Do Burned Boreal Landscapes Hold Less Snow?

Fire is an important part of the boreal forest ecosystem, and how it burns affects every bit of the forest, but little is known about boreal fire impacts on snow. Snowfall and snowmelt differences in burned and unburned forest in Alaska were examined over three winters (2016-2017, 2017-2018, and 2018-2019). Data were collected by installing two cameras (in burned and unburned sites) that took two photos per day, aimed at PVC pipes with five cm increments marked on them. From more than 2,200 photos at each site, daily snow depths were estimated and recorded for the burned and unburned sites, and a scatterplot showing the mean difference for each year of snowfall was created. Overall, the burned forest's snow was shallower than the unburned forest. The snow levels usually rose and fell at the same time but were almost never the same depth, the exception being when there was no snow to measure. The sites never melted out on the same date; snow lingered a few days at the unburned site. These results show that burned forest does not hold as deep snow as unburned forest. It could have to do with the amount of sunlight and wind allowed to reach the snow. Burned trees do not provide as much shade as live trees. Also, wind speeds are likely higher where there are no branches with needles on burned trees, which allows larger gusts of wind. This research is significant because it shows how snowfall differs with disturbance and how the amount of snow changes from year to year.