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It's the Climate, Stupid
02/21/09 12:00 PM
Civilizations rise and fall on the whims of the weather
Anthropologists and historians largely agree that most of the great human civilizations that have disappeared or faded (think the ancient Egyptians, Aztecs, Romans, etc.) met their demise largely due to unfavorable climate changes. Sure, factors such as war, disease and famine played their parts, however, most of these deleterious influences were driven, to no small degree, by climatic shifts that affected particular regions. In other words, long-term weather patterns make or break human civilizations.
And lest you think this isn't happening now, consider one small example among many — California's Central Valley. While not a center for arts or entertainment, and certainly no tourist destination, this sprawling swath (4.7 million acres) of agricultural topography between the Pacific Ocean and the Sierra Nevada Mountains has been among the most productive farming areas in the United States, if not the world. But that is rapidly changing, and the culprit is . . . you guessed it . . . climate. Over the past decade, this area, as well as many others in America's southwest quadrant, has endured a prolonged drought, one that many scientists attribute to the localized affects of global climate change.
The human impact, even over this short span of time, has been swift and dramatic. This year's agricultural losses are pegged at close to $2 billion, and accompanying job losses have hit over 80,000, placing some communities in the area at or near the top of unemployment rates in the United States. The related social costs — alcohol and drug abuse, domestic violence, crime, homelessness — are also rising, leading some locals to describe their communities as belonging to the "third world."
Over 3 million acres in the Central Valley depend on irrigation, lacking sufficient natural rainfall to remain productive. But the prolonged drought has drastically lowered available water, both from rivers and underground aquifers. Overall, the area's irrigation system relies heavily on melt from the snowpack in the Sierra Nevada mountains to the east. However, so far this winter, that snowpack is running around 60% of normal.
Should the drought continue much longer (and climate models suggest it will), portions of the Central Valley may approach "dust bowl" conditions similar to those during the Great Depression. And should the current climate become the "new normal" for the area, agriculture may become untenable altogether, completely changing the social and economic character of the region.
Similar scenarios are being played out in other parts of the globe. Dramatic shifts in temperature, precipitation and biodiversity are threatening to alter the geo-political-economic landscape of our planet, and rapidly, leaving us to wonder which great city, region or nation will become the next lost civilization.
And lest you think this isn't happening now, consider one small example among many — California's Central Valley. While not a center for arts or entertainment, and certainly no tourist destination, this sprawling swath (4.7 million acres) of agricultural topography between the Pacific Ocean and the Sierra Nevada Mountains has been among the most productive farming areas in the United States, if not the world. But that is rapidly changing, and the culprit is . . . you guessed it . . . climate. Over the past decade, this area, as well as many others in America's southwest quadrant, has endured a prolonged drought, one that many scientists attribute to the localized affects of global climate change.
The human impact, even over this short span of time, has been swift and dramatic. This year's agricultural losses are pegged at close to $2 billion, and accompanying job losses have hit over 80,000, placing some communities in the area at or near the top of unemployment rates in the United States. The related social costs — alcohol and drug abuse, domestic violence, crime, homelessness — are also rising, leading some locals to describe their communities as belonging to the "third world."
Over 3 million acres in the Central Valley depend on irrigation, lacking sufficient natural rainfall to remain productive. But the prolonged drought has drastically lowered available water, both from rivers and underground aquifers. Overall, the area's irrigation system relies heavily on melt from the snowpack in the Sierra Nevada mountains to the east. However, so far this winter, that snowpack is running around 60% of normal.
Should the drought continue much longer (and climate models suggest it will), portions of the Central Valley may approach "dust bowl" conditions similar to those during the Great Depression. And should the current climate become the "new normal" for the area, agriculture may become untenable altogether, completely changing the social and economic character of the region.
Similar scenarios are being played out in other parts of the globe. Dramatic shifts in temperature, precipitation and biodiversity are threatening to alter the geo-political-economic landscape of our planet, and rapidly, leaving us to wonder which great city, region or nation will become the next lost civilization.