forcings we have identified seemingly incapable of producing the responses we see in the paleoclimate record. Including the recent paleoclimate record.

The climb out from the Last Glacial Maximum of the Wisconsin ice age (called Termination 1 with sea level bottoming out about 121 meters, ~397 feet, below present) into the Holocene is studded with the Younger Dryas, a 1,300 year near instantaneous return to ice age conditions. “Briefly, the data indicate that cooling into the Younger Dryas occurred in a few prominent decade(s)-long steps, whereas warming at the end of it occurred primarily in one especially large step of about 8°C in about 10 years and was accompanied by a doubling of snow accumulation in 3 years; most of the accumulation-rate change occurred in 1 year (National Research Council, 2002)”. Almost as suddenly we came out of it: “Taylor et al. (1997) found that most of the change in most indicators occurred in one step over about 5 years at the end of the Younger Dryas, although additional steps of similar length but much smaller magnitude preceded and followed the main step, spanning a total of about 50 years (NRC, 2002)”.

Termination 1 began with what is referred to as Melt Water Pulse 1a (mwp-1a) centered at about 14,680 years ago which resulted in a 24 meter rise (about 78 feet) in sea level believed to have occurred at the rate of 4.5 cm (about 2 inches) a year. It was followed around 12,260 years ago by MWP-1b with a 28 meter (about 92 feet) rise nearer 5 cm per year. Recent model results predict that sea level is currently rising at 32cm/100 years. With natural rises clocked at 5cm/yr (or 500cm/century) we, (meaning us) have a lot of hard work ahead of us if we hope to trump mother nature’s most recent finest result.

Between 6,000 and 7,000 years ago, a period known to geologists and paleoclimatologists as the Holocene Climate Optimum, sea levels peaked about 6 meters (about 20 feet) higher than today, and during the Eemian Optimum, some 20 meters (about 60 feet) higher than today (some say 70 meters). During the seven post MPT ice ages, sea levels dropped some 100 or more meters below present, the water tied up in the miles thick ice sheets that have spread in North America as far south as Kansas. These are just some of the facts of the abrupt climate changes which we, as Homo sapiens, have experienced. General Circulation Models, of which the IPCC references 23, have yet to reproduce a single known abrupt paleoclimate change fed with the proxy data. The latest GCM models produce predictions based on a variety of input data and complex equations which few of us would understand. But for all the complexity and investment, they are just predictions.

Belief in, and acting as a result of, such predictions has opened up what may be the first chapter in faith-based science (W. should be so proud). Understanding the history of climate change provides a factual understanding of far more alarming climate changes that have actually happened, with sea level changes and temperature shifts that dramatically overshadow any faith-based prediction you have yet heard.

What might be quite ironic is that if GHG predicted global warming is in fact real, and, at half of a precessional cycle, we are near to the cliff of the next natural shift to an ice age, we may find ourselves needing to generate as much GHGs as possible to ease our transition into the next ice age. So as I said at the beginning, doing something about climate change is not necessarily a bad thing. Doing the right thing might actually be quite another. The ice ages and associated interglacials are well known to be paced by the eccentricity, obliquity and precession cycles in earth’s rickety orbit. These we will do nothing about. D-O oscillations show strong evidence of being tied to the 1,500 year cycle of solar output, something we cannot change.

So be ever thoughtful of both facts and predictions before leaping to a conclusion. It was in fact a LEAP that terminated the last interglacial, the cold Late Eemian Aridity Pulse which lasted 468 years and ended with a precipitous drop into the Wisconsin ice age. And yes, we were indeed there. We had been on the stage as our stone-age selves about the same length of time during that interglacial that our civilizations have been during this one.

Meanwhile, enjoy the interglacial!


"The leaders are members of the public who understand the situation and have the courage to act on it. "
The problem being that James Hansen, who claims to "understand the situation" has no "courage" to accept any invitation to debate the subject. Lord Mockington and Don Blankenship have recently extended invitiations to debate climate change. Hansen, showing no courage, runs from any offering of debate on the subject. He knows his work is greatly flawed and avoids any opposition that might expose this fact.

It's not Lord Mockington.

It's not Lord Mockington. His name is Monckton.

But perhaps you have it right after all.

See In Congressional Hearings, Amateurs Invited to Confuse Climate Science.

Hey there Courage

Don't know if you read or anything, but Hanson did accept the invitation from Blankenship, but the diplomatic way to say this is that there were "scheduling problems", and then Hanson got arrested.

I would love to see Blankenship try to discuss something like this with Hansen. The US's most preeminent climate scientist who's been on this for over 20 years vs. the CEO of a horrible company destroying Appalachian heritage. I think Hansen would stand on higher ground both factually and morally in a such a debate. It's obvious where I would place my bet.

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