Category: being a scientist

The Nugget Creek fire, and how fires are managed in Alaska

The numerous wildfires currently active in interior Alaska have made it a pretty miserable last day of the holiday weekend (Independence Day was Thursday in the US). The Fairbanks area is blanketed in smoke so badly that there’s a dense smoke advisory in effect and the local hospital has set up a smoke respite room for people with respiratory issues.

Most eyes are on the Shovel Creek fire NW of Fairbanks, which is burning very close to residential neighborhoods in mature black spruce forest, which naturally burns every ~100 years or so (plus/minus a large interval). It is managed by a Type 1 team – these are nationally managed in the US, and have the largest amount of experience and resources. There have been regular public information meetings, and the fire even has its own YouTube channel.

I live about 30 miles east of town, and over here, even though smoke these days comes from any of multiple fires in the wider area, the one we’re most concerned with is the Nugget Creek fire. It’s roughly the same order of magnitude as the Shovel Creek fire (a little smaller – 7000 acres / 2800 ha as of today, and growing – but unlike its companion, has not received any suppression activity at all, even though it’s only about 10 miles (16 km) from a residential area.

Why? This has to do with how decisions about fire management are made in Alaska. All of Alaska is divided into one of four fire management options. If you follow the link you’ll see that most of the remote areas are in the “limited” option. Here, fire is by default allowed to fulfill its natural ecological function, though known cabins and infrastructure is being protected by firefighters on the ground and from planes. Also, reconnaissance flights are being carried out, and fires are monitored. On the other extreme is the “critical” management option, where all fires are immediately suppressed. Towns and villages are covered by these. In-between, there are two intermediate options, “full” (covering the major road corridors, mining areas etc.) and “modified”. (These options are used for prioritization – there is no mechanical

The Nugget Creek fire started in the Chena River State Recreation Area, in a location that is in the “limited management option. Here’s a map of the fire and how it is just nestled into the green, “limited” area. The fire is in red on the right, with the spots indicating where active fire was detected by satellite imagery. The fire has been pretty active on nearly its entire perimeter.

Source: Alaska Fire Service GIS (click for larger image)

But it is still nearly entirely in the area that belongs to the limited management option. To the north, the full option starts at the Chena River and/or Chena Hot Springs Road, approximately. To the west, the modified option starts at the south fork of the Chena River (the confluence is where green, brown and blue areas meet). There are some fire service staff assigned to the fire, who have been continuously monitoring where the fire is relative to river/road in the north, and also have set up sprinklers to protect a public use cabin on the south fork of the Chena River (Nugget Creek cabin).

I’m pretty sure that we’ll see some drops of water or retardant if the fire service thinks it may jump over the river or road in the north. There are more reasons to think it won’t spread too far west or east: not only is the western side quite swampy and full of sloughs (and of course a small river), but there are also recent fire scars in the area, which would slow down a fire. The blue area is already within the scar left by the 2013 Stuart Creek 2 fire, and the area east of the fire burned in 2009 or 2000:

Nugget Creek fire as of July 6, with active fire detections around its perimeter. Old fire scars surround the area. The stars indicate where we live, and the location my spouse and I are in the process of moving to. (click for larger image)

So what do I expect will happen? My guess is that the fire will burn out a good part of the triangle between rivers and old fire scars. It’ll be several days before we can expect rain, so smoke will stay terrible for a while.

In any event, Nugget Creek will be an interesting case study for testing models of how fire spreads: It’s one of the few fires that will be relatively easily accessible on foot (once it is completely out of course!), as it has reached Mastodon Creek Trail in the east and is visible from two bridges over the Chena River. And it will have been essentially unsuppressed, ie left ti its natural progression, at least until now.

What I do using the ten hundred most common English words

What better way to start a geoscience blog than to jump on a memetic bandwagon, right? Inspired by an XKCD cartoon — what else — a creative person called Theo Sanderson coded the Up-Goer Five text editor to incide people to write about a hard idea using only the most common 1000 (ten hundred, as “thousand” is forbidden) words of the English language. I’m not going to quibble about his selection at the lower edge of the 1000 number: it’s a charming idea and it became a geo-blogger meme. So here’s my attempt:

In the colder parts of the world a lot of the land is covered by trees. Every summer, some of the trees catch on fire. The fires can grow very large and burn a lot of the wood and other ground cover. Many of the fires happen far away from people because not many people live up here, but the smoke from the fires moves with the wind so in the towns and other places where people live they often can smell it. The smoke and little black bits from the fires are bad for people, especially children and sick people.

I work with a group that uses computers to find out where the smoke from the fires will move. We run the computers for hours and then make pictures of the land and put them where people can see them. There are the cities on the pictures and red and green and blue and so on, so people can see if there is going to be smoke where they live. To make the pictures we need to find out very fast when there is a new fire, and how big it is. For this I use other pictures — very large pictures that are taken from space. I get those pictures on my computer and have written something that makes the computer take a very close look at the pictures and tell me where the fires are and how big they are.

Another way to use the computer is to make it figure out where a fire is going. This is very hard for the computer, because it needs to know what grows on the ground, if there is water on the ground or rain falling, where the ground goes up and down, and so on. So I use a computer made from over one hundred smaller computers to make a picture of where the fire will be the next two or three days.

We also know that the cold parts of the world are getting warmer, and it is important to know if there are going to be more fires or maybe larger fires or the same place burns more often. This is a very interesting job to do.

More here.