Regions having a subarctic climate (also called boreal climate) are characterized by very cold winters, and brief, warm summers. This type of climate offers some of the most extreme seasonal temperature variations found on the planet: In winter, temperature can drop to −40°C (also −40°F) and in summer, the temperature may reach 30°C (86°F). The subarctic climate is a subset of the continental climate.

Vegetation in the subarctic climate is generally sparse, as only hardy species can survive the long winters and make use of the short summers. Agriculture is almost nonexistent, and confined to vegetables that can grow very quickly. Trees are mostly limited to ferns and evergreen conifers, as few broadleafed trees are able to survive the very low temperatures in winter; this type of forest is also known as taiga, a term which is sometimes applied to the climate found therein as well.