Public Debate FAQs

Is the world in danger of plunging into a new ice age, as in the 2004 movie The Day After Tomorrow?

• No. The scenario presented in The Day After Tomorrowis physically impossible. While research does suggest that the Gulf Stream has switched on and off in the past, causing temperature drops in Europe, oceanographers are convinced that global warming does not present any such danger.

Is the world in severe danger from sea level rise?

• No. Research from Nils-Axel Mörner, professor of paleogeophysics and geodynamics at Stockholm University, demonstrates that current sea levels are within the range of sea level oscillation over the past 300 years, while the satellite data show virtually no rise over the past decade. The IPCC foresees sea-level rise of between 0.1 and 0.9 meters by 2100. The Earth experienced a sea-level rise of 0.2 meters over the past century with no noticeable ill effects.

  Another study relevant to this controversy is Zwally et al. (2005), which examined changes in ice mass "from elevation changes derived from 10.5 years (Greenland) and 9 years (Antarctica) of satellite radar altimetry data from the European Remote-sensing Satellites ERS-1 and -2." The researchers report a net contribution of the three ice sheets to sea level of +0.05 ± 0.03 millimeters per year. CO2Science.Org puts this in perspective: "At the current sea-level-equivalent ice-loss rate of 0.05 millimeters per year, it would take a fullmillennium to raise global sea level by just 5 cm, and it would take fully 20,000 years to raise it a single meter."

Weren’t recent extreme weather events caused by global warming?

• There is no provable link between weather events like Hurricane Katrina and global warming. For example, research by German scientists has demonstrated that the devastating floods in central Europe in 2002 were perfectly normal events when compared against the historical record. Allegations that extreme weather has been more damaging recently do not take into account the fact that mankind is now living and investing resources in more dangerous areas. Moreover, the World Meteorological Organization has acknowledged that increases in the recorded number of extreme weather events may be due to better observation and reporting. A top expert from the IPCC resigned in January 2005 in protest that IPCC science was being misrepresented by claims that last year’s hurricane season was exacerbated by global warming. Most hurricane scientists agree that there is no way that Hurricane Katrina can be blamed on global warming.
• Recent published research casts extreme doubt on the influence of warming on hurricanes. Philip Klotzbach of Colorado State University finds that, "The data indicate a large increasing trend in tropical cyclone intensity and longevity for the North Atlantic basin and a considerable decreasing trend for the Northeast Pacific. All other basins showed small trends, and there has been no significant change in global net tropical cyclone activity. There has been a small increase in global Category 4-5 hurricanes from the period 1986-1995 to the period 1996-2005. Most of this increase is likely due to improved observational technology. These findings indicate that other important factors govern intensity and frequency of tropical cyclones besides SSTs [sea surface temperatures]."

Aren’t the snows of Kilimanjaro disappearing because of global warming?

• That’s not the verdict of scientists who study Mount Kilimanjaro most closely. In "Modern Glacier Retreat on Kilimanjaro as Evidence of Climate Change: Observations and Facts," Kaser et al. "develop a new concept for investigating the retreat of Kilimanjaro’s glaciers, based on the physical understanding of glacier–climate interactions." They say, "The concept considers the peculiarities of the mountain and implies that climatological processes other than air temperature control the ice recession in a direct manner. A drastic drop in atmospheric moisture at the end of the 19th century and the ensuing drier climatic conditions are likely forcing glacier retreat on Kilimanjaro."

Won’t global warming lead to the spread of malaria?

• Climate is not a significant factor in the recent growth of vector-borne diseases such as malaria. Most experts on this subject agree that malaria is more closely correlated with other factors; deforestation, migration of lowland people (higher immunities, yet they bring disease with them), construction of roads and dams, and the proliferation of pools and ditches are much more important in predicting future spread of these diseases.

Didn’t the U.S. Department of Defense conclude global warming poses a national security threat?

• The Pentagon is not convinced that global warming represents a major security threat to the United States. The "secret paper" that garnered much publicity in Europe was a self-admitted speculative exercise that went beyond the bounds of measured research and had been released to the press long before the sensationalist stories surfaced in Europe. Nor did the paper recommend "immediate action" beyond better climate modeling.

Haven’t recent climate models found that global warming will be much worse than previously thought?

• The news that Oxford University has found that temperatures may increase by up to 11°C severely misrepresents the scientific findings. According to the actual scientific paper, the frequency distribution of the results suggests that the lower end of temperature rises, in the 2°C to 4°C range, is the most likely.

Haven’t the National Academies of all the major industrial countries agreed that global warming is a serious threat?

• Claims have been made that the scientific consensus is represented by a statement drafted by the Royal Society of London and signed by the national scientific academies of the G8 countries plus those of India, Brazil, and China. But such claims ignore the politicized nature of the statement. The climate change committee of the Russian Academy of Sciences later said that its president should not have signed the statement, while the use to which it was put was condemned by the outgoing president of the U.S. National Academy of Sciences, Bruce Alberts, who called the Royal Society’s presentation of the statement "quite misleading."

Aren’t polar bears drowning because of melting ice?

• These claims are overblown. A leading Canadian polar bear biologist wrote recently, "Climate change is having an effect on the west Hudson population of polar bears, but really, there is no need to panic. Of the 13 populations of polar bears in Canada, 11 are stable or increasing in number. They are not going extinct, or even appear to be affected at present."

Isn’t there a scientific consensus such that one researcher found no disagreement about global warming in the literature?

• The research by Naomi Orsekes published in the journal Science in December 2004 was flawed. She studied about 1,000 scientific abstracts, but admitted to a sympathetic journalist that she made a major mistake in her search terms. In fact, she should have reviewed about 12,000 abstracts. Even taking her sample, another researcher who tried to replicate her study came to quite different conclusions. In addition, the most recent survey of climate scientists by Dennis Bray and Hans von Storch, following the same methodology as a published study from 1996, found that while there had been a move towards acceptance of anthropogenic global warming, only 9.4 percent of respondents "strongly agree" that climate change is mostly the result of anthropogenic sources. A similar proportion "strongly disagree." Furthermore, only 22.8 percent of respondents "strongly agree" that the IPCC reports accurately reflect a consensus within climate science.

There is scientific agreement that the world has warmed and that man is at least partly responsible for the warming—though there is no consensus on the precise extent of man’s effect on the climate. There is ongoing scientific debate over the parameters used by the computer models that project future climatic conditions. We cannot be certain whether the world will warm significantly and we do not know how damaging—if at all—even significant warming will be.

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