Meaning of Climate
To simply put climate definition is the normal weather in a particular region over a couple of years. Whereas if we define weather, it would be modifications or alterations within a matter of mere hours. It takes thousands and thousands of years just to change any environment. Be that as it may, it is dynamic and increasing at a disturbing rate in the course of recent years. Climate refers to the sum total of weather conditions and variations that take place over long periods of time minimally 3 decades.
Weather Definition
Weather refers to the state of the atmosphere over a neighbourhood at any point in time. The elements of weather and climate are equivalent, i.e. temperature, atmospheric pressure, wind, humidity and precipitation. On the idea of the monthly atmospheric conditions, the year is split into seasons such as:
Winter
Summer
Rainy Seasons
Climatic Controls
Below mentioned are the factors on which the climate of any place depends -
1. Latitude
The amount of solar power received varies consistent with latitude because of the curvature of the shape of the earth.
2. Altitude
As we slowly go up to a higher altitude, we experience a decrease in temperature and even the atmosphere gets less dense as we go up. This is why hills are cooler during summers.
3. Distance From the Sea
The sea has a moderating control on the climate. As the separation from the sea expands, its directing impact diminishes and others experience extraordinary climate. This condition is known as continentality i.e. very hot during summers and really cold during winters.
4. Ocean Currents
The ocean currents along with winds near the shore affect the climate of coastal areas. For example, any coastal area with warm or cold currents flowing past it is going to be warm or cool if the winds are onshore.
5. Relief Features
Relief plays a serious role in determining the climate of an area. High mountains work as boundaries for cold or hot breezes. They may also cause precipitation if they're high enough and dwell the trail of rain-bearing winds. Precipitation is any sort of moisture that falls to the world. It incorporates snow, sleet, rain along with hail.
Factors Affecting India’s Climate
Latitude
The Tropic of Cancer goes through the focal point of the country from Mizoram in the east to Rann of Kachchh in the west. India's climate has qualities of both subtropical and tropical climate
Altitude
India has mountains to the north and also features a vast coastal area where the utmost elevation is about 30 metres. Due to the mountains shielding, the subcontinent encounters similarly milder winters when contrasted with central Asia.
Pressure and Winds
The environment and climatic conditions in India are administered by the accompanying air conditions:
Pressure and surface winds
Upper air circulation
Western cyclonic disturbances and tropical cyclones
Air travels from the high-pressure territory over the southern Indian Ocean, during a south-easterly course, crosses the equator and turns directly towards the low-pressure territories over the Indian subcontinent. These are referred to as the Southwest Monsoon winds. These winds pass the nice and cosy oceans, gather moisture and convey widespread rainfall over the territories of India
Jet streams are quick streaming, restricted, wandering air ebbs and flows in the air.
The Indian Monsoon
The climate of India strongly depends on the monsoon winds. Monsoon is the seasonal change in the wind system. Monsoon is experienced by people living within the tropical and subtropical area roughly between 20° South and 20° North. Below is a detailed explanation of the mechanism of the monsoon:
The shift of the position of Inter-Tropical Convergence Zone (ITCZ) in summer, over the Ganga plain, is additionally referred to as the monsoon-trough during the monsoon season.
The Tibetan plateau gets intensely heated during summer, which ends up in strong vertical air currents and therefore the formation of low over the plateau at about 9 km above water level .
The movement of the westerly airstream to the north of the Himalayas and therefore the presence of the tropical easterly airstream over the Indian peninsula during summer also impacts the Indian Monsoon.
The changes among the pressure conditions over the southern oceans additionally have an effect on the monsoons.
The Onset of the Monsoon and Withdrawal
Monsoon lasts for about 100-120 days usually from early June to mid-September. Once monsoon arrives rainfall also increases and continues on till the end of the monsoon. This sudden increase in rainfall is noted as a "burst" of monsoon.
How Different Parts of India Experiences the Arrival of Monsoon?
By the first week of June, the Southern tip of the Indian peninsula starts to experience monsoon. Subsequently, it proceeds into two – the Arabian Sea branch and also the Bay of Bengal branch.
Usually, by the 10th of June, the monsoon from the Arabian Sea branch reaches Mumbai.
The Bay of Bengal branch arrives in Assam within the 1st week of June.
The Arabian Sea branch then reaches Saurashtra-Kachchh by mid-June, which means that it reaches the central part of the country by mid-June.
Both the Bay of Bengal and the Arabian Sea branch merge over the northwestern part of the Ganga plains.
The Bay of Bengal branch reaches Delhi by the peak of June.
Punjab, Haryana, Eastern Rajasthan and Uttar Pradesh also experience monsoon by the first few weeks of June.
By mid-July, the monsoon reaches Himachal Pradesh and therefore the remainder of the country.
Withdrawal of the Monsoon
The departure of the monsoon begins in the northwestern states of India by early September. By mid-October, it withdraws utterly from the northern 1/2 the peninsula. From north to the south, withdrawal of monsoon takes place from the first week of December to the early week of January. By early December, the monsoon has withdrawn from the remainder of the country.
The Seasons
4 main seasons are often identified in India:
The cold weather season (Winter)
The hot weather season (Summer)
The advancing monsoon (Rainy Season)
The departure of monsoon with regional variation known as transition season.
Let’s discuss each of them in detail:
The cold weather Season (Winter)
In Northern India, Winter begins by mid-November and stays until February. December and January are the coldest months within the northern part of India.
The temperature gradually drops as you go from South to North. Days are warm and nights are cold.
The weather is pleasant low temperatures and humidity coupled with feeble variable winds and clear skies.
The cultivation of "rabi" crops is heavily dependent on this season.
The Hot Weather Season (Summer)
From March to May, the weather season is observed in India. The summer months experience rising temperatures and falling atmospheric pressure within the northern part of the country. A striking feature of the recent weather season is the ‘loo’. Strong, hot, gusty and dry winds which blow during the day over North and Northwestern India are known as Loo.
By the end of Summer, pre-monsoon showers noted as "mango showers" help in early ripening of mangoes.
Advancing Monsoon (The Rainy Season)
South-east trade winds originate over the nice and cozy subtropical areas of the southern oceans. They enter the Indian peninsula after crossing the equator and blow in a southwesterly direction due to the south-west monsoon. The monsoon winds cover the country in a few months. Mawsynram within the southern ranges of the Khasi Hills receives the very best average rainfall within the world.
A phenomenon related to the monsoon is its tendency to possess ‘breaks’ in rainfall. These breaks in monsoon are associated with the movement of the monsoon trough. The trough and its axis make it either move southward or northward and regulate the spatial distribution of rainfall. The frequency and intensity of tropical depressions also determine the quantity and duration of monsoon rains. The monsoon is understood for its uncertainties. The intensity, frequency and duration between dry and wet spells vary.
Retreating/Post Monsoons (The Transition Season)
There is a transition period between hot to dry winter conditions from October to November. Retreating of the monsoon is usually marked by rise in temperature and clear skies. During these changes the nights are cool and pleasant while during the day the temperature is high. Due to the conditions of heat and humidity, the weather becomes rather oppressive during the day. This is often commonly referred to as ‘October heat '. Within the last half of October, the mercury begins to fall rapidly in northern India.
Distribution of Rainfall
Certain parts of Northeast India and western coast receive about 400 cm of rainfall annually.
On the other hand, western Rajasthan, and certain parts of Gujarat, Punjab and Haryana only experience 60 cm of rainfall.
Low rainfall is seen on the East of Sahyadris and the interior of the Deccan Plateau.
Snowfall is restricted to the Himalayan region.
The annual rainfall is very variable from year to year.
Monsoon as a Unifying Bond
It can be clearly seen that the Monsoon influences and unifies the Indian subcontinent. The seasonal change of wind brings about the rhythmic cycle of seasons. The uncertainties of rain and uneven distribution are considerably typical of the monsoons. Through the decades, people from all walks of life, from North to South and from East to west anxiously anticipate the arrival of the monsoon. The entire country is dependent on the monsoon winds as it provides the necessary water needed in the agricultural sector.
FAQs on Climate
1. What is the fundamental difference between climate and weather?
The primary difference between climate and weather lies in the time scale. Weather refers to the state of the atmosphere at a specific place and time, which can change within hours or days. Climate, on the other hand, describes the average weather conditions and variations over a large area for a long period, typically 30 years or more. While they share the same elements like temperature and precipitation, climate represents a long-term pattern.
2. What are the main factors that control the climate of any place?
The climate of any location is controlled by several key geographical factors. These are:
- Latitude: Determines the amount of solar energy received due to the Earth's curvature.
- Altitude: As altitude increases, the atmosphere becomes less dense and the temperature decreases.
- Distance From the Sea: The sea has a moderating effect; locations far from it experience extreme temperatures (continentality).
- Ocean Currents: Warm or cold currents flowing past a coastal area can influence its temperature and climate.
- Relief Features: High mountains can act as barriers for winds and cause precipitation on their windward side.
3. How would you describe the climate of India?
The climate of India is broadly described as having a ‘monsoon’ type. While the Tropic of Cancer divides the country into tropical and subtropical zones, the entire nation's climate is dominated by monsoon winds. The Himalayan mountains to the north play a crucial role by protecting the subcontinent from cold Central Asian winds, resulting in milder winters compared to other regions at the same latitude.
4. What are the four main seasons identified in India based on the monsoon cycle?
Based on the distinct atmospheric conditions created by the monsoon, the year in India is divided into four main seasons:
- The Cold Weather Season (Winter): From mid-November to February.
- The Hot Weather Season (Summer): From March to May.
- The Advancing Monsoon (Rainy Season): From June to September.
- The Retreating/Post Monsoon (Transition Season): From October to November.
5. What are jet streams and how do they influence India's climate?
Jet streams are narrow, fast-flowing currents of air found high in the atmosphere. They play a significant role in India's climate. The westerly jet stream influences the winter weather by steering western cyclonic disturbances that cause rainfall in northern India. In summer, the movement of the westerly jet stream to the north of the Himalayas and the presence of the tropical easterly jet stream over the peninsula are crucial for the onset and progress of the monsoon.
6. Why do hilly areas like Shimla remain cool during summer while the plains get very hot?
This phenomenon is explained by the climatic control factor of altitude. As one ascends to higher altitudes, like in the Himalayas, the atmosphere becomes less dense. A less dense atmosphere is less effective at trapping heat, causing the temperature to decrease. This is why hill stations provide a cool retreat from the intense heat experienced in the lower-altitude plains during the summer months.
7. How does being far from the sea lead to extreme weather in cities like Delhi?
This is due to a condition known as continentality. The sea has a moderating influence on climate, absorbing heat slowly and releasing it slowly. Coastal areas thus have a relatively stable temperature range. As the distance from the sea increases, this moderating effect diminishes. Cities like Delhi, located deep inland, do not experience this effect and therefore have extreme climates: very hot summers and very cold winters.
8. What causes the sudden "burst" of the monsoon?
The "burst" of the monsoon refers to the sudden onset of continuous, heavy rainfall that marks the beginning of the rainy season, distinctly different from the scattered pre-monsoon showers. This happens when the moisture-laden Southwest Monsoon winds arrive at the southern tip of the Indian peninsula around early June. This sudden and violent arrival of rain after the dry summer season is known as the monsoon burst.
9. What is the 'October Heat' and why does this phenomenon occur?
The 'October Heat' is a distinct weather condition experienced during the retreating monsoon season (October-November). It occurs because as the monsoon winds withdraw, the skies become clear and temperatures rise. However, the ground is still moist from the preceding rains. The combination of high temperature and high humidity during the day leads to oppressive and uncomfortable weather, which is commonly known as the October Heat.
10. Beyond just providing water, why is the monsoon considered a unifying bond for India?
The monsoon acts as a unifying bond because the entire country's economic and cultural rhythm is deeply connected to it. Its arrival is eagerly awaited by everyone, from farmers whose agricultural activities depend on it, to the general population seeking relief from summer heat. The seasonal cycle it creates, along with its associated festivals, flora, and fauna, forges a shared experience and dependency that unites people across the diverse Indian landscape.
