My biggest problem with global warming catastrophists is that the last time global warming occurred (less than a thousand years ago) nothing catastrophic happened. That's not to say, however, that climate change can't have a detrimental effect on a civilization. As a Viking buff, I know that climate change played an important role in Viking history--in their case: global cooling! The cooling climate, in large part, led the Vikings to abandon their colonies in western Greenland and North America.
From proponents of anthropogenic global warming theory, however, one gets the the sense that climate change is usually slow, moving at a geologic pace, and that the current period of global warming is unprecedented. In fact, neither of these propostions are true. There's a great article in the December 2000 issue of Analog Science Fiction and Fact, "Summer's Lease" by J.R. Dunn that puts these misconceptions to rest and suggests that climate change, as an ongoing phenonenon, is an important force of historical change. I summarize some of his argument below.
During the High Middle Ages there was a period of significant global warming. Lasting from 750 to 1215, the period is called the Little Climatic Optimum (LCO)--a reference to the Climatic Optimum, the hot period that followed the last glacier period's end, 7 or 8 thousand years ago. Lacking precise human records from the LCO, paleo-climatoloigsts use proxy measures, such as those from tree rings and glacial deposits, to conclude that the planet was warmer and drier than it is now. The warming was greatest in the northern latitudes and in winter (winter temperatures, on average 3.5 degrees Fahrenheit warmer).
During the LCO, there were numerous benefical effects from moderating temperatures. Calm, relatively ice- free seas facilitated Viking exploration of the North Atlantic and settlement of Iceland, Greenland and North America. There are no records of epic storms or significant sea level increases. Agriculture improved. Grapes grew in northern Europe and northern Canada (Vinland), and England produced export-quality wines. Warmer weather also caused forests to recede, allowing easier clearance, and the longer growing seasons and larger, more certain harvests encouraged earlier planting, as well as experimentation with a wider crop varitety and with new agricultural technigues. From the 11th to 13th centuries, crop yield nearly doubled, reaching a level not exceded till the 18th century!
The end of famine in Europe led to a steep population increase, from 27 million in the 7th century to 70 million in 1300. This had various social implications, such as the growth of cities, specializtion of function, and an increase in leisure. The improvement in northern agriculture also had another and more lasting effect: the shift in world power away from the Mediteranean and to northern Europe.
I could go on, but I think I've made my point. Global warming happened before and, when it did, its effects were beneficial, except for those that came out on the losing end of a Viking raid! I recommend you track down Dunn's article for a fuller discussion of his ideas and an excellent list of citations. I also recommend Emmanuel Ladurie's "Times of Feast, Times of Famine," published in 1971, and still the only major book on the subject of climate and its impact on history. A must read!
From proponents of anthropogenic global warming theory, however, one gets the the sense that climate change is usually slow, moving at a geologic pace, and that the current period of global warming is unprecedented. In fact, neither of these propostions are true. There's a great article in the December 2000 issue of Analog Science Fiction and Fact, "Summer's Lease" by J.R. Dunn that puts these misconceptions to rest and suggests that climate change, as an ongoing phenonenon, is an important force of historical change. I summarize some of his argument below.
During the High Middle Ages there was a period of significant global warming. Lasting from 750 to 1215, the period is called the Little Climatic Optimum (LCO)--a reference to the Climatic Optimum, the hot period that followed the last glacier period's end, 7 or 8 thousand years ago. Lacking precise human records from the LCO, paleo-climatoloigsts use proxy measures, such as those from tree rings and glacial deposits, to conclude that the planet was warmer and drier than it is now. The warming was greatest in the northern latitudes and in winter (winter temperatures, on average 3.5 degrees Fahrenheit warmer).
During the LCO, there were numerous benefical effects from moderating temperatures. Calm, relatively ice- free seas facilitated Viking exploration of the North Atlantic and settlement of Iceland, Greenland and North America. There are no records of epic storms or significant sea level increases. Agriculture improved. Grapes grew in northern Europe and northern Canada (Vinland), and England produced export-quality wines. Warmer weather also caused forests to recede, allowing easier clearance, and the longer growing seasons and larger, more certain harvests encouraged earlier planting, as well as experimentation with a wider crop varitety and with new agricultural technigues. From the 11th to 13th centuries, crop yield nearly doubled, reaching a level not exceded till the 18th century!
The end of famine in Europe led to a steep population increase, from 27 million in the 7th century to 70 million in 1300. This had various social implications, such as the growth of cities, specializtion of function, and an increase in leisure. The improvement in northern agriculture also had another and more lasting effect: the shift in world power away from the Mediteranean and to northern Europe.
I could go on, but I think I've made my point. Global warming happened before and, when it did, its effects were beneficial, except for those that came out on the losing end of a Viking raid! I recommend you track down Dunn's article for a fuller discussion of his ideas and an excellent list of citations. I also recommend Emmanuel Ladurie's "Times of Feast, Times of Famine," published in 1971, and still the only major book on the subject of climate and its impact on history. A must read!
No, really, I love anything that says "Take that and stop your whinging, global warming obsessives!"