THE NELSON LECTURE
1 July 2008
By Dr Gerrit J. van der Lingen
Climate Change Consultant
Background. I gave a public lecture, title GLOBAL WARMING AND COOLING in Nelson on July 1, 2008. I was asked to give this lecture by David Smale (retired geologist) on behalf of the Science Society and Ian Barker (Nelson City Councillor) on behalf of the Residents’ Association. The lecture was held in the City Council Chambers, Civic House.
As a good introduction and advertisement, on June 26 the *Nelson Mail *published my article titled OUR COOLING WORLD. However, they changed the title (as newspapers always seem to do). They also edited my text, fortunately without changing its meaning. They published it as follows:
Are we staring at global cooling?
By Gerrit van der Lingen
The deep sea around Antarctica is getting colder, the German research ship Polarstern from the famous Alfred Wegener Institute, has reported recently after summer studies as part of the International Polar Year. At the same time, satellite images showed the largest amount of summer sea-ice on record. This was not surprising, as the sea-ice cover around Antarctica during the previous winter was the largest since measurements by satellite begun in 1979.
Since 2000, about 3000 buoys have been deployed in seas around the world. The project is called Argos. The buoys automatically go up and down and measure sea temperatures (and salinity) to a depth of 2000 metres. After resurfacing, the buoys transmit their data via satellites to land-based stations. Since the start of their deployment they have recorded a slight cooling of the oceans.
But global temperatures have also not shown an increase since 1998 - if anything they have slightly cooled. This was reported by the UN World Meteorological Organisation, one of the two parent organisations of the Intergovernmental Panel on Climate Change. On May 4, the BBC published the following news item on its website: “Global temperatures will drop slightly this year as a result of the cooling effect of the La Niña current in the Pacific. The World Meteorological Organization’s secretary-general, Michel Jarraud, told the BBC it was likely that La Niña would continue into the summer. This would mean that global temperatures have not risen since 1998, prompting some to question climate change theory.”
La Niña, and its opposite El Niño, are natural climate oscillations. They are characterised by a change in air pressure between Darwin and Tahiti and a change in equatorial sea surface temperatures between the West Pacific and Peru. These events can last between 7 and 8 years. But there is an even longer-lasting oceanic oscillation, called the Pacific Decadal Oscillation. It fluctuates between cool and warm phases and has a strong influence on world temperatures. Last century it had a warm phase from 1905 till 1946, a cold phase from 1946 till 1977, and a warm phase since 1977. Recently, the PDO changed back to a cool phase. It is therefore not surprising that the last Southern and Northern Hemispheres experienced severe winters. We have all seen the TV pictures and newspaper articles about the severe winter storms in China, the worst in 50 years.
Last November, the European Alps received its largest snow dump in 40 years. North America was hit by severe snow storms. New Hampshire received the largest snowfall since 1873. Even the Arctic was affected. Sea ice cover between Greenland and Canada was the largest in fifteen years and the ice was 10-20 cm thicker than the year before. The entire Northern Hemisphere winter snow cover was the largest since 1966. It snowed in Baghdad and Jerusalem. The Southern Hemisphere was not spared. Argentina had an exceptionally cold winter. On November 17, 2007, Buenos Aires recorded its lowest temperature in 90 years. More dramatically, between January 2007 and January 2008, global temperatures plummeted by 0.6 degrees Celsius. This is almost as much as the total warming in the last 150 years.
The ultimate driver of our climate is the sun and historically, there is a close correlation between climate and sunspots. Solar activity (expressed by sunspot activity) is cyclic. The shortest cycle is 22 years, called the Schwabe Cycle (11 years minimal sunspots, 11 years maximum sunspots). There are larger solar cycles, such as the Gleissberg Cycle (88 years) and the Suess Cycle (208 years).
During the Little Ice Age (ca. 1300 - 1850) there were four exceptionally cold periods. During these periods there were few or no sunspots. The coldest was the so-called Maunder Minimum (ca. 1645 – 1715), when there were no sunspots for 70 years!
By analysing these sunspot cycles, astrophysicists are predicting that we may be going into a cold period that may be as severe as the last sunspot minimum of the Little Ice Age, the Dalton Minimum (ca. 1790 – 1830) and which could last for 30 years or more.
Since 1755, Schwabe sunspot cycles have been given numbers. We are now at the end of Cycle 23. A change from one cycle to another is indicated by a reversal of the magnetic polarity of sunspots. However, Cycle 24 is already 14 months overdue. Most of the time there are no sunspots at all. One can find information on sunspots on the Internet (www.solarcycle24.com). When I checked when writing this article (June 5), there had been no sunspots at all for 10 days. This is worrying. If the sun stays quiet, we may be in for a cold winter. According to NIWA, last May was already the coldest since 1992.
We can only hope that the astrophysicists are wrong in their predictions, as global cooling would be infinitely worse than warming. Each year, many more people die from cold than from warm temperatures.
Dr Gerrit van der Lingen obtained his PhD in geology from Utrecht University in The Netherlands. His first job was in Surinam (South America), where he worked in Amazon jungle for three years. In 1965 he came to New Zealand to join the Sedimentology Laboratory of the NZ Geological Survey. Since 1990 he worked as a private consultant and was Research Associate at the University of Canterbury. From 1991 till 2002 he was involved in paleoclimate research, studying ocean sediment cores from the Tasman Sea and Southern Ocean. He retired from paid research five years ago, but remains active as a climate change consultant, advising clients, giving lectures and writing articles.
Dr van der Lingen will give a public address on global warming and cooling in the Nelson City Council Chambers on July 1 at 7.30 pm, sponsored by the Nelson Residents’ Association and the Nelson Science Society.
A reporter from The Nelson Mail also interviewed me over the phone. On my request, she read her epistle to me before publishing it (on the same day as my article, 26 June 2008). There was only one minor mistake in the published version. The number of PhDs who signed the US petition was not “more than 900”, but “more than 9000”. The article read as follows:
Climate change scientist to visit
A retired Dutch climate scientist who says science shows that the Earth has been cooling for about a decade, not getting warmer, will speak in Nelson next week.
Dr Gerrit van der Lingen, whose visit to the region is being sponsored by the Nelson Residents' Association, told the Nelson Mail it was the sun that affected Earth's temperature, not the actions of humans.
"Human greenhouse gases have very little effect on climate change." Dr van der Lingen, a paleoclimatologist, said that while the world had warmed about 0.6 degrees C during the past 150 years, for about the past 10 years the climate had actually been cooling. He said the world's temperature had fluctuated during the past 2000 years, and in the medieval period it was Ideg to 2deg warmer than it was now.
He said the idea that carbon dioxide emissions could have a catastrophic effect on the world's climate was based on computer models, not science, and was one of the biggest "scams" in human history.
Dr van der Lingen said that when the Earth cooled, weather patterns were more extreme. For example, after the warm period in the Middle Ages there was a "Little Ice Age" from about 1350 to 1850, where extreme weather patterns were experienced. "If the cooling which is now going on continues, it could actually be catastrophic."
He said the number of scientists with similar views to himself was growing. This was shown by 32,000 scientists in the United States, including more than 900 with PhDs, signing a petition that the science of climate change was not settled and no convincing scientific evidence existed that the human release of carbon dioxide or other greenhouse gases was causing dangerous warming.
Dr van der Lingen will speak at 7.30pm next Tuesday in the Nelson City Council chambers. Entry is by gold coin. It is a Nelson Science Society talk, but is open to the public.
As is so often the case with the media, they could not publish my article without asking a MMGW believer to comment on it. The Nelson Mail asked Dr Peter Ballance, a colleague of mine and MMGW fanatic, to do so. His article was published a day later:
Cooling cancelled out by CO2
By Peter Ballance
Yesterday on this page Dr Gerrit van der Lingen put forward a case that the climate might be cooling, rather than warming as climate change/global warming theory suggests.
There is a conundrum here, because the climate should actually be cooling. For the past 10,000 years we have been receiving progressively less heat from the sun. This is not because the sun is putting out less heat overall (its output does vary up and down with sunspot cycles, as Dr van der Lingen stated) but because the long-term astronomical cycles known as Milankovitch Cycles move us through a 100,000-year cycle in which there is significant variation in the heat actually received. This is the cycle that drives glaciations.
Heat received was at a minimum 20,000 years ago, at the height of the last glaciation, and at a maximum 10,000 years ago, since when it has been declining. Heat received in the Northern Hemi¬sphere has the biggest effect, because there is so much more land there (land heats and cools much quicker than oceans do).
At 60N, heat received at midsummer has fallen from 525 to 475 watts a square metre in the past 10,000 years. This is the effect of the third Milankovitch cycle, the 20,000-year wobble of the Earth's axis, like the wobble of a spinning top. It moves first one hemi¬sphere, then the other, closer to the sun during summer. At present the Southern Hemisphere is closer, but the global warming effect of that is reduced because there is so much ocean.
When we look back at the ice-core record of the previous three inter-glacial periods, a brief period of maximum tem¬perature was followed by a steep cooling. That is what we would expect to have happened again this time, but it has not. So, the big question when considering changes in climate during historic time is: "Why is the world not getting cooler, since we've lost nearly 10 percent of our heat from the sun?"
Sure, there have been lots of shorter term ups and downs caused by natural processes like sunspot cycles, but the overall trend should have been downwards, and it hasn't been. In fact, world temperature has been remarkably stable for 10,000 years.
To answer that question, we need look no further than people. We began cutting down forests and turning over soil around 8000 years ago. Both those activities release large amounts of carbon, as the greenhouse gas carbon dioxide. By pure chance, the warming effect of our greenhouse gas output over several millennia cancelled out the Milankovitch cooling.
However, we've been overdoing it for the past 200 years, with the result that we read so much about, global climate change and global warming.
There's an old saying in science, that one person's noise is another's signal. The amateur radio ham chatting with a friend in Anchorage might have difficulty hearing the con¬versation (the signal) over the static (the noise). However, if the radio ham was also an atmos¬pheric physicist he or she might find the static very interesting and the con¬versation a nuisance.
The key to following cli¬mate change is to make a clear distinction between the twin signals of Milankovitch cooling and man-made global warming, on a time scale of thousands of years, and the noise of natu¬ral ups and downs on scales of decades to centuries.
The small but vocal group of climate change skeptics focus on the noise, and com¬pletely ignore the signals. They also promul¬gate incorrect facts and half-truths.Thus in the falsely named "documentary", The Great Global Warming Swindle -falsely named because it is itself a huge swindle - one participant states that water vapour provides 95 percent of the greenhouse effect. If that figure was correct it would relegate carbon dioxide to a very small effect, but in fact it is wrong. The true figure is around 60 percent for water vapour.
As to the apparent cooling of the past 10 years, that is patently either noise or a small manifestation of Milankovitch change. What's more, not all of Dr van der Lingen's examples of cooling are correct. He said that the 3000 ocean buoys of the Argo pro¬gramme have recorded a slight drop in ocean temperature. The Argo website now says, "A surprising suggestion that the oceans' heat content was diminishing, rather than increasing as expected, turned out to be an artifact caused by a software glitch."
A global temperature fall of 0.67C between January 2007 and January 2008, noted by Dr van der Lingen, is indeed simi¬lar in magnitude to the global average increase over the past century, but the com¬parison is misleading. Detailed temperature records go up and down like a yo-yo, and there were similar falls between 1990 and 1993, and 1998 (the warmest year yet) and 2000.
It may well be that sunspot cycles will drive temperatures down over the next few decades, but it may also be that the greenhouse gases we are pouring into the atmosphere at ever increasing rates will trump the sunspots. At any rate, Milan¬kovitch cooling may be our only hope of tem¬pering the large global warming that we are stoking with such misguided enthusiasm.
Dr Peter Ballance has PhD and DSc degrees from London University, and taught sedimen¬tary and historical geology at Auckland Univer¬sity from 1960 to 1997. He has a particular interest in sedimentary and volcanic processes at convergent plate margins, such as the one that New Zealand sits astride. He moved to Nelson in 2000.
My comment: The idea that humans have been warming the planet for the last 8000 years comes from William Ruddiman, a marine geologist. His hypothesis was published in Scientific American of March 2005. It was an interesting idea, but not supported by solid evidence. It basically said that human agricultural activities over the past 8000 years increased carbon dioxide levels by about 40 ppmv above levels in earlier interglacials, and that over the past 5000 years methane levels increased about 250 ppbv. Both these values were reached before the beginning of the industrial revolution. His warming hypothesis was based on comparisons with earlier interglacials and the workings of the Milankovitch cycles. He implied that those cycles were very regular. But the increases from human greenhouse gases are extremely small. To obtain his warming hypothesis, he plugged his figures into computer models, which gave him a warming of almost 0.8 degrees C over the period from 8000 years ago until the beginning of the industrial revolution. Although Dr Balance revived Ruddiman’s hypothesis, I haven’t heard much more about it since 2005. Moreover, let’s not forget that the warmaholics recently subtly changed their hypothesis. They now say that man-made warming did not happen since the beginning of the industrial revolution, but only in the last 50 years.
The lecture itself went very well. There was a large crowd and many had to sit on the floor or were standing at the back. Councillor Ian Barker chaired the meeting and kept a strict rein. There would be no interruptions during my talk. Afterwards there would be 30 minutes for questioning. Only one question per person allowed and not taking more than one minute each. Finally, there would be ten minutes during which people could make statements without discussion. This latter item was new to me. Everything went smoothly. The discussion was very good. I was surprised by several questions by people who obviously were skeptical about the MMGW hype. That was very encouraging.
A reporter of The Nelson Mail wrote a review of my talk, which appeared in next day’s (2 July) paper. It read as follows:
Climate-change views welcomed
A retired Dutch paleoclimatologist who has labelled man-made global warming the biggest scam in human history has had a warm reception in Nelson.
People packed the Nelson City Council civic chambers on Tuesday night to hear Dr Gerrit van der Lingen speak.
At the end of his talk Dr van der Lingen thanked the audience for what he said was a frank discussion and the best presentation he had experienced.
He had earlier joked that friends had told him to expect a rough reception from “greenies” in Nelson.
Dr van der Lingen had previously written in the Nelson Mail that science has shown that while the Earth has warmed in the past 150 years by 0.6 degrees C, it has actually been cooling for the past 10 years.
He believes that the debate on climate change is far from settled and that the idea that carbon dioxide emissions are causing global warming to catastrophic levels is wrong.
He said Earth’s temperature had fluctuated during the past 2000 years and the activity of the sun had a stronger effect on climate change than greenhouse gases.
During question time, one man thanked Dr van der Lingen for being brave enough to talk in public about what he had believed for years. Dr van der Lingen replied that it was not about being brave, but about the science speaking for itself.
At the conclusion of the speech, members of the audience had an opportunity to give their opinions on it.
One man said he believed global warming was irrelevant and that the real threat to Earth was the fact that humans had depleted so much of its resources.
Another man said governments were planning to spend trillions on planning for global warming, money that could buy a lot of health care and education. Governments should be listening to climatologists rather than scientists, he said.
However, another man said Dr van der Lingen’s speech had focussed on the past, and that humans had been running a very big experiment by pumping a lot of greenhouse gases into the atmosphere. The question was what would happen now.
Another said it was the job of planners to plan for risk, and if the majority of scientists said the Earth was warming, with some potentially scary consequences, an intelligent risk analysis would plan for those changes.
Not a bad review. The only incorrect statement is that I talked about fluctuating temperatures during the past 2000 years. I had discussed the last 3 billion years of climate change.
All in all a satisfying trip north. As I experience more and more, there is a lot of healthy scepticism about MMGW in the general public. Even in Nelson.