What is warm humid climates

Last updated on May 15th, 2024 at 08:03 am

Warm humid climates are found in a belt near the equator extending to about 15 N and S. Examples of cities in this zone are: Logos, Dar-es-Salam, Mombasa, Colombo Singapore, Jakarta, Quito and Pernambuco.

There is very little seasonal variation throughout the year, the only punctuation being that of periods with more or less rain and the occurrence of gusty wind electric storms.

Air temperature, i.e. DBT, in the shade reaches a mean maximum during the day of between 27 and 32°C, but occasionally it may exceed the latter values.

At night the mean minimum varies between 21 and 27°C. Both the diurnal and annual ranges of temperature are quite narrow.

Humidity, i.e. RH, remains high, at about 75% for most of the time, but it may vary from 55 to almost 100% Vapour pressure is steady in the region of about 2500 to 3000 N/m².

Precipitation is high throughout the year, generally becoming more intense for several consecutive months.

Annual rainfall can vary from 2000 to 5000 mm and may exceed 500 mm in one month, the wettest month. During severe storms, rain may fall at an intensity of 100 mm/h for short periods.

Sky conditions are fairly cloudy throughout the year. Cloud cover varies between 60 and 90%.

Skies can be bright, a luminance of 7000 cd/m² or ever more when it is thinly overcast, or when the sun illuminates white cumulus clouds without itself being obscured.

When heavily overcast, the sky is dull, 850 cd/m² or less.

Solar radiation is partly reflected and party scattered by the cloud blanket or the high vapour content of the atmosphere, therefore the radiation reaching the ground is diffuse, but strong, and can cause painful sky glare.

Cloud and vapour content also prevents or reduces outgoing radiation from the earth and sea to the night sky, thus the accumulated heat is not readily dissipated.

Wind velocities are typically low, and calm periods are frequent, but strong winds can occur during rain squalls.

Gusts of 30m/s have been reported. There are usually one or two dominant directions.

Vegetation grows quickly due to frequent rains and high temperatures and it is difficult to control.

The red or brown laterite soils are generally poor for agriculture.

Plant-supporting organic substances and mineral salts are dissolved and washed away by rainwater.

The subsoil water table is usually high and the ground may be waterlogged.

Little light is reflected from the ground. Special characteristics: high humidity accelerates mould and algal growth, rusting and rotting.

Organic building materials tend to decay rapidly. Mosquitoes and other insects abound.

The thunderstorms are accompanied by frequent air-to-air electrical discharges.

In which areas hot-dry desert climate occurs? Also, explain the other characteristics of hot dry desert climate.

These climates occur in two belts at latitudes between approximately 15 and 30° north and south of the Equator. Examples of settlements in this zone are Assuan, and Baghdad. Alice Springs, and Phoenix.

Two marked seasons occur a hot and a somewhat cooler period.

Air temperature, i.e. DBT, in the shade rises quickly after sunrise to a daytime mean maximum of 43 to 49°C. The ever-recorded maximum temperature of 58°C was measured in Libya in 1922.

During the cool season, the mean maximum temperature ranges from 27 to 32°C.

Night-time means minima are between 24 and 30°C in the hot season and between 10 and 18°C in the cool season. The diurnal range is very great: 17 to 22 deg C.

Humidity, i.e. the RH, varies from 10 to 55% wet-bulb depression is large(rapid evaporation).

The vapour pressure is normally between 750 and 1500 N/m² precipitation is slight and variable throughout the year, from 50 to 155 mm per annum.

Flash-storms may occur over limited areas with as much as 50 mm of rain in a few hours, but some regions may not have any rain for several years.

Sky conditions are normally clear. Clouds are few due to the low humidity of the air.

The sky is usually dark blue, with a luminance of 1700 to 2500 cd/m², and further darkened during dust or sandstorms to 850 cd/m² or even less.

Towards the end of the hot period, dust suspended in the air may create a white haze with a luminance of 3500 to 10000 cd/m², which produces a diffuse light and a painful glare.

Solar radiation is direct and strong during the day, but the absence of clouds permits easy release of the heat stored during the daytime in the form of a long dust haze periods.

Winds are usually local. The heating of air over the hot ground causes a temperature inversion, and as the lower warm air mass breaks through the higher cooler air, local whirlwinds are often created.

Winds are hot, carrying dust and sand- and often develop into dust storms.

Vegetation is sparse and difficult to maintain because of the lack of rain and low humidity. The soil is usually dusty and very dry.

Strong sunlight illuminating a highly reflective light coloured and dry ground can create a luminance of 20000 to 25000 cd/m².

Soils dry quickly after rain and would generally be fertile if irrigated.

The subsoil water- table is very low. Special characteristics: during certain months dust and sand storms may be frequent.

The high daytime temperatures and rapid cooling at night may cause materials to crack and break up.

Explain monson climate in detail along with the region of occurrence & characteristic. 

This climate usually occurs in large land masses near the tropics of cancer and Capricorn, which are sufficiently far from the equator to experience marked seasonal changes in solar radiation and wind direction.

Examples of cities with composite climates: Lahore, Mandalay, Asuncion, Kano and New Delhi. The latter is shown as an example in

Humid Climates {Af (Wet Climate) Am (Monsoon) Aw (Wet and Dry)}

                                                

Two seasons occur normally. Approximately two-thirds of the year is hot-dry and the one-third is warm humid. Localities further north and south often have a third season, best described as cool- dry.

Humidity, i.e. the RH, is low throughout the dry periods at 20 to 55% with a vapour pressure of 1300 to 1600 n/m².

During the wet period, it rises to 55 to 95%, with a vapour pressure of 2000 to 25000N/m².

Precipitation: the monsoon rains are intense and prolonged; occasionally 25 to 38 mm can fall in an hour.

Annual rainfall varies from 500 to 1300 mm with 200 to 250 mm in the wettest month. There is little or no rain during the dry season.

Sky conditions markedly vary with the season. The sky is heavily overcast and dull during the monsoons, and clear, with a dark blue colour, in the dry seasons.

Towards the end of the hot-dry season, the sky becomes brighter with frequent dust haze. The intensity of sky glare varies accordingly.

Solar radiation alternates between conditions found in the warm-humid and the hot dry desert climates. Winds are hot and dusty during the dry period.

Directional changes in the prevailing winds at the beginning of the warm-humid season bring rain clouds and humid air from the sea. Monsoon winds are fairly strong and steady.