A series of recent studies shows that the polar ice caps, which should be shrinking if dire global warming theories are correct, are maintaining their mass and in fact growing slightly. The studies suggest satellite temperature readings, which indicate no global warming of the lower atmosphere, are more reliable than surface temperature readings, taken by humans under varying conditions, that had indicated a slow, gradual warming.
A study published in the December 3, 1999 issue of Science magazine, authored by Ola Johannessen, Elena Shalena, and Martin Miles, reported Arctic sea ice had declined by 14 percent from 1978 through 1998. In a related story, columnist Richard Kerr pondered “Will the Arctic Ocean lose all its ice?” The mainstream press ran with the story, giving dire warnings that global warming was upon us.
However, CO2 Science Magazine later noted that in the Johannessen study, “essentially all of the drop . . . occurs rather abruptly over a single period of not more than three years (87/88-90/91) and possibly only one year (89/90-90/91). Furthermore, it could be argued from their data that from 1990/91 onward, sea ice area in the Arctic may have actually increased.”
More recent studies of the polar ice caps verify CO2 Science Magazine’s skepticism, and show the polar ice caps are holding their own and actually growing slightly.
Antarctic sea ice edge expanding
A study published in the American Meteorological Society’s Journal of Climate (Yuan, X. and Martinson, D.G., “Antarctic sea ice extent variability and its global connectivity,” Volume 13: 1697-1717 (2000)) demonstrated the Antarctic polar ice cap has been expanding. According to the study, 18 years of satellite data indicate the mean Antarctic sea ice edge has expanded by 0.011 degrees of latitude toward the equator each year.
A later study, also published in Journal of Climate (Watkins, A.B. and Simmonds, I., “Current trends in Antarctic sea ice: The 1990s impact on a short climatology,” Volume 13: 4441-4451 (2000)) reached a similar conclusion. The study reported significant increases in Antarctic sea ice between 1987 and 1996. The study further indicated the 1990s exhibited increases in the length of the sea-ice season.
Arctic ice thickening, expanding
A study published in Geophysical Research Letters (Winsor, P., “Arctic sea ice thickness remained constant during the 1990s,” Volume 28: 1039-1041 (2001)) found the same to be true in the Arctic. The study concluded, “mean ice thickness has remained on a near-constant level around the North Pole from 1986-1997.” Moreover, the study noted data from six different submarine cruises under the Arctic sea ice showed little variability and a “slight increasing trend” in the 1990s.
Just off the Arctic polar ice cap, ice coverage in Greenland was also shown to be steady and likely increasing. A study in Journal of Geophysical Research (Comiso, J.C., Wadhams, P., Pedersen, L.T. and Gersten, R.A., Volume 106: 9093-9116 (2001)) concluded that, annual variances notwithstanding, the Odden ice tongue in Greenland exhibited no statistically significant change from 1979 to 1998. Moreover, proxy reconstruction of the ice tongue utilizing air temperature data indicated the ice covers a greater area today than it did several decades ago.
Viewed as a whole, the new ice cap studies indicate no global warming has occurred in recent decades, at least not in high latitudes. These findings also offer an important insight into one of the more significant controversies surrounding global warming theory.
Surface vs. satellite readings
Surface temperature readings taken by humans indicate the Earth has warmed by approximately 1 degree Fahrenheit over the past 100 years. This warming is certainly not much, but it is often cited as evidence that global warming is occurring, even if it is merely in its initial stages.
However, precise satellite readings of the lower atmosphere (a region that is supposed to immediately reflect any global warming) have shown no warming since readings were begun more than 20 years ago.
“We have seen no sign of man-induced global warming at all. The computer models used in U.N. studies say the first area to heat under the ‘greenhouse gas effect’ should be the lower atmosphere, known as the troposphere. Highly accurate, carefully checked satellite data have shown absolutely no warming,” explained Tom Randall of the National Center for Public Policy Research.
Global warming skeptics have pointed out that most of the surface temperature readings indicating a warming have been taken in underdeveloped nations, where reliability and quality-control are questionable. In developed nations such as the United States, by contrast, the readings tend to show no warming. Moreover, skeptics note, surface temperature readings are influenced by artificial warming associated with growing urbanization, which creates artificial heat islands around temperature reading stations.
“While the greenhouse gases, especially CO2, have grown in the last 50 years, the correlation with a warming of the world’s climate is weak and far from being generally accepted by the scientific community,” James L. Johnston, a member of The Heartland Institute’s Board of Directors, observed in the August 4 Chicago Tribune.
Global warming proponents, on the other hand, now counter that warming, despite prior consensus to the contrary, might occur in the lower atmosphere only after a general warming of the Earth’s surface.
Models shown to be inaccurate . . . again
The recent polar ice studies, which measured surface rather than atmospheric temperature trends (and which were far removed from the effects of urban heat islands and questionable third-world temperature readings), lend weight to the argument that satellite readings, not surface monitoring stations, are correct.
“In considering all of the above results, it is likely that the global extent of sea ice is on the rise. Such observational evidence flies in the face of model predictions of global warming that say climate will change first and to the greatest extent in the Earth’s polar regions,” concludes CO2 Science Magazine.
CO2 Science suggests that self-regulating mechanisms, such as clouds, enable the Earth to keep a relatively steady climate despite the changes in CO2 concentration that have been a regular part of Earth’s history.
Viewing the new data in conjunction with other studies that properly filter out the imperfections of human-collected temperature readings, CO2 Science concludes, “There has been no global warming for the past 75 years.”