When people talk about the risks of global warming, the discussion usually centers around rising ocean levels. We are all of us, skeptics and believers alike, aware of the images of Florida half-submerged, the Pacific islands obliterated, Louisiana gone. Too much water will flood coastlines throughout the world, bringing destruction in its wake.
But the effect of global climate change is not always as obvious as a hurricane, not always as clear as a flood. It isn't always about too much water. As a recent series of stories shows, sometimes it's about too little.
In the deep south, a massive drought has had a catastrophic negative impact on agriculture. Lake Lanier, which provides water for most of metropolitan Atlanta, is at its lowest rate in fifty years, sparking a state of emergency. The typical squabbling has ensued -- Georgia has no water management plan, and has only just now begun to implement usage restrictions -- but the potential for catastrophe is real.
Meanwhile, a New York Times Sunday Magazine piece informs us that in the Rockies, the snow packs that feed the Colorado River are shrinking, as they melt away with global warming, and are not replenished by reduced winter snowfall. As years go by, the amount of water entering the river will be reduced. The results are already beginning to show. Lake Mead, the reservoir that sits at the Hoover Dam, is half-full, and projections indicate that it will never be full again.
The Colorado River provides water for Colorado, Utah, Wyoming, New Mexico, Arizona, Nevada and California, and a reduced flow would be disastrous. The New York Times quotes Steven Chu, a Nobel Prize-winning scientist, as saying, "There's a two-thirds chance there will be a disaster, and that's in the best scenario."
Turn on any television and you'll see the current situation in California, where wildfires burn out of control, spurred by Santa Ana winds and rainfall two-thirds lower than normal. Almost 100,000 square acres are ablaze, and half a million people have been evacuated from San Diego.
Closer to my home, North Dakota has been in a years-long drought, costing many farmers their livelihoods. Lake Superior's water level appears to have stabilized, but only after falling precipitously.
The problem of global climate change does not lie simply in warmer temperatures. It also lies in the way that the world's biomes will be reshuffled. Richard Seager, a scientist at Columbia University, put it bluntly when asked about the west. In an interview with the New York Times, he said, "You can't call it a drought anymore, because it's going over to a drier climate. No one says the Sahara is in drought."
We have reached a point where the impact of global warming is undeniable to any but the most determined skeptic. Some of the impact is inevitable; I fear that within our lifetimes, we'll see the states in the mountain west facing severe water shortages, and demand for states like my native Minnesota, where we have a great deal of fresh water available, to share the wealth. My state must begin immediately to plan for that future, to ensure that we can help our fellow Americans without destroying our own state's environment. And humans must immediately begin to work to curb global carbon emissions. We are already seeing negative effects from our previous lackadaisical attitude, and I fear that we are already too late to avoid catastrophe. We must act soon to avoid apocalypse.
(Cross-posted from Minnesota Monitor)