Comparison of Eastern Himalayas and Western Himalayas

Himalayas are also divided in terms of Eastern and Western Himalayas, the two parts which are different from each other in many ways. The following table makes these important distinctions:

Western Himalayas Eastern Himalayas
  1. Extends till west of River Kali (around 80°E Longitude).
  2. Height of the mountains from the plains in this part rises in a number of stages. The high mountain ranges are at a long distance from the plains
  3. Amount of rainfall here is less and is 1/4th of that of Eastern Himalayas.
  4. The dominant vegetation in the western Himalayas is Coniferous forests and alpine vegetations. The Natural vegetation reflects the impact of lower rainfall.
  5. The altitude of the Western Himalayas is higher than the Eastern Himalayas
  6. Snowline is Lower than Eastern Himalayas
  7. Western Himalayas receive more precipitation from northwest in the winters
  8. Less biodiversity in comparison to eastern Himalayas
  1. This is considered to be ranging from east of the Singalila ranges in Sikkim (88°E Longitudes) to eastern boundaries of Himalayas.
  2. This part rises abruptly from the plains, thus peaks are not faraway from the plains (Example: Kanchenjunga)
  3. This region receives 4 times more rainfall than western Himalayas. Due to high rainfalls, it is covered with dense forests.
  4. Snowline is Higher than Western Himalayas
  5. Eastern Himalayas receive more precipitation from south-eastern monsoon in the summers.
  6. Much ahead from western Himalayas in terms of Biodiversity and is one of the Biodiversity hotspots

Some more observations

  • Western Himalayas are above 36°N Lat. (Mt. Godwin-Austin), and eastern Himalayas are below 28°N Lat. (Kanchenjunga). Thus the 8° difference in the latitude between the two ends of the Himalayas has affected the altitude of the regional snowline so that it is lower in western Himalayas and higher in the east. .
  • The difference in the observed level of the snowline in western and eastern Himalayas is also due to yearly changes in the climatic conditions of the region. In the Himalayas, volume of precipitation changes from year to year, and with that the altitude at which snow falls also changes. In the years of high precipitation, often snow falls at lower altitude than the years of low precipitation.

Northern Slopes and Southern Slopes of Himalayas

The Southern slopes in Himalayan region are covered with thick vegetation, while the northern slopes are generally barren. The reasons are many. The first is that Southern slopes receive more precipitation, as we all know and northern slopes in a rain shadow area. Further, the northern slopes usually receive sun rays only for a few hours during the day at a low angle. The southern slopes receive comparatively vertical rays during the middle of the day. As a result, southern slopes being warmer fall in the area of greater evapotranspiration, and that is why the vegetation is up to a higher altitude in southern slopes. Longer periods of sunshine also have an effect on the volume of snow accumulation on the southern slopes. Due to longer period of sunshine, less snow accumulates on the southern slopes than on the northern slopes. That is why; the snowline on southern slopes is lower in comparison to the northern slopes.

  • Himalayas are oriented east-west and their southern slopes are in direct sunshine for a larger part of the year so the snowline on the southern slopes of the ridges is higher than the northern slopes.
  • Volume of precipitation decreases from the south towards the north, therefore southern ranges in eastern Himalayas have lower snowline than the northern ranges.
  • Volume of precipitation increases with altitude.