Lesson 6 — Activity 3: How Oceans Moderate Climate
Completion requirements
Lesson 6 — Activity 3: How Oceans Moderate Climate
Explore
Does being near a large body of water, such as an ocean or large lake, have a moderating affect on climate? You will investigate this question in the following activity.
Climate is a trend in the weather over an extended period of time. Let's see how large bodies of water have a moderating influence on climate. (Moderating means not excessive or extreme.)
Oceans are able to store large amounts of heat (thermal energy). This prevents the area around them from having very extreme temperature changes. Oceans moderate the climate of land areas near them. This means that they prevent the land areas near them from becoming either too hot or too cold. This is how it works:
In cool weather, an ocean releases a great amount of heat without cooling much itself. Even during very hot or very cold days, and as the seasons change, the temperature of oceans remains constant (the same).
As the sun warms the air above the ocean, heat flows from the air into the water, cooling the air. When the temperature of the air above the ocean cools, heat flows from ocean to air and warms the air. Oceans prevent land near them from getting very warm or very cold. Because of this, coastal cities like Vancouver, shown in the image below, have moderate climates.
Compare this to a city like Calgary. How will its location affect its climate?
Calgary is inland and near mountains. Winds from the mountains affect its climate. At night, air near the mountains cools, sinks, and flows toward the valleys in Calgary. These mountain winds cool the city. Calgary also has a prairie-steppe-type climate. This means it usually enjoys sunny weather, even in winter, and most of its rainfall comes in summer.
What does living next to a body of water have to do with air temperature?
In areas like Vancouver where there is a lot of water, temperature changes are more gradual because water absorbs thermal energy at a slower rate than land does. For instance, sand absorbs or releases heat six times faster than water.
During the day, the water slowly absorbs heat while the ground quickly absorbs heat. Similarly, during the night, the water slowly releases the heat but the ground quickly loses the heat. Heat travels from an area of high temperature to low temperature. As a result, during the day, warmer air moves from the land to the water and, therefore, cools the land. At night, a warm breeze travels from the water to the land because the air temperature above the water is higher than that above the land.
In areas where there is not much water, temperature changes from day to night are more noticeable because the land absorbs and releases thermal energy quickly. You have probably heard stories about the extreme temperatures in the deserts — freezing at night and very hot in the day. Now, you know why that is so!
What does living next to a body of water have to do with air temperature?
In areas like Vancouver where there is a lot of water, temperature changes are more gradual because water absorbs thermal energy at a slower rate than land does. For instance, sand absorbs or releases heat six times faster than water.
During the day, the water slowly absorbs heat while the ground quickly absorbs heat. Similarly, during the night, the water slowly releases the heat but the ground quickly loses the heat. Heat travels from an area of high temperature to low temperature. As a result, during the day, warmer air moves from the land to the water and, therefore, cools the land. At night, a warm breeze travels from the water to the land because the air temperature above the water is higher than that above the land.
In areas where there is not much water, temperature changes from day to night are more noticeable because the land absorbs and releases thermal energy quickly. You have probably heard stories about the extreme temperatures in the deserts — freezing at night and very hot in the day. Now, you know why that is so!
Self-Check
Try This!