Group D

Continental climates

Far from the sea: hot summers, hard winters, and a lot of trees.

A satellite view of northern New England in autumn, with forests in patches of red, orange and green — Autumn colours across the forests of northern New England, seen by a NASA satellite in 2022.Picture: MODIS Land Rapid Response Team, NASA GSFC, Public domain, Commons

Away from the sea

Continental climates are like temperate ones but with bigger extremes, because they sit far inland, away from the calming effect of the sea. Met Office: Climate zones

Rule for D: warmest month 10 °C or more, coldest month −3 °C or lower. Encyclopaedia Britannica: Köppen climate classification

Continental climates are mostly in the interiors of Canada and Russia, with some in the northern USA. Met Office: Climate zones

D climates are almost all in the northern hemisphere, because the southern hemisphere has hardly any land at those latitudes. Encyclopaedia Britannica: humid continental climate

Two bars comparing the gap between summer and winter temperatures: a short bar for a marine west coast, about 10 to 15 degrees, and a bar about twice as tall for a continental interior at the same latitude — Our drawing comparing the summer-to-winter gap by the sea and deep inland.Drawing: our own

On marine west coasts the yearly temperature range is only about 10–15 °C, roughly half that of the continental interior at the same latitude. Encyclopaedia Britannica: marine west coast climate

Humid continental (Dfa, Dfb, Dwa, Dwb)

Humid continental climates have big swings between hot summers and cold winters. Encyclopaedia Britannica: humid continental climate They are found between 30° and 60° north in central and eastern North America and Asia. Encyclopaedia Britannica: humid continental climate

Humid continental climates are Dfa, Dfb, Dwa and Dwb. Encyclopaedia Britannica: humid continental climate

Snow often lies continuously for one to four months in many parts. Encyclopaedia Britannica: humid continental climate The frost-free season lasts from under 150 to about 200 days a year. Encyclopaedia Britannica: humid continental climate

A wide, rolling tallgrass prairie under a pale sky — Konza Prairie, a tallgrass prairie near Manhattan, Kansas, photographed in 1975.Picture: Patricia DuBose Duncan, Public domain, Commons

Subarctic and the taiga (Dfc, Dfd, Dwc, Dwd)

The continental subarctic climate is Dfc, Dfd, Dwc and Dwd. Encyclopaedia Britannica: Köppen climate classification

The taiga, or boreal forest, is the great northern forest of cone-bearing evergreen trees, with long winters. Encyclopaedia Britannica: taiga Taiga is Russian for “land of the little sticks”. Encyclopaedia Britannica: taiga

The taiga covers about 17 per cent of Earth’s land, in a belt around the far north. Encyclopaedia Britannica: taiga

Its trees are mostly pine, spruce, larch and fir, and they reach further north than any other trees on Earth. Encyclopaedia Britannica: taiga

Thin, dark spruce trees standing in deep, untrodden snow — Black spruce forest under snow in Alaska.Picture: BLM Alaska, Public domain, Commons

d: the coldest month is below −38 °C. Encyclopaedia Britannica: Köppen climate classification

Next: polar and mountain climates →