Sunday, July 20, 2014

Huge Forest Fires Are Bad In More Ways Than You Think

Friday afternoon and Saturday, the sky over my house in northwestern Vermont took on a brassy pallor.
A massive fire in Northwest Territories, Canada last week.  

The deep blue sky had turned milky, the sunshine had sort of an orange-ish color, and a bit of haze made some of the Green Mountains seem bluish and blurry.

Blame the big forest fires in Washington State and western Canada for that.

Smoke from the huge fires, hoised aloft, blew thousands of miles in high upper atmospheric winds and went clear across the country to New England.

That the smoke slightly dulled a bright Vermont summer day is the smallest negative effect that these huge fires have around the world.

Yes, the fires destroy forests and the homes of people who live there. That's the most obvious reason out of control wildfires are bad things.  The fire in Washington, for instance, has destroyed more than 100 homes as of Sunday. 

But the fires are also a health hazard for people with breathing problems, probably worsen global warming, and cause huge problems when the droughts that helped start the fires end and the rains begin.
A big forest fire in Oregon last week. 

Many observers see the many of these fires, like the one in Washington State, the big blazes underway in Canada's Northwest Territories, and epic conflagrations in recent years in Siberia, as signs of global warming. 

The far north in particular, northern Canada, Alaska, and Siberia, have warmed up a LOT in recent decades, more than the rest of the world.

That means there's snow on the ground for a shorter time of year and the boreal forests up that way have a bigger chance to dry out in the warm season.

Then they catch fire.

Even worse, these fires set the stage for even more global warming. Soot from the fires can travel thousands of miles, and settle on ice in the Arctic Ocean, and on the great ice sheets of Greenland.

Normally, this ice is pretty white and reflects the summer sun away, so melting is minimized to an extent, even when the Arctic is warmer than normal.

But these tiny particles of soot settling on the ice collect the sun's heat, and hasten melting. That might be partly why the polar ice cap has gotten so much smaller in recent decades (though a warmer Arctic climate still takes most of the blame)

In Greenland, the soot has helped melt the ice sheet faster, and that's even worse than the ice on the Arctic Ocean melting.  That ice melt runs off into the oceans, contributing to worldwide rises in sea levels.

Ultimately, those fires in northwestern Canada, then, are helping to drown cities like Miami and Norfolk Va.

The fires are also very bad for those of us who like to breathe. This is true even for people who live far away from the blazes.

In 2002, fires in northern Quebec blew smoke southward to where I live in Vermont.  The same thing happened in 2010 and 2013. There were air pollution warnings galore during these episodes, because the tiny particulates in the air could cause lung damage.

With the fires burning in Washington this week, air pollution alerts extended into Idaho and Montana, two places you normally don't think of as having dangerous air pollution. But there you go.

After the fires are out and the rains come, the blazes still cause huge problems. There's no vegetation left to soak up the rain.  The downpours cause runoff, which leads to flash floods, mudslides and debris flows.

That is a constant problem in California after the seasonal fires when the winter rains return. (At least we hope they do this year.

Last year, after fires in the Waldo Canyon area of Colorado, heavy thunderstorms hit later in the summer. So you get scenes like this:

No comments:

Post a Comment