Saturday, July 18, 2009

DISTRIBUTION

The equatorial, hot, wet climate is found between 5 o north and 10 o south of the equator. Its greatest extent is found in the lowlands of the Amazon, the Congo, Malaysia and the East Indies. Further away from the equator, the influence of the on-shore trade winds gives rise to a modified type of equatorial climate with monsoonal influences. Within the tropics, the equatorial highlands have a distinctly cooler climate, modified by altitude, examples – Jos in Nigeria, Cameroun Highlands in Malaysia, etc.

CLIMATE

Temperature: the most significant feature of the equatorial climate is its great uniformity of temperature round the year. The mean monthly temperatures are around 27oC (80 oF) with very little variation. There is no winter, cloudiness and heavy rainfall help to moderate the daily temperature, so that even the equator itself cannot be unbearable. Also regular land and sea breezes help in keeping a truly equable climate. The temperature range within the equatorial region are around 2° C (4° F) or less for example Warri (Nigeria) has its hottest Month around 28° C (82° F) and its collest month around 26° C (78° F), therefore having its annual range around 2° C (4° F)

Precipitation: precipitation in the equatorial region is heavy, between 60 inches and 106 inches and is well distributed throughout the year. There is no month without rain and there are two periods of maximum rainfall, July and September, which occur shortly after the equinoxes. Least rain falls at the January and December solstices. But this simple pattern may be altered or changed by local conditions.

Below is a chart showing the annual precipitation of Ukpo town (Nigeria).


Due to the great heat in the equatorial belt, mornings are bright and sunny and there is much evaporation and conventional air currents are set up, followed by heavy downpours of Convectional rain in the afternoons from the towering Cumulonbus cloud. Thunders and lightening often accompany the torrential showers. The amount of rainfall recorded in one afternoon may be as much as the deserts receive for the entire year.

NATURAL VEGETATION

Equatorial regions support a luxuriant type of dense vegetation (the tropical rain forest) because of the very heavy rainfall (over 80 inches) and uniformly high temperature (27 ºC / 80 ºF). In the Amazon lowlands, the forest is so dense and so complete in its vegetation extravagance. The growing season in equatorial region is not restricted by either drought or cold, planting is down throughout the year.