In Elizabeth Kolbert’s, “Butterfly Lessons”, January 2006, New Yorker article, the effects of global warming on species migration and extinction are discussed. She gives scientific information with enough personal narrative to keep me interested in it as a story. As the title would indicate the story begins with butterflies in Europe and their well documented migration northward. Reason for this is not given. Only the fact that thorough mapping has been done for the past 30 years and 22 of 35 species have shifted north.
The article shifts to global CO2 levels and how much they have risen in the last 10,000 years. With industry and coal burning, levels of CO2 have risen more in the last 200 years than they did in the previous 10,000. Projected rises in temperature caused by the rise in CO2 levels are between three and a half and seven degrees by 2050. A three degree rise would make the earth hotter than it’s been in two million years.
More examples are given of how the effects of climate change can be observed in the natural world. These include earlier mating of frogs in New York, spring flowering shrubs in Boston blooming earlier, Costa Rican toucans nesting higher up in the mountains, plants in the Alps growing at higher elevations, Californian butterflies found 300 feet higher in the Sierra Nevada mountains, East Coast mosquito reproduction habits, and the extinction of the Costa Rican golden toad.
The earth has gone through dramatic climate changes, at least 20 in the past two million years. The last shift was 10,000 years ago when the earth started warming up again. At the rate we are now warming, we will see a rise in temperature in 100 years that up till now took 10,000 years and the earth has never been as warm as is predicted. We don’t know what to expect in how it will affect species including diseases. There is overwhelming evidence that species distribution is changing and will continue to change but there is no way of knowing exactly how.
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