USPC CSE 2021Main GS Paper 1
Question 14. Briefly mention the alignment of major mountain ranges of the world and explain their impact on local weather conditions, with examples.
Answer
A mountain range is a series of mountains or hills that are connected or related in position, direction, or origin. They are formed by various geological processes, such as plate tectonics, volcanism, erosion, and glaciation. They have a significant impact on the climate and biodiversity of the regions they are located in, as they affect the patterns of precipitation, temperature, wind, and vegetation.
Some of the most famous mountain ranges in the world are the Himalayas, the Alps, the Andes, the Rockies, and the Great Dividing Range. Each of them has its own unique features and characteristics that make them stand out from the rest. For example, the Himalayas are the highest and longest mountain range in the world, and they are home to many endangered species, such as the snow leopard, the red panda, and the Tibetan antelope. The Alps are the largest and most populated mountain range in Europe, and they are known for their scenic beauty and cultural diversity. The Andes are the longest continental mountain range in the world, and they are rich in natural resources and ancient civilizations. The Rockies are a major mountain range in North America, and they are famous for their diverse wildlife and national parks. The Great Dividing Range is a cordillera system in eastern Australia, and it is the fifth-longest land-based mountain chain in the world.
The alignment of major mountain ranges of the world and their impact on local weather conditions can be briefly explained as follows:
The Himalayas: These are the highest and longest mountain range in the world, extending from Afghanistan to Myanmar in a curved shape. They act as a natural barrier between the Indian subcontinent and the north pole, blocking the cold and dry winds from the north. They also trap the moisture-laden monsoon winds from the south, causing heavy rainfall on their southern slopes and creating a rain shadow effect on their northern slopes. This results in diverse climatic zones, such as tropical, temperate, alpine, and desert, in the regions surrounding the Himalayas.
The Alps: These are the largest and most populated mountain range in Europe, stretching from France to Slovenia in a crescent shape. They influence the precipitation patterns in southern Europe and Eurasia, as they intercept the moist winds from the Atlantic Ocean and the Mediterranean Sea. They also create local winds, such as the foehn, which is a warm and dry wind that blows down the leeward side of the mountains, and the mistral, which is a cold and strong wind that blows from the north through the Rhine Valley.
The Atlas: These are a series of mountain ranges in northwest Africa, extending from Morocco to Tunisia in a southwest-northeast direction. They separate the Mediterranean region from the Sahara Desert, creating a contrast in climate and vegetation. They capture the moisture from the Mediterranean winds, causing high rainfall on their northern slopes and creating a lush green landscape. They also form a rain shadow on their southern slopes, preventing rainfall in the desert region of Sahara.
The Andes: These are the longest continental mountain range in the world, extending from Venezuela to Chile along the western coast of South America. They have a tremendous impact on the climate of the region, as they create different climatic zones along their length and width. The northern part of the Andes is typically rainy and warm, while the eastern part of the central Andes is also wet due to the Amazonian influence. The southwestern part of the Andes is dry and cold, due to the Humboldt Current and the rain shadow effect. The Andes also affect the distribution of flora and fauna, as they create altitudinal gradients of temperature and precipitation.
The Rockies: These are a major mountain range in North America, extending from Canada to New Mexico along the western part of the continent. They have a significant effect on the weather and climate of North America, as they act as a barrier to the moist air masses from the Pacific Ocean. They cause orographic precipitation on their western slopes, creating lush forests and rivers. They also create a rain shadow on their eastern slopes, leading to dry and arid conditions in the Great Plains and the deserts of Southwest North America. They also influence local winds, such as the Chinook, which is a warm and dry wind that melts snow on the eastern slopes of the Rockies.
The Ural Mountains: These are a low mountain range in west-central Russia that forms part of the traditional boundary between Europe and Asia. They run north-south mostly through Russia, from the coast of the Arctic Ocean to the river Ural and northwestern Kazakhstan⁴. They have a relatively minor impact on the climate of Russia, as they are not high or wide enough to block or deflect the prevailing winds from either side. However, they do create some local variations in temperature and precipitation, especially in winter when they act as a barrier to the cold Siberian air masses that move westward⁵. They also provide some shelter
and moisture for the forests and grasslands that grow on their eastern slopes.
The Great Dividing Range: These are a cordillera system in eastern Australia that runs roughly parallel to the east coast of Australia and forms the fifth-longest land-based mountain chain in the world. They have a significant impact on the climate of Australia, as they divide the wetter coastal regions from the drier inland areas. They also create different climatic zones along their length, such as tropical, subtropical, temperate, and alpine. They affect the distribution of rainfall, as they intercept the moist winds from the Pacific Ocean and cause orographic precipitation on their eastern slopes, while creating a rain shadow on their western slopes. They also influence local winds, such as sea breezes, mountain breezes, and valley breezes.