A boreal ecosystem is an ecosystem with a subarctic climate in the Northern Hemisphere, roughly between latitude 60° to 70°N. Boreal forests are also known as the taiga, particularly in Europe and Asia.
The Boreal Ecosystem-Atmosphere Study (BOREAS) was a major international research program in the Canadian boreal forest. NASA sponsored the program, and most research took place between 1994 and 1996. Its primary goals were to determine how the boreal forest interacts with the atmosphere, how climate change will affect the forest, and how changes in the forest affect weather and climate.
The ecosystems that lie immediately to the south (in the Northern Hemisphere) of boreal zones are often called hemiboreal.
The Köppen symbols of boreal ecosystems are Dfc, Dwc, Dfd, and Dwd.