Like any good science fiction novel or movie, global warming starts from a reasonable premise, and then carries it to an extreme and starts looking at the possible effects on our heroes--which means us, in this case. The reasonable premise--that increased concentrations of CO2 will cause more heat to be trapped in the atmosphere--has been around for a century. Claims of 20 foot rises in sea level or Greenland ice sheets melting, or Antarctica becoming the only habitable place on the Earth are more recent, more foolish and are now being quickly exploded as the scare stories they are.
If I do this right, at the end you should be convinced of two things--first, that a lot of people are trying to scare you to advance a political agenda. Second, and don't forget this, that global warming is not a crazy hallucination--it is an issue at about the same level as many other issues we are addressing today, which means we can't ignore it, but we don't have to let it panic us. It will certainly take more than one article, so consider this Part 1 of umpteen parts.
One of the most popular images thrown at us by global warming alarmists is sea level rise due to global warming. The sea level has risen since the end of the Ice Age, partly because the Ice melted and partly because when the oceans heat up they expand. But it's only in the past few years that hysterics have been saying the Greenland ice cover would melt quickly, as would the Antarctic, pushing sea levels up drastically and catastrophically.
A summary of recent research can be found
here. It comes from an aggregator website called Icecap, which infuriates many global warming activists, as it often publishes some skeptics that are more on the fringe (there are fringe and even lunatic skeptics, just as there are fringe and lunatic alarmists--caveat lettore. They even hijacked one of my articles once, so I guess you can say I admire their taste, if not their tactics). Below are some excerpts from this summary:
"The described changes in Greenland are not at all unprecedented nor are they are described. Many peer review papers support interaction with the Atlantic multidecadal cycles and other factors not greenhouse warming are the real drivers.
Changes to temperature and ice happen predictably every 60 years or so and is in fact entirely natural, related to multidecadal ocean cycles and possibly recently accentuated by major undersea volcanism and the invasion of tundra shrubs and deposition of soot from Asia.
Records of arctic ice cover extent start in 1979. Multidecadal cyclical warming was observed before in the 1800s and middle 1900s long before the industrial revolution. Also there is more recent evidence showing the idea of lubrication by melt water accelerating loss of glacial or icecap ice is not valid.
Other scientists have confirmed that interannual variability is very large, driven mainly by variability in summer melting and sudden glacier accelerations. Consequently, the short time interval covered by instrumental data is of concern in separating fluctuations from trends. But in a paper published in Science in February 2007, Dr. Ian Howat of the University of Washington reports that two of the largest glaciers have suddenly slowed, bringing the rate of melting last year down to near the previous rate. At one glacier, Kangerdlugssuaq, "average thinning over the glacier during the summer of 2006 declined to near zero, with some apparent thickening in areas on the main trunk."
Dr. Howat in a follow-up interview with the New York Times went on to add, "Greenland was about as warm or warmer in the 1930's and 40's, and many of the glaciers were smaller than they are now. This was a period of rapid glacier shrinkage world-wide, followed by at least partial re-expansion during a colder period from the 1950's to the 1980's. Of course, we don't know very much about how the glacier dynamics changed then because we didn't have satellites to observe it. However, it does suggest that large variations in ice sheet dynamics can occur from natural climate variability.”
Thomas, et al. (2000) showed great variance in mass balance of the Greenland ice sheet with highly variable thickening and thinning depending on location. This February (2008) during a bitter cold winter, Denmark's Meteorological Institute stated that the ice between Canada and southwest Greenland reached its greatest extent in 15 years.
Temperatures were warmer in the 1930s and 1940s in Greenland. They cooled back to the levels of the 1880s by the 1980s and 1990s. In a GRL paper in 2003, Hanna and Cappelen showed a significant cooling trend for eight stations in coastal southern Greenland from 1958 to 2001 (-1.29ºC for the 44 years). The temperature trend represented a strong negative correlation with increasing CO2 levels.
On the subject of sea level rise, Roger Pielke's son, well, Roger Jr., also a scientist involved in climate studies, points us to a
review of published literature indicating that predictions of global warming's effects on sea level rise say it will be one meter. These predictions come from scientists who believe in global warming, believe we should act against it, and are experts in the field.
One meter is significant. But it ain't 20 feet.
Source Link:
examiner.com