Alpine tundra

Alpine tundra is a special kind of area found high up in mountains around the world. Because it is so high, the climate there is very cold and windy, which makes it too tough for trees to grow. This is why alpine tundra looks very different from forests—you won’t find tall trees there, only low, tough plants that can handle the cold.

These areas are found on mountains everywhere, from Europe to Asia and the Americas. The plants in alpine tundra, like small shrubs, stay close to the ground to stay safe from the strong winds. The cold conditions are caused by the air getting colder as it moves up the mountain, a process called adiabatic cooling.

Alpine tundra changes as you move down the mountain. Near the top, you might find snow and ice that stay all year long. Lower down, the climate gets a little warmer, and you can find stunted trees called krummholz before the area turns into a full forest below what is called the tree line.

Geography

Alpine tundra is found on mountains at very high altitudes all around the world. You can see it in places like the North American Cordillera, the Appalachian Mountains, the Alps, the Himalaya, and many other mountain ranges.

These high mountain areas are often rugged with rocky peaks and steep slopes. Some parts, however, can be gently rolling or almost flat. The exact height where trees stop growing changes depending on where you are in the world.

Climate

The alpine climate is the typical weather found in alpine tundra areas. As you go higher up a mountain, the air gets colder. This happens because the air expands and cools as it rises.

In alpine tundra, trees cannot grow because the weather is too cold and harsh. Summers are short, usually lasting between 45 to 90 days, with temperatures around 10 °C (50 °F). Even during summer, temperatures can drop below freezing, and frost can happen often. Most of the rain in these areas falls as snow during winter, but how much snow there is can change depending on the season, location, and landscape. Strong winds are common and can blow away soil and make it hard for plants to grow. The wind, together with strong sunlight, can also cause water to evaporate quickly.

Scientists have tried different ways to define what makes an alpine climate. One way looks at the warmest month’s temperature—if it’s below 10 °C (50 °F), trees usually cannot grow there. Another method considers both the warmest and coldest monthly temperatures. A more recent approach uses a special temperature measurement called "biotemperature," which helps better describe alpine climates.

Flora

Main article: Alpine plant

Plants in alpine tundra grow close to the ground because of strong winds, cold, snow, and ice. They are mostly grasses, sedges, and small flowering plants. These plants have strong roots that help them store food and stay alive during winter. It is rare to find plants that grow only one year.

Alpine plants have many ways to survive in harsh conditions. Some look like lumps of moss to stay safe from wind. Others have hairy stems or turn red to keep warm. Some plants take more than one year to bloom, protecting their flowers under the ground until summer.

Alpine areas change very quickly over short distances. A small rise or dip in the land can create very different conditions, from dry and windy to wet and snowy. Plants adapt to these changes, growing in patches that fit their needs.

In places where soil has formed, grasses and sedges create meadows. Lichens, which are a mix of fungi and algae, stick to rocks and soil. Though these plants seem tough, they can be easily damaged by walking, and it may take many years for them to grow back.

Fauna

Because alpine tundra is found in many different places around the world, no single animal lives in all of them. Some animals that live in alpine tundra areas include the kea, marmot, mountain goat, bighorn sheep, chinchilla, Himalayan tahr, yak, snow leopard, and pika.