A biome is one of Earth's major natural environments, defined by its climate, plants, and animals. Earth has around ten major biomes that together cover every patch of land and water on the planet, from the frozen tundra of the Arctic to the warm coral reefs of the tropics.
- Major Biomes13across land, freshwater and sea
- Coldest BiomeArctic Tundradown to -50 °C in winter
- Hottest BiomeHot Desertup to 55 °C in shade
- Wettest BiomeTropical Rainforestover 2,000 mm rain a year
- Driest BiomeCold Desertunder 250 mm rain a year
- Biggest by AreaMarinecovers 71% of Earth's surface
How much rain does each biome get?
Annual rainfall is the single biggest reason biomes differ. Compare a few:
Rainforests get more than ten times as much rain as deserts. That single difference shapes which plants can grow, which animals can live there, and even how the soil forms.
What is a biome?
A biome is a large region of the world that has its own climate (the long-term pattern of weather), its own kinds of plants, and its own kinds of animals. Two places on opposite sides of the world can belong to the same biome if their climate matches up. The savanna of Africa and the grasslands of Australia, for example, share a biome even though they sit on different continents.
How biomes form
Climate is the engine. The amount of sunlight, rain, heat and cold a place gets decides what kind of life can survive there. Hot and wet near the equator gives you rainforest. Hot and dry inland gives you desert. Cold and dry near the poles gives you tundra. Once plants take hold, animals follow, and the biome locks in over thousands of years.
Land biomes
The main land biomes you will meet on Factsmania are deserts, rainforests, mountains, grassland, savanna, taiga (boreal forest), temperate forest, chaparral, wetland, and the cold tundra near the two poles.
Water biomes
Water biomes cover even more of the planet than land biomes. The marine biome includes all of Earth's oceans and seas, while the freshwater biome covers rivers, lakes, ponds and wetlands.
Why biomes matter
Biomes are not just labels on a map. They are working systems that produce the air we breathe, the food we eat, and the fresh water we drink. Damage to one biome (chopping down rainforests, draining wetlands, polluting oceans) ripples out and affects the whole planet, including the climate where you live.
Deeper dive: biomes vs ecosystems vs habitats
You will hear three similar-sounding words a lot in nature lessons, and they fit together like nested boxes.
- Biome is the biggest. A whole region with the same climate and the same broad types of life. The rainforest biome covers parts of three different continents.
- Ecosystem is medium. A specific community of plants, animals, fungi and microbes plus the non-living things (soil, water, air) they share. One stretch of Amazon rainforest can contain many different ecosystems.
- Habitat is the smallest. The particular place where one species lives. A jaguar's habitat is the parts of the rainforest where it hunts.
So: many habitats make up an ecosystem, many ecosystems make up a biome, and many biomes make up the planet.
Pick any biome from the list below to find out more.