Rudolph and Friends Help Mitigate Warming Effect of Climate Change, Here's How

A new study revealed that reindeer could help mitigate climate change by simply reducing the height and abundance of shrubs on the Arctic Tundra through grazing.

The study, published in the journal Environmental Research Letters, showed that areas in the Arctic Tundra heavily grazed by reindeer experience increased levels of surface albedo, or the amount of shortwave radiation reflected by the Earth back into the space.

"Our results show that reindeer have a potential cooling effect on climate, by changing the summer albedo," said lead author Dr Mariska te Beest, from Umeå University in Sweden, in a press release. "Although the estimated differences might appear small, they are large enough to have consequences for the regional energy balance."

For the study, the researchers measured the abundance of vegetation, leaf area index, soil moistures, temperature levels and albedo levels of an area with four topographically-defined vegetation types that varied in shrub height and abundance. These measurements of albedo and vegetation characteristics taken in the field located in Reisadalen, Troms, Norway were then combined with land surface computer modeling.

Using vegetation trampling indicators and leftover dung, the researchers estimated the reindeer activities in the study area through the summer season.

The researchers found that grazing reindeer increases summer albedo by reducing shrub height, abundance and leaf area index. However, the beneficial effects of grazing reindeers vary according to their densities and how they affect the vegetation levels throughout the whole Tundra.

High densities of grazing reindeer were able change the vegetation across the Tundra by decreasing shrub abundance, resulting to corresponding shifts in leaf area index, canopy height and the amount of live green vegetation.

As the reduced height and abundance of shrub increases the summer albedo, the researchers observed a corresponding decrease in net radiation and latent and sensible heat fluxes. These decreases indicate that areas heavily grazed by reindeers absorbed less radiation from the sun.