2010 Diary week 29
Global warming, climate change and weather extremes
Book Review
Part II of the review of The Weather Makers: How Man is Changing the Climate and What it Means for Life on Earth by Tim Flannery will be posted in the next few days. These are some snippets from the review: “The ice age in which we evolved covers the last 2.4 million years. 2,000 fertile adults were all that stood between us and extinction. 13,000 years ago as the ice waned for a final time, our numbers increased rapidly, we occupied new lands and even discovered the Americas.” “Antarctic ice cores allow us to glimpse how things stood 430,000 years ago – the last time that the Milankovitch cycles brought Earth into a position similar to that which it occupies today.” “The warm (interglacial) period was exceptionally long. Warm phases – even far briefer ones than the present – were however, anomalies during the ice age. More typical are cold periods, including the so-called glacial maxima, when the grip of the ice is at its greatest. The last time this happened was between 35,000 and 20,000 years ago when the sea level was more than 300 feet lower than it is today.” “North America and Europe’s most densely inhabited landscapes lay under miles of ice. Even regions south of the ice, such as central France, were treeless subarctic deserts with a growing season of 60 days.” “Around 20,000 to 10,000 years ago the overall surface temperature of Earth warmed by 9ºF – the fastest rise recorded in recent Earth history. If we pursue business as usual, an increase of 5ºF (give or take 3ºF) over the 21st century seems inevitable. The fastest warming recorded back then was a mere 2ºF per thousand years.”