What a Cwb climate is like
Cwb Subtropical highland (dry winter). Cooler than the tropical lowlands around it, usually because of altitude. Summers are warm rather than hot, and the rain falls mostly in summer.
The rules behind the code, in plain English:
- Temperate (coldest month between 0 °C and 18 °C).
- Dry winter: the driest winter month gets less than a tenth of the rain of the wettest summer month.
- Warm summer: the warmest month is under 22 °C, and at least four months are above 10 °C.
Dataset wording: "Temperate, dry winter, warm summer". In the maps of Beck et al. (2023) the class is written: C: Not B and Thot > 10 and 0 < Tcold < 18; w: Pwdry < Pswet/10; b: Not a and Tmon10 >= 4.
Subtropical highland climate with a dry winter is mild all year, because height cools what would otherwise be a hot tropical or subtropical place. Summers are wet and pleasant rather than hot, and winters are dry and cool, often with cold nights. It suits coffee, tea, maize and vegetables, and many towns grow at these altitudes. Homes need a way to keep warm on winter nights, and a light jacket is useful all year.
How much of the world is Cwb?
- 1.2%of the world's land outside Antarctica, 1991 to 2020
- 1,594,138 km²area, 1991 to 2020
- 550cities of 15,000 or more people (GeoNames) have this climate now
In 1901 to 1930 it covered 1.5% of that land, so its area then was 24.52% larger than in 1991 to 2020.
How the Cwb area is projected to change by 2071 to 2099
These figures compare the area of Cwb 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) | 1.5% | +24.52% |
| 1991 to 2020 (now) | 1.2% | - |
| 2071 to 2099, SSP1-2.6 (low emissions) | 0.9% | -26.87% |
| 2071 to 2099, SSP2-4.5 (middle of the road) | 0.7% | -40.52% |
| 2071 to 2099, SSP5-8.5 (high emissions) | 0.5% | -55.98% |
Shares are of land outside Antarctica. A negative change means the zone shrinks.
What happens to today's Cwb land
Of the land that is Cwb in 1991 to 2020, this is how much stays Cwb and where the rest ends up in 2071 to 2099, by scenario:
| Scenario (2071 to 2099) | Stays Cwb | Where the rest goes (biggest first) |
|---|---|---|
| SSP1-2.6, low emissions | 65% | Cwa (23%), Aw (4.7%), Cfb (2.7%), BSk (1.8%), BSh (0.9%) |
| SSP2-4.5, middle of the road | 48% | Cwa (32%), Aw (12%), BSh (2.2%), BSk (2.2%), Cfb (1.9%) |
| SSP5-8.5, high emissions | 26% | Cwa (40%), Aw (21%), BSh (7.5%), BSk (1.8%), Am (1.7%) |
Looking back, 92% of today's Cwb land was also Cwb in 1901 to 1930. The rest was Cfb (2.2%), BSk (1.4%), Cwa (1.1%), Dwb (0.9%), ET (0.8%).
Where Cwb is found
The countries with the most Cwb land in 1991 to 2020:
| Country | Area | Share of all Cwb | Share of the country |
|---|---|---|---|
| China | 310,151 km² | 19% | 3.3% |
| Mexico | 230,371 km² | 14% | 12% |
| South Africa | 162,658 km² | 10% | 13% |
| Ethiopia | 87,317 km² | 5.5% | 7.7% |
| Bolivia | 86,063 km² | 5.4% | 7.9% |
| Madagascar | 81,972 km² | 5.1% | 14% |
| Tanzania | 74,476 km² | 4.7% | 7.9% |
| Peru | 66,694 km² | 4.2% | 5.2% |
Places with a Cwb climate today
The biggest cities in the 1991 to 2020 map that sit in Cwb (at most two per country):
- Mexico City, Mexico
- Johannesburg, South Africa
- Kunming, China
- Addis Ababa, Ethiopia
- Iztapalapa, Mexico
- Soweto, South Africa
- Harare, Zimbabwe
- Qujing, China
- Antananarivo, Madagascar
- Guatemala City, Guatemala
- Cochabamba, Bolivia
- Lubango, Angola
Other temperate climates (group C)
Frequently asked questions
What does Cwb mean in the Köppen climate classification?
Temperate (coldest month between 0 °C and 18 °C). Dry winter: the driest winter month gets less than a tenth of the rain of the wettest summer month. 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 (C, temperate) and the letters after it say more about rain and temperature.
What is a subtropical highland (dry winter) climate like?
Mild all year, with a dry winter. Cooler than the tropical lowlands around it, usually because of altitude. Summers are warm rather than hot, and the rain falls mostly in summer.
How much of the world has a Cwb climate?
1.2% of the world's land outside Antarctica was Cwb in 1991 to 2020, about 1,594,138 km² (Beck et al. 2023, 1 km maps).
Will the Cwb climate zone grow or shrink?
Under the middle-of-the-road scenario (SSP2-4.5), the area of Cwb in 2071 to 2099 is 40.52% smaller 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.