Science

An article appearing in the April 19 issue of Science looks at how accurately climate models are able to reproduce current and past climate. What the authors conclude is that the models do a decent job of simulating the observed data, but that the data itself may not be that good.

“We can now test how well climate models simulate century-scale variations in the observed climate record,” say the authors, Thomas Smith, Thomas Karl and Richard Reynolds, at the National Climatic Data Center. “There have been numerous intercomparisons of various climate model simulations of 20^th-century climate, based on the best available estimates of the climate forcing.”

It is assumed that these simulations closely reproduce observed climate variability, but, “This assumption mustbe viewed with caution,” say the authors. “Observational errors, sampling errors, and time-dependent biases degrade the climate record.” Although researchers have attempted to remove these errors, there are still problems.

The authors compare the errors in the computer models with the errors in the observed temperature record of worldwide sea surface temperatures (SSTs) which stretch back to the 19^th century. To illustrate model errors the authors run three separate computer simulations with identical forcings, but starting at different initial conditions. By doing this they were able to “estimate the magnitude of the uncertainty introduced by a chaotic climate system.”

For the observed temperature record the authors calculated the uncertainty by comparing the range of SSTs derived from different observational errors, sampling errors and time-dependent bias adjustments. “The errors in analyzed SSTs,” say the authors, “are comparable to the uncertainty estimate associated with climate chaos over much of the 20^th century.”

They conclude, “Todays models are thus within the observed uncertainty of the observations, at least with respect to the global SST record. This does not imply that the model simulations are perfect; rather, it indicates that more attention must be given to improving the records of past climate and ensuring that future climate records have little or no time-dependent biases.

“It is unsettling that the uncertainty related to treatment of the data is increasing in recent decades in the most-sampled oceans. This points to the importance of developing a global observing system that not only has good spatial coverage, but more importantly, strictly adheres to guidelines and principles articulated by the U.S. National Academy of Sciences.”

Etc.

• In an April 21 editorial in the New York Times, former Vice President Al Gore called Dr. Rajendra Pachauri, the new chairman of the United Nations Intergovernmental Panel on Climate Change, a “lets drag our feet candidate who is known for his virulent anti-American statements.”

Dr. Pachauri responded in a letter to the editor in the May 1 New York Times, stating, “Mr. Gores derogatory statements about me reflect a deep disappointment at my election as chairman of the [IPCC], with 76 votes for me against 49 for his protg, Dr. Robert T. Watson.

“In a 1999 speech, Mr. Gore, referring to my commitment, vision and dedication, said; Pachy is the one person in the world who could bring us all here. He is known all over the community of concerned men and women as someone with the intellect and the heart.

“In Earth in the Balance, Mr. Gore acknowledged me among the other scientists who have been helpful in giving me advice during the writing of this book.

“Would the real Al Gore stand up? Does what he says today hold no value tomorrow?”

Announcements

• The Cooler Heads Coalition together with the Science and Environmental Policy Project and Frontiers of Freedom will hold a briefing on “Whatever Happened to Global Warming?” on Monday, May 13, from Noon to 2 PM in Room B-339 of the Rayburn House Office Building. Speakers will include John Daly, who runs the highly regarded Still Waiting for Greenhouse web site in Australia, and climate scientists from Europe and North America. Lunch will be served. Attendance is free of charge, but reservations are required. Please contact Ericka Joyner of CEI at (202) 331-1010, ext. 267, or e-mail her at ejoyner@cei.org. Include your name, affiliation, and phone number.

Changes in European Growing Season Due to Natural Factors

A study in the February 2002 issue of the Journal of Climate looks for possible explanations for the advent of earlier growing seasons in Europe other than global warming, noting that there is “a strong variability in the timing of seasons in Europe, which is perceived as a signal of a global climate change.” According to the researchers, led by Paulo DOdorico with the Department of Environmental Sciences at the University of Virginia, “The study of the interannual variability of timing and length of the growing season is gaining importance because plant phenology [biological response to climatic conditions] is a sensitive indicator of climate change and has broad impacts on terrestrial ecosystems through changes in productivity and in the annual carbon and water cycles.”

The study looks at the relationship between the North Atlantic Oscillation (NAO), “a large-scale displacement of air mass between the subarctic and the subtropical regions of the North Atlantic,” and the early onset of the spring season. What they found is that “spring phenology in Europe is found to be significantly affected by the North Atlantic Oscillation.” In fact, the researchers characterize the dependence of the early spring on the phases of the NAO as “remarkable.”

Amazon in Carbon Balance

A new study in Nature (April 11, 2002) has found that the rivers and wetlands of the Amazon rainforest may emit as much carbon dioxide as the dry regions of the forest absorb. This suggests that the Amazon may be in carbon equilibrium.

The researchers, led by Jeffrey E. Richey with the School of Oceanography at the University of Washington, conclude that, “Estimates that the tropics are a net carbon sink are not consistent with recent calculations from global inverse modeling, which imply that the tropics are at least in balance with the atmosphere if not a net source.”

In other words, the Amazon may not be a net carbon sink. If true, scientists will have to search for other carbon sinks to account for large amounts of carbon dioxide emissions, both natural and anthropogenic, that do not end up in the atmosphere and are not accounted for by known carbon sinks. These findings, however, will help scientists get a better handle on mans contribution to climate change, if any.

Etc.

The National Post (April 13, 2002) has reported that, “The world’s most powerful environment ministers will ride in buses powered by natural gas and greenhouse gas credits have been exchanged to negate their environmental impact on Banff, a World Heritage Site, during meetings here this weekend.” As a result of air and car travel and hotel accommodations the ministers attending the G8 environmental summit meeting last weekend would be responsible for tons of carbon dioxide emissions.

“However, under the scrutiny of environmental organizations gathered here,” reported the National Post, “the ministers have attempted to avoid embarrassment by purchasing carbon-dioxide credits from a solar-powered housing project in South Africa that will make the gathering an emission-neutral meeting, said David Anderson, Canada’s Minister of the Environment.” The ministers also dined on organically grown food.

A period of high global temperatures near the beginning of the last millennium closely matches the warming witnessed, about one degree Fahrenheit, during the 20^th century, according to a new study in the March 22 issue of Science.

The studys authors, Drs. Jan Esper and Fritz Schweingruber at the Swiss Federal Research Institute, and Edward Cook at the Lamont-Doherty Earth Observatory, state that “Much of the current debate on the Earths climate variability is driven by the observation of a modern, century-long temperature increase, culminating with the last decade of the 20^th century as the warmest since 1856.”

Using tree ring data from 14 different sites on three different continents in the Northern Hemisphere, the researchers constructed a temperature record of the last 1000 years. What they found was that the “MWP [Medieval Warm Period] was likely to have been a large-scale phenomenon in the NH [Northern Hemisphere] extratropics that appears to have approached, during certain intervals, the magnitude of 20^th-century warming, at least up to 1990.”

This finding contradicts an earlier study by Mann, et al. that appeared in Geophysical Research Letters in 1999. That study combined tree ring data and the instrumental temperature record and “shows an almost linear temperature decrease from the year 1000 to the late 19^th century, followed by a dramatic and unprecedented temperature increase to the present time,” according to Esper, et al. That study served as the basis for claims in the Third Assessment Report of the United Nations Intergovernmental Panel on Climate Change that the current warming is greater than at any other time in the last 1000 years.

A commentary that accompanies the study notes that, “The warming of the 20^th century is seen more clearly as a continuation of a trend that began at the start of the 19^th century, not the early 20^th.” It also notes that, “the curve of Esper et al. provides evidence for greater climate variability in the last 1000 years than has yet been generally accepted.”

“We dont use this as a refutation of greenhouse warming,” Edward Cook told CBS News. “But it does show that there are processes within the Earths natural climate system that produce large changes that might be viewed as comparable to what we have seen in the 20^th century. Greenhouse gases were not a factor back in the Medieval Warm Period.”

No Link Between Global Warming and Malaria

A new study in the February 21 issue of Nature tests the proposition that higher incidences of malaria in the East African highlands are caused by global warming. The studys authors, led by Simon Hay at Oxford University, could not find a link between the two phenomena.

The study examines the long term trends in meteorological data from four East African sites that have recently experienced a significant resurgence in malaria cases. As noted in the study, “The suitability of each month for Plasmodium falciparum malaria transmission depends on a combination of temperature and rainfall conditions.” The researchers looked for changes in these climate variables that might explain changes in the incidence of malaria.

What they found was that “Temperature, rainfall, vapor pressure, and the number of months suitable for P. falciparum transmission have not changed significantly during the past century or during the period of reported malaria resurgence.” These findings are not “consistent with the simplistic notion that recent malaria resurgences in these areas are caused by rising temperatures.”

The studys authors explain that there are several other factors that have contributed to the resurgence of malaria in East Africa, including antimalarial drug resistance, population migration, and breakdowns in public health and vector control operations. Thus, according to the authors, “Economic, social and political factors can therefore explain recent resurgences in malaria and other mosquito-borne diseases with no need to invoke climate change.”

Abrupt Climate Change and the Thermohaline Circulation

Two recent studies cast doubts on the claim that global warming could lead to increased climate variability and to the cessation of the climatically important thermohaline circulation (THC). The THC is a conveyer-like circulation in the Atlantic Ocean where “Near-surface currents bring warm, saline waters from the subtropics to high northern latitudes where they are cooled by the atmosphere, sink to depths between 2,000 and 3,000 meters, and flow back south as a deep western boundary current,” according to the study in Science (February 22, 2002).

This circulation is important because, “The ocean affects climate through its high heat capacity relative to the surrounding land, thereby moderating daily, seasonal and interannual temperature fluctuations, and through its ability to transport heat from one location to another,” as noted in the study appearing in Nature (February 21, 2002). If the THC were to cease, it would lead to dramatic cooling in Europe.

The Nature study states that, “Most, but not all, coupled GCM [global circulation model] projections of the twenty-first century climate show a reduction in the strength of the Atlantic overturning circulation with increasing concentrations of greenhouse gases if the warming is strong enough and sustained long enough, a complete collapse cannot be excluded.”

But due to model deficiencies and uncertainties about how the climate system responds to greenhouse forcings, it is difficult to determine the likelihood of future changes in the THC. To remedy this problem, the authors believe that scientists should examine the palaeoclimate record, which “provides the fundamental basis for evaluating the ability of models to correctly simulate behavior of the THC.”

What the palaeoclimate record shows us is that abrupt climate changes due to changes in the THC are not characteristic of the current warm interglacial period known as the Holocene. But such changes “were characteristic of the last glaciation.” The authors conclude that, “The palaeoclimate data and the model results indicate that the stability of the thermohaline circulation depends on the mean climate state.” Since abrupt changes are confined to glacial periods and not characteristic of interglacial periods it is unlikely that global warming will have any effect on the THC.

The study appearing in Science attempts to find an explanation for abrupt climate changes that have been discovered in the palaeoclimate data. The study notes that, “In contrast to the relatively stable climate of the past 10,000 years, during glacial times the North Atlantic region experienced large-amplitude transitions between cold (stadial) and warm (interstadial) states.”

Using climate models, the authors determine that “reduced calving of icebergs into the North Atlantic after a widespread ice sheet surge constitutes a trigger for the rapid glacial warming events,” which follow a few hundred years later.

In other words, ice sheet surges during glacial periods are characterized by rapid calving of icebergs that inject fresh water into the North Atlantic, reducing salinity. The resulting fall in sea water density prevents sinking, which then stops the THC.

The rapid calving that follows the ice sheet surge causes the ice streams to retreat from the coastline, and calving eventually ceases. Over time, the absence of freshwater input leads to greater salinity and the THC starts up again leading to an abrupt warming.

Both of these studies demonstrate that, contrary to climate model predictions, a warmer climate is more stable and that colder glacial climates are subject to significant climate variability and more extreme weather events.

A Warmer Climate Means Less El Nio Activity

Another issue related to global warming and climate variability is the claim that a warmer climate will lead to greater El Nio activity. A study in the February 22 issue of Science shows that a warmer climate will likely lead to lesser rather than greater El Nio activity.

The authors examine the oxygen isotope profiles of excavated otoliths “aragonite structures in fish used for acoustic perception and balance” from Peruvian sea catfish. Because the oxygen that is incorporated into the otoliths is in isotopic equilibrium with the seawater, scientists can use them to derive past sea surface temperatures.

What they found was that during the mid-Holocene, from around 6,000 years ago, sea surface temperatures were three to four degrees C higher than they were over the decade of the 1990s. The authors cite several studies that show that El Nio conditions did not exist prior to 5,000 years ago, which mean that warm sea surface temperature are likely to reduce El Nio activity rather than heighten it.

Etc.

Canadas environment minister, David Anderson, recently requested that his colleagues in the cabinet begin driving small, more fuel efficient cars. According to the Guardian of London (March 4, 2002), “His fellow cabinet members ignored him, or muttered about the symbolic importance of being chauffeured around in big (meaning prestigious) cars.”

“The Liberal government talks the talk, but will not drive the drive,” said acting Canadian Alliance leader John Reynolds in the House of Commons. “How can the prime minister or the minister of the environment expect Canadians to sacrifice so much for the sake of Kyoto when his own ministers will not even trade their taxpayer-funded cars for environmentally-friendly vehicles?”

A new study appearing in Physica A (302: 2001), tests the accuracy of climate models and finds them lacking. The problem, say the authors, is that the models do not adequately take into account persistence in the climate system.

“The persistence of short term weather states is a well-known phenomenon: there is a strong tendency for subsequent days to remain similar, a warm day is more likely to be followed by a warm day than a cold day and vice versa,” say the authors. They also note that persistence can occur at time scales of several weeks due to stable high pressure systems that remain stable for long periods of time.

The authors also note that, “There have been also indications that weather persistence exists over many months or seasons, between successive years, and even over several decades. Such persistence is usually associated with slowly varying external (boundary) forcing such as sea surface temperatures and anomaly patterns.”

This issue of persistence is another reason why “separating the anthropogenic forcing from the natural variability of the atmosphere may prove to be a major challenge since the anthropogenic signal may project onto and therefore be hidden in the modes of natural climate variability.”

The authors tested several models. “We are interested,” they write, “in the way the models can reproduce the actual data regarding (a) trends and (b) long-range correlations. Of course, we cannot expect the models to reproduce local trends like urban warming or short-term correlation structures. But long-range correlations show characteristic universal features that are actually independent of the local environment around a station. So we can expect that successful models with good prognostic features will be able to reproduce them.”

“It turns out,” according to the study, “that the models considered display wide performance differences and actually fail to reproduce the universal power law behavior of persistence. It seems that the models tend to underestimate persistence while overestimating trends, and this fact may imply that the models exaggerate the expected global warming of the atmosphere.”

Etc.

Al Kamen in his “In the Loop” column in the February 15 Washington Post: “The Bush White House excels at keeping secrets from the press, opponents, and, sometimes, even friends, judging from a somewhat testy exchange Wednesday evening when White House Council on Environmental Quality aides and others briefed a dozen or so senior GOP congressional staff members on the administrations new environmental package.

“The Hill folks protested that they had not been consulted about the package beforehand. When the White House disagreed, one Hill aide apparently asked for a show of hands from those whod been consulted. None went up, were told. Then talking points were distributed. Bushs goal of reducing our greenhouse gas intensity by _____ will reduce overall U.S. emission by _____ million metric tons by 2012, one point said, calling it an extremely ambitious, yet realistic goal.

“Numbers would help, the Hill team said. After some reluctance, the numbers were supplied. Its like the Wheel of Fortune: you can buy a vowel, you can buy a number.”

Studies Find More Model Weaknesses

Two studies appearing in the February 1 issue of Science give further evidence that climate models are still wholly inadequate to predict future climate change. Using satellite data from the last two decades, a team of researchers led by Bruce A. Wielicki with NASAs Langley Research Center found that, “The top-of-atmosphere (TOA) tropical radiative energy budget is much more dynamic and variable than previously thought.”

The study explains that, “Earths climate system is driven by a radiative energy balance between the solar or shortwave radiation absorbed by Earth and the thermal infrared or longwave radiation emitted back to space.” For the Earths climate to remain unchanged, this energy budget must equal zero. “The TOA radiation budget,” says the study, “is crucial in determining climate variability and feedbacks.” It also provides a rigorous test of the ability of climate models to represent the atmospheres physical processes.

The data show that there was a drop in longwave radiation of about 2 W/m2 (watts per square meter) from the late 1970s to the mid 1980s followed by a rise of about 4 W/m2 from the mid 1980s to the late 1990s. “Because radiative forcings of 1 W/m2 or less are important for climate change prediction, natural variability of 4 W/m2 in the longwave part of the tropical radiation budget is considered a major change.”

The researchers argue that this is not likely due to global warming since, “The flux changes are far too large to be explained by the small surface and atmosphere warming over this time period, which will tend to be offset by increased CO2 and water vapor greenhouse gas trapping.”

More importantly, however, “These changes are sufficiently large that, in principle, they should be seen in climate model predictions.” The researchers tested five different models, including the well known Hadley Centre and National Center for Atmospheric Research models. They found that “There is remarkably little variation in the tropical mean fluxes from the models when compared to the data.”

The other study attempts to answer the question of whether the changes observed in the satellite data in the Earths radiative balance over the last two decades are the result of natural variability or manmade global warming. The researchers, Junye Chen, Barbara E. Carlson, and Anthony D. Del Genio, with NASAs Goddard Institute for Space Studies, found that the “Earth has been radiating more heat and reflecting less sunlight in the region from 30 degrees S to 30 degrees N over the past decade, the net result being more energy leaving the tropics.”

This change is due to a strengthening of two different tropical circulations known as the Hadley cell and the Walker cell. “Equatorial convective regions,” say the researchers, “have intensified the upward motion and moistened, while both the equatorial and subtropical subsidence regions have become drier and less cloudy.”

So whats the upshot? “The possibility that lapse rates were decreasing instead [of increasing] before 1980 suggests that the observed intensification of the Hadley-Walker cell may be due to natural variability on decadal or longer time scales rather than to a forced climate change.”

No Global Warming in Alaska

In 2001, the U.S. National Assessment on climate change concluded that Alaska would warm between 5 and 18 degrees Fahrenheit by 2100. It further claimed that Alaska has already experienced an average “4 degrees F warming since the 1950s.”

This claim is highly misleading, according to Sallie Baliunas and Willie Soon of the Harvard-Smithsonian Center for Astrophysics. In an article appearing on Tech Central Station (www.techcentralstation.com, January 22, 2002), the two scientists explain that the apparent warming in Alaska is due to an entirely natural phenomenon.

The National Assessment stated, “Much of the recent warming occurred suddenly around 1977, coincident with the most recent of the large-scale Arctic atmosphere and ocean regime shifts.” What the report failed to mention, however, is that the global circulation models it used to make its predictions show a gradual warming due to higher concentrations of carbon dioxide, not sudden jumps.

The cause of the 1977 climate jump was a phenomenon known as the Pacific Decadal Oscillation. As explained by Baliunas and Soon, “The Pacific Ocean temperature changes naturally on multiple time scales. The major pattern in the northern Pacific Ocean is for it to hold at a low average temperature for roughly 20 to 30 years, and then to suddenly shift upward, where it remains for some decades. Then it shifts back down again.”

This is a pattern that has been directly measured for the last 100 years. The pattern has also been observed in temperature data derived from tree rings, and reaches back at least 1,000 years. Moreover, a look at the temperature data in Alaska after 1977 shows that 22 of the 30 locations from which Alaskas temperature is measured have experienced “either no warming or a significant cooling trend.”

Antarctic Cooling Down

A forthcoming study in Nature, that has appeared on its website as an “advance online publication,” has found that the Antarctic has been cooling for some time now (www.nature.com). This contradicts the findings of the climate models upon which the case for global warming is built. They predict that the Earths poles will warm more rapidly than the rest of the Earth.

According to the study, “Climate models generally predict amplified warming in the polar regions, as observed in Antarcticas peninsula region over the second half of the 20^th century.” The new study finds that “Our spatial analysis of Antarctic meteorological data demonstrates a net cooling on the Antarctic continent between 1966 and 2000, particularly during summer and autumn.” The McMurdo Dry Valleys, for example, have cooled about 0.7 degrees Celsius per decade during this period of time.

The authors conclude that, “Continental Antarctic cooling, especially the seasonality of cooling, poses challenges to models of climate, and ecosystem change.”

The research into the continents temperature record was motivated by the unexpected coldness of the summers, according to lead author Peter Doran with the Department of Earth and Environmental Sciences at the University of Illinois. “Two or three years ago when we were waiting for the big summers, we noticed that they didnt come,” said Doran. We were thinking that warm summers were the norm, and we were saying, Its going to get back to normal, but it never did” (Washington Post, January 14, 2002).

Michael Oppenheimer, chief scientist for Environmental Defense isnt buying it, however. “Id be very careful with this,” he told the Washington Post. “My general view has been that theres simply not enough data to make a broad statement about all of Antarctica.”

Of course, lack of data has never stopped Oppenheimer from making “broad” statements about the whole Earth. In November 2000, Environmental Defense press release he stated, for instance, “The 1990s, likely the hottest decade of the past thousand years, capped decades of shrinking glaciers, thinning Arctic ice, intensifying rainstorms, and rising seas,” and that this means that, “The world must end its dependence on fossil fuels that are too dirty and too expensive. Governments must take action now.”

It seems that the climate models have struck out. Strike one: they cant simulate the current climate. Strike two: they predict greater and more rapid warming in the atmosphere than at the surface. The opposite is happening. Strike three: they predict amplified warming at the poles, which are cooling instead.

The Antarctic Ice Sheet is Growing

A new study appearing in Science (January 18, 2002) concludes that the West Antarctic Ice Sheet (WAIS) is thickening, rather than thinning as was previously thought. Earlier studies found that in the Ross Sea Sector, “The grounding line (the point where the ice sheet loses contact with its bed and begins to float) has retreated nearly 1300 km along the western side of the Ross Embayment,” since the last glacial maximum.

This led researchers to predict that the entire WAIS would collapse in 4000 years, implying a sea-level rise of 12.5 to 15 centimeters per century. This was based on a measurement of a loss of ice mass of 20.9 13.7 gigatons per year.

The authors of the new study, Ian Joughin and Slawek Tulaczyk, with the Jet Propulsion Laboratory at the California Institute of Technology, note, “The ice-discharge estimates of earlier studies relied on relatively sparse in situ measurements of ice-flow velocity. For some ice streams theestimates were based on only one or two velocity measurements.”

The new study used satellite remote sensing to get better measurements. Contrary to earlier studies, the authors found “strong evidence for ice-sheet growth (26.8 14.9 gigatons per year).” They conclude, “The overall positive mass balance may signal an end to the Holocene retreat of these ice streams.”

Hansen Downgrades Warming Threat

James Hansen, the director of NASAs Goddard Institute for Space Studies, has published a study in the Proceeding of the National Academy of Sciences (December 18, 2002) that downgrades the magnitude of global warming.

According to his analysis, the growth rate of climate forcing from greenhouse gases peaked in 1980 and has since declined from about 5 watts per square meter (W/m2) per century to about 3 W/m2 per century. When all forcings, both negative and positive, are taken into account total net forcing is about 1.6 1.1 W/m2. The Intergovernmental Panel on Climate Change assumes a 4 W/m2 forcing. As the study notes, “Most climate simulations, as summarized by the IPCC, do not include all of the negative forcings; indeed, if they did, and other forcings were unchanged, little global warming would be obtained.”

Hansen and his co-author Makiko Sato, with Center for Climate Systems Research at the Columbia University Earth Institute, predict that “Global warming at a rate +0.15 0.05 degrees C per decade will occur over the next several decades.” This is what the so-called skeptics have been saying all along.

Hansen and Sato put an interesting twist on their argument, however. They state that “the slowdown was caused mainly by phase-out of CFCs” (chlorofluorocarbons), which are also greenhouse gases, under the Montreal Protocol. The previous claim that sulfate aerosol emissions are masking the warming is no longer satisfactory since that has been cancelled out by the discovery of an equal but opposite forcing from black carbon.

Despite Hansens latest conclusion that the planet will only warm about 1.5 degrees C over the next century, a miniscule amount, he still argues for international cooperation to stop global warming. He calls for a “cooperative, not punitive” program of technology transfer from developed to developing world to reduce emissions.

News from Australia

Opponents of the Kyoto Protocol in Australia are clearly making progress in their campaign to defeat ratification. The Canberra Times (January 10, 2002) recently published an op-ed by Clive Hamilton of the Australia Institute that attacks the Lavoisier Group in vitriolic terms.

The Lavoisier Group provides the principal intellectual and organizational opposition in Australia to Kyoto and was organized by our colleague, N. Ray Evans of Melbourne. Hamilton accuses the Lavoisier Group of painting the UNs global warming negotiations as “an elaborate conspiracy in which hundreds of climate scientists have twisted their results to support the climate change theory in order to protect their research funding.” Sounds plausible to us.

Global warming is apparently normal. Iceberg debris on the floor of the North Atlantic indicates the world has had nine global warmings, followed by nine coolings, in the past 12,000 years. All were apparently caused by a 1500-year cycle in the intensity of the suns radiation. The iceberg data is strongly confirmed by the solar activity record produced from carbon-14 dating of tree rings and beryllium-10 dating of Greenland ice cores.

Dr. Gerard Bond and a research team at the Lamont-Doherty Earth Observatory in Palisades, New York, painstakingly assembled this new evidence that climate variability is natural and global. It was published online November 16 by the prestigious journal Science.

Bond used Atlantic sediment cores to measure the rocky debris picked up by glaciers as they ground their way across Canada, Greenland and Iceland, dropping to the Atlantic ocean floor when the icebergs melted. Bond and his colleagues found the amount of debris increased sharply every 1500 years as ice surged farther out into a temporarily colder Atlantic.

Glacier expert Richard Alley of Penn State University says The Bond data are sufficiently convincing that [solar variability] is now the leading hypothesis to explain the Medieval warming that occurred in the 11th and 12th centuries and the Little Ice Age that followed it in the 17th century.

Bond notes that the correlation between earth climate (as measured by his iceberg debris data) and solar activity (as measured by carbon-dated tree rings and beryllium-dated ice cores) is statistically very high. However, Bond says hes even more impressed by the close match between the peaks and troughs of the climate and solar records.

David Thomson, a time-series analyst soon to be at Queens University in Kingston, Ontario, says, Their experiment may be good enough even without statistics. For Bond, thats the scientific equivalent of a touchdown pass.

The Bond study severely undercuts the popular theory of global warming, which holds that greenhouse gases from modern autos and factories are causing a dramatic artificial warming of the earths atmosphere. Current global temperatures are not significantly higher than those of the pre-industrial 1930sor the year 1000. The Medieval warming occurred without autos or factories spewing CO 2, and if it was solar-driven had to be global. It was followed by the Little Ice Age which cannot be attributed to any human cause.

The Bond study indicates we will have to adapt to a gradual increase in world temperatures over the next 200 years or so, because humanity is powerless to alter the sun.

Should we fear the warming? The last global warming is also known to the history books as the Medieval Climate Optimum, the finest weather that humanity can remember, notes climatologist Fred Singer. Singer, who heads the Science and Environmental Policy Project, is also an elected Fellow of the Geophysical Society.

He points out that during the Medieval warming, crops were more abundant, due to more rainfall and longer growing seasons. The Vikings pastured cattle in Greenland, now frozen tundra. The polar ice cap did not melt, and sea levels did not rise abnormally. The wild species migrated with the weather changes as theyd always donethe animals rapidly and the plant species slowly. Storms were milder, because the temperature difference between poles and the equator was smaller. (The bad storms came during the icy part of the cycle, around 1800.)

Will human activity aggravate the next warming cycle? Singer says human impact on the climate is dwarfed by natural variability from such factors as solar cycles and volcanic eruptions. He expects the next warming to be mild and useful, with the biggest effects felt on winter nights in northern climates. We may plant more grain in Canada and Russia, for example. Slightly higher temperatures for farmers at the equator will be more than offset by the crop growth benefits of higher CO2 levels from human activity.

The Kyoto Protocol, he warns, would radically raise world energy prices, hurting humanitys ability to adapt without significantly reducing any warming trend. He believes the real problems, for society and most wild species, will come during the harsh storms of the next Ice Age. Fortunately, Singer says, thats apparently several hundred, and perhaps several thousand, years away.

It remains hard to figure out exactly how the sun has mattered to [recent] climate, says Alley, and why it has mattered so much. The changes in the suns activity have been too small to change the earths temperature directly, but ocean currents could have amplified them.

An oscillation in the northern Atlantic Ocean currents had been the leading alternative in scientists minds to a solar cause for global climate change. The Bond study indicates the two are linked, with the sun as the hammer and the ocean as the nail.

Uncertainty Still Reigns

A new paper in Science (January 4, 2001) attempts to quantify uncertainties in the climate system. Due to its vast complexity, it is difficult for scientists to extract the anthropogenic signal from background noise to determine the most likely future scenarios.

The researchers attempted this by running an “intermediate-complexity model” so that they could make hundreds of runs of the climate for the period 1860 to 1995. They then compared their results to actual temperature changes at the surface, upper atmosphere and deep ocean.

They limited themselves to three variables that they could adjust to determine which range of values would lead to the closest match with actual data: climate sensitivity to a change in greenhouse gas concentrations, ocean heat transfer, and the effects of aerosols that offset warming. According to a news article accompanying the study, the researchers adjusted the variables “over a range of values, ran the model under a large number of setting combinations, and then compared the simulated climate trends with the three observed temperature records.”

“By their own concession,” the researchers had “varied success pinning down the key parameters of the climate system.” They especially had difficulty with ocean heat transfer. What they concluded, however, was that there is a 90 percent chance that the temperature would increase from between 1.4 degrees Celsius and 7.7 degrees C with a doubling of CO2 concentrations. The upper end of the range is much higher than the IPCCs range of 4.5 degrees C.

The really surprising finding, however, is that the net effect of aerosols was to reflect a mere 0.30 to 0.95 watts per square meter of solar power back into space as opposed to the IPCCs scenario of zero to 4 watts per square meter.

What this means, but seems to have escaped the studys researchers, is that there are still serious problems with the existing climate models. In the early 1990s, the climate models predicted far more warming than actually occurred.

To solve the problem, climate modelers hypothesized that anthropogenic emissions of sulfate aerosols, primarily from burning coal, were masking the warming that the models said should be occurring due to rising greenhouse gases. By adding aerosols to the equation, modelers were able to get results closer to reality. But if the cooling effect of aerosols is not as large as thought, as found in the study, then the models are still deficient.

2001 Slightly Warmer Than Average

The year 2001 was only slightly warmer than “average,” according to global climate data gathered by NOAA satellites. The composite global temperature for 2001 was 0.06 degrees Celsius (about 0.11 degrees Fahrenheit) warmer than the 20-year (1979-to-1998) average, said Dr. John Christy, a professor at the University of Alabama in Huntsville. Compared to other years, 2001 was the ninth warmest (and the 15th coolest) since satellite instruments started gathering global climate data in 1979.

As part of an ongoing joint project between UAH, NOAA and NASA, Christy and Dr. Roy Spencer, also with UAH, use data gathered by NOAA satellites to get accurate temperature readings for most regions of the Earth, including remote areas for which reliable climate data are not otherwise available.

The satellite instruments look at microwaves emitted by oxygen molecules in the atmosphere. These microwave emissions vary according to temperature, giving precise indications of temperatures over broad regions of the atmosphere (http://unisci.com/).

Etc.

One of the areas of the planet that is supposed to warm most due to greenhouse gas emissions is the coldest regions of Russia. Moreover, most of the warming is supposed to occur in the winter. Well, this winter Russians are having serious doubts about the validity of the global warming hypothesis as temperatures plummet. Central Europe is also experiencing difficulties due to severe winter weather.

Reuters (January 3, 2002) reports the following:

“Plunging temperatures killed 10 people in Moscow overnight into Thursday in a cold spell that even saw snow fall on palm trees along Russia’s sub-tropical Black Sea coast

“Central Europe meanwhile dug its way out of snowdrifts from the worst blizzards in 15 years and road and rail travel remained hazardous. Avalanche warnings were posted in mountain resorts.

“The international aid agency Medecins Sans Frontiers said 250 people had died in the [Russian] capital this winter. News reports said power cuts had left whole districts in the world’s largest country without light or heat, including the coal mining town of Dzhebariki-Khaya in far northern Yakutia, where temperatures were a seasonal minus 40 degrees Celsius.”

For a list of news stories about record winter weather, see www.john-daly.com.