Climate of India
A semi-arid wasteland near Tirunelveli, Tamil
Nadu. Monsoon clouds dump torrents of rain
on lush forests that are only kilometres away
in windward-facing Kerala, but are prevented
from reaching Tirunelveli by the Agas-
thyamalai Range of the Western Ghats
(background).
A scene in Uttarakhand’s Valley of Flowers
National Park. In contrast to Tirunelveli, the
park receives ample orographic precipitation
due to its location in a mountainous
windward-facing region wedged between the
Zanskars and the Greater Himalayas.
The climate of India defies easy generalisa-
tion, comprising a wide range of weather
conditions across a large geographic scale
and varied topography. Analysed according
to the Köppen system, India hosts six major
climatic subtypes, ranging from desert in the
west, to alpine tundra and glaciers in the
north, to humid tropical regions supporting
rainforests in the southwest and the island
territories. Many regions have starkly differ-
ent microclimates. The nation has four sea-
sons: winter (January and February), summer
(March to May), a monsoon (rainy) season
(June to September), and a post-monsoon
period (October to December).
India’s unique geography and geology
strongly influence its climate; this is particu-
larly true of the Himalayas in the north and
the Thar Desert in the northwest. The Him-
alayas act as a barrier to the frigid katabatic
winds flowing down from Central Asia. Thus,
North India is kept warm or only mildly cold
during winter; in summer, the same phe-
nomenon makes India relatively hot. Al-
though the Tropic of Cancer—the boundary
between the tropics and subtropics—passes
through the middle of India, the whole coun-
try is considered to be tropical.
As in much of the tropics, monsoonal and
other weather conditions in India are un-
stable: major droughts, floods, cyclones and
other natural disasters are sporadic, but have
killed or displaced millions. India’s long-term
climatic stability is further threatened by
global warming. Climatic diversity in India
makes the