It’s not your imagination. Wildfire seasons are getting worse, and the West is getting drier

Wildfires this summer have stretched government resources to their limits. (Uriah Walker/U.S. Army photo)

One of the great talking points of late has been the severity, or even the existence, of climate change. There was a time, maybe just short of 30 years ago, when the scientific and political consensus were on the same track, agreeing that man-made carbon and methane emissions were changing the climate.

A lot of industry pushback, in the form of like-minded politicians and convincing-looking counternarratives, soon cropped up. Arguments of “job-killing regulations” and no small amount of doubt-sowing opinion pieces, studies and so forth muddied what was at one time a clearer picture. And to be frank, the far-off implications of what might happen didn’t move the meter much in terms of public opinion.

What people needed was evidence. Evidence they could see. And not just data, which for some reason, people just don’t trust as much as what they see with their own eyes. Bad things were coming, we were told. But for most, out of sight means out of mind.

The trouble with this line of thinking is that when you finally see the negative consequences that were predicted all along, it’s likely too late. And that’s what we’ve seen come to pass in the American West.

Two things come to mind, things that are not only measurable, but visible.

The first is the expanding wildfire season, and the growth of its severity.

The Union of Concerned Scientists recently published these facts on the subject:

Between 1980 and 1989, the American West averaged 140 wildfires of 1,000 acres or larger every year. Between 2000 and 2012, that number nearly doubled, to 250.

The wildfire season has grown in length. In the 1970s, the season lasted about five months. Now it’s up to seven months.

As western states heat up, snowpack is melting four weeks earlier than normal. Hotter, drier forests are becoming more vulnerable to more frequent and more destructive wildfires.

A satellite image of wildfires in California. (NASA image)

The journal Nature confirmed this with its own research, noting that this is a global problem:

“Climate strongly influences global wildfire activity, and recent wildfire surges may signal fire weather-induced pyrogeographic shifts. Here we use three daily global climate data sets and three fire danger indices to develop a simple annual metric of fire weather season length, and map spatio-temporal trends from 1979 to 2013. We show that fire weather seasons have lengthened across 29.6 million km2 (25.3%) of the Earth’s vegetated surface, resulting in an 18.7% increase in global mean fire weather season length. We also show a doubling (108.1% increase) of global burnable area affected by long fire weather seasons (>1.0 σ above the historical mean) and an increased global frequency of long fire weather seasons across 62.4 million km2 (53.4%) during the second half of the study period. If these fire weather changes are coupled with ignition sources and available fuel, they could markedly impact global ecosystems, societies, economies and climate.”

And from NASA, data show that as bad as things are looking in the western U.S., the problem is significantly worse in eastern Brazil, east Africa and western Mexico.

The statistics for 2018 obviously aren’t in yet, but if it seems like the entire West is on fire, you’re not too far off target. Drought in the U.S. Southwest created massive wildfires in Arizona, northern New Mexico and southwestern Colorado. Wildfires later erupted in Utah and Wyoming. Record-setting blazes are scorching California once again, and massive fires are currently burning in Montana and British Columbia. It’s one of the worst fire seasons I can remember, and my guess is by the time 2018 ends, it could be a record-setter.

Lengthening, more damaging wildfire seasons are one thing. But there’s more. The nature of the arid west is changing, too. It’s growing.

NPR recently reported this:

“The American West appears to be moving east. New research shows the line on the map that divides the North American continent into arid Western regions and humid Eastern regions is shifting, with profound implications for American agriculture.”

A meridian running through the plains of Canada and the U.S. and into Mexico is seen as the diving line between the drier West and the wetter East. Researchers, according to NPR, are discovering that line is moving east, increasing the size of the Rocky Mountain rain shadow and making the breadbasket of the U.S. that much smaller. Farmers are finding it more difficult to successfully irrigate their crops (and the depletion of the Ogallalah Aquifer will only make this harder), so they’re switching to ranching, which is less water-intensive.

The arid climate of the West is edging its way into the wetter, more humid East. And that will affect agriculture and livelihoods for people in the Great Plains.

Right now, it’s difficult to measure the impact of this shift, but you can imagine its potential significance. Production of food and biofuels lies with the success of agriculture in the Great Plains. If that becomes less tenable in places like the Dakotas, Nebraska, Kansas, Oklahoma and Texas, the shift will be felt not only by the farmers themselves, but consumers in the U.S. and abroad. The real question becomes one of figuring out how far east that dry/wet dividing line will go.

At one time, people might have wondered what climate change will look like. Well, now we know. It means longer, more intense fire seasons. It means less land for farming, and a fundamental change in the lifestyles of people making a living in the Great Plains.

In other words, some people asked for evidence. Now you can see it for yourself.

Bob Doucette

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