A sea of relative tranquility in a fiery summer

By Jayson Jacoby September 28, 2012 11:48 am

By Jayson Jacoby

Baker City Herald Editor

Wildfires have been much in the news this summer, as is typical here in the arid inland West.

Yet Baker County ranks as something of a tranquil anomaly amidst the breathless recounting of square miles scorched, and the dramatic scenes of leaping flames.

With the notable — and unfortunate — exception of the Sardine fire in mid-August, which temporarily damaged about 6,100 acres of valuable livestock grazing land east of Baker City, the 2012 fire season hereabouts has been distinguished by the absence of fire rather than the abundance.

This despite fire danger indices so severe that open burning has been banned for weeks across much of the region — including in Baker City’s back yards.

(And front and side yards, for that matter.)

We certainly haven’t been spared the drought that has plagued much of Oregon and several other states.

We did in fact endure the third-longest dry spell since at least World War II (rainfall records at the Baker City Airport date to 1943).

The explanation for this apparent contradiction requires a single word.

Lightning.

We weren’t bombarbed with the usual number of high-voltage bolts this summer.

This is significant because lightning — not carelessly tossed cigarettes, fireworks,  abandoned campfires or Bigfoot pounding two sticks together to announce a potluck — starts a majority of the wildfires in Baker County.

The percentage is highest on the Wallowa-Whitman National Forest, where over the past four decades or so, lightning supplied the spark in about 80 percent of the blazes.

(This year the percentage has been lower, with 41 of 72 fires — 57 percent — caused by lightning.)

On private property the proportion of human-caused wildfires is higher than on public land.

On lands in Northeastern Oregon protected by the Oregon Department of Forestry, for instance — most of the acres privately owned — people were responsible for 21 fires this summer, and lightning for 18 fires.

The bottom line is that there exists a strong correlation in our region between the frequency of lightning and the severity of the fire season, as measured by the number of acres burned.

To put it another way, those ubiquitous warnings about extreme fire danger, though valid and necessary, reflect the relative risk rather than a fiery certainty.

This difference seems to me to get lost, or at least is glossed over, in much of the media coverage during fire season.

Extreme fire danger means that if a blaze is kindled, it’s more likely than usual to spread quickly; that designation doesn’t, though, necessarily mean the chances of ignition are abnormally high.

The lightning/fire season severity link isn’t the only one that strikes me as noteworthy in this matter.

In fact, it’s frequently true that as the fire danger rises, the threat of lightning declines.

This summer illustrated this inverse relationship with acute clarity.

The recent dry streak, as I mentioned, was an abnormally lengthy one — 70 days without measurable rainfall at the Baker City Airport.

Only 1987 (79 days), and 1999 (72 days) had longer dry spells.

What does this have to do with lightning?

Quite a lot, actually.

The main source of rainfall in Baker County during July and August is the thunderstorm.

Which, of course, spawns lightning.

Until the light showers on Sunday, the last measurable rain at the airport fell on July 14, during a nasty thunderstorm storm that elsewhere dumped hail that damaged potatoes, alfalfa and other crops.

Since then the only major lightning storm — Sunday’s rain was not accompanied by atmospheric pyrotechnics — was the one that ignited the Sardine fire.

Statistics aside, I’d relish a rainstorm rather more robust than what we got Sunday, which was closer to drizzle than to downpour.

A heavy rain would curb the fire danger, and lay the dust besides.

The last few times I’ve gone hiking, the trail (and in a couple cases a dirt road) was coated in a fine powder so thick that every step was akin to dropping a five-pound bag of flour on the kitchen floor.

Only not as white.

And with no chance of getting a plate of cookies from the deal.