As climate warming brings more wildfire to the North, scientists and citizens wonder how the landscape will be transformed. Will forests continue their 2000’s-era trend toward less spruce and more hardwoods, catalyzed by larger fires and more frequent burning? If so, that might slow down the trend for larger and more intense fires. However, will hotter summers with more effective drying lead to increased fire re-entry into the early successional hardwoods, making them less strategic barriers for fire protection? A research team modeling the former question just unveiled an interactive web tool to model forest changes under various future climate scenarios (Feb. 1 webinar recording available HERE). With the new web tool, funded by JFSP, Paul Duffy and Courtney Schultz will be working with fire managers in Alaska to look at fire occurrence and cost in the future. Try it for yourself at http://uasnap.shinyapps.io/jfsp-v10/
How do you know whether forest fires or factories and diesel generators are responsible for Black Carbon or CO2 in the air or deposited in icefields? An experiment called CARVE (Carbon in Arctic Reservoirs Vulnerability Experiment) led by Chip Miller of the NASA Jet Propulsion Laboratory was conducted in Alaska’s airspace and some results just published explain how the source can be identified. The combustion of woody biomass (or more importantly in Alaska–layers of compacted dead moss and organic soil) liberates primarily carbon deposited since World War II into CO2. That modern post-bomb carbon contains traces of radioactive carbon (Δ14C) in contrast to fossil fuels, deposited in prehistoric times, which have none.
CARVE: Sherpa aircraft flew sensors over fires in Alaska in 2013 to measure atmospheric concentrations of gases.
During the CARVE experiment, Sherpa aircraft flew sensors to measure atmospheric concentrations of CH4, CO2, and CO and parameters that control gas emissions (i.e. soil moisture, freeze/thaw state, surface temperature). They directly flew over some fires (including fires near Fairbanks and Delta) to measure the “fingerprint” concentrations of isotopes released by typical boreal burning. Mouteva et al. (2015) published findings that showed most of the C in the summer skies over Alaska in 2013 was indeed attributable to forest fires and the age of the biomass converted to black carbon averaged about 20 years (range 11-47 yrs). The authors also explore using the carbon isotope “fingerprint” of fires to estimate the average depth of consumption–since Δ14C increases with depth from the surface moss to the mesic horizon. Pooled results of radioactive isotope fractions yielded an average depth of burn of about 8 inches for the 2013 Alaska fires–a result that may vary depending on fuel conditions. Burn severity, expressed as depth of consumption, is a hot topic among agencies and land managers because it drives ecological response to burning as well as vegetation changes which may come with the hypothesized climate-driven increased boreal burning.
Citation: Mouteva, G. O., et al. (2015), Black carbon aerosol dynamics and isotopic composition in Alaska linked with boreal fire emissions and depth of burn in organic soils, Global Biogeochem. Cycles: 29, doi:10.1002/2015GB005247.
This presentation and MANY MORE available on fuel moisture sampling, remote sensing validation of FWI, new remote sensing tools for fire detection and growth modeling, using dataloggers on soil moisture probes to track fuel moisture changes, and the seasonality of CFFDRS, to name a few.
It’s hard to say what impact the recession of permafrost in the northern half of Alaska will have on fire regime. One could presume there should be more organic moss and duff material available for combustion during the summer, which is likely to have implications for tundra fire extent and severity. Warmer permafrost has also been linked to more extensive retrogressive thaw slumps–a kind of thermokarst which have been seen after tundra fire in ice-rich areas (photo). If you can make it, Dr. Romanovsky’s talk “Evidence of recent warming and thawing of permafrost in the Arctic and sub-Arctic,“ with updates on his extensive grid of permafrost monitoring wells up and down Alaska should be very interesting. The talk is Oct 23 at Elvey Auditorium, University of Alaska-Fairbanks, at 4 pm ADT. See the summary flyer <<HERE>>.
UAF scientist Dan Mann examines fire-induced thermokarst 3 years after Anaktuvuk River fire in arctic Alaska.
UNIversity FORmation Mission 1–microsatellite designed by Hokkaido University for wildfire management (photo: Koji Nakau)
Hokkaido University (HU) is one of the world leaders in developing new earth-observing space technology. Dr. Koji Nakau leads their wildfire remote sensing applications team. He’s working with various partners—including UAF—on new satellite-derived products delivered to wildland fire managers in Alaska and around the world. They are especially excited about the May 24th (2014) launch of a rocket carrying ALOS-2 (Advanced Land Observing Satellite) which is also carrying a couple microsatellites with sensors specifically designed by his team to detect wildfire signatures. In addition to improving real-time operational support, satellite data is analyzed in support of wildfire propagation modeling, smoke transport, fuels estimates, and post-fire ecology.