martes, mayo 09, 2006

FIJAOS LO QUE HACÍA la contaminación de fábricas y automóviles en la Edad de Bronce: el calentamiento global era tan acentuado que, en Noruega, las mujeres llevaban minifalda.



(aquí podéis ver cómo le queda a una chica de carne y hueso)

Y es que, como dice Thomas Gale Moore, de la Hoover Institution en la universidad de Stanford, lo mejor que puede pasar para el bienestar de la humanidad es que el planeta se caliente:
History demonstrates that warmer is healthier. Since the end of the last Ice Age, the earth has enjoyed two periods that were warmer than the twentieth century. Archaeological evidence shows that people lived longer, enjoyed better nutrition, and multiplied more rapidly than during epochs of cold.

That Ice Age ended about 12,000 to 10,000 years ago when the glaciers covering much of North America, Scandinavia and northern Asia began to retreat to approximately their current positions. In North America the glacial covering lasted longer than in Eurasia because of topographical features that delayed the warming. Throughout history warming and cooling in different regions of the world have not correlated exactly because of the influence of such factors as oceans, mountains, and prevailing winds.

As the earth warmed with the waning of the Ice Age, the sea level rose as much as 300 feet; hunters in Europe roamed through modern Norway; agriculture developed in the Middle East, the Far East and the Americas. By 7,000 years ago and lasting for about four millenniums, the earth was more clement than today, perhaps by 4deg. Fahrenheit, about the average of the various predictions for global warming from a doubling of CO2. Although the climate cooled a bit after 3000 B.C., it stayed relatively warmer than the modern world until sometime after 1000 B.C., when chilly temperatures became more common. During the four thousand warmest years, Europe enjoyed mild winters and warm summers with a storm belt far to the north. Rainfall may have been 10 to 15 percent greater than now. Not only was the country less subject to severe storms, but the skies were less cloudy and the days, sunnier.

From around 800 A.D. to 1200 or 1300, the globe warmed again considerably and civilization prospered. This warm era displays, although less distinctly, many of the same characteristics as the earlier period of clement weather. Virtually all of northern Europe, the British Isles, Scandinavia, Greenland, and Iceland were considerably warmer than at present. The Mediterranean, the Near East, and North Africa, including the Sahara, received more rainfall than they do today. During this period of the High Middle Ages, most of North America also enjoyed better weather. In the early centuries of the epoch, China experienced higher temperatures and a more clement climate. From Western Europe to China, East Asia, India, and the Americas, mankind flourished as never before.

This prosperous period collapsed at the end of the thirteenth century with the advent of the "Mini Ice Age" which, at its most frigid, produced temperatures in central England for January about 4.5deg.F colder than today. Although the climate fluctuated, periods of cold damp weather lasted until the early part of the nineteenth century. During the chilliest decades, 5 to 15 percent less rain fell in Europe than does normally today; but, due to less evaporation because of the low temperatures, swampy conditions were more prevalent. As a result, in the fourteenth century the population explosion came to an abrupt halt; economic activity slowed; lives shortened as disease spread and diets deteriorated.

Although the influence of climate on human activities has declined with the growth in wealth and resources, climate still has a significant effect on disease and health. A cold wet climate can confine people to close quarters, abetting contagion. In the past, a shift towards a poorer climate has led to hunger and famine, making disease more virulent. Before the industrial revolution and improved technology, a series of bad years could be devastating. If transportation were costly and slow, as was typical until very recently, even a regionalized drought or an excess of rain might lead to disaster, even though crops might be plentiful a short distance away.
Seguid leyendo.