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The Intertropical Convergence Zone is commonly known as the ITCZ. It is also called Equatorial
Convergence Zone (ECZ) or Intertropical Front. The Intertropical Convergence Zone refers to a belt
that is characterized by a belt of low pressure where the trade winds of the Northern and Southern
Hemispheres come together encircling the earth, generally near the equator. The belt is mostly
characterized by vigorous thunderstorms over broad areas due to convective activity. The position of
the ITCZ varies with different seasons. Thermal energy characterizes the weather in this region from
within the earth’s core and from the sun. This zone receives the highest amount of heat from the
sun. This phenomenon happens around June 20th when the sun is overhead the Tropic of Cancer at
23½ degrees North and around December 20th when the sun is overhead the Tropic of Capricorn at
23½ degrees south

Characteristics of The Intertropical Convergence Zone

Low air pressure mostly characterizes the ITCZ. The northern and the southern trade winds converge
at the ITCZ and to due to Earth’s rotation, the winds lose energy as they cross the equator. The heat
from the ocean currents makes the air warm at the Earth’s surface creating a region of low pressure.
Another characteristic of the ITCZ is humidity. Since the air in this belt keeps rising frequently, it
condenses in the atmosphere to form clouds. The belt receives afternoon showers due to high
humidity. Sailors refer to the Intertropical Convergence Zone as doldrums because the belt lacks
horizontal air movement since the warm air simply rises.

The ITCZ is not static, in that inconsistent location around the equator characterizes it. Different
places receive varying heat energy amounts as the earth rotates with the seasons. This movement
can result into a complete reversal of regular trade winds, especially in the Indian Ocean. The last
characteristic of the ITCZ is that it experiences storms. The rainfall received in this area is not gentle
rainfall and is characterized by thunderstorms.

El Niño and La Niña are opposite phases of what is known as the El Niño-Southern
Oscillation(ENSO) cycle. The ENSO cycle is a scientific term that describes the fluctuations in
temperature between the ocean and atmosphere in the east-central Equatorial Pacific
(approximately between the International Date Line and 120 degrees West).

La Niña is sometimes referred to as the cold phase of ENSO and El Niño as the warm phase of
ENSO. These deviations from normal surface temperatures can have large-scale impacts not only on
ocean processes, but also on global weather and climate.