In each hemisphere there are three atmospheric convections: the Hadley cell (fro

Question

In each hemisphere there are three atmospheric convections: the Hadley cell (from 0 degree -30 degree), the Ferrell cell (from 30 degree - 60 degree), and the Polar cell (from 60 degree - 90 degree). At 30 degree, the warm, extremely dry air mass descends from the tropopause earthward generating high air pressure. As this pressurized air mass reaches the surface of the earth, it travels both toward the equator (closing the Hadley cell convection) and poleward (beginning the Ferrell cell convection). As the air mass moves toward the poles from 30 degree, it begins to warm due to the higher temperatures at lower latitudes. As the air mass warms, it absorbs water vapor due the increased water holding capacity of the warmer air. As the air mass reaches the 60 degree parallel, the density of the air mass decreases causing the air to rise (akin to the process at 0 degree), creating an area of low air pressure. As the air rises, temperatures decline dropping the water holding capacity of the air mass, forming precipitation. This is the cause of the world's very cold, wet taiga forests (i.e. Southern Canada, Northern Europe, and Russia and Northern China) where coniferous trees dominate. As the air reaches the tropopause, it either moves back toward the equator or toward the poles. As the air mass moves away from 60 degree the air mass continues to cool releasing precipitation. This phenomenon provides rain and snow creating the cool, wet temperate forests of Northern United States, Southern Europe, and China. These forests typically are dominated by deciduous trees Similar to the Hadley cell though, once the water has completely precipitated, the air mass becomes dry. As the Ferrell cells travel towards 30 degree just below the tropopause, the temperatures continue to decline increasing the density of the air mass, causing the air mass to descend back to Earth at 30 degree, completing the Ferrell cell. The Polar cell (60 degree - 90 degree) convection shares many similarities with the Hadley cell. Though dry and cool relative to the equator, the air mass at 60" has enough thermal energy to rise driving the Polar and Ferrell cells. Once the air mass reaches the tropopause at 60 degree, it moves both poleward and towards the equator. In the Polar cell, the air mass moves towards the poles cooling and releasing precipitation as snow or rain. As the convection reaches the poles it descends as a cold, dry high-pressure air mass. Very little precipitation falls at extreme latitudes due to this phenomenon. Areas of the poles that are not dominated by glaciers. In extreme northern and southern latitudes have minimal moisture availability and an extremely short growing season, and are inhabited by very short scrubby vegetation in a biome known as the tundra.

Explanation / Answer

Ans Fig no. 3

a. Polar cell

b. Ferrell cell

c. Hadley cell

d. Hadley cell

e. Ferrell cell

f. Polar cell

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.