The number of hectares burned in Canada this year is far ahead of average.
In the United States the acres burned to date are 46 percent above normal. Statistics from May 20, 2016, the last time the National Interagency Fire Center issued a daily Situation Report, show that 1,551,474 acres had burned, compared to the 10-year to-date average of 1,063,835. Almost two-thirds of that was in the Southern Geographical Area — 955,242. The Rocky Mountain Geographical Area also had a surprisingly high figure — 374,846 acres; but that area includes Kansas, where most of the 397,000-acre Anderson Creek Fire occurred in March.
If you disregard that one huge fire, the total in the U.S. is a lot closer to average. But I’m guessing that some politician somewhere is going to take that 46 percent higher than normal figure and run with it.
These numbers do not include prescribed fires. As of May 20 almost 2 million acres in the U.S. have been visited by prescribed fire.
In February we posted some statistics showing that historically there is a large spike in wildfire activity in March and April in Kansas. The spring is also a time when many, many ranchers conduct prescribed fires in the Flint Hills of Kansas and Oklahoma. This year between February 27 and May 5, 2.7 million acres were treated with prescribed fire.
Referring to the bar graph below, and throwing out the two busiest and the two slowest data points, in a typical year land managers in the Flint Hills burn between 1.1 million and 2.8 million acres.
We thank Eric Ward of the Kansas Forest Service for providing these graphics compiled by the Kansas Department of Health and Environment..
The Texas Forest Service released this graphic showing that more acres have burned this year compared to the same period in 2015. The brown (or orange) bars and line are acres burned in 2016, while blue represents 2015.
The University of Wyoming has issued a publication about the patterns, influences, and effects of wildland fire in the state.
The University of Wyoming paper covers basic facts about fire, weather, intensity, severity, prescribed burning, as well as fire effects and interactions with soils, plants, livestock, wildlife, and bark beetle outbreaks. The document is 16 pages long with an additional 8 pages of references and a glossary. It was written by Derek Scasta, Assistant Professor and Extension Rangeland Specialist.
A couple of items attracted my attention. One is the graphic at the top of this article, the mean fire return interval for Wyoming. If you’re familiar with the geography of an area, data like this can absorb your interest for a while. The map appears to be a section taken out of the whole country map.
Another topic covered in the publication is the relationship between precipitation and acres burned.
The chart above from the paper uses the total Wyoming statewide annual precipitation compared with the total number of acres burned in wildfires each year. We have been thinking that the weather in the summer has a greater effect on acres burned than weather throughout the year. Those weather factors include temperature, relative humidity, wind, and precipitation, and a few others used by the National Fire Danger Rating System. It’s beyond our capacity to analyze all of those, unless we use an index that takes multiple parameters into account, such as the Burning Index or the Energy Release Component.
But what we did (immediately above) was to take one weather parameter from the summer and plotted it on a chart similar to the UofW chart– average monthly precipitation each year for June, July, and August. The weather data came from NOAA, and the acres burned was extracted from the University of Wyoming chart.
Included among the disclaimers is that average precipitation across the state does not apply to every square mile. Thunderstorms in the summer could be hammering one area, while a major fire is burning somewhere else. And, using only precipitation does not take into account temperature, relative humidity, and wind, which are all very important.
If anyone is interested in analyzing the Wyoming fire occurrence data using another weather factor or NFDRS Index (from the summer months), below are the numbers I used. Or, if you’d like to look at another state or geographic area, that would be fine. It’s important to analyze the acres burned and the weather observations for a large area in order get a sample of sufficient size to make it statistically significant. For example, use 15 to 20 years of information from a large national forest with multiple weather stations to reduce the data-skewing impact of a gully-washer thunderstorm at one location.
Far more acres burn in March and April in Kansas than the other months.
Wildfire occurrence data collected by the Kansas Fire Incident Reporting System shows that over an 11-year period, from 2004 through 2014, there were two spikes in the number of reported fires during the year — in March/April and in July. However, by far, most of the acres burned in March and April.
Below are excerpts from a Kansas State University article written by Chip Redmond and Mary Knapp of the University’s Weather Data library.
“…Of the eleven years of recorded KFIRS data, 2014 had both the most land area burned (187,500 acres) and the highest number of reported fires (8,075) in a year. In both land area and number, fires followed the typical curve of the previous 10 years, with a peak during the spring months of March and April.
This trend of spring wildfires coincides very well with prescribed burning season. Early spring is typically characterized by dead/cured fuels, warming temperatures, low relative humidity, and little precipitation. Often, if the late fall and winter are below normal in precipitation and/or the region is in a drought, these spring conditions are enhanced – providing explosive conditions for fire growth.
This was the case entering 2014. However, conditions were worsened by an increased fuel load from late summer rains of 2013 that brought some relief to the prolonged drought which peaked in 2012.These combined factors led to a peak of 156,600 acres burning in March/April 2014 alone. Of the 61 days possible in March and April, almost half (29) had more than 1000 acres burned statewide each day. Two days (Jan. 26 and Feb. 19) occurred outside of these months. Below, the March/April calendar with red days were those in which more than 1000 acres statewide were burned. Cold frontal passages throughout the period are marked on their associated day. Continue reading “March and April are historically busy for wildland firefighters in Kansas”
For the last several days we have been writing about fatalities on wildland fires — the annual numbers and trends going back to 1910 and some thoughts about how to reduce the number of entrapments (also known as burnovers). Often when we think about these accidents, what automatically comes to mind are the entrapments. When multiple firefighters are killed at the same time it can be etched into our memory banks to a greater extent than when one person is killed in a vehicle rollover or is hit by a falling tree. Much of the nation mourned when 19 members of the Granite Mountain Hotshots were overrun and killed by the Yarnell Hill Fire in Arizona in 2013. A fatal heart attack on a fire does not receive nearly as much attention.
When we discuss ways to decrease deaths on fires, for some of us our first thoughts are how to prevent entrapments, myself included. One reason is that it can seem they are preventable. Someone made a decision to be in a certain location at a specific time, and it’s easy to think that if only a different decision had been made those people would still be alive. Of course it is not that simple. Perfect 20/20 hindsight is tempting for the Monday Morning Incident Commander. Who knows — if they had been there with access to the same information they may have made the same series of decisions.
An analysis of the data provided by NIFC for the 440 fatalities from 1990 through 2014 shows that entrapments are the fourth leading cause of fatalities. The top four categories which account for 88 percent are, in decreasing order, medical issues, aircraft accidents, vehicle accidents, and entrapments. The numbers for those four are remarkably similar, ranging from 23 to 21 percent of the total. Number five is hazardous trees at 4 percent followed by the Work Capacity Test, heat illness, and electrocution, all at around 1 percent. A bunch of miscellaneous causes adds up to 4 percent.
NIFC’s data used to separate air tanker crashes from accidents involving other types of aircraft such as lead planes and helicopters. But in recent years they began lumping them all into an “aircraft accident” category, so it is no longer possible to study them separately. This is unfortunate, since the missions are completely different and involve very dissimilar personnel, conflating firefighters who are passengers in the same category as air tankers having one- to seven-person crews — from Single Engine Air Tankers to military MAFFS air tankers.
The bottom line, at least for this quick look at the numbers, is that in addition to trying to mitigate the number of entrapments, we should be spending at least as much time and effort to reduce the numbers of wildland firefighters who die from medical issues and accidents in vehicles and aircraft.