The objective of this website is to present recent indicators that describe the present state of the Arctic climate and ecosystem in an accessible, understandable, and credible historical context. A summary of changes are listed in the Table of Indicators.

The Arctic is a vast, ice-covered ocean that is surrounded by tree-less, frozen land, which is often covered with snow and ice. The rigors of this harsh environment are a challenge to living, working and performing research in the Arctic. None the less, the Arctic is an ecosystem that teems with life including organisms living in the ice, fish and marine mammals living in the sea, birds, land animals such as wolves, caribou and polar bears, and human societies.

The Arctic has been changing in the last 30 years, as noted throughout this website. Some of the clearest indicators of this change are shown below: the warming of spring temperatures in Alaska, the warming of winter temperatures in N Europe, the loss of sea ice area in the central Arctic, and the conversion of tundra to wetlands and shrub lands in E. Siberia and NW Canada and Alaska. These changes in physical conditions also have impacted marine and terrestrial ecosystems. To see more details, click on the topics in the navigation panel on the left.

Surface air temperature anomaly for Barrow, Alaska in April and for Tromso, Norway in Winter. An anomaly is the difference from a long term average value for the same season. For Barrow, note the temperatures from 1990 onward are often more than 4 degrees above historical values. For Tromso, note the continuation of warm temperatures in the 1990's following a period of cold temperatures in the late 1970's and 1980's.

Data from Global Historical Climate Network (GHCN). Updates made using the World Monthly Surface Climatology dataset (ds570.0) or, in some instances, from the NCDC Summary of the Day data. For more information see Surface Temperatures.