upsc notes

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    Western Disturbances

    Let’s say you are standing in the cold, quiet landscape of North India on a winter morning. The sky is clear, the air crisp, and the fields of wheat stand tall, awaiting their lifeline—rain. But unlike the dramatic monsoon showers that arrive with fanfare, this winter rain comes stealthily, carried by an invisible hand from…

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    Comparison between temperate and tropical cyclones

    At first glance, both tropical and temperate cyclones appear similar — low-pressure systems with strong winds and rainfall.But their origin, structure, dynamics, and impacts are very different. Tropical vs Temperate Cyclones 1. Origin 👉 Think of tropical cyclones as “heat engines” and temperate cyclones as “battlefields of air masses.” 2. Latitude Range 3. Frontal System…

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    Naming of Tropical and Subtropical Cyclones

    Earlier, tropical storms were identified in random ways — by places, objects, or even feast days of saints. But this caused confusion in communication and disaster warnings. 👉 The first systematic step came from Clement Wragg, a Queensland Government Meteorologist (Australia), who used personal names for cyclones between 1887–1907. Today, naming is a formal, scientific,…

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    Characteristics of Tropical Cyclones

    General Characteristics When we talk about cyclones, we usually divide them into two big categories: Here, we focus on tropical cyclones. Unlike their temperate counterparts, they are not uniform or regular. Their size, shape, intensity, and impact differ greatly. But still, some general characteristics help us identify them. Let’s go through these one by one….

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    Temperate Cyclones

    When we hear the word cyclone, we often imagine massive storms near the equator like hurricanes or typhoons. But in reality, the cyclones that dominate the weather of Europe, North America, and much of Asia are not tropical—they are called temperate cyclones. These are also known as: Basic Nature 👉 In short: Temperate cyclones are…

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    Fronts

    Fronts and Frontogenesis Imagine the atmosphere as a huge battlefield where different armies of air are always in motion. These armies are called air masses — large bodies of air that have uniform characteristics like temperature, humidity, and pressure. Now, what happens when two very different air masses face each other? For example: The line…

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    Air Masses

    Imagine you are standing in Rajasthan on a hot summer afternoon — the air feels scorching, dry, and persistent. Now, travel in your mind to the coastal region of Kerala during the monsoon — the air is warm, but moist, heavy with water vapour. Both are examples of air masses — vast bodies of air…

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    Global Distribution of Rainfall

    Rainfall is not evenly distributed across the globe. Some regions receive heavy and consistent rain throughout the year, while others remain dry for extended periods. This variation is due to multiple factors such as proximity to the sea, wind direction, mountains, and altitude. Let’s break down the distribution of rainfall worldwide and explore the different…

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    Rainfall

    Imagine you are standing in an open field on a humid afternoon, feeling the air heavy with moisture. Slowly, the wind picks up, and the sky darkens. You sense the inevitable arrival of rain—but what really happens in the sky before those raindrops touch the ground? Let’s take a journey through the science of rainfall,…