By David L. Brown
What is it about “climate change” that global warming deniers don’t understand? There is a new outburst of claims that the Earth is cooling, not warming, thus proving that greenhouse gas from human action is a chimera and should be ignored. The basis for these claims appear to be of the sort that reveal complete misunderstanding of just how complicated the issues are. In fact, they follow the pattern of “there was an unusually cold winter in (fill in place), therefore global warming is false. in particular, heavy winter storms and snowfall in large areas of Asia are being invoked, along with the fact that the past winter was relatively mild in much of the U.S.
The people who make these and similar claims seem unaware that global warming does not occur as a general, overall increase in temperature. If that were the case, the approximate 1 to 2 degree C. increase in global temperatures that is taking place would perhaps have a modest effect on the planet. Even a worst-case scenario increase of up to 4, 5 or even 6 degrees might not be too hard to take … if the increase were to be evenly spread out.
But that is not the case, nor did any reputable climate scientist ever imply that it is. In fact, the changes that are taking place are causing weather patterns to change in regional ways. For example, the far North has warmed far more than other areas of the globe, with the resulting decline of the Arctic sea ice and melting tundra. As more open water appears during Summer with its 24 hours of Midnight Sun, the Arctic will grow even warmer.
Meanwhile, other places are bound to become cooler. We have heard of the possibility that warming Arctic waters could stall or even reverse the Atlantic conveyor that carries warm tropical water to heat Western Europe and Scandinavia. Those regions are as far north of the equator as Siberia, and with a reversal of the Atlantic warming they might well enter into a new era of cold, even ice age-like conditions.
Global warming deniers leap on facts like that as evidence against global warming, failing to realize the regional climate change would be a direct result of that very global warming trend that they are denying.
Severe winter conditions in China and other places are quickly pointed out as evidence of global cooling. And yet, the facts remain that the planet is indeed warming, on an average, overall basis.
Yes, some places did experience a cold winter … but look at these recently released statistics from the National Oceanic and Atmospheric Administration (NOAA) for the most recent month of March, 2008, as reported here on the ScienceDaily web site:
- The average global land temperature last month was the warmest on record, 3.3 degrees F. above the 20th Century mean temperature. Ocean temperatures were 13th warmest due to cooling by the La Nina cycle in the Pacific, but total global surface temperature for both sea and land was the second highest since records began being kept in 1880.
- Also during March, temperatures more than 8 degrees F. above average covered much of Asia. In the Eurasian continent, following the greatest January snow coverage on record the unusually high temperatures resulted in rapid snow melt resulting in March snow cover that was the lowest on record.
Deniers pointed to the heavy snow pack in Asia and Europe as evidence against global warming, but one might interpret this as climate change instead. And how do they explain the rapid meltdown that turned the January snow into a March runoff? Not by invoking global cooling, surely.
Also reported this week was the fact that the North American jet streams have been migrating northward for some time now. This is another marker of climate change. Jet streams influence weather patterns in significant ways.
Meanwhile, look at this NOAA illustration of March precipitation patterns in the U.S.
As can clearly be seen, a broad swath from Oklahoma to Vermont experienced rainfall that was “much above normal,” while California, Arizona and New Mexico saw precipitation “much below normal.” Relatively few states appear in white, denoting normal conditions. The overall picture is one of deviation above and below what has been considered normal from past records, offering further evidence that the effects of global warming are not smoothly distributed but may result in changing weather patterns and more extremes.
There is an old chestnut that says if you were to stand with one foot in a bucket of cold water and the other foot in a bucket of hot water, on the average you would be comfortable. That may be true for a given point in time. But if the average is rising over time, i.e. the water in both buckets is growing warmer, that trend should be taken seriously.
Taking another example, it is said that if you place a frog into a pan of cool water and begin to heat it, the frog will not jump out because it senses only gradual change and is not alarmed. The ultimate result, of course, is quite detrimental to the frog’s future plans. Thus, too, for climate change deniers.