Emerging Anthropogenic Influences on the Southcentral Alaska Temperature and Precipitation Extremes and Related Fires in 2019

The late-season extreme fire activity in Southcentral Alaska during 2019 was highly unusual and consequential. Firefighting operations had to be extended by a month in 2019 due to the extreme conditions of hot summer temperature and prolonged drought. The ongoing fires created poor air quality in the region containing most of Alaska’s population, leading to substantial impacts to public health. Suppression costs totaled over $70 million for Southcentral Alaska.

This study’s main goals are to place the 2019 season into historical context, provide an attribution analysis, and assess future changes in wildfire risk in the region. The primary tools are meteorological observations and climate model simulations from the NCAR CESM Large Ensemble (LENS). The 2019 fire season in Southcentral Alaska included the hottest and driest June–August season over the 1979–2019 period. The LENS simulation analysis suggests that the anthropogenic signal of increased fire risk had not yet emerged in 2019 because of the CESM’s internal variability, but that the anthropogenic signal will emerge by the 2040–80 period. The effect of warming temperatures dominates the effect of enhanced precipitation in the trend towards increased fire risk.

Purpose

This study’s main goals are to place the 2019 season into historical context, provide an attribution analysis, and assess future changes in wildfire risk in the region.

Lineage

The raw data presented [UB2] in this study are openly available in their respective repositories. [Figure 2 was prepared with data from NASA. We acknowledge the use of data and/or imagery from NASA's Fire Information for Resource Management System (FIRMS) (https://earthdata.nasa.gov/firms), part of the NASA Earth Observing System Data and Information System (EOSDIS). NRT VIIRS 375 m Active Fire product VNP14IMGT distributed from NASA FIRMS. Available on-line: https://earthdata.nasa.gov/firms]. doi:10.5067/FIRMS/VIIRS/VNP14IMGT_NRT.002]; [Figure 4 was prepared using Air quality data from the EPA Air Quality Program available on-line: https://www.epa.gov/outdoor-air-quality-data]; [Figure 5 data was provided by NOAA National Centers for Environmental information, Climate at a Glance: Divisional Mapping at https://www.ncdc.noaa.gov/cag/]; [Figure 6 and 7 were prepared using data from Mesowest at: https://akff.mesowest.org/]; [Figure 8 data are available at https://zenodo.org/record/3626193#.YAHgsOBRdTY]; [Figure 9 and 10 were prepared using ERA5 data available at: https://www.ecmwf.int/en/forecasts/datasets/reanalysis-datasets/era5]; [Figure 11–15 were prepared using NCAR CESM LENS data available at on the Earth System Grid using guidance at: https://www.cesm.ucar.edu/projects/community-projects/LENS/data-sets.html]

Data and Resources

This dataset has no data

Additional Info

Field	Value
Last Updated	September 29, 2021, 09:30 (AKDT)
Created	June 3, 2021, 12:08 (AKDT)
Start Date	2019-06
End Date	2019-07