Climate

What is climate?

Climate is the average weather usually taken over a 30-year time period for a particular region and time period. Climate is not the same as weather, but rather, it is the average pattern of weather for a particular region. Weather describes the short-term state of the atmosphere.

What is our climate system?

Our climate system is made up of the atmosphere, oceans, land, ice and our biosphere.

Atmosphere

The atmosphere covers the Earth. It is a thin layer of mixed gases which make up the air we breathe. This thin layer also helps the Earth from becoming too hot or too cold.

Oceans

Oceans cover about 70 percent of Earth’s surface. Their large size and thermal properties allow them to store a lot of heat.

Land

Land covers 27 percent of Earth’s surface and land topography influences weather patterns.

Ice

Ice is the world’s largest supply of freshwater. It covers the remaining 3 percent of Earth’s surface including most of Antarctica and Greenland. Ice plays an important role in regulating climate, because it is highly reflective.

Biosphere

The biosphere is the part of Earth’s atmosphere, land, and oceans that supports any living plant, animal, or organism. It is the place where plants and animals, including humans, live.

What is weather?

The weather is just the state of the atmosphere at any time, including things such as temperature, precipitation, air pressure and cloud cover. Daily changes in the weather are due to winds and storms. Seasonal changes are due to the Earth revolving around the sun.

What causes weather?

Because the Earth is round and not flat, the Sun’s rays don’t fall evenly on the land and oceans. The Sun shines more directly near the equator bringing these areas more warmth. However, the polar regions are at such an angle to the Sun that they get little or no sunlight during the winter, causing colder temperatures. These differences in temperature create a restless movement of air and water in great swirling currents to distribute heat energy from the Sun across the planet. When air in one region is warmer than the surrounding air, it becomes less dense and begins to rise, drawing more air in underneath. Elsewhere, cooler denser air sinks, pushing air outward to flow along the surface and complete the cycle.

Why do mountains affect weather and climate?

There are two sides to a mountain: wayward and leeward. Whenever it is raining, the wayward side gets the rain. As a cloud goes up the mountain, it keeps raining until there is no more water in the cloud. Now, as the cloud starts to go down the other side of the mountain, there is no more precipitation. So, the leeward side of the mountain doesn’t get any rain. The flat ground on this side of the mountain is dry and humid.

What is the Water Cycle?

Earth has a limited amount of water. So, that water keeps going around. We call it the water cycle. The water cycle begins with evaporation. Evaporation is when the sun heats up water in rivers, lakes or the ocean. Then turns it into water vapor or steam. The water vapor or steam leaves the body of water and goes into the air. Transpiration is the process by which plants lose water out of their leaves. Condensation is when water vapor in the air gets cold and changes back into water to form clouds. Think of it this way, when you open a cold soda on a hot summer day, your soda will start to sweat as water droplets form on the outside of the can. Precipitation occurs when so much water has condensed that the air can’t hold it anymore. This is how we get rain or snow. Collection happens when the precipitation falls and is collected back in the oceans, lakes and rivers. When it falls to the ground, it will soak into the earth and become ground water. This is the water cycle and it just keeps repeating.

Click Here to learn more about the Earth’s water cycle.

Why do the leaves change color?

During the spring and summer the leaves have served as factories where most of the foods necessary for the tree’s growth are manufactured. This food-making process takes place in the leaf in numerous cells containing chlorophyll, which gives the leaf its green color. Along with the green pigment are yellow to orange to red pigments as well. Most of the year these colors are masked by great amounts of green coloring. But in the fall, because of changes in the length of daylight and changes in temperature, the leaves stop their food-making process. The chlorophyll breaks down, the green color disappears, and the yellow to orange to red colors become visible and give the leaves part of their fall splendor. The best time to enjoy the autumn color would be on a clear, dry, and cool day.

What is deforestation?

Deforestation is the cutting down large numbers of trees to use the land for something instead of a forest. Cutting down trees can affect the climate. After rain falls on a forest, mist rises and new rain clouds form. When forests are cut down, this cycle is disrupted, and the area eventually grows drier, causing a change in the local climate. If huge areas of trees are cut down, the carbon dioxide they would have used builds up in the atmosphere and contributes to the greenhouse effect. And without trees to hold the soil and absorb water, rain washes topsoil away, a process called soil erosion.

What is erosion?

Erosion is the wearing away of the land by water, ice or wind. Soil erosion is a natural process. It becomes a problem when human activity causes it to occur much faster than under natural conditions. Wind and water are the main agents of soil erosion.

What is acid rain?

Acid rain is rain, snow or fog that is polluted by acid in the atmosphere and damages the environment. Two common air pollutants acidify rain: sulphur dioxide and nitrogen oxide. When these substances are released into the atmosphere, they can be carried over long distances by prevailing winds before returning to earth as acidic rain, snow, fog or dust. When the environment cannot neutralize the acid being deposited, damage occurs.