Effects of climate due to Coriolis Effect

Global Atmospheric Circulation and Climate

Global atmospheric circulation is the way warm air is distributed throughout the Earth. The climate at a specific area of the Earth is directly related to the atmospheric circulation. Due to the nature of a sphere, different parts of the Earth receive different intensities of energy from the sun. At the equator the most energy is received from the sun since it is at a closer distance to the sun. The amount of energy at the tropics is more than it can emit, and on contrary, the poles emit more energy than they receive, this imbalance drives the circulation of atmosphere. In order for the heat to get transferred, the warm air rises from the tropics and then travels towards the poles and then sink down towards the ground. This single-celled circulation theory was proposed by Hadley. However, due to Earth’s rotation on a tilted axis, there are three cells: Hadley Cell, Ferrel Cell, and Polar Cell.

Hadley Cell

The Hadley Cell is located at the equator, it is also known as the tropical cell. At the equator, where the air pressure is low, warm, moist air is lifted up and carried towards the poles. Once the air reached 30° North/South of the equator, the air descends at a high pressure area (Schlanger). The warm air that descends has a huge impact on the environment at those locations. The winds that are created in this cell are called the Northeast trade winds, in the northern atmosphere and Southeast trade winds in the southern atmosphere (Molles). The warm air creates a warm environment at those regions with climate such as arid and semiarid, this is also where the largest deserts of the world are located, including the Sahara Desert. By the time the warm has arrived at the 30° location, the air is completely out of moisture, which explains why the areas at which the air descends at are such dry areas, refer to figure 3. The most common biomes at this latitude are tropical rainforest, tropical dry forest, and tropical savanna (Kalman). All three of these biomes are the warmest of all biomes, as well as the wettest of all biomes as well. When the energy from the sun reaches Earth and the warm air is released from the air as it rises, this is where the majority of the precipitation ends up which would explain why there is so much rain in these regions.

Ferrel Cell

The Ferrel Cell slightly overlaps the Hadley Cell and the Polar Cell in the mid-latitudes and brings air together from both of its neighboring cells, which is why it is also known as the Mid-latitude Cell. In the Ferrel Cell, air flows the opposite direction of the Hadley Cell. Air flows towards the poles at the surface and then flow towards the equator at higher altitudes, refer to figure two and look at the cells that are next to the Hadley Cells. This cell covers the areas that are 35° to 60° North/South of the equator. In the mid-latitude regions, there is great difference in temperature between different seasons. This is also a common area for violent storms and hurricanes to occur due to the great difference in temperature between the air coming from the tropic and air from the poles. At the 30◦ latitude mark is where the deserts are located. This is due to the fact that all the moisture in the air traveling towards the poles has been released and now there is only dry hot air left, which descends towards the surface. The desert has the least precipitation levels in the entire world, hot and cold periods can be experienced within 24 hours, there are no plants or water bodies to moderate the temperature (Kalman). As you move further towards the poles away from the desert the other types of biomes that exist within the Ferrel Cell area are temperate woodland, or chaparral, temperate grassland, and temperate forest. The temperate forests have wet winters and dry summers. Due to the hot summers, intense wildfires can occur, plants have evolved to use these wildfires for nutrient cycling (Kalman). The temperate grasslands is where the soil is most fertile, this region has wet summers and dry winters. In the temperate forest, temperatures do not vary extremely, there is lots of rainfall and the soils are fertile.

Polar Cell

At the 60◦ and above point is where the Polar Cell lies. The Polar cell is similar to the Hadley cell. Both of the cells carry warm air towards the poles. The climate at that latitude is considered to be artic and sub-artic, refer to figure 3. The biome present at this cell is tundra and boreal forest (Kalman). In this region winters are long and permafrost is common and temperatures rarely reach above 0◦C. Organisms that inhabit these environments are very much adapted to the cold. This extremely cold climate is due to the fact that very little sunlight reaches to the poles, as well as the fact that the air being circulated in this cell came from the equator and most of the heat in the air has been released earlier on.