Vital Signs

The Arctic tundra biome occupies Earth’s northernmost landmasses and forms a “wreath” of treeless vegetation that encircles the Arctic Ocean. Arctic tundra ecosystems are strongly influenced by warming air temperatures, and thus have become a focal point of global environmental change.

Surface air temperatures (SAT) represent one of the strongest indicators of Arctic change over the last 50 years.

Snow covers the Arctic land surface (land areas north of 60° N) for up to 9 months each year, and influences the surface energy budget, ground thermal regime, and freshwater budget of the Arctic.

The Greenland ice sheet sits atop the world’s largest island and holds the equivalent of 7.4 m of potential sea level rise. Following a period of relative stability from the 1970s to early 1990s, the ice sheet began losing ice at an accelerating rate and has now experienced annual net ice loss every year since 1998.

Arctic sea ice is an important part of the climate system.

Summer sea surface temperatures (SST) in the Arctic Ocean are driven mainly by the amount of incoming solar radiation absorbed by the sea surface.

Autotrophic single-celled algae living in sea ice (ice algae) and water column (phytoplankton) are the main primary producers in the Arctic Ocean.

The Arctic tundra biome occupies Earth’s northernmost landmasses and forms a “wreath” of treeless vegetation that encircles the Arctic Ocean. Arctic tundra ecosystems are strongly influenced by warming air temperatures, and thus have become a focal point of global environmental change.

Arctic surface air temperature is an indicator of both regional and global climate change. Although there are year-to-year and regional differences in air temperatures, driven by natural variability, the magnitude, persistence, and Arctic-wide patterns of recent temperature increases are indicators of global climate change from increasing concentrations of atmospheric greenhouse gases. Warming atmospheric temperatures also act as a driver of Arctic changes in the ocean and on land. 

Snow covers the Arctic land surface (land areas north of 60° N) for up to 9 months each year, and influences the surface energy budget, ground thermal regime, and freshwater budget of the Arctic.