Table of contents | |
Advancing Monsoon (The Rainy Season) | |
Retreating/ Post Monsoons | |
Distribution of Rainfall | |
Monsoon as a Unifying Bond | |
Difficult Words |
Formation and Movement
- By early June, a low-pressure system forms over the northern plains, drawing in trade winds from the southern hemisphere.
- Southeast trade winds develop over warm subtropical regions in the southern oceans, crossing the equator and moving southwest towards the Indian peninsula.
- These winds pick up moisture as they pass over warm oceans and bring it to the subcontinent.
The onset of the South West Monsoons
Characteristics of Monsoon Winds
Regional Rainfall Patterns
Monsoon Breaks and Trough Movement
Influence of Tropical Depressions
(The Transition Season)
Monsoon Withdrawal
- In October-November, as the sun shifts southward, the monsoon trough weakens over the northern plains, leading to the development of a high-pressure system.
- The southwest monsoon winds gradually diminish, causing the monsoon to withdraw from the Northern Plains.
- October and November signify a transition from the rainy season to drier winter conditions, marked by clear skies and a shift to drier weather patterns.
October Heat
Cyclonic Activity
Impact of Cyclones
High Rainfall Areas
- The western coast and northeastern India receive more than 400 cm of rainfall annually.
Low Rainfall Areas
- Western Rajasthan, parts of Gujarat, Haryana, and Punjab experience less than 60 cm of rainfall each year.
- The interior of the Deccan Plateau and the eastern side of the Sahyadris also receive low precipitation.
- Leh in Jammu and Kashmir is another area with very low rainfall.
Moderate Rainfall Areas
Rainfall Variability and Its Impacts
Role of the Himalayas
- The Himalayas act as a barrier against extremely cold winds from Central Asia, protecting the Indian subcontinent.
- This protection results in consistently higher temperatures in northern India compared to other regions at similar latitudes.
Impact on the Peninsular Plateau
Monsoon's Unifying Influence
Impact on Indian Life
Cohesion Across Regions
Weather vs. Climate: Weather describes the short-term atmospheric conditions in a specific place at a specific time, while climate refers to the average long-term weather patterns over a significant period, typically 30 years. This distinction helps in understanding daily weather forecasts versus long-term climate patterns.
Temperature Variations: The significant differences in temperature across various regions due to factors like geographical location, altitude, and proximity to water bodies. For example, Rajasthan experiences extreme heat, while Pahalgam in Jammu and Kashmir has moderate summer temperatures.
Precipitation Variations: Differences in the amount and type of precipitation (rain, snow, sleet) that different regions receive based on their climate zones. High variability affects agriculture, water resources, and overall weather patterns.
Climatic Controls: Factors that influence a region's climate, including latitude, altitude, pressure and wind systems, distance from the sea, ocean currents, and relief features. Each of these factors contributes differently to shaping the local climate by affecting temperature, humidity, and precipitation.
Latitude and Climate: The position of a place on the Earth’s surface in relation to the equator (latitude) affects its solar radiation intake, influencing its overall climate. Tropical regions near the equator receive more sunlight and have warmer climates compared to polar regions near the poles.
Altitude's Impact on Climate: Higher altitudes are characterized by thinner air, which can hold less heat, leading to cooler temperatures. This is why mountainous regions typically have colder climates than areas at sea level.
Pressure and Wind Systems: The movement and interaction of different air pressure systems across the Earth influence weather patterns and climatic conditions. For example, high-pressure systems are generally associated with stable and dry weather, while low-pressure systems can lead to storms and rainfall.
Continentality (Distance from the Sea): The effect of an area's distance from the sea on its climate, where areas closer to the sea have milder climates and smaller temperature fluctuations compared to inland areas.
Ocean Currents: Streams of seawater moved by various global wind systems that can significantly influence coastal climates by carrying warm or cold water across different parts of the globe.
Relief Features: Geographic features like mountains that affect climate by blocking wind and precipitation, creating varied weather patterns on their windward and leeward sides.
Monsoon: A seasonal wind system that dramatically influences the climate of regions like India by bringing heavy rains during the summer months. The monsoon is crucial for agriculture but also causes significant weather-related challenges like flooding.
Cyclonic Depressions: Low-pressure areas in the atmosphere that can lead to severe weather conditions, including storms and heavy rainfall, particularly impactful in shaping the seasonal weather patterns in regions like India.
Ferrel's Law: Describes the deflection of wind due to Earth's rotation; in the Northern Hemisphere, winds are deflected to the right, affecting ocean currents and weather systems.
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1. What are the main characteristics of the advancing monsoon season? |
2. When does the retreating monsoon season typically occur? |
3. How is the distribution of rainfall affected by the monsoon season? |
4. How does the monsoon act as a unifying bond in the region? |
5. What are some difficult words related to the monsoon season that are important to understand? |
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