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The Lake Effect

Learn all about the lake effect and understand how a difference in temperature between the water of a lake and the surrounding air can give rise to weather phenomena.
May 22, 2023
3-5 minutes

Definition

By definition, the lake effect is a meteorological phenomenon that occurs when the air temperature over a lake is different from that of the surrounding air. This phenomenon is due to the difference in specific heat between water and air, which causes the water to warm or cool more slowly than the air. This effect can be observed throughout the year, but it is particularly pronounced during the transition seasons, such as spring and fall.

It is a phenomenon that is therefore related to the temperature of water and air having different specific heat properties.

Situations related to this phenomenon

The two situations related to this phenomenon:

During the summer, for example, the lake water may be cooler than the surrounding air. Thus, the air above the lake will also be cooler than the surrounding air, creating a breeze that blows from the water to the land. This breeze is called the lake breeze.

In winter, the phenomenon is reversed. The lake can be warmer than the surrounding air because the water takes longer to cool than the air. As a result, the air above the lake will be warmer than the surrounding air, creating a breeze that blows from the land to the water. This breeze is called the land breeze.

Impact of these breezes

On the climate

These breezes can have an impact on the local and regional climate. During the summer, lake breezes can cool the ambient air, creating a more pleasant climate for people and animals.  In the winter, the land breeze can warm the ambient air and reduce frost formation, which can be beneficial to crops and infrastructure.

Weather related

The breezes generated by the lake effect can have an impact on various weather phenomena such as thunderstorms, tornadoes, cloud formation and precipitation. Due to the temperature contrasts created by these breezes between warm and cold air, convergence zones can form, thus favouring the development of thunderstorms and tornadoes. These contrasts can also cause intense precipitation in some areas.

Focus on lake effect snow

Lake-effect snow, known as lake snow, is a meteorological phenomenon that occurs in winter when the temperature of the water in a lake is higher than that of the surrounding air. This temperature difference causes the lake water to evaporate, turn into vapor and rise into the colder air. In the clouds above the lake, this vapor condenses into ice crystals which, as they stick together, form snowflakes that fall on the areas surrounding the lake. Because of the special conditions that cause lake snow to form, it is often lighter and more powdery than ordinary snow.

On air and water quality

In addition, the lake effect can have an impact on air and water quality. In the summer, the breeze that forms can help improve air quality by bringing fresh, clean air to the land. However, in the winter, the breeze can blow pollution from the land into the lake, which can lead to decreased water quality.

On human activities

Ultimately, the lake effect can also influence human activities, such as fishing and boating. Lake breezes can make navigation easier, while land breezes can make it more difficult. In addition, water quality can impact fishing, as contaminated water can alter the quality and quantity of fish.