What a Dfb climate is like
Dfb Warm-summer humid continental. A forest climate with four distinct seasons and a cold, snowy winter, but warm summers.
The rules behind the code, in plain English:
- Cold (coldest month at or below 0 °C).
- No dry season (neither a dry summer nor a dry winter as defined above).
- Warm summer: the warmest month is under 22 °C, and at least four months are above 10 °C.
Dataset wording: "Cold, no dry season, warm summer". In the maps of Beck et al. (2023) the class is written: D: Not B and Thot > 10 and Tcold <= 0; f: Not Ds or Dw; b: Not a and Tmon10 >= 4.
Warm-summer humid continental climate has warm summers and cold, snowy winters, with rain all year. The four seasons are clear, with bright autumn colour and deep winter snow. Mixed forest, wheat, potatoes and dairy farming are typical. Houses are built with strong insulation and heating, and people change their clothes with the season.
How much of the world is Dfb?
- 7.5%of the world's land outside Antarctica, 1991 to 2020
- 10,174,742 km²area, 1991 to 2020
- 2,483cities of 15,000 or more people (GeoNames) have this climate now
In 1901 to 1930 it covered 6.7% of that land, so its area then was 11.27% smaller than in 1991 to 2020.
How the Dfb area is projected to change by 2071 to 2099
These figures compare the area of Dfb in each future map with 1991 to 2020. They come from the Beck et al. (2023) model projections under three emissions scenarios. They show what the scenarios imply, not what will happen.
| Map | Share of land | Change in area vs 1991 to 2020 |
|---|---|---|
| 1901 to 1930 (past) | 6.7% | -11.27% |
| 1991 to 2020 (now) | 7.5% | - |
| 2071 to 2099, SSP1-2.6 (low emissions) | 8.2% | +8.89% |
| 2071 to 2099, SSP2-4.5 (middle of the road) | 8.1% | +7.59% |
| 2071 to 2099, SSP5-8.5 (high emissions) | 5.4% | -28.8% |
Shares are of land outside Antarctica. A negative change means the zone shrinks.
What happens to today's Dfb land
Of the land that is Dfb in 1991 to 2020, this is how much stays Dfb and where the rest ends up in 2071 to 2099, by scenario:
| Scenario (2071 to 2099) | Stays Dfb | Where the rest goes (biggest first) |
|---|---|---|
| SSP1-2.6, low emissions | 76% | Dfa (18%), Cfb (3.3%), Cfa (1.5%), BSk (1%) |
| SSP2-4.5, middle of the road | 55% | Dfa (33%), Cfa (5.3%), Cfb (4.2%), BSk (2.3%) |
| SSP5-8.5, high emissions | 8.6% | Dfa (60%), Cfa (20%), BSk (7%), Cfb (3.3%) |
Looking back, 74% of today's Dfb land was also Dfb in 1901 to 1930. The rest was Dfc (24%), Dwb (0.6%).
Where Dfb is found
The countries with the most Dfb land in 1991 to 2020:
| Country | Area | Share of all Dfb | Share of the country |
|---|---|---|---|
| Russia | 3,199,283 km² | 31% | 19% |
| Canada | 2,627,516 km² | 26% | 27% |
| United States | 1,320,840 km² | 13% | 14% |
| Kazakhstan | 826,323 km² | 8.1% | 31% |
| Ukraine | 348,750 km² | 3.4% | 61% |
| Poland | 280,191 km² | 2.8% | 90% |
| Belarus | 206,636 km² | 2% | 100% |
| Sweden | 161,126 km² | 1.6% | 36% |
Places with a Dfb climate today
The biggest cities in the 1991 to 2020 map that sit in Dfb (at most two per country):
Other cold (continental) climates (group D)
- Dsa Hot-summer continental with dry summer
- Dsb Warm-summer continental with dry summer
- Dsc Subarctic with dry summer
- Dsd Subarctic with dry summer and very cold winter
- Dwa Hot-summer continental with dry winter
- Dwb Warm-summer continental with dry winter
- Dwc Subarctic with dry winter
- Dwd Subarctic with dry winter and very cold winter
- Dfa Hot-summer humid continental
- Dfc Subarctic (boreal)
- Dfd Subarctic with very cold winter
- All 30 zones
Frequently asked questions
What does Dfb mean in the Köppen climate classification?
Cold (coldest month at or below 0 °C). No dry season (neither a dry summer nor a dry winter as defined above). Warm summer: the warmest month is under 22 °C, and at least four months are above 10 °C. The code is a short way of writing that: the first letter is the major group (D, cold (continental)) and the letters after it say more about rain and temperature.
What is a warm-summer humid continental climate like?
Warm summers and cold, snowy winters, with rain all year. A forest climate with four distinct seasons and a cold, snowy winter, but warm summers.
How much of the world has a Dfb climate?
7.5% of the world's land outside Antarctica was Dfb in 1991 to 2020, about 10,174,742 km² (Beck et al. 2023, 1 km maps).
Will the Dfb climate zone grow or shrink?
Under the middle-of-the-road scenario (SSP2-4.5), the area of Dfb in 2071 to 2099 is 7.59% larger than in 1991 to 2020. This is a model projection, not a forecast, and it differs under other scenarios (see the table on this page).
Data: Beck et al. (2023), CC BY 4.0. See data sources and licences. Köppen-Geiger classes describe long-term averages, not weather.