Testimony: Science and Global Warming: What Do We Know?

Published March 8, 2007

Presentation Delivered
to the
Minnesota Climate Science Symposium

March 8, 2007

Thank you for the kind introduction, Senator Jungbauer. It truly is an honor and a privilege to speak with you here today. Dr. Patrick Michaels, who is unquestionably one of the world’s foremost climate scientists, has just provided us with the most up-to-date global warming science. That being the case, I would like to spend my time sharing with you what is not the current state of global warming science.

What I mean by this is that wholly implausible scare scenarios are routinely disseminated to and through the media, even though they are contradicted by real-world scientific evidence. Some of these scientifically unsubstantiated assertions appear in former vice president Al Gore’s movie “An Inconvenient Truth.”

Sadly, although Mr. Gore’s film presents slick images and catchy computer graphics, science and truth have been sacrificed to make a case for immediate action. Gore’s cinematic assertions are repeated as “truth” by a largely sympathetic media that seldom bothers to do their own research or mention contradictory scientific facts. I would like to spend my time today presenting a less biased and more scientifically cautious review of the scientific evidence.

I would like to make one note before I begin. My references to Al Gore’s movie are in no way intended to be partisan or personal. California Republican Governor Arnold Schwarzenegger and Arizona Republican Senator John McCain are also been prominent global warming alarmists. Conversely, many Democrats are quite skeptical of global warming alarmism. Indeed, House Speaker Nancy Pelosi’s attempt to make an end run around Commerce Committee Chairman John Dingell, a Michigan Democrat, in the U.S. House speaks to the bipartisanship on both sides of the issue. I will be repeatedly referencing Al Gore’s “An Inconvenient Truth” today solely because it is the source that most of today’s audience will be familiar with because it has received the most accolades from global warming alarmists.

Scientific ‘Consensus’

Let us begin by examining the alleged “scientific consensus” regarding global warming. Al Gore and global warming alarmists frequently cite what is known as the Oreskes study to assert there is absolutely no legitimate scientific dissent to alarmist global warming theory. This “study” is, to use an unscientific term, a joke.

Unlike Dr. Michaels, Naomi Oreskes is not a climatologist. She is a professor specializing in “gender studies” at the University of California at San Diego. She performed the functional equivalent of a Google search in which she searched a database of scientific journals for the keywords “climate change” and came up with 928 results. She then scanned the abstracts of the articles and checked to see if any of them explicitly refuted the assertion that humans are likely to be responsible for most of the observed warming of the last 50 years. She said that none of the abstracts explicitly refuted the assertion. This, she asserted, proved there is no real scientific disagreement with alarmist global warming theory.

Oreskes’ assertion is severely flawed for several reasons:

First, most of the abstracts neither endorsed nor rejected a particular theory regarding global warming. Indeed, most did not even mention the extent of potential human influence on the Earth’s climate. Some of the abstracts mentioned climate change only in passing and were focused on other topics. Others took no position on the causes of our recent moderate warming and, assuming for the sake of argument that global warming may continue to occur, merely discussed tangential issues. What remained was only a small minority of abstracts endorsing the alarmist position.

Second, even if we discuss only the very small number of abstracts that endorsed the alarmist view, this is hardly a trustworthy indicator of current scientific thought. Journal editors are naturally biased toward publishing studies that suggest the existence of a major problem or new discovery. Articles saying “no correlation was found” imply, in effect, “no news here,” and sell few copies and attract little attention, whereas articles saying, “here is a new and scary way we are all going to die” sell more copies.

Third, the Oreskes “Google search” was very imprecise. We all know that a primary source of information is better than a secondary source. A secondary source is better than a tertiary source. Oreskes merely performed a self-selected Google search of articles written primarily by non-climatologists, that were already subjectively filtered by editors and publishers.

If we had no primary or secondary sources regarding the current scientific thought on global warming, then perhaps the Oreskes study would hold a small amount of merit. However, far better sources of scientific opinion are available.

One, the Oregon Institute of Science and Medicine, maintains a Web site summarizing the evidence contradicting alarmist global warming theory. Attached to the summary is a petition in which more than 17,000 scientists have expressed their strong disagreement with alarmist global warming theory. Let me repeat, more than 17,000 scientists not only disagree with alarmist global warming theory, but feel so strongly about it that they made the effort to find the Oregon Institute of Science and Medicine petition and take the affirmative step of signing the petition.

Two, in 1996 and 2003, scientists at Germany’s Institute of Coastal Research sent out a questionnaire to more than 1,000 climate scientists around the world seeking their views on global warming. More than 500 climate scientists returned the questionnaire each time. The survey found that more climate scientists “strongly disagree” than “strongly agree” that climate change is mostly the result of human influence. Regarding this and all other global warming issues addressed in the questionnaire, scientists were sharply split on the causes and likely effects of recent warming temperatures. [For more about these surveys, see “What Climate Scientists Really Say about Global Warming,” Heartland Policy Study No. 111, February 2007, http://www.heartland.org/Article.cfm?artId=20732.]

Three, the National Registry of Environmental Professionals in November 2006 released results from a survey of nearly 800 environmental scientists and environmental professionals in the U.S. regarding global warming. Forty-one percent of the respondents disagreed that the planet’s recent warmth “can be, in large part, attributed to human activity.” Forty-seven percent disagreed that international agreements such as the Kyoto Protocol provide a solid framework for combating global climate change. Seventy-one percent disagreed that recent hurricane activity is significantly attributable to human activity.

These surveys directly contradict the assertion–which appears in “An Inconvenient Truth” and is repeated by many other alarmists–that there is no real scientific debate about global warming.

With that misperception cleared up, I would now like to discuss some of the specific assertions made by global warming alarmists.

Glaciers in the Himalayas

Al Gore gives very prominent attention in his movie to an alleged shrinkage of glaciers in the Himalayan Mountains. Gore says the glaciers are shrinking and global warming is to blame. Worse, Gore says, the shrinking of glaciers threatens the water supply for literally billions of people.

Al Gore is not alone among global warming alarmists in making such a claim. On March 14, 2005, just a few months before Gore filmed “An Inconvenient Truth,” the World Wildlife Fund made similar assertions. Let me quote from their March 14, 2005 press release: “Himalayan glaciers are among the fastest retreating glaciers globally due to the effects of global warming, and this will eventually result in water shortages for hundreds of millions of people who rely on glacier-dependent rivers in China, India, and Nepal.”

The World Wildlife Fund press release continues, “water level in rivers will decline, meaning massive economic and environmental problems for people in western China, Nepal, and northern India.”

But consider this: Insurance Digest reported on March 13, 2005–exactly one day before the World Wildlife Fund assertions, and just a few short months before Gore made his assertions–that “There’s good news for the geologists and the environmental scientists who have been craving to assuage their anxieties over shrinking of glaciers and drying up of snow-fed rivers. Heavy snows in the higher regions of Himachal Pradesh this year have rejuvenated them all.

“The snowfall has given a fresh lease of life to both perennial and seasonal glaciers in the region. The region has received its heaviest snowfall in over two decades this year.”

The article continues, “The heavy snowfall is also fortuitous for the rivers, especially snow-fed ones which will have abundant water during summers when the snow melts, which in turn shall boost [hydro]-power generation.”

Need more evidence? The September 2006 issue of the American Meteorological Society’s Journal of Climate reported:

“Glaciers are growing in the Himalayan Mountains, confounding global warming alarmists who have recently claimed the glaciers were shrinking and that global warming was to blame.

“A new study of the Karakoram, Hindu Kush, and Western Himalaya mountain ranges by researchers at England’s Newcastle University shows consistent recent growth among the region’s glaciers.

“Researchers found cooler summers are failing to melt winter snows, which are themselves becoming more frequent, resulting in advancing ice sheets.”

One would think such news would generate a mea culpa from Al Gore and global warming alarmists. One would think the news media would report the good news as quickly and as vociferously as they reported the scare scenarios.

But actually, the good news about glaciers has merely led to a ludicrous flip-flop. The September 11, 2006 issue of National Geographic reported, apparently without irony, “Some glaciers in Pakistan’s Upper Indus River Basin appear to be growing, and a new study suggests that global warming is the cause.”

And just as the media had previously reported shrinking glaciers would threaten the water supplies of tens of millions of people, they now claim the water supplies of millions of people are threatened by growing glaciers.

In an August 24, 2006 article titled “Global warming boost to glaciers,” BBC News warned, “the findings are significant, because temperature and rain and snow trends in the area impact on water availability for more than 50 million Pakistanis.”


Some of the most striking scenes in Al Gore’s movie are the before and after photographs of Africa’s Mt. Kilimanjaro. Gore shows a photograph of the Kilimanjaro alpine glacier in 1970, and then shows a photograph of the same alpine glacier in 2005. The more recent photo shows a smaller snow cap than was previously the case. This, Gore tells us, is proof of global warming. However, the science tells us something different.

From 1953 through 1976, the globe was cooling, and yet Kilimanjaro lost 21 percent of its original snow cover. Moreover, from 1979 to 2000, satellite data measured additional cooling in the Kilimanjaro region, and yet Kilimanjaro’s glacier continued to shrink.

So how can Kilimanjaro’s snow cap be shrinking during cooling temperatures?

As far back as 2003, science had the answer. The following is a quote from the November 23, 2003 issue of Nature magazine:

“Although it’s tempting to blame the ice loss on global warming, researchers think that deforestation of the mountain’s foothills is the more likely culprit. Without the forests’ humidity, previously moisture-laden winds blew dry. No longer replenished with water, the ice is evaporating in the strong equatorial sunshine.”

Nature magazine’s analysis has been confirmed by such publications as the International Journal of Climatology, the Journal of Geophysical Research, and the Bulletin of the American Meteorological Society. Scientists have known for many years now that Kilimanjaro’s snow cap is retreating due to drier air linked to local land use rather than to global warming. But that does not stop Al Gore and other global warming alarmists from pointing the finger at global warming.

Glacier National Park

Al Gore similarly claims that temperatures are warming so fast at Glacier National Park that “within 15 years, this will be The Park Formerly Known as Glacier.” While we can all come up with a cute little sound byte to say anything we want, even something that is not true, temperature records for the Glacier National Park region do not lie.

While Gore shows successive photos of shrinking glaciers in Glacier National Park from 1988 to 1998, temperature readings in the nearby community of Telluride show temperatures declined 3 degrees during that time span. Temperature readings in the nearby community of Boulder show a 2 degree decline during that time span, and a decline of 6 degrees from 1953 to 1998.

Just as science does not support the Himalayan or Mt. Kilimanjaro false alarms, neither does science support the Glacier National Park false alarm. Perhaps the glaciers are receding, but if this is so, human-induced global warming is not to blame.


How about tornadoes? Al Gore shows very scary pictures of tornadoes bearing down on farms and townships, and then asserts that global warming is causing a surge in tornado activity. Once again, Al Gore and global warming alarmists are playing fast and loose with the science. How do we know this is true? Just last month [February 2007] the United Nations Intergovernmental Panel on Climate Change reported, “There is insufficient evidence to determine whether trends exist in small-scale phenomena such as tornadoes.”

Indeed, just last week an unusually strong and deadly outbreak of tornadoes across the Southeastern U.S. was linked by scientists not to global warming, but to abnormally cold winter conditions.


Next, let’s look at hurricanes. Al Gore says global warming is causing more and stronger hurricanes, and implies that Hurricane Katrina would never have happened if not for human activity.

Scientists, however, disagree. The National Oceanic and Atmospheric Administration (NOAA) on November 29, 2005 released a study in response to claims such as those made by Gore. According to NOAA, “NOAA attributes this increased activity to natural occurring cycles in tropical climate patterns near the equator. These cycles, called ‘the tropical multi-decadal signal,’ typically last several decades (20 to 30 years or even longer). As a result, the North Atlantic experiences alternating decades long (20 to 30 year periods or even longer) of above normal or below normal hurricane seasons. NOAA research shows that the tropical multi-decadal signal is causing the increased Atlantic hurricane activity since 1995, and is not related to greenhouse warming.”

Indeed, this is supported by the fact that the number of tropical storms in the Pacific Ocean and Indian Ocean have not increased at all. If global warming were causing a surge in hurricanes, this should be evident around the globe, not just in one small portion of it.

Sahara Desert

How about expanding deserts? Al Gore shows a nifty map in his presentation with catchy graphics indicating the Sahara Desert is expanding, especially in its southern regions. This, we are told, is due to global warming. But is this really true? Once again, the science says “no.”

According to the September 16, 2002 issue of New Scientist magazine, “Africa’s deserts are in ‘spectacular’ retreat.” The article documents how vegetation is reclaiming large expanses of barren land across the entire southern edge of the Sahara desert.

The article continues, “The southern Sahara desert is in retreat, making farming viable again in what were some of the most arid parts of Africa. … Burkina Faso, one of the West African countries devastated by drought and advancing deserts 20 years ago, is growing so much greener that families who fled to wetter coastal regions are starting to go home.” Moreover, this phenomenon of a greening planet is not limited to the southern Sahara desert. A study on variations in northern hemisphere vegetation taken from satellite data from 1981-1999, reported in the Journal of Geophysical Research, found an 8 to 12 percent increase in vegetation across North America and Eurasia. A subsequent comment in the same journal concluded that a concurrent rise in atmospheric CO2 was primarily responsible for the increased vegetation.


Let’s next look at Greenland. Al Gore asserts that the Greenland ice sheet is melting, due to global warming, and this is threatening us with a planet-wide flooding catastrophe. According to Gore, “Because of what’s happening in Greenland right now, the maps of the world will have to be redrawn.”

So exactly what does science say is “happening in Greenland right now?”

In late 2006, researchers at the Danish Meteorological Institute and the Climatic Research Unit at the University of East Anglia (UK) correlated Greenland’s surface temperature readings and ice core data dating back to 1784.

They made a remarkable discovery. The past two decades were the coldest decades for Greenland since the 1910s. Average annual temperatures during the past two decades were colder than in any of the previous six decades. Greenland’s temperatures during the 1980s and 1990s averaged a full 1.5 degrees Celsius lower than average annual temperatures during the 1930s and 1940s.

Moreover, according to a 2005 study in Journal of Glaciology, seven scientists who had analyzed 10 years’ worth of data reported, “the Greenland ice sheet is thinning at the margins and growing inland, with a small overall mass gain.” I repeat, “a small overall mass gain.”

So how is it that Al Gore and global warming alarmists show striking photos of glacier retreat as “evidence” of global warming? Because they only mention the thinning at the edges and conveniently forget to mention the more extensive thickening of the glacier inland.

For the sake of intellectual honesty, I will note that shortly after Gore made his spurious claims, scientific measurements found that Greenland did, for a period of less than a year, have a slightly elevated rate of glacier shrinkage at its edges. Greenland actually began discharging slightly more of its snowcap than it was building. However, just last month scientists reported that the brief hiccup was nothing more than that, a short-term variable that has now ended.

Gulf Stream

Al Gore asserts in his movie that melting snow and ice from Greenland could shut down the oceanic conveyor belt, including the North Atlantic Gulf Stream, and thus trigger a new ice age. This claim merely repeats a long-standing scare scenario presented by global warming alarmists. With alarmists now claiming that global warming will imminently induce the next ice age, it makes one wonder whether global warming alarmists should debate themselves over whether global warming will warm the planet or cool the planet. They certainly should be able to settle on one or the other of the self-contradictory scare scenarios if they wish to have any credibility regarding their assertions.

Nevertheless, let’s look at the Gulf Stream shut-down theory. Even the most cursory look at the evidence shows the shut-down theory has no basis in scientific fact.

Scientists very recently studied the Gulf Stream and discovered no such chance of an imminent shutdown. Reporting on an October 2006 conference of scientists who had studied the Gulf Stream, the November 17, 2006 issue of Science magazine reports, “more than 95 percent of the scientists at the workshop concluded that we have not seen any significant change of the Atlantic circulation to date.”

Similarly, Johan Jungclaus, a German scientist who models ice sheets, reported in the November 7 New Scientist, “Abrupt climate change initiated by the ice sheet melting is not a realistic scenario for the 21st century.”

So here we have yet another global warming scare thoroughly debunked.


Let’s next look at Antarctica. In “An Inconvenient Truth,” Al Gore claims that Antarctica is “a canary in the coal mine” that proves the imminence of a global warming catastrophe. Gore and other global warming alarmists frequently point to dramatic melting of the West Antarctica ice sheet as irrefutable proof of catastrophic global warming. The imminent melting of the Antarctic ice sheet, they claim, will flood the world’s coastlines, leading to unprecedented human misery.

Does the science back up such claims? Once again, the answer is “no.”

In focusing solely on a small portion of West Antarctica, Gore and his fellow global warming alarmists are guilty of cherry-picking a small subset of data that they know is not representative of Antarctica as a whole. While it is true that temperatures are warming and ice is melting in the 10 percent of Antarctica that is the West Antarctic Peninsula, the remaining 90 percent of Antarctica is dramatically cooling and gaining significant ice mass.

On January 14, 2002, Nature magazine reported that Antarctica as a whole has been dramatically cooling for decades. Nature reported that temperatures across the continent have dropped an average of 0.125 degrees Fahrenheit per year, or 1.2 degrees Fahrenheit per decade, since 1978.

“The decline is alarming,” Nature quoted Diana Wall of Colorado State University who compiled the Antarctic data. “These cooling repercussions may have a long-term effect,” said Wall.

More recently, scientists reported in a September 2006 article published in the British journal Philosophical Transactions of the Royal Society A: Mathematical, Physical, and Engineering Sciences, that satellite measurements of the Antarctic ice sheet showed significant growth between 1992 and 2003.

According to the most recent scientific measurements, as reported by Royal Society scientists, “Mass gains from accumulating snow, particularly on the Antarctic Peninsula and within East Antarctica, exceed the ice dynamic loss from West Antarctica.”

Also, the United Nations Intergovernmental Panel on Climate Change, which itself has a record of making overly alarmists predictions, nevertheless just last month stated that for at least the next full century, “the Antarctic ice sheet will remain too cold for widespread surface melting and is expected to gain in mass.”

I repeat, Antarctica, for at least the next full century, “is expected to gain in mass.”

Canary in the coal mine, indeed.

Polar Bears

How about polar bears? In “An Inconvenient Truth,” Al Gore shows images of polar bears apparently stranded at sea on an iceberg. Gore claims polar bears are drowning and global warming is to blame. Indeed, since the release of “An Inconvenient Truth,” environmental activists have persuaded the U.S. government to look into listing polar bears as an endangered species due to feared global warming.

Well, what are the facts? First of all, images of polar bears on icebergs are not pictures of polar bears in distress. Polar bears are capable of swimming 60 to 100 miles without interruption.

Icebergs have been breaking off from the polar ice cap since long before any alleged human influence on our global climate, as the passengers of the Titanic could have attested.

Even so, polar bears are not stranded and fated to death by drowning, regardless of what Al Gore and global warming alarmists would like us to believe. Polar bears can take refuge on such a breakaway iceberg for days and even weeks while still retaining an easy ability to swim back to the ice cap. In fact, scientists tell us that polar bears frequently take refuge on floating icebergs as a means of soaking up some sun and warming their bodies from the ocean’s cold water.

Regardless of what Al Gore and global warming alarmists claim, we know there are more than 20,000 wild polar bears in the world and that their numbers are not in decline. Indeed, polar bears quite easily survived higher temperatures 1,000 years ago during the Medieval Climate Optimum and 2,000 years ago during the Roman Climate Optimum.

Moreover, for the sake of argument, if we were to be concerned about polar bear populations even though they are not in decline, a much more simple solution is readily apparent. In Greenland alone hunters have long been allowed to kill roughly 250 polar bears per year–more than 1 of every 100 wild polar bears alive on the planet.

Unremarkable Warming

Next, let’s look at the nature of our recent warming. Al Gore claims in his movie that recent temperature rise “in recent years is uninterrupted, and it is intensifying.” The real-world data, however, contradict this assertion, as well.

Gore claims 2005 was the hottest year on record, but this is not true. Climate records show 1998 was. The fact is that temperatures have declined since 1998 and we are currently in a decade-long cooling spell. But even so, short-term temperature trends are not as telling as the broader temperature record.

Periods of advancing ice sheets–known as glaciations–each lasting approximately 100,000 years, have dominated the planet’s climate history. Shorter periods of receding ice sheets–known as interglacials–each lasting about 10,000 years, have interrupted the glaciations. For the past 10,000 years we have been in an interglacial period. Historically speaking, our greatest concern right now should be about imminent cooling in the overdue next glaciation, rather than our recent moderate warming.

Regardless, Al Gore in his movie unwittingly illustrates a fly in the ointment of alarmist global warming theory. As a temperature graph presented by Gore shows, during at least the past four interglacials, temperatures were higher than they are today. Let me repeat, during at least the past four interglacials, temperatures were higher than they are today. Ice core measurements from Greenland show temperatures in the past four interglacials ranged from 3 to 6 degrees Celsius warmer than they are today.

To put that in perspective, our recent warming would have to continue for two to four more centuries, without interruption and without mitigation, before we attain the temperatures that one would normally expect in an interglacial warming. As we approach a time when history says we are due for a return of advancing ice sheets, the real question is not “why is the Earth so warm today,” but rather, “why is the Earth so cool today.”

Assertions by Al Gore and others that today’s temperatures are unprecedented are, once again, scientifically wrong.

Carthage, Tennessee

Let me touch on one final assertion made by Al Gore in his movie. Gore shows film footage of a lazy, winding river near his Carthage, Tennessee tobacco farm. He says, “Here on this farm, the patterns are changing –it’s happening very, very quickly.”

Well, maybe things are changing quickly on the Gore tobacco farm, but certainly not in the way Al Gore would lead us to believe. Temperature stations in the nearby communities of Clarksburg, Murfreesboro, and McMinnville, Tennessee all show regional temperatures have actually cooled 3 degrees since 1920. Gore’s assertion that his farm is experiencing the effects of rapidly warming temperatures is as fully contradicted by the science as is virtually every other one of his claims in the movie.

Minnesota Temperatures

Similar data are available for many Minnesota communities. According to temperature data from the United States Historical Climatology Network, from 1930 to the end of the twentieth century, temperatures in Albert Lea have dropped 5 degrees. In Eveleth, temperatures have dropped 4 degrees. In Fosston, temperatures have dropped 2 degrees. In Grand Meadow, temperatures have dropped 4 degrees. In Milan, temperatures have dropped 4 degrees. In Minneapolis, temperatures have dropped 4 degrees. In Montevideo, temperatures have dropped 6 degrees. In Mora, temperatures have dropped 4 degrees. In Morris, temperatures have dropped 3 degrees. In New Ulm, temperatures have dropped 5 degrees. In Park Rapids, temperatures have dropped 4 degrees. In Pipestone, temperatures have dropped 6 degrees. In Roseau, temperatures have dropped 2 degrees. In Two Harbors, temperatures have dropped 4 degrees. In Winnebago, temperatures have dropped 4 degrees. In Zumbrota, temperatures have dropped 5 degrees.


Science repudiates the frightening predictions of Al Gore and other global warming alarmists. What are we left with?

We are left with a recent temperature record that is fairly unremarkable. For the past 30 years, temperatures have moderately warmed. For the 30 years before that, temperatures cooled. For 60 years or so before that–before humans could have had any appreciable effect on global temperatures–the planet warmed. For 600 or so years before that the planet cooled. Prior to that, the planet warmed. In short, rising and falling global temperatures are nothing new.

The net warming that has occurred since the end of the Little Ice Age just over a century ago has brought with it tremendous benefits to human health and our global environment. Growing seasons have lengthened. Crop yields have risen dramatically. Forests around the globe have expanded rapidly. Deserts have receded, and the planet has grown greener. Each of these benefits is directly traceable in large part to a warmer planet with higher atmospheric carbon dioxide.

By contrast, not one of the frightening scare scenarios proclaimed by global warming alarmists has materialized. And science tells us that none is likely to materialize anytime in the near future.

With these facts in mind, Minnesota legislators would be wise to forego asking the citizens of this state to undergo painful economic sacrifice to fight an alleged problem that is far from alarming.

Thank you very much, Senator Jungbauer, for inviting me to speak here today.

James M. Taylor ([email protected]) is The Heartland Institute’s senior fellow for environment policy and managing editor of Environment & Climate News. These remarks were delivered on March 8, 2007 to the Minnesota Climate Science Symposium.