TO A GEOLOGIST, THE PAST IS KEY TO THE FUTURE

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1 TO A GEOLOGIST, THE PAST IS KEY TO THE FUTURE by Steve Goddard SPPI ORIGINAL PAPER October 21, 2010

2 TO A GEOLOGIST, THE PAST IS KEY TO THE FUTURE by Steve Goddard October 21, 2010 In order to understand recent behavior of polar ice and have some visibility into the future, we need to look at it from an historical perspective. A good place to start the investigation is Greenland, which is often described by official sources as experiencing a meltdown. The BBC has famously warned us If the ice cap were to completely disappear, global sea levels would rise by 6.5m (21 feet). NASA s Goddard Institute of Space Studies (GISS) has long term temperature records for several locations in Greenland and Iceland. The graph below shows average annual temperatures in the Greenland capital for the last 100 years. Over the last 30 years, Godthab has warmed by several degrees, as shown with the red line. But the one hundred year trend (yellow line) shows a slight cooling. Peak yearly temperatures during the past decade are about one degree cooler than peak years in the 1930s and 1940s. There also appears to be a cyclical pattern of warming and cooling in Godthab. Temperatures warmed until 1940, cooled in the 1960s and 1970s, and warmed again starting in the 1980s. The graph below shows the Godthab temperature record again, this time with the ten year running mean in red. 2

3 Other GISS Greenland and Iceland locations with long-term records show similar patterns. The ten year running mean in red. 3

4 NASA and NOAA Satellites have been monitoring Arctic temperatures and ice since the late 1970s. Coincidentally, they were put into service when much of the Arctic was near its coldest point of the last 100 years. Given the timing of the launches, we should not be surprised that the satellite record has shown warming temperatures and decreasing ice. Looking closer at the Greenland/Iceland temperature graphs, it can be seen that the warming over the last 30 years is nothing out of the ordinary, and is indeed similar to the warming seen from 1910 to

5 The 1910 to 1940 warming period was actually warmer than the current one, yet it occurred at a time when atmospheric CO2 levels were much lower and well below Dr. Hansen s safe level of 350 ppm. Between 1910 and 1940, CO2 levels increased by only 10 parts per million, from 300 ppm to 310 ppm. So we can see that Greenland went through a greater warming period when CO2 was both lower, and increasing more slowly - which is not at all consistent with global warming theory. What about other historical records? We know from press accounts that the 1970s was a cold period, with extensive Arctic ice. Famous stories from Newsweek and Time Magazines highlighted concerns of a Coming Ice Age. Newsweek even suggested that we might want to intentionally spread soot on the Arctic ice to stop its spread. Climatologists are pessimistic that political leaders will take any positive action to compensate for the climatic change, or even to allay its effects. They concede that some of the more spectacular solutions proposed, such as melting the Arctic ice cap by covering it with black soot or diverting arctic rivers, might create problems far greater than those they solve. But the scientists see few signs that government leaders anywhere are even prepared to take the simple measures of stockpiling food or of introducing the variables of climatic uncertainty into economic projections of future food supplies. The longer the planners delay, the more difficult will they find it to cope with climatic change once the results become grim reality. Besides those well-known stories, there were many others. Most of the references below were tracked down by BMI (The Business and Media Institute.) Washington Post : July 9, 1971 US Scientist Sees New Ice Age Coming LA Times : Oct 24, 1971 New Ice Age Coming---It's Already Getting Colder 5

6 Chicago Tribune : October 30, 1974 Ice Age, worse food crisis seen Science News : March 1, 1975 The Ice Age Cometh New York Times : May 21, 1975 Scientists Ponder Why World s Climate is Changing; A Major Cooling Widely Considered to Be Inevitable US News : May 31, 1976 Worrisome CIA Report; Even U.S. Farms May be Hit by Cooling Trend 6

7 Christian Science Monitor : November 14, 1979 New ice age almost upon us? It is unfortunate that the satellite record started near the minimum of a cold period. For some people whose historical visibility is limited to 30 years, it looks like Greenland is baking. But for those with a longer term view, there is nothing unusual happening. In 1922, the US Weather Bureau reported :... Capt. Martin Ingebrigtsen, who has sailed the eastern Arctic for 54 years past. (He) says that he first noted warmer conditions in 1915, that since that time it has steadily gotten warmer, and that to-day the Arctic of that region is not recognizable as the same region of 1865 to Many old landmarks are so changed as to be unrecognizable. Where formerly great masses of ice were found, there are now often moraines, accumulations of earth and stones. At many points where glaciers formerly extended far into the sea they have entirely disappeared. Sounds familiar? We hear the same story now from researchers and explorers in Greenland and the Antarctic Peninsula. So far, we have looked primarily at the Atlantic side of the Arctic. But what about the other side? The Google Earth map below shows GISS temperature trends in the Arctic over the last 70 years. Turquoise dots have cooled during that period, while red dots have warmed. Most of the Arctic has cooled, but the Pacific side has warmed. 7

8 The graph below from the University of Alaska provides more detail about the Pacific warming. Temperatures in Alaska rose sharply in 1977, when the Pacific Decadal Oscillation (PDO) shifted from its cold phase to its warm phase. Since then, temperatures in Alaska have scarcely changed. We can conclude that the 70 year warming in Alaska was due to a cyclical change in ocean circulation, not global warming. There was no dramatic shift in atmospheric CO2 during the year The next graph superimposes Alaska temperatures on the five year running mean of ENSO (El Nino Southern Oscillation) which is a measure of the warmth of the equatorial Pacific. As you can see, there is nearly a perfect correlation between a warm Pacific and a warm Alaska. 8

9 ARCTIC SEA ICE Similarly, Arctic sea ice has declined in conjunction with the warm ENSO cycle since the late 1970s. The same ice graph is shown below, superimposed on the ENSO graph. 9

10 We know from NSIDC (National Snow And Ice Data Center) data that most of the older multi-year ice was lost between 1988 and 1996, during a particularly warm period in the Pacific Ocean. GLACIERS Glaciers have been receding in Alaska and elsewhere. One of the more famous glaciers is at Glacier Bay, Alaska. Wikipedia Image : John Muir at Glacier Bay in 1893 Since 1760, the glacier has receded many miles. Yet the USGS map below shows that almost all of the retreat occurred prior to the invention of the automobile. Given the timing, this retreat could not have been related to changes in atmospheric CO2. 10

11 Globally, glaciers have been retreating for at least 15,000 years, since the end of the last ice age. At the peak of the last ice age, glaciers covered almost all of Canada - as well as much of the US and Europe. Chicago and New York were buried under a mile of ice. Natural changes in the climate caused the vast majority of that ice to melt, and the long-term trend of disappearing glaciers continues to the present. Glacial melt is not something new. 11

12 Wikipedia image : Approximate extent of glacial ice 18,000 years ago Based on: "Ice age terrestrial carbon changes revisited" by Thomas J. Crowley Yosemite Valley was carved out during several periods of glaciation from one million to ten thousand years ago. 12

13 Wikipedia Image SEA LEVEL Where did the glacial ice go when it melted? All of the melt water necessarily returned to the sea. We know that sea level has risen 130 metres since women and men first crossed the Bering Strait into North America. During one relatively short period fourteen thousand years ago, sea level rapidly rose about 100 feet. This had nothing to do with the behaviour of humans occupying the planet. Glaciers have been melting and sea level rising for a very long time. 13

14 Global Warming Art image MORE ON SEA ICE Now let us turn our attention back to Arctic sea ice - the ice which floats in the ocean. There has been considerable discussion in the press about the near certainty of a sea ice free Arctic in the not too distant future. A number of well-respected experts have estimated complete loss of summertime ice - occurring sometime between 2008 and Yet an ice free Arctic Ocean is not even remotely possible during most of the year, because temperatures in the high Arctic are well below freezing for eight to nine months every year. Does it make sense to extrapolate into the future and forecast the demise of the ice, or would it be more sensible to take into consideration that Arctic temperatures are cyclical? Many leading scientists have chosen the former. John Holdren - President Obama s Science Advisor - mentioned the possibility of ice free winters. if you lose the summer sea ice, there are phenomena that could lead you not so very long thereafter to lose the winter sea ice as well. And if you lose that sea ice year round, it s going to mean drastic climatic change all over the hemisphere. 14

15 Dr. Olav Orheim, the Norwegian International Polar Year Secretariat, remarked in 2008 : "If Norway's average temperature this year equals that in 2007,the ice cap in the Arctic will all melt away (in 2008), which is highly possible judging from current conditions" Professor Wieslaw Maslowski of the Naval Postgraduate School forecast an ice free Arctic by the year "Our projection of 2013 for the removal of ice in summer is not accounting for the last two minima, in 2005 and So given that fact, you can argue that may be our projection of 2013 is already too conservative." Dr. David Barber from the University of Manitoba has forecast an ice free summer by the year Things are happening much faster in the Arctic. I think it will be summer ice-free by 2015, As an historical note, in 1969 the New York Times published a prediction that the Arctic Ocean Will Soon Be an Open Sea. This predictions from leading experts appear somewhere between very unlikely and absurd. How could they be so far off the mark? Their claims seem to be based on the idea that Arctic summers are warming very rapidly. It is true that some areas of the Arctic Basin have seen warm summers recently, but not near the pole. In order for the Arctic to become ice free, the entire Arctic would have to melt - including the North Pole. The Danish Meteorological Institute has been keeping track of high Arctic temperatures (north of 80 degrees latitude) since Their data shows that the warming which has occurred over the last 30 years has been primarily during the winter, and that summers near the pole have actually cooled. The just completed Arctic summer (north of 80N) was one of the coldest on record, with temperatures below normal for almost the entire summer (mid- June to mid-august.) 15

16 In spring 2008, Mark Serreze at NSIDC noted that the ice at the North Pole was thin first year ice, and forecast that the North Pole might be ice free that summer. But the ice did not melt out at the pole, because temperatures were too cold. This casts doubt on the possibility of an ice free Arctic in the near future - because no summer will ever start with ice younger than it was in 2008, and because summer temperatures have not been warming near the pole saw the lowest Arctic ice extent in the satellite record. During that year winds were particularly strong and persistent - which caused the ice to melt, compact, and pile up against the coast of Canada and Greenland. The US Navy PIPS2 ice forecast system showed that the average ice thickness in September, 2007 was the greatest of any recent year. This was due to compaction of the ice by the wind. An analogy is shoveling the snow in your driveway into a pile. The area of the snow decreases, while the average thickness increases. During the following winter, much of the thicker multi-year ice blew out into the North Atlantic and melted. The graph below from the Japan Aerospace Exploration Agency highlights what happened in

17 The Guardian reported in March, 2010 Much of the record breaking loss of ice in the Arctic ocean in recent years is down to the region's swirling winds and is not a direct result of global warming, a new study reveals. Ice blown out of the region by Arctic winds can explain around one-third of the steep downward trend in sea ice extent in the region since 1979, the scientists say. The study does not question that global warming is also melting ice in the Arctic, but it could raise doubts about highprofile claims that the region has passed a climate "tipping point" that could see ice loss sharply accelerate in coming years. The key points to remember about the Arctic are: 1. Arctic temperatures are cyclical. 2. The Atlantic side of the Arctic was warmer 70 years ago. 3. Temperatures on the Pacific side of the Arctic are controlled by the Pacific Decadal Oscillation, which may have recently gone back to its cold phase. 17

18 4. Satellites came on line when Greenland was at its coldest level of the last century. Thus it is not surprising that we have seen warming temperatures and ice loss. 5. The ice loss which has been observed has been largely due to wind. 6. Summer temperatures near the North Pole have not warmed. 7. The melt season is very short at the North Pole. 8. The same winds which caused the 2007 record low extent, also piled the ice up thicker at high latitudes. This pattern makes an ice-free Arctic less likely. not more likely. An ice-free Arctic would require that the ice spreads and melts, not piles up and thickens. ANTARCTICA So far, the discussion has been about the Arctic, because the press prefers to talk about ice loss. But most of the world s sea ice is actually located near the South Pole, which has actually been gaining ice through the satellite record - as seen in the NSIDC graph below. In fact, the total amount of sea ice on Earth has scarcely changed through the satellite record. 18

19 If the trend continued, the Earth would have sea ice for at least 600 more years. But since Antarctic ice is increasing, there is no reason to expect that current weather trends would ever lead to an ice free earth. CONCLUSIONS 1. The widespread belief that the poles are rapidly melting down is incorrect, particularly in the Southern Hemisphere. 2. Arctic temperatures are cyclical. Much of the Arctic has been warmer during the last 100 years. 3. The satellite record from coincided with the warm phase of the PDO. It covers less than one half of an Arctic temperature cycle. Given this cyclical behavior, it makes little scientific sense to extrapolate linearly based on a time period which is too short. Until satellites record at least one entire Arctic cycle, the extrapolations are misleading. 4. There is little (if any) evidence linking recent changes in the Arctic to CO2. At this point there is no solid reason to believe we are seeing anything other than natural Arctic cycles. Greenland temperatures are cooler than 70 years ago. 19

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