Geography Of Sikkim
Climate
From deep river valleys no more than 250 meters above sea level to the dizzy heights of Khangchendzonga at 8,586 meters, Sikkim harbors ecosystems of nearly every elevational strata. In a matter of a few hours, one is able to ascend from sweltering tropical heat to cool alpine meadows. Facing the brunt of the North East Monsoon rains, it is also one of the wettest regions in the Himalayas due to its proximity to the Bay of Bengal and the mountain barriers of Northeast India.Summers are extremely humid though not necessarily hot as temperatures vary according to altitude.
In the lower and middle hills (Gangtok, Darjeeling, Kalimpong) the maximum temperatures range between 25 and 28° C. Down in the deep river valleys it can get stuffy but is never unbearably hot.Winters are relatively cold at night but pleasant during the day. In the lower and middle hills (Gangtok, Darjeeling, Kalimpong), night temperatures average 5° C, and day temperatures hover around 15° C. The alpine region of course becomes very chilly, and temperatures remain well below freezing except during moments when sunlight can seep in through the clouds.
The Monsoon winds strike Sikkim between late May and early June, and there is incessant rain all across the state till late September. Around July and August, torrential downpours sometimes last for several days at a stretch. Gangtok has an annual rainfall of 325 cm.
Vegetation
The jungles in the lower parts are lush with creepers and crawlers beneath extensive canopies of tree ferns, plantain, bamboo, and several species of tall trees such as kapok and sal. The gigantic Sal is said to take a hundred years to grow, a hundred years to season, and has a hundred years of use before its decay.
The temperate forests have an interesting variety of trees and include oak, chestnuts, maple, birch, magnolia and rhododendron to name a few. Dendrobium orchids, from the giant hookeriana straddling the yokes of tall trees to the tightly-clustered densiflorum that flowers in a bunch the size of a baseball, can be seen in bloom during summer.
In the soft humid soil amidst moss and shrubs are several terrestrial species, and includes several varieties of Paphiopedilum, the exotic ‘ladies slipper’.And up in the cool temperate reaches where the earth gives way to granite, there is larch, fir, juniper and more rhododendrons. Here in the summertime, the meadows come alive with myriads of wildflowers.