Climate | Class 11 Geography Notes

Climate

Climate is defined as the average of weather conditions observed over a long period, typically 30 years or more. Weather refers to the momentary state of the atmosphere at a particular place and time, characterized by elements such as temperature, pressure, wind direction and velocity, humidity, and precipitation. Weather can change quickly within hours or days, whereas climate changes imperceptibly and is noticeable only over decades or centuries. India experiences a hot monsoonal climate, which is typical of South and Southeast Asia, characterized by a seasonal reversal of winds and associated rainfall patterns known as the monsoon. Despite the broad unity of the monsoon climate across India, there are significant regional variations in temperature, rainfall, and wind patterns due to geographical diversity. For example, the climate in Kerala and Tamil Nadu in the south differs markedly from that of Uttar Pradesh and Bihar in the north, even though all have monsoon climates. Temperature extremes in India range from highs of about 55°C in western Rajasthan during summer to lows of about -45°C in Leh during winter. Day-night temperature variations also differ widely; coastal regions like Kerala and the Andaman Islands have small diurnal ranges of about 7-8°C, while desert areas like the Thar experience large variations, with daytime temperatures around 50°C and nighttime temperatures dropping to 15-20°C. Precipitation also varies extensively, with places like Cherrapunji and Mawsynram in Meghalaya receiving over 1080 cm of rainfall annually, while arid regions like Jaisalmer in Rajasthan receive less than 9 cm. Snowfall is restricted to the Himalayan region, while the rest of the country receives rainfall. These variations highlight the complex and diverse nature of India's climate within the monsoon framework.

📊 Diagram: Figure on page 2 showing climatic diversity of India; the weather and climate of different regions of India. For example, the climate of Kerala and Tamil Nadu in the south are so different from that of Uttar Pradesh and Bihar in the north, and yet all of

🔗 Connection: This section sets the foundation for understanding the factors that determine the climate of India, which will be discussed next.