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Thursday, October 25, 2007
By Steven Milloy

Are climate alarmists using the Southern California wildfires to fan the flames of global warming?

Are environmentalists and government bureaucrats using global warming to cover up their share of responsibility for the wildfires that have displaced more than 500,000 people and destroyed more than 1,300 homes?

The CBS news show "60 Minutes" — which has a history of promoting climate alarmism — kicked off the blame-global-warming campaign last Sunday with a segment entitled "The Age of Mega-Fires."

Reporter Scott Pelley prompted chief federal firefighter Tom Boatner with the statement, "You know, there are a lot of people who don't believe in climate change."

Boatner responded: "You won't find them on the fire line in the American West anymore, because we've had climate change beat into us over the last 10 or 15 years. We know what we're seeing, and we're dealing with a period of climate, in terms of temperature and humidity and drought, that's different than anything people have seen in our lifetimes."

CNN's Anderson Cooper incorporated the fires into his plug for the cable channel's alarmist program "Planet in Peril."

"At the top of the next hour, as I said, the big picture," said Cooper. "These fires are really a piece of it. Fire, drought, global warming, climate change, deforestation, it is all connected. Tonight, 9:00 p.m. Eastern — 'Planet in Peril' starts in just 30 minutes."

It came as no surprise, then, that Senate Majority Leader Harry Reid, D-Nev., told reporters this week, "One reason why we have the fires in California is global warming."

Is this true?

The alarmists' line of reasoning appears to be that: one, man-made carbon-dioxide emissions increase global temperature; two, increased global temperature alters atmospheric conditions to prevent rainfall; and three, ensuing drought conditions are exacerbated by warmer temperatures that increase drying on the ground.

This line of thinking falls apart at the very beginning, of course, since it's not at all clear that global temperatures are driven by atmospheric levels of carbon dioxide.

Note to readers: A video debate on this point produced by me can be viewed by clicking here.

But for the sake of argument, we will continue down the path of the alarmists' thinking.

So does rising global temperature cause drought?

In the context of what appears to have been a one-degree Fahrenheit rise in mean global temperature since 1900, the observed relationship between temperature and precipitation in North America does not favor the hypothesis.

During the period 1900-2005, precipitation seems to have actually increased in areas above 30 degrees north latitude — including California and the rest of the U.S. — according to the most recent assessment from the United Nations' Intergovernmental Panel on Climate Change.

This does not mean, of course, that droughts haven't occurred in North America over the last 100 years, but it doesn't support a link between rising global temperature and increased drought.

Examining the occurrence of drought in southern California since 1900 is also illuminating.

According to data maintained by the federal National Climatic Data Center, drought conditions are no stranger to southern California.

During the period 1900 to 2005, moderate-to-severe drought conditions occurred in Southern California during 34 of those 106 years — that is, about one-third of the time.

Comparing the southern California drought record against the global temperature record reveals the following:

— During the period 1900-1940, when most of the 20th century's one-degree Fahrenheit temperature increase occurred, there were 7 years of moderate-to-severe drought.

— During the period 1941-1975, when global temperatures cooled, giving rise to concerns of a looming ice age, there were 11 years of moderate-to-severe drought.

— During the period 1976 to 1990, when global temperatures rose back to the 1940 level, there were 8 years of moderate-to-severe drought.

— Since 1991, when global temperatures rose slightly past the 1940 levels, there have been 7 years of drought.

It's a record that would seems to largely prevent any simple conclusions from being drawn — that is, rising temperatures with few drought years, followed by falling temperatures and increasing drought frequency, followed by temperatures rising back to the original levels with increased drought frequency, followed by a leveling off of drought occurrence despite higher temperatures.

Though there is no obvious relationship between global temperature and drought in southern California, the alarmists nevertheless advocate the quixotic task of preventing drought and wildfires by controlling greenhouse-gas emissions.

Global warming, it seems, also makes a good excuse for federal and state bureaucrats and politicians who have failed to properly manage high-risk areas, at least in part because of pressure from anti-logging and anti-development environmental groups.

We can be better prepared for drought and wildfires by improving forest management — as this column previously suggested in the aftermath of the deadly California wildfires of 2003.

Drought and forest fires happen. We have no reason to think that we can do anything to prevent the former, but we know that can do a lot about preventing and controlling the latter — if only the environmentalists will let us.

Steven Milloy publishes JunkScience.com and DemandDebate.com. He is a junk science expert, and advocate of free enterprise and an adjunct scholar at the Competitive Enterprise Institute.