The number of wildfires and acres burned by wildfires are the most common metrics used to report current fire season statistics. When an especially large fire is burning, it captures media and public attention. However, fire size is a poor measure of impact.
Large wildfires represent only 2-3% of all wildfires in the US but burn over 90% of the area. As such, they have a disproportional impact on firefighting costs and ecosystems. Extremely large fire events (> 40,000 acres), sometimes termed megafires1 are mostly associated with extreme fire weather and impacts. Not all large fires are equally impactful on society. For example, the 2011 Wallow Fire burned over 500,000 acres in Arizona and New Mexico with property damage estimated at $109 million. The 2018 Camp Fire, which burned just over 150,000 acres, caused an estimated $16.6 billion in losses and killed at least 85 people.
Fire Severity and Ecosystem Impacts
Historically, large fires were a common occurrence throughout the western US. Due to fuel buildup from long-term fire deficits in the 20th century, fires are burning much more severely today with severe consequences to human communities and ecosystems.
To assess fire impacts to ecosystems and important values - recreation, clean water, carbon sequestration and timber production – we need information about how severely fires burn. The Monitoring Trends in Burn Severity program uses pre- and post-burn satellite imagery to map changes in the reflectance of soils and vegetation following fire. Changes in reflectance have been calibrated with fire severity and are generally classified as high, moderate, low, and unburned/low severity.
Recent trends in forest fire severity are alarming2,3. Many of our nation’s old and mature forests are burning in large high severity fires. On dry sites, high severity fires may be wiping forests permanently off the map to be replaced by grasslands or shrublands. On many sites throughout the western US, tree regeneration is challenged by warm and often drier summers.
Appropriate Metrics for Wildfire Impact
Viewing wildfires in terms of impacts to communities and ecosystem services is a better way approach to differentiating between wildfires that have negative impacts for society and those that have little impact to society and are good for ecosystems. Recommended terms:
1 Linley, G.D., Jolly, C.J., Doherty, S. et al. 2022. What do you mean, ‘megafire’? Global Ecology and Biogeography. https://doi.org/10.1111/geb.13499
2 Parks, S. A., and J. T. Abatzoglou. 2020. Warmer and drier fire seasons contribute to increases in area burned at high severity in western US forests from 1985–2017. Geophysical Research
3 Hagmann, R.K., Hessburg, P.F., Prichard, S.J. et al. 2021. Evidence for widespread changes in the structure, composition, and fire regimes of western North American Forests. Ecological Applications 31: e02431. https://doi.org/10.1002/eap.2431
We are hiring 5 field technicians to work at the Teakettle Experimental Forest for the 2022 summer field season. The Teakettle Experimental Forest is a 1300 ha old-growth, mixed-conifer forest located 80 km east of Fresno, CA in the southern Sierra Nevada. The 2022 field season will focus on collecting pretreatment data for a catchment wide prescribed burn. The crew will be tasked with establishing experimental plots, mapping forest structure using a surveyor’s total station, basic tree measurements, and conducting fuels transect surveys. Additionally, the crew will be tasked with conducting understory vegetation surveys and identifying the local flora to the species level. The crew will also assist visiting scientists with their projects as needed. These projects may include basic soils work (coring, soil moisture, etc.), seedling inventories, and tree coring. Desired skills include plant identification, use of a total station, basic knowledge of tree measurements, and previous experience working as a crewmember. The facilities at Teakettle are rustic due to the remote location of the station. The cabin has solar power, bathrooms, a kitchen, and common space. Individuals will spend the summer sleeping in tents. The nearest town for supplies is Shaver Lake, CA, approximately a 1-hour drive from the field station. There is no WIFI or cellphone service at the field station but there is a landline.
The pay rate is $16/hour and crew members will work four 10-hour days each week with 3-day weekends. The field season will run for 12 weeks from the middle of June to early September. The official start date will be determined in late April.
Preference will be given to applicants who have spent at least one season working on a field crew or have experience working at a remote field location. Preference will also be given to applicants who have prior experience with plant identification, basic tree measurements (i.e., DBH), line-intercept sampling or use of a total station. Please note that an up to date COVID-19 vaccination is required for this position.
How to Apply:
To apply, you will need to apply through the University of New Mexico’s Job Portal. First, go to UNM Jobs (https://unmjobs.unm.edu/) and select “Search for a Job”. In the search bar, search “req18591”, “Field Research Tech”, or “Teakettle”. Once the listing has appeared, select “Apply Now”. Review of applications will begin on February 14, 2022. Applications will be reviewed until all positions have been filled. Please note that a New Mexico Driver’s License IS NOT REQUIRED for this position.
If you have any questions regarding the application process or about the Teakettle project, please contact Marissa Goodwin at email@example.com.
Go here more information about the field site.
There seems to be a misunderstanding in what is often referred to loosely as wildfire risk. Risk for anything is calculated by combining the probability or chance that an event occurs and the consequence of that event occurring. We do things to manage risk that can change either the chance that the event occurs, the consequence of the event occurring, or both. The COVID-19 vaccine is a perfect example of changing both, by decreasing the chance that you get COVID-19 and the consequence if you do (decreased severe illness).
In wildfire terms, I keep seeing news stories and quotes from elected leaders that forest management is going to reduce wildfire risk or, in the most poor representation of the concept, treatments will stop wildfires. In terms of the risk equation, the chance that a wildfire occurs is the result of having an ignition source when the vegetation and weather will support that ignition turning into a fire. The consequence of the fire depends on how and where the fire burns.
We have no shortage of ignitions on our flammable landscapes in the US. This year, in the western US, we have severe drought conditions that mean there is a greater chance that an ignition will cause vegetation to combust because dry vegetation is more flammable than wet vegetation. What we really care about though is the consequence of a wildfire occurring and this is where forest and vegetation management come into play.
As I have written about before (here and here), when you have more vegetation and it becomes drier, fires can become more impactful because they are releasing substantial amounts of energy that can lead to things like a fire creating its own weather. Managing vegetation reduces the chance that a fire creates its own weather because there is less energy stored in vegetation. Managing vegetation also helps create conditions that allow wildland firefighters to more easily protect homes and it changes the effects of the fire on the vegetation that is present on the landscape.
The basic fact is that we cannot exclude fire from our landscapes. We have plenty of ignitions and climate change is making the vegetation more flammable. We also have a surplus of vegetation in a number of areas because we have been excluding fire for decades. We are trying to change the risk with forest management by changing the way the fire burns on the landscape. We also need to work on making homes less flammable and managing vegetation in the wildland urban interface to help reduce risk, but that is a topic for another day.
When you hear or read about reducing wildfire risk, this is really about changing the way that fire behaves on the landscape. When you hear someone talk about forest management stopping fire, know that is incorrect and we cannot stop fire. Managing vegetation to change fire behavior is one of the solutions that we have at the local level for managing the risk of high-consequence wildfires.