One of the great fears generated by global warming is that the ocean is about to rise and swallow our coasts. These concerns have been heightened by the substantial uptick in Atlantic hurricane activity that began in 1995. The frequency of really strong storms striking the U.S now resembles what it was in the 1940s and 50s, which few people (aging climatologists excepted) remember.
Those arguing that global warming is an overblown issue have been claiming for years that “consensus” forecasts of sea-level are equally overwrought. The United Nations’ Intergovernmental Panel on Climate Change predicts a global average rise of from 3.5 to 34 inches by 2100, with a central estimate of 19 inches. Depending upon how you slice or dice the data, the last century saw maybe six inches.
Critics have long argued that these changes require a substantial net melting of some combination of the world’s two largest masses of land-based ice, Antarctica and
Over 15 years ago, John Sansom published a paper in Journal of Climate that showed no net warming of
At the same time, a deluge of stories appeared, paradoxically, about Antarctic warming. These studies concentrated on the tip of the Antarctic Peninsula, the narrow strip of land that juts out towards
Warmer water evaporates more moisture. The colder the land surface over which that moisture passes, the more it snows. So,
Almost all of the gain in
The temperature situation in Greenland is more mixed than in
The only other masses of ice on the planet that can contribute to sea level rise are the non-polar glaciers, but they are very few and far between. The biggest is the Himalayan ice cap, but it’s so high that a substantial portion will always remain. Most of the rest are teeny objects tucked away in high elevation nooks and crannies, like our
If all these glaciers melted completely — including the Himalayan ice cap — sea level could rise no more than five to seven inches, because there’s just not that much mass of ice, compared to Antarctica and Greenland.
It is simply impossible for the scientific community to ignore what is going on, even as prone to exaggeration of threats as it has grown to be. The planet is warming at the low end of projections.
Meanwhile,
It is inevitable that one of tomorrow’s headlines will be that scientists have dramatically scaled back their projections of sea level rise associated with global warming. Had they paid attention to data (and snow) that began accumulating as long as fifteen years ago, they would have never made such outlandish forecasts to begin with.
This article first appeared in Tech Central Station.
References:
Doran, P.T., et al., 2002. Antarctic climate cooling and terrestrial ecosystem response. Nature, 415, 517-520.
Johannessen, O.M., et al., 2005. Recent Ice-Sheet Growth in the Interior of
Krabill, W., et al., 2005.
Sansom, J., 1989. Antarctic Surface Temperature Time Series. Journal of Climate, 2, 1164-1172.