Climate is the long-term accumulation of the atmospheric components (and their changes) that, in the short term, consist of weather at a specified place.

World climates are classified as hot-wet equatorial climates, savanna climates, tropical monsoon climates, desert climates, steppe climates, Mediterranean climates, Warm Temperate Eastern Margin Climates, British type climates, taiga climates, Laurentian climates, and polar climates.

1. World Climate: Hot, Wet Equatorial

DISTRIBUTION

• 50N – 100S from the equator
• The absence of trade winds will result in a monsoon-like climate if you move away from this.
• Basically, a hot, damp environment, however, there are some cool places, such as Cameron Highlands in Malaysia, due to their high altitude.
• Examples are Ecuador, Colombia, Brazil, Peru, Nigeria, Liberia, Myanmar, Thailand, Cambodia, Malaysia, Java

CLIMATE

• There is great uniformity of temperature throughout the year.
• The average monthly temperature is consistently between 24 and 27ºC, with very little variance.
• There is no winter.
• The diurnal and annual range of temperature is small.
• Between 6 and 10 inches of heavy, evenly spaced-out precipitation fall each year.
• Its defining attribute is the two-fold rainfall peaks that occur around the equinoxes.

NATURAL VEGETATION

• Supports a luxuriant type of vegetation – the tropical rainforest.
• Amazon tropical rain forest is known as Selvas.
• Numerous evergreen trees that produce tropical hardwoods including mahogany, ebony, greenheart, and cabinet wood are found there. Also dyewoods.
• Lianas, epiphytic and parasitic plants are also found.
• In such vegetation, trees of a single species are rare.

2.Savanna or Sudan Climate (or Tropical Wet and Dry Climate)

• Between equatorial woods and trade wind-heated deserts, the savanna or Sudan climate can be found.
• It is restricted to the tropics (Tropics of Cancer and Capricorn) and is most developed in Sudan, where dry and wet climates are most distinct, therefore the name Sudan climate.
• It covers much of Africa (Keya, Nigeria, Gambia) as well as large areas of Australia, South America (Brazilian highlands), and India.
• The Savana Climate features a distinct dry season in the winter compared to other world climates. The region’s rainfall is concentrated throughout the summer. Much vegetation dies during the lengthy dry season, and waterways dry up, causing animals to migrate.

DISTRIBUTION

• It is located on either side of the equator in tropical latitudes. It is well developed in Sudan, where there are distinct rainy and dry seasons, hence the name.
• Africa (African Sudan, East Africa) and South America have this climate in the northern hemisphere (Llanos grasslands of Orinoco river basin).
• This climate is prevalent in Australia, South America (Campos grasslands of the Brazilian Highlands), and the southern hemisphere (in Northern Australia – south of its monsoon strip).

TEMPERATURE

• For lowlands, monthly temperatures in this area might vary from 20 to 32 degrees Celsius, but the range widens as one gets farther from the equator.
• The annual average temperature is around 18 degrees centigrade
• The greatest temperature is in April in the northern hemisphere and October in the southern hemisphere, right before the start of the rainy season. The summer solstice falls in the northern hemisphere in June, but it is not the hottest month.
• A cloudy sky causes temperatures to fall during the rainy season. Midday temperatures frequently exceed 37 degrees Celsius in the summer.
• Temperatures dip below 10 degrees centigrade even in the hot season due to rapid radiation loss at night caused by clear skies. A frequent occurrence during this season is night frost.
• Thus, a typical characteristic feature of the Savanna climate is the extreme diurnal range of temperature.

PRECIPITATION

• The region is characterized by a hot, rainy season and a cool, dry season.
• The hot and humid season lasts from May until September in the northern hemisphere (e.g., Kano, in Nigeria). The remainder of the year is chilly and dry. Over 80 centimetres of rain occur annually in Kano, which is more than 1500 metres above mean sea level, with the majority of it falling during the summer.
• In the southern hemisphere, the rainy season begins in October and ends in March.
• As one proceeds away from the equator and towards the desert borders, the length of the rainy season and total annual rainfall both decrease significantly.

WINDS

• The prevailing winds of the region that deliver rainfall to the coastal areas are known as trade winds. Easterly breezes blow from east to west, so rainfall is most on the east coasts.
• In the summer, when the ITCZ is located over a scorching desert, they are at their strongest. They move over the coastal regions, expelling all the moisture, and by the time they get to the interiors of the continent, they are comparatively dry.
• The easterly trade winds in West Africa blow offshore, bringing dry, dusty winds from the Sahara to the coast of Guinea. This hot, dry, dusty breeze is referred to locally as “the doctor” or “Harmattan.”
• Although Harmattan has a terrible impact on the crops, it also has a cooling effect. By speeding up evaporation, it offers some relief from Guinea’s humid air.
• Trade winds are to blame for the region’s distinct, alternating dry and wet seasons. Rainfall is brought on by onshore trade winds during the summer. Off-shore winds keep the weather dry during the winter.

VEGETATION

• Tall grass and little trees make up much of the local vegetation. ‘Parkland’ or ‘bush-veld’ are other terms for grassland.
• Along with the river banks, tree cover is maximum towards the equator and declines in density and height further from it.
• The trees are deciduous, which means they lose their leaves in the cool, dry months to reduce transpiration losses. Acacia is a classic representative of this kind.
• Other tree varieties include those with wide trunks that function as water reservoirs to assist them to endure dry spells or droughts. For instance, bottle trees, baobabs, etc.
• They are hardwood trees, sometimes thorny, which exude gum like the ‘gum Arabic.
• This region’s grass is unusually tall and coarse, reaching heights of 6-12 feet. Elephant grass, the highest type of grass, may reach heights of 15 feet.
• The grass is dense, with lengthy roots that stretch down for water. The grass appears dormant throughout the dry season and blooms during the rainy season.
• As one approaches the desert, the grasses give way to prickly shrubs.

WILDLIFE

• The savanna is home to some of the world’s largest terrestrial species.
• The two main groups of animals include – herbivores and carnivores.
• Zebra, giraffe, elephant, antelope, and other savanna herbivores are well-known. Herbivores are either blessed with exceptional speed to flee or have camouflage abilities to avoid carnivores.
• This region’s carnivores include lions, hyenas, leopards, panthers, pumas, and jaguars, among others. For attacking other animals, they have powerful jaws and teeth.
• Aside from rhinos and hippos, reptiles such as crocodiles, monitor lizards, and giant lizards can be found in rivers and marshy areas.

3. World Climate: Tropical Monsoon Climate

• The area between the Tropics of Cancer and Capricorn is home to the monsoon climate, commonly referred to as the tropical monsoon climate.
• The inter-tropical convergence zone (ITCZ), which moves through the area, influences its world climate, which is hot and muggy throughout the year.
• Monsoons are seasonal breezes that blow over land from the oceans and vice versa.
• They are distinguished by a seasonal reversal in wind direction, which causes temperature and precipitation changes.
• Summer, winter, and rainy seasons are the three prominent and distinct seasons of this climatic region.

DISTRIBUTION

• They are confined within 5 – 30 degrees latitudes on either side of the equator.
• Thailand, India, and Indo-China (Laos, Vietnam, and Cambodia). This world climate can be found in southern China and northern Australia.

WINDS

• Seasonal wind reversal is caused by the differential pace of heating and cooling of continental landmasses and seawaters.
• During the summer, as the sun passes overhead the Tropic of Cancer, a low-pressure zone forms over Central Asia. As a result, the Asian continent warms quicker than the surrounding oceans, which remain at a higher pressure in the northern hemisphere.
• In the southern hemisphere, winter conditions prevail, leading to a high-pressure zone over northern Australia.
• Winds blow out from the Australian landmass towards Java (Indonesia) and are drawn to the low-pressure region over the Indian subcontinent after crossing the equator due to the Coriolis force. These are the South-West monsoon winds.
• During winters, a reversal in the wind direction occurs.

TEMPERATURE

• Summers are warm to hot due to the region’s proximity to the tropics.
• The average monthly temperature is over 18 degrees Celsius, however, in the summer, the maximum temperature can reach 45 degrees Celsius.
• The average temperature in the summer is around 30 degrees centigrade, with an overall temperature range of 30 to 45 degrees centigrade.
• Winter temperatures range from 15 to 30 degrees Celsius. In the winter, the average temperature is around 25 degrees Celsius.

PRECIPITATION

• The region receives a lot of rain in a short period of time.
• The annual average rainfall is roughly 200-250 cm. However, some areas have a very high average of around 350 cm.
• Maysynram and Cherrapunji in the Khasi Hills (Meghalaya) receive over 1000cm of rain per year. They are positioned on the hills’ windward side, resulting in significant orographic rains (caused by a lift of the monsoon winds). These areas receive a lot of rain because of their placement between mountains, which generates a concentration of rain-bearing clouds, also known as the funnelling effect.

SEASONS

Unlike the tropical world climate, which has no distinct seasons, the monsoon climate has significant seasonal changes in meteorological conditions.

THE HOT DRY SEASON

• This lasts from March to mid – June.
• The sun is in a northward shift to the Tropic of Cancer. This causes the temperatures to rise sharply.
• In Central India, average daytime temperatures exceed 35 degrees Celsius. Temperatures in Sindh and south India can reach 44 degrees Celsius.
• Temperatures are lower at the seaside due to the influence of sea breezes.
• Except for the occasional thunderstorms, there is little rainfall during this season.

THE RAINY SEASON

• This lasts from mid – June to September
• The rains begin with a monsoon ‘burst’ over the subcontinent. It causes torrential rains over the country.
• During this season, the country receives more than 70% of its annual rainfall.
• This is a typical aspect of the monsoon type of climate, with concentrated heavy rainfall throughout the summer months.

THE COLD DRY SEASON

• This season begins in October and lasts until February.
• Also known as the receding monsoon season. The southwest monsoon begins to withdraw southwards when the sun begins its southward journey, eventually leaving the Indian landmass entirely.
• As the land mass’s temperatures start to drop, the Indian subcontinent experiences a higher pressure than the nearby seas. This makes the winds blow away from the continent and toward the sea.
• In the months of November and December, winds from the northeast start to blow over the Bay of Bengal, bringing some rain to India’s southeast coastline area.
• The Western Disturbances bring some rain and snow to the north, but overall the area is dry. Winter crops require frontal (cyclonic) rains brought on by the western disturbances in order to survive.

MONSOON FORESTS

• Also known as the Tropical Monsoon Forests.
• The majority of these are deciduous trees, which have a specific season for leaf loss. To reduce transpiration losses during the dry/drought season, they shed their leaves.
• They are classified as moist deciduous when the annual rainfall exceeds 150cm and dry deciduous when the annual rainfall is less than 150cm.
• Similar to equatorial rainforests, they consist of broad-leaf hardwood trees. However, the forests are less dense, more open, and have a smaller variety of species (flora as well as fauna).
• Evergreen rainforests of the tropical kind can be found anywhere there is a rainfall of more than 200–250 cm. These are prevalent in India’s Andaman and Nicobar islands, forests in the northeast, and the southern Western Ghats. Southeast Asian islands also include them.
• Savanna-like grasslands with sporadic trees are present anywhere there is little rainfall.
• As a result, monsoon vegetation ranges from thick forests to thorny scrublands (savanna).

4. World Climate: Desert Climate

• Desert regions are distinguished by little rainfall and sparse vegetation. The growing season is restricted to a brief rainy season.
• Due to a lack of moisture and food, the region’s landscape is devoid of plants and animals.
• They can be of two types:

hot deserts– like the Saharan desert

HOT DESERTS – DISTRIBUTION

• The world’s most important hot deserts are located on the western margins of continents between latitudes 15 to 30 degrees north and south.
• The Sahara desert, which has an extent of 3.5 million square miles, is the largest of the hot deserts. The Great Australian Desert, Arabian Desert, Kalahari Desert, Thar Desert, and others are notable examples of hot deserts.
• America also contains hot deserts. They are referred to in North America as the Mohave, Sonoran, Californian, and Mexican deserts. They run from the United States to Mexico. The Atacama or Peruvian deserts are found in South America.

HOT DESERTS – TEMPERATURE

• These deserts have some of the highest temperatures on earth and experience scorching weather all year round.
• They do not have a distinct cold weather season.
• Summertime averages are consistently above 30 degrees Celsius.
• Libya had the highest recorded temperature in 1922. The temperature increased to a maximum of 57 degrees Celsius.
• Such high temperatures are caused by clear skies, intense insolation, dry air, and a quick rate of evaporation.
• However, because of the regulating effect of the seas, the coastline regions of these deserts enjoy a comparatively temperate climate. The cooling influence of cold currents also lowers the region’s typical temperatures.
• The interior regions experience extreme temperatures – hot summers and cold winters.
• The temperature varies greatly throughout the day. The temperature rises with the sun during the day due to strong solar radiation, dry air, and clear skies.
• However, as soon as the sun sets, the mercury falls below the mean temperature because of the constant radiation-driven heat loss and the lack of cloud cover that would normally trap the heat.
• The average diurnal range of temperatures is around 14 to 25 degrees centigrade.
• During winter nights, frost is a common occurrence.

HOT DESERTS – PRECIPITATION

• The average annual precipitation in these regions is not more than 25 cm.
• These deserts are situated in the Sub-Tropical High-Pressure Belts, often referred to as the Horse Latitudes, where the air masses are descending, making it difficult for clouds that could produce precipitation to form.
• The Trade Winds, which blow offshore and prevent any moisture-laden winds from the sea from blowing over these regions, are the dominant winds in these areas.
• On-shore westerlies do not pass over desert areas, which lowers the likelihood of any precipitation.
• The relative humidity of the winds that travel over deserts is reduced since they originate in cooler climates. This lessens the likelihood of water vapour condensation and consequent precipitation.
• From 60% in the coastal regions to less than 30% in the interior, relative humidity falls. This makes these desert regions permanently dry by increasing the rate of evaporation and decreasing the likelihood of precipitation.
• Desiccating these deserts is the result of the cold currents that travel over the west coasts of the continents. Only drier winds blow over the deserts because any sea-borne winds carrying moisture condense into mist or fog over the cold currents.
• However, convectional rainfall occurs in these areas for shorter periods of time in the form of intense thunderstorms. Landslides are a common and disastrous result of these abrupt downpours.
• With less than 2 cm of annual precipitation, the Atacama Desert is the driest place on earth.

MID-LATITUDE DESERTS – DISTRIBUTION

• These deserts are frequently found on plateaus and are found in continental interiors.
• They include the Gobi desert, Turkestan desert, Patagonian desert, etc.
• In India, the Ladakh desert falls under this category.

MID-LATITUDE DESERTS – CLIMATE

• The world climate conditions of these deserts are comparable to those of hot deserts in many aspects.
• Because these deserts are located far from the shore or are surrounded by high mountains, they are shut off from the moisture-laden breezes blowing from the seas.
• Average annual precipitation does not exceed 25 cm.
• However, depressions may infrequently enter these Asian deserts, bringing wintertime little precipitation. Convectional precipitation is a possibility in the summer.
• These areas see a wider range of yearly temperatures than hot deserts. Continentality, a phenomenon linked to landmasses located far from the coast, is the cause of these severe temperatures.
• These areas have extremely cold winters with subfreezing temperatures. In rare cases, summertime ice thawing results in widespread flooding.

DESERT VEGETATION

• All deserts have some form of vegetation such as grass, scrub, weeds, etc.
• Although they may not always appear green, they are dormant and waiting for unpredictable rainfall.
• The xerophytic or drought-resistant scrub is the most prevalent plant type in both hot and mid-latitude deserts.
• Bulbous cactus, long-rooted wiry grasses, thorny bushes, and dwarf acacia are some significant species of this kind.
• Clusters of date palms can be found in a few places with plenty of groundwater, particularly in hot deserts.
• These areas support a unique species of vegetation that has evolved to withstand extreme aridity.
• Due to the lack of moisture, which decreases the pace at which organic matter decomposes, soils are lacking in humus.
• These desert shrubs have a sophisticated network of extended roots that expand in quest of moisture. To reduce water loss through transpiration, they have few or no leaves and foliage that is hairy, waxy, or needle-shaped.
• These plants’ seeds, which have thick, hard exterior surfaces, have unique defences to keep them safe while they’re dormant. They begin to sprout as soon as the rain moistens them.

LIFE IN THE DESERTS

• Despite their inhospitable conditions, different types of human settlements have come up in these deserts
• Primitive hunters and gatherers: These are tribes that do not domesticate any animals or grow any crops. They include the Bindibu, the Australian Aborigines, and the Bushmen of the Kalahari Desert.
• Nomadic herdsmen: They survive off of their herds and travel through the deserts in quest of water and lush pastures. They consist of the Mongols of the Gobi Desert, Tuaregs of the Sahara, and Arabian Bedouins.
• Settled cultivators: They have survived close to rivers such as the Nile in Egypt, Indus in Pakistan, Colorado in the USA, and Tigris-Euphrates in Iraq. They cultivate crops like wheat, barley, sugarcane, fruits, and vegetables
• Mining settlers: Prominent among these include the gold mines in Australia, Diamond mines in Kalahari, Copper mines in Chile, Silver mines in Mexico, and Oil in the Persian Gulf countries.

5. World Climate: Steppe Climate

• The term steppe refers to a region that is a semi-desert with grassland or shrub vegetation.
• Steppes are intermediate regions, not receive enough rainfall to support a forest but are also not as dry as a desert.
• The Steppe Climatic region is also known as Temperate Grasslands.
• These grasslands are some of the most developed agricultural fields and are termed grain baskets.
• Livestock ranching is another major activity carried out in these areas due to the availability of natural grasses.

DISTRIBUTION

• Steppes are found in the continental interiors.
• They are usually found in temperate latitudes and hence come under the influence of Westerly winds.
• Steppes are characterized by vast grasslands which are, by and large, devoid of trees.
• Steppes typically refer to the vast temperate grasslands of Eurasia, which stretch between the Black Sea coast on the east to the Altai mountains in the west, covering a length of over 2000 miles.
• Steppes are known by their regional names in different parts of the world. They include,
• Prairies – North America
• Pustaz – Hungary
• Pampas – Argentina and Uruguay
• Velds (High Veld) – South Africa
• Downs – Australia
• Canterbury – New Zealand

PRECIPITATION

• The average annual rainfall over the steppes varies from 25 to 75 cm, depending upon the region.
• The highest rainfall occurs in the spring season, or just prior to the onset of summer. In the northern hemisphere, it occurs in the months of June and July.
• During the winters, Westerlies bring in occasional depressions which often cause snowfall over these regions. However, the overall precipitation in the winter is low, at an average of 25 cm.
• In the southern hemisphere, due to a larger influence of maritime weather, higher rainfall occurs over these regions as compared to their counterparts in the northern hemisphere.

TEMPERATURE

• These regions are under the effect of continentality and hence experience extremities in temperature.
• Summers are warm with the average temperature in the range of 18-20 degrees centigrade.
• Winters are usually cold with occasional snowfall.
• The steppes in the northern hemisphere have a very high annual range of temperatures.
• In contrast, the steppes in the southern hemisphere, due to maritime influence, have a moderate climate throughout the year.

WINDS

• The prevailing winds of these regions are the Westerlies, which are responsible for precipitation during the winters.
• Apart from these, there are many local winds that blow over these regions and have a significant impact on the local weather.
• They are known by various names such as Mistral (France), which is cold dry wind; Loo (Gangetic plains), Sirocco (Sahara), Foehn (Alps), etc. are warm, dry winds.
• Over the North American Prairies, the Chinook is a hot, dry local wind. Flowing from the southwest, it is a katabatic wind that is descending from the Rocky Mountains.
• It is a scorching breeze, and in only 20 minutes it elevates the temperature in the area by more than 5 degrees centigrade.
• Because it melts the snow covering the pastures so the animals may graze there, it is helpful for local agriculture.

VEGETATION

• In contrast to tropical savanna grasslands, which are interspersed with trees, temperate grasslands are nearly treeless. Furthermore, the grass in these grasslands is substantially shorter than in the savanna.
• Unlike the coarse grass found in savannas, the grass here is fresh and healthy. This is primarily true for North American prairies, as well as the Chernozem grasses of Ukraine. The prairie soils are also rich in nutrients.
• The grass is lean, thin, and scattered.
• This makes them suitable for ranching, or large-scale cattle husbandry.
• The grass growing season lasts all year, despite seasonal fluctuations in temperature and precipitation.
• Conifers can be found in a transitional zone of woods near the poleward spread of prairies.
• Trees are placed around croplands in steppe farmlands to protect them from severe winds.

6. Mediterranean Climate (Western Margin Climate)

• The Mediterranean climate or warm temperate western margin climate is found between 30o and 45o North and South of the Equator.
• This climate is found in relatively few regions of the planet and is nearly entirely restricted to the western borders of continental landmasses.
• The basic cause of this climate is the seasonal shift of the wind belts.

DISTRIBUTION

• Central Chile,
• California (around San Francisco),
• The south-western tip of Africa (around Cape Town),
• Southern Australia (in southern Victoria and
• Around Adelaide bordering St, Vincent, and Spencer Gulfs), and south-west Australia.

CLIMATE

• The Mediterranean climate is distinguished by its dry, warm summers and rainy, chilly winters, as well as local winds.

DRY, WARM SUMMERS WITH OFF-SHORE TRADE WINDS

• During the summer, the sun is directly overhead the Tropics of Cancer and Capricorn.
• The Westerlies’ influence belt has drifted poleward, and rain-bearing tradewinds are expected to be off-shore.
• Thus, the areas basically experience no summertime rain, remaining dry.
• The heat is intense and the days are excessively warm.
• Durable droughts are frequent in the interior. There is typically little relative humidity.
• Summer temperatures are relatively high, with the highest recorded temperatures occurring away from the shore in the continental interiors of the Balkan peninsula, the Anatolian plateau, and the Mediterranean Middle East.

WET, COLD WINTERS WITH ON-SHORE WESTERLIES

• During the winter months, the Westerlies belt swings equatorward, bringing on-shore Westerlies to the Mediterranean.
• Hence, these lands receive almost all of their precipitation during the winter months.
• In September and October in Mediterranean Europe, the rain falls in torrential downpours and causes flooding.

LOCAL WINDS

Because of the topography of the region, which includes the Alps in the north, the Sahara desert in the south, continental interiors in the east, and the open Atlantic in the west, the Mediterranean climatic region in Europe experience several local winds. Temperature, pressure, and precipitation all vary greatly as a result. The two most important local winds are:

SIROCCO

• This is a hot, dry, and dusty wind.
• It originates in the Sahara desert and can happen at any time of the year, but it’s most common in the springtime.
• Normally it lasts only for a few days.
• It blows into the Mediterranean Sea from the interior Saharan desert and is typically connected to Atlantic Ocean depressions.
• Although it is significantly cooled after crossing the Sea due to the absorption of water vapour, the heat causes the local vegetation and crops to wither.
• Hence it is also called “Blood Rain” because it is carrying the red dust of the Sahara desert.

MISTRAL

• Mistral is a cold wind from the north.
• It rushes down the Rhone valley, accelerating due to the valley’s funnelling action between the Central Massif and the Alps [Plateau in France].
• In very severe situations, the wind’s velocity can be so strong that trains and trees can be uprooted.
• In winter, if the Mistral is frequent the temperatures could go below the freezing point.

OTHER LOCAL WINDS

• Bora: Cold north-easterly wind along the Adriatic coast.
• Tramontana and Gregale: cold winds in the Mediterranean Sea.

NATURAL VEGETATION

• The vegetation of the region is not luxuriant.
• Trees with small broad leaves are widely spaced.
• This climate’s distinctive lack of shade and the growth that occurs nearly exclusively in the fall and spring are other peculiarities.
• Heat, dry air, high evaporation, and protracted droughts are continuous targets of plants.
• Hence they are generally xerophytic or drought resistant in nature.

TYPES OF MEDITERRANEAN VEGETATION:

The vegetation consists of Evergreen forests, evergreen coniferous forests, grass, bushes and shrubs.

• They are open forests with evergreen oaks, only found in climatically favourable areas with annual precipitation of over 25 inches.
• The cork oaks are used for making wine-bottle corks.
• In Australia, the eucalyptus forests replace the evergreen oak.
• The giant sequoia or redwood is typical of Californian trees.

EVERGREEN CONIFEROUS FORESTS

• They include various kinds of pines, firs, cedars, and cypresses.
• Where there are fewer severe droughts and higher temperatures, they are more common.

BUSHES AND SHRUBS

• This is the most prominent type of Mediterranean vegetation.
• The low bushes grow in scattered clumps and are often thorny.

GRASS

• Because most of the rain falls during the cool season, when development is slow, the conditions in this region are unsuitable for grass.
• They are generally wiry and bunchy and are not suitable for animal farming.
• Thus cattle rearing is not an important occupation in the Mediterranean

7. Warm Temperate Eastern Margin Climate

• It is located near the eastern edges of the continents between 20 and 35 N and S latitude.
• The region has a monsoonal climate, with rain in the summer and dry weather in the winter.

VARIATIONS OF WARM TEMPERATE EASTERN MARGIN CLIMATE

1. China Type: Temperate monsoon or China type is found in most parts of China and is a modified form of monsoonal climate.
2. Gulf Type: Though less pronounced, the overall climate resembles the China Type. It is found in the southeastern parts of the USA bordering the Gulf of Mexico. The continental heating during summers induces an inflow of air from the cooler Atlantic Ocean.
3. Natal Type: In Southern Hemisphere, this climate is witnessed in New South Wales, Natal, and Parana-Paraguay-Uruguay basin. This is often referred to as the Natal Type of climate and is influenced by the on-shore Trade winds all around the year.

CLIMATE

• It is typified by a warm moist summer and a cool, dry winter.
• Occasionally, the penetration of cold air from the continental interiors may bring down the temperature to the freezing point.
• The relative humidity is a little high in mid-summer but most of the time, the climate is pleasantly warm.
• Rainfall is more than moderate and ranges between 60 cm to 150 cm and there is a uniform distribution of temperature throughout the year.
• Rain comes either from convectional sources or as orographic rain in summer, or from depressions in prolonged showers in winter.
• Local storms also occur. Examples: typhoons, and hurricanes.
• The rainfall is adequate for all agricultural purposes and hence the areas are densely populated.

CHINA TYPE

• It is the most typical of the warm temperate eastern margin climate.
• In summer due to intense heating of the continental interiors of the heart of Asia including Tibet, a low-pressure system is set in which attracts the tropical Pacific air stream.
• This is witnessed as the South-East monsoon in the region.
• In winter, there is intense high pressure over Siberia and the continental polar air stream flows outwards as the North-West Monsoon, bitterly cold and very dry.
• There is little rain but there is considerable snow.
• The region also experiences intense tropical cyclones called typhoons that originate in the Pacific Ocean and are most frequent in the late summer.

THE GULF TYPE

• The Gulf-Atlantic regions of the USA experience this type of climate similar to the China type but with less monsoonal characteristics.
• The warm Gulf Stream and the on-shore Trade winds help bring down the range of temperatures and there is a heavy annual rainfall of around 59 inches.
• The amount of rain is increased by thunderstorms in summer and by hurricanes in September and October.
• Due to intense local heating, the region also experiences violent tornadoes leading to heavy destruction.

NATAL TYPE

• The narrowness of the continents and the dominance of maritime influence eliminate the monsoonal elements.
• The South-East Trade winds bring about a more even distribution of rainfall throughout the year.
• The annual range of temperature is low and rain comes in prolonged showers.

NATURAL VEGETATION

• Due to heavier rainfall, the region supports luxurious vegetation.
• There is perennial plant growth and the conditions are well-suited to a rich variety of plant life.
• The lowlands carry both evergreen broad-leaved forests and deciduous trees, similar to the tropical monsoon forests.
• In the highlands, are various species of conifers such as pines and cypresses which are important softwoods.
• Eastern Australia – Eucalyptus
• South-Eastern Brazil, eastern Paraguay, north-eastern Argentina – Parana pine, the quebracho, wild yerba mate trees.
• Natal: palm trees

8. World Climate: British Type Climate

• British-type climatic regions are under the permanent influence of the Westerlies all around the year.
• These are also regions of high cyclonic activity., typical of Britain and thus said to experience the British climate.
• This climate is also referred to as the cool temperate western margin climate or the North-west European Maritime Climate.

DISTRIBUTION

There are exists of the northern hemisphere and southern hemisphere distributions.

NORTHERN HEMISPHERE

• The climatic belt stretches from Britain into North-West Europe, including northern and western France, Belgium, the Netherlands, Denmark, western Norway, and also north-western Iberia.
• It primarily affects the coastlands of British Columbia in North America. The North American Rockies prohibit on-shore Westerlies from penetrating far inland.

SOUTHERN HEMISPHERE

• The majority of New Zealand, especially the South Island, Tasmania, southern Chile, and southern Australia all enjoy this climate.
• The surrounding wide stretches of water have made these areas’ climates more marine.

CLIMATE

• Mild winters and moderately warm summers. Temperature extremes are unlikely.
• Adequate rainfall throughout the year.

TEMPERATURE

• The mean annual temperature is usually in the range of 5 C – 15 C.
• This range is comparatively small for such high latitudes.
• Winters are unusually mild with no station recording temperatures below freezing, while summers are seldom particularly warm.
• The North Atlantic Drift’s warming influence and the South-Westerlies’ predominance are to blame for this.
• Hence, they are some of the most advanced regions of the world.

PRECIPITATION

• Adequate rainfall throughout the year.
• From cyclonic sources, there is a propensity for a tepid winter or autumn maximum.
• The western edges have the most rainfall because the rain-bearing winds originate in the west.
• Moving eastward from the sea, the amount of rainfall diminishes.

SEASONS

• There are four distinct seasons.
• The long, sunny summers are followed by the roar of the wind-filled autumn.
• Winter is a season marked by overcast skies, foggy mornings, and numerous days with rain brought on by cyclonic depressions.
• The driest and most pleasant season after the gloomy winter is spring, and then the cycle repeats itself.

NATURAL VEGETATION

• The natural vegetation of this climatic type is the deciduous forest.
• In the winter, trees lose their foliage. This modification serves as a defence against winter snow and ice.
• Autumnal or fall-related shedding starts and is dispersed by the winds.
• Some of the common species of temperate hardwood include oak, elm, ash, birch, beech, hornbeam, and poplar.
• In the wetter areas grow willows, alder, and aspen.
• The deciduous trees grow in pristine stands and have significant logging value from a business standpoint.
• The sparse undergrowth is useful in logging operations.
• The deciduous hardwoods are great for industrial and fuel uses.
• The conifers, which can endure a higher altitude, a lower temperature, and poorer soils, typically replace the deciduous trees further up the mountains in the Scandinavian highlands, the Rockies, the southern Andes, and the Southern Alps of New Zealand.

9. World Climate: Taiga Climate (Coniferous Forests & Lumbering)

• Taiga Climate is sometimes referred to as the Cool Temperate Continental Climate and is also known as Siberian Climate and Boreal Climate.
• Due to the Southern Hemisphere’s little populated landmass, this sort of climate is primarily seen in the Northern Hemisphere.
• Koppen has defined the Taiga Climatic region as D type in his climatic classification.
• According to Koppen’s classification, the winter temperature can drop below 3 degrees C while the summer months can be pleasant with temperatures over 10 degrees C.

DISTRIBUTION

• It spans central Canada, the majority of central and southern Russia, and certain areas of Scandinavia from 50 to 70 N along a continuous strip.
• Around the Arctic Circle, it combines with the Arctic tundra of Canada and Eurasia to the north or poleward. The “Subarctic climate” is another name for this environment.
• In the south, the climate becomes less severe and merges into the temperate Steppe climate.
• Due to the narrowness of the continents at high latitudes, the Siberian climate is absent in the Southern Hemisphere.
• The Southern Hemisphere’s considerable maritime influence lessens the severity of the winter.

CLIMATE

In the Taiga climate region, the summers can be moderate or cool, while the winters can be quite cold because of the polar and Arctic air masses’ strong winds and snowstorms.

TEMPERATURE

• These areas have exceptionally cold winters that last for a very long time and have temperatures between – 30 C and – 40 C.
• The summers are cool and brief. Spring and autumn are very brief and transitional periods.
• The annual range of temperature is very high, almost 50 C to 60 C.
• The coolest place on earth, Verkhoyansk is situated in this climatic region.
• In this location, significant snowfall and frosts are frequent due to the year-round extremely low temperatures.
• Rivers and lakes are frozen, while arctic winds to the north, like the Buran and Blizzards of Eurasia, blow ferociously.
• Siberian climate zones have extremely scarce populations due to the harsh conditions.

PRECIPITATION

• The interiors have almost no maritime influences, which results in low annual precipitation, often between 38 and 63 cm.
• It falls evenly throughout the year, with a summer peak from convectional rain as the continental interiors heat up.
• In winter, the precipitation is in the form of snow.

NATURAL VEGETATION

• The predominant vegetation of this region is evergreen coniferous forests.
• Conifers are highly adapted to this environment and can resist such harsh conditions.
• The greatest single band of the coniferous forest is the taiga in Siberia.
• The region’s coniferous forests mostly consist of pine, fir, spruce, and larch trees.
• The richest sources of softwood are the coniferous forest belts in North America and Eurasia.

Coniferous forests are of huge commercial value due to the following reasons:

• They occur in pure stands and there exist only a few species.
• Coniferous woods occur at consistent heights, grow straight and tall, and are of moderate density, in contrast to the dense and challenging-to-exploit equatorial rain forests.
• Almost all conifers are evergreen. There is no annual replacement of new leaves as in deciduous trees.
• Evergreens greatly benefit from the low yearly temperatures, with more than half of the year being below the growing-point temperature.
• Conifers have a conical shape, which allows them to live in the subarctic climate.
• The sloping branches discourage snow build-up and provide weak wind support.
• Leaves are small, thick, leathery, and needle-shaped to check excessive transpiration.
• Poorly podzolized soils in the area cause undergrowth because they are highly acidic and leached.
• Evergreen forests don’t have falling leaves, thus there is limited humus development and the leathery needles take a long time to decompose because of the cold temperatures.
• Other obstacles to sparse vegetation include the lack of direct sunshine and the brief summer season.
• Coniferous forests are also found in areas with high altitudes and low temperatures in addition to the continental interiors of high latitudes. In the Himalayas, for instance.

10. World Climate: Laurentian Climate

• The Cool Temperate Eastern Margin climate is also known as the Laurentian climate.
• It is the intermediate between the British and Siberian types of climates.

DISTRIBUTION

• It is found only in two regions and only in the northern hemisphere.
• The climate combines elements of the coastal and continental climates.
• North American region: One region is north-eastern North America including eastern Canada, north-east USA, and Newfoundland.
• Asiatic region: The other region is the eastern coastlands of Asia, including North China, eastern Siberia, Manchuria, Korea, and northern Japan.
• Due to the little amount of continental landmass that extends south of latitude 40 S, the climate is completely missing in the southern hemisphere.
• The only possible regions are in eastern Patagonia.
• However, the Southern Andes obstruct the westerlies, making the area arid rather than continental.
• Only 10 inches of precipitation fall there annually due to its rain-shadow status.

TEMPERATURE

• The climate of this type has cold, dry winters and warm, wet summers.
• Winter temperatures can be well below freezing, and snowfall can reach quite a depth.
• The off-shore cold currents from the Arctic helped to temper down the summers, which are as warm as those in the tropics.

PRECIPITATION

• Rain falls throughout the year.
• The easterly winds from the oceans do, however, bring rain, thus there is a noticeable summer maximum.
• Two-thirds of the annual precipitation is in summer.
• Dry, chilly winds from the interiors of the continent blow during the winter.

NATURAL VEGETATION

• The predominant vegetation in this climate is cool temperate forests.
• Trees thrive best in regions with high rainfall, mild summers, and damp air from fogs.
• Forest tends to be coniferous north of the 50 N latitude.
• South of this latitude, deciduous forests is seen.

11. World Climate: Polar Climate (Tundra & Ice Caps)

• The polar climate has cold climatic conditions all through the year.
• In his climatic classification, Koppen (World climate classification) categorised Polar Climate as E type.
• Koppen (World climate classification) claims that the area’s summer temperature is less than 10 degrees. Polar Tundra and Polar Ice Caps were his additional divisions of the polar climate.

DISTRIBUTION

There are exists of the northern hemisphere and southern hemisphere distributions.

NORTHERN HEMISPHERE

• In the northern hemisphere, the polar climate is mostly found north of the Arctic Circle.
• The ice caps are only found in Greenland and highlands at high latitudes where the ground is always covered in snow.
• The lowlands which are ice-free for a few months have tundra vegetation.
• This comprises the Arctic seaboard of Eurasia, the Greenlandic coastal strip, and the desolate regions of northern Canada and Alaska.

SOUTHERN HEMISPHERE

• The largest single ice cap where the layers of permanent ice are visible in the southern hemisphere is found in Antarctica, an uninhabited continent.

TEMPERATURE

• A very low mean annual temperature characterizes the tundra or polar temperature.
• There are just four months with temperatures above freezing. With the exception of four months, the ground is always frozen.
• Interiors are much colder than in the coastal regions.
• Winters are long and very severe, and summers are cool and brief.
• There are weeks of nonstop darkness outside the Arctic and Antarctic circles.
• Frosts and blizzards that occur are very hazardous to the polar inhabitants.

PRECIPITATION

• In the winter, precipitation primarily takes the form of snow, which is drifting by blizzards.
• Convectional rainfall is generally absent because of the low rate of evaporation and the lack of moisture in the cold polar air.
• In summer, there is a maximum and the precipitation is in the form of rain or sleet.
• Cyclones are felt in the coastal areas and there is a tendency towards a winter maximum.

NATURAL VEGETATION

• In severe environments like that of Tundra, few plants survive.
• The greatest inhibiting factor is the lack of heat and energy.
• The growing season is for less than three months and there are no trees in the tundra.
• Hence only the lowest forms of vegetation are supported like mosses, lichens, and sedges.
• In the more sheltered spots, stunted birches, dwarf willows, and undersized alders struggle to survive.
• In the brief summers when snow melts and the days are warmer and longer, berry bushes and Arctic flowers bloom.
• They are short-lived but they brighten the monotonous polar landscape into Arctic prairies.

The most widely used classification of world climate is the empirical world climate classification scheme developed by Wladimir Koppen.