Tuesday, February 26th 2013, 8:58 AM EST
Robert W. Endlich
I attended a talk by Dr. James Hansen, head of NASA’s Goddard Institute of Space Sciences on effects of climate change on 21 Feb 2013. James Hansen is also famous for being arrested, reportedly three times, for protesting the use of fossil fuels and the consequent emission of CO2 into the atmosphere.
Dr. Hansen’s talk was illustrated by of a number of slides depicting topics concerning surface temperature history, sensing systems, and paleoclimate history. His delivery rarely spoke to the content on the screen, and often rambled into opinions on the evils of fossil fuel use, dangerous rapid temperature rise, approaching “tipping points,” and the need to heavily tax fossil fuel use.
One item after another struck me as being completely at odds with measurements. For instance, Hansen claimed Earth’s energy balance is out of balance, and we are warming rapidly, but recent global surface temperatures of land and water have not increased and in fact many measures show cooling over the past 17-19 years. In the US, there has not been a new state maximum temperature record set since 1995, and in spite of the claims to the contrary, July,1936, is still the warmest month on record, set when CO2 was less than 300 parts per million. CO2 is now 395 PPM.
Many in the audience loved Hansen’s claims, and the hall was replete with attendees wearing blue “350” buttons, indicative of support for Bill McKibben of 350.org, a climate alarmist organization, and several were carrying Hansen’s book, “Storms of my Grandchildren” an alarmist science fiction piece.
The talk was 45 minutes long, with 15 minutes allotted to questions and answers. Dr. Hansen is adept at President Obama’s knack of turning a question into an invitation to wax at length on opinions on anything vaguely related to the question. There were four questions; I asked number three.
My question was, roughly, “Dr. Hansen, one of your slides showed a time series of warming periods, indicated by reds, and cooling periods, indicated by blues, over time, indicating to me that climate warming and cooling periods are the norm. But, your 1988 forecast to the Senate was for continuous increases in temperature, about 1C of warming, from 1988 to the present. Observations show 10 years of warming from 1988 to 1998, but steady and by many measures, even falling temperatures since, a period over 17 years where the temperature has not risen at all. The total rise since 1988 has been only 0.2 - 0.3C. To what do you attribute the poor performance of that prediction?”
Hansen’s reply wandered around, saying there were three scenarios forecast and that actually the climate forcing was less than the “Business as Usual, Scenario A.” (In the basic talk he bemoaned CO2 emissions from fossil fuel use were on an ever increasing curve; to me, a non-sequitur) He then said that temperatures had NOT decreased, despite the fact that seven of the nine commonly watched measurements of global land, sea, and greenhouse temperatures have shown falling temperatures since at least 2001 during this time of increasing CO2. He then said I should have seen his 1983 paper and the forecast he made back then!
It has been 34 years since I have been in Graduate School. I was disappointed that a world-renowned researcher could not provide a cogent, coherent answer to a pertinent question regarding accuracy of the forecast which brought him to prominence. “How has this guy passed his candidacy exam or prelims?” I thought.
When formal questions were over, a number of attendees approached the podium; I joined the group. At my turn, I asked him a question about the paloeclimate records he referenced during the talk. I showed him a graphic of temperature and CO2 vs. geologic time with data provided by Berner and Scotese, which you can see if you Google “Berner Scotese Geologic CO2 Temperature Graph”.
I asked him about two periods in geologic history. First was end of the Ordovician, about 450 million years ago when CO2 increased from 4000 to 4400 PPM but earth entered a “snowball earth” phase. Second was the end of the Jurassic 150 million years ago, when CO2 was increasing, but temperatures fell. He told me that the data were wrong.
I specifically asked him about the measurements which showed large amounts of CO2 during the Cambrian and Ordovician about 4000-6000 PPM, and that even the IPCC speaks of large amounts of CO2 in the early Paleozoic. He said that there were no measurements of large CO2 amounts in the Paleozoic and again said I was wrong. I guess he has not heard of the Royer Compilation
I then asked about the Vostok Ice Core data which shows four previous interglacial periods CO2 was about 200-270 PPM, and temperatures were clearly much warmer that the present. “Dr Hansen, doesn’t the fact that the previous interglacials were a lot warmer than now, falsify the claim that CO2 is an important driver of climate?” He argued with me that the Vostok Ice core data did not show this, and said I was wrong. Google http://en.wikipedia.org/wiki/File:Vostok-ice-core-petit.png to see the data yourself.
Finally, I told him that the Greenland Ice core data showed that during the present interglacial period, temperatures were at a maximum 8000 years ago and have cooled overall since then. I asked him if CO2 has an important effect on climate, how this could be, and I said that there was nothing alarming about the present temperatures and rate of change of temperature. He told me that I was wrong again and his data showed today is the warmest in the Holocene Interglacial period. Google “Greenland Ice core data graph GISP2” and examine the geologic record showing temperatures and temperature changes to see how wrong Hansen is regarding this fact.
Hansen says the science is settled and there are no data which contradicts the alarmist view of imminent catastrophic temperature change and tipping points.
Who is the “denier?”
Hansen can’t accept the fact that measurements, observations, facts and data show that present temperatures are quite ordinary and that the rates of temperature change are among the smallest of the past 10,000 years, despite present CO2 concentrations.