Climate file

The climate file

Sourced facts about the world’s climates, topic by topic. Every fact links to its source, checked 2 Nov 2026.

What is climate?

Climate is the general weather over a long period. It can include rainfall, temperature, snow or any other weather condition. [source]
A region’s climate is usually worked out over a period of 30 years. [source]
Weather is the state of the air at one place over a short time. Climate is the average over a long period, 30 years or more, for a larger area. [source]

Climate zones are areas with distinct climates. They can match weather patterns, latitude, or communities of plants and animals. [source]
Climate zones can even help farmers and gardeners work out which plants will grow best where they live. [source]
The Köppen system, one of the most widely used, sorts the world’s climates into five groups: tropical (A), dry (B), temperate (C), continental (D) and polar (E). [source]
Wladimir Köppen (1846–1940) was a German meteorologist and climatologist, best known for mapping the climate regions of the world. [source]
Köppen wanted his climate boundaries to match the vegetation zones (biomes) that were being mapped for the first time in his lifetime. [source]

Climate change is the long-term shift in average weather patterns across the world. [source]
In the 11,000 years before the Industrial Revolution, the world’s average temperature was stable at around 14 °C. [source]
Since the Industrial Revolution, the planet’s average temperature has risen by around 1.1 °C. [source]
Changes in Earth’s climate since the mid-20th century are driven by human activities, particularly burning fossil fuels, which adds heat-trapping greenhouse gases to the atmosphere. [source]
Global warming is the long-term heating of Earth’s surface seen since the pre-industrial period, between 1850 and 1900. [source]

A desert is any large, extremely dry area of land with sparse vegetation. [source]
In the Sahara, the ground surface has been measured as hot as 78 °C, hotter than the air above it. [source]
The largest area of temperate (cold-winter) desert lies in Central Asia. [source]
In Chile’s Atacama Desert, a cold ocean current makes fog and low stratus cloud, but no rain. [source]
The interior of the Atacama Desert receives the highest solar radiation in the world. [source]

Tropical rainforests grow in wet lowlands and uplands near the Equator, with high temperatures all year. [source]
Rainfall in a tropical rainforest is usually more than 1,800 mm a year, with little change from season to season. [source]
The biggest tropical rainforests are in Southeast Asia, tropical South and Central America (especially the Amazon basin) and West and Central Africa. [source]

The world’s lowest recorded temperature, −89.2 °C, was measured at Vostok Station in Antarctica on 21 July 1983. [source]
Antarctica counts as one of the world’s great deserts: its polar plateau gets only about 50 mm of precipitation a year. [source]
Tundra is a treeless biome in cold places, north of the Arctic Circle or above the tree line on high mountains. [source]
The Finns called their treeless northern lands the tunturi. [source]

A monsoon is a wind system that changes direction with the seasons, blowing for about six months from the northeast and six months from the southwest. [source]
Monsoon winds usually blow from sea to land in summer and from land to sea in winter. [source]
In India, the wet southwest monsoon lasts from about mid-June to early October. [source]

An ice age is any period when thick ice sheets cover vast areas of land. [source]
At the peak of the last glacial period, about 29,000 to 19,000 years ago, ice sheets covered about 8% of Earth’s surface and sea levels were about 125 metres lower than today. [source]
A smaller cooling event called the Little Ice Age took place between 1300 and 1850 CE. [source]

We have seasons because Earth’s axis is tilted by about 23.5°, so each hemisphere gets different amounts of sunlight through the year. [source]
Earth’s distance from the Sun changes a little over a year, but it is not what causes the seasons. [source]

El Niño is the appearance, every few years, of unusually warm ocean water along the tropical west coast of South America. [source]
Peruvian fishermen named it El Niño, after the Christ Child, because the warm water arrived around Christmas. [source]
El Niño events come irregularly, every two to seven years. [source]

A cloud is a visible mass of water droplets, ice crystals, or both, floating in the air. [source]
Cloud droplets are tiny: about 0.01 mm across. [source]
Cirrus, cirrocumulus and cirrostratus are high clouds, found about 5 to 13 km above the ground, and are made only of ice crystals. [source]
A cloud at ground level is called fog. [source]

Figures are the sources’ own, and climate records are updated as new measurements come in.

Ad · affiliate link

For the garden, the classroom or the bookshelf: Rain gauges · Weather stations for kids · Cloud guides · Climate books for kids · Globes · Outdoor thermometers. These are Amazon UK search links, not endorsements of particular products. As an Amazon Associate I earn from qualifying purchases.