Climate zones in Iran, 1991 to 2020
Share of Iran's classified land in each Köppen-Geiger zone in 1991 to 2020. Zones under 0.05% are left out. The 2,246,557 map cells used cover 100% of the country's outline (about 1,622,637 km²).
By major group: B (arid) 80%, D (cold (continental)) 13%, C (temperate) 6.4%.
Iran has no single dominant climate. The biggest zone, BWh (hot desert), covers only 43% of its classified land in 1991 to 2020, followed by BSk (20%) and BSh (9.3%). 7 zones each cover 1% or more of it. In plain terms, hot desert means very dry and hot. Under the middle-of-the-road scenario (SSP2-4.5), 25% of its land is projected to be in a different zone by 2071 to 2099, with the biggest gain going to BWh (hot desert).
How Iran's zones have changed and may change
Each row compares a map with 1991 to 2020. "Share in a different zone" is the share of the country's area whose class is different from 1991 to 2020. Future rows are model projections under an emissions scenario, not forecasts.
| Map | Share in a different zone | Different major group | Biggest gain | Biggest loss |
|---|---|---|---|---|
| 1901 to 1930 (past) | 19% | 5.4% | BWh +6.6 percentage points | BWk -4 percentage points |
| 2071 to 2099, SSP1-2.6 (low emissions) | 18% | 5.9% | BWh +5 percentage points | BWk -4.5 percentage points |
| 2071 to 2099, SSP2-4.5 (middle of the road) | 25% | 7.7% | BWh +8.8 percentage points | BWk -6.5 percentage points |
| 2071 to 2099, SSP5-8.5 (high emissions) | 37% | 12% | BWh +13.3 percentage points | BSk -9.4 percentage points |
For the past row, the comparison runs the other way: the 1901 to 1930 map against 1991 to 2020.
Zone shares by map
| Zone | 1901 to 1930 | 1991 to 2020 | SSP1-2.6 (2071 to 2099) | SSP2-4.5 (2071 to 2099) | SSP5-8.5 (2071 to 2099) |
|---|---|---|---|---|---|
| BWh Hot desert | 36% | 43% | 48% | 52% | 56% |
| BSk Cold semi-arid (steppe) | 22% | 20% | 17% | 16% | 11% |
| BSh Hot semi-arid (steppe) | 7% | 9.3% | 10% | 12% | 16% |
| BWk Cold desert | 12% | 8.3% | 3.8% | 1.8% | 0.3% |
| Dsa Hot-summer continental with dry summer | 8.9% | 8% | 8.3% | 6.8% | 3.9% |
| Csa Hot-summer Mediterranean | 5.4% | 6.1% | 9.7% | 11% | 13% |
| Dsb Warm-summer continental with dry summer | 7.7% | 4.9% | 2.8% | 1.5% | 0.4% |
| Cfa Humid subtropical | 0.1% | 0.3% | 0.2% | 0.1% | - |
| Dfb Warm-summer humid continental | 0.3% | 0.2% | 0.1% | - | - |
| Dsc Subarctic with dry summer | 0.3% | 0.2% | - | - | - |
| Csb Warm-summer Mediterranean | 0.1% | - | - | - | - |
Percentages are of the country's classified land in each map. A dash means under 0.05%.
Cities in Iran and their climate zones
| City | 1991 to 2020 | 2071 to 2099, SSP2-4.5 |
|---|---|---|
| Tehran | BSk Cold semi-arid (steppe) | BSh Hot semi-arid (steppe) |
| Mashhad | BSk Cold semi-arid (steppe) | BSk Cold semi-arid (steppe) |
| Isfahan | BWk Cold desert | BWh Hot desert |
| Karaj | BSk Cold semi-arid (steppe) | Csa Hot-summer Mediterranean |
| Tabriz | BSk Cold semi-arid (steppe) | BSk Cold semi-arid (steppe) |
| Shiraz | BSh Hot semi-arid (steppe) | BSh Hot semi-arid (steppe) |
| Qom | BWh Hot desert | BWh Hot desert |
| Ahvaz | BWh Hot desert | BWh Hot desert |
| Kermanshah | Csa Hot-summer Mediterranean | Csa Hot-summer Mediterranean |
| Rasht | Cfa Humid subtropical | Csa Hot-summer Mediterranean |
Zones found in Iran
Data: Beck et al. (2023), CC BY 4.0; country outlines from Natural Earth. In 1901 to 1930 the most common zone was BWh. See data sources and licences.