Have you ever visited a place that has different weather from where you live? Maybe you have seen pictures of a place like this, too. These places are likely a different biome than your home. A biome
is a large area of Earth with its own conditions and living things. The weather that usually happens here plays a big part in what life is like for the living things in each biome. Let's first talk about what makes the climate and weather in a biome, and then we will look at how these things work in the desert.Climate and the Ocean
is long term patterns of weather in a certain place. Climate is different from weather, because weather is day to day, and climate is how we think about the temperature and weather of a place overall. Let me show you what I mean: the climate in Florida is hot, which means most of the time, it is hot there. That doesn't mean that one day the weather can't be cold. A cold wind could be the weather for one day, maybe two, while the heat happens most of the time, which makes it part of the climate.
This map shows the different biomes across the world. Note that areas of relatively similar latitude have similar climates.
SEDACMaps at Flickr.com
Think of the difference between climate and weather like this: you live in New York, which means your summer is from June until September. So, if you want to plan a picnic, you would want to go in June because most likely, it will be warm out. That is because the climate during the summer is hot. But this doesn't mean it can't rain the day of the picnic. The rain is the weather for the day- it's not usual, but it could happen for a day or two.
Believe it or not, the ocean has a lot to do with climate. As sunlight makes the ocean warmer, the water evaporates, or turns into a gas, and moves up into the air. Water vapor is a greenhouse gas, which can make the air heat up. The ocean also helps cool a place down. The wind blows across the top of the ocean and sprays water into the air. Later, when the air gets cool or when the air can't hold any more water, the water changes states again and turns into clouds. Clouds will rain when they get too heavy, which also cools a place down.
The ocean plays a major role in the climate of an area. Places that are closer to oceans tend to have cooler climates overall.
Joanna Lee Osborn at Flickr.com
Let's see climate and weather in action in the desert biome. A desert
is a hot, dry area with a few plants and animals that have special features that help them live there. Deserts are often close to mountains. This means that the rain will hit the high mountains and not the lower deserts. All deserts are dry, but for different reasons. Some deserts are dry because of all the dry air around them. Other ones, like subtropical deserts, are very dry because they get a lot of heat from the sun, so water turns into a gas before it rains.
The Mojave Desert is on the lee side of mountains, which create a rain shadow after prevailing winds drop their water content on the mountains, causing the desert to remain dry.
keith schurr at Flickr.com
What makes the desert so hot and dry? Remember that the ocean has a lot to do with climate. Deserts tend to be far away from the ocean, so the cooling we talked about earlier can't happen in an easy way. This means there is less water in the air for clouds. If there are less clouds, the land will get more sunlight. The sun is also high in the sky over the desert, which means the sun shines straight down onto the land. Deserts have low humidity
, which is how much water vapor is in the air. Because of this, the heat from the sun goes away when the sun does. This means the desert gets very hot during the day and very cold at night.
The Sahara Desert in northern Africa is extremely dry because of the high-pressure, dry air descending on the area.
Véronique Mergaux at Flickr.com
Deserts are different than other biomes. Do you live in a desert climate? Maybe you have just visited one and felt the heat during the day and the cold at night for yourself. Think about the climate where you live. What is it like? Is it the same or different than the desert biome? If you also live far away from an ocean, it might not be so different!