Climate zones in Sri Lanka, 1991 to 2020
Share of Sri Lanka's classified land in each Köppen-Geiger zone in 1991 to 2020. Zones under 0.05% are left out. The 77,067 map cells used cover 99% of the country's outline (about 65,581 km²).
By major group: A (tropical) 99%, C (temperate) 1.5%.
Aw, tropical savannah, is the main climate of Sri Lanka, covering 54% of its classified land in 1991 to 2020, with Af (tropical rainforest) next at 29%. In plain terms, tropical savannah means hot all year, with a clear dry season. Under the middle-of-the-road scenario (SSP2-4.5), 10% of its land is projected to be in a different zone by 2071 to 2099, with the biggest gain going to Am (tropical monsoon).
How Sri Lanka'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) | 20% | 1% | Aw +9.3 percentage points | Am -5.3 percentage points |
| 2071 to 2099, SSP1-2.6 (low emissions) | 9.5% | 0.4% | Am +5.7 percentage points | Aw -4 percentage points |
| 2071 to 2099, SSP2-4.5 (middle of the road) | 10% | 0.7% | Am +7.3 percentage points | Aw -4.5 percentage points |
| 2071 to 2099, SSP5-8.5 (high emissions) | 13% | 1.2% | Am +10 percentage points | Aw -6.2 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) |
|---|---|---|---|---|---|
| Aw Tropical savannah | 44% | 54% | 50% | 49% | 47% |
| Af Tropical rainforest | 32% | 29% | 28% | 27% | 26% |
| Am Tropical monsoon | 21% | 16% | 22% | 23% | 26% |
| Cfb Temperate oceanic | 2.5% | 1.5% | 1.1% | 0.8% | 0.3% |
Percentages are of the country's classified land in each map. A dash means under 0.05%.
Cities in Sri Lanka and their climate zones
| City | 1991 to 2020 | 2071 to 2099, SSP2-4.5 |
|---|---|---|
| Colombo | Af Tropical rainforest | Af Tropical rainforest |
Zones found in Sri Lanka
Data: Beck et al. (2023), CC BY 4.0; country outlines from Natural Earth. In 1901 to 1930 the most common zone was Aw. See data sources and licences.
