Greening of Svalbard

In a new study, researchers confirm that climate change is affecting vegetation – Svalbard is getting greener.

Record summers lead to increased plant growth

Researchers from NORCE, UiT The Arctic University of Norway, Eurac Research, and the University of Cambridge have studied how climate change affects vegetation in Svalbard. They have examined daily satellite data back to the year 2000. The results show that plant growth in Svalbard has increased significantly during this period. Summer temperatures have also increased substantially.

Senior researcher Stein Rune Karlsen at NORCE explains the development:

– Plant growth is closely linked to summer temperatures. In recent years there have been significant changes in the other seasons in Svalbard, and now the summers are getting warmer. A new record in plant growth was first set in 2016, but that record was shattered in 2018. Growth was even higher in 2020, and a new clear record was set in 2022. The last two summers have yet to be measured with satellite data, but it is likely that further new records have been set.

Karlsen points out that July 2023 in Longyearbyen was record warm. The summer of 2024 also recorded temperatures well above normal with record-warm June and August. This indicates very high plant growth in the last two years as well.

Clear connection between plant growth and sea ice extent

The researchers compared satellite data with daily temperature data from 11 meteorological stations. Summer temperatures are extremely important for Arctic (and especially High Arctic) plant growth, and in Svalbard, there is a clear connection between measurements of vegetation growth and temperatures in June and July.

Some areas show increased plant growth, while others show less response. The study has identified a link between plant growth and sea ice extent. The unusually rapid warming of the northern Barents Sea is due to a strong decline in sea ice.

The researchers also observe local differences in plant growth. The permafrost is thawing, leading to larger areas of water accumulation that impact growth. In some places, reindeer and geese graze, making it difficult to measure the actual amount of plant growth in the area. Additionally, it is uncertain what happens in moss tundra in some areas, as moss-dominated regions are difficult to measure with satellites.

– The greatest increase in plant growth is in eastern Svalbard, on Edgeøya and Barentsøya. There areas have experienced the largest increase in temperatures as there is almost no sea ice left east of Svalbard in the summer. A rough estimate is that there is now about 100,000 tons more dry weight of plants for the whole of Svalbard compared to the cold summer of 2008. The summer of 2008 was one of the last years when sea ice covered the sea areas east of Svalbard for most of the summer, says Karlsen.