Past climate of Rajasthan
Topic: Climate Change: Causes, Evidence and the Global Response · NCERT: Class 11, Ch 11 "World Climate and Climate Change"
Meaning
Rajasthan's past climate shows that a region's climate can change a great deal over thousands of years. The area that is now the Thar desert was wet and cool around 8,000 BC. It was wetter again between 3,000 and 1,700 BC. Since then it has grown steadily drier. This matters because climate shifts like this can shape the rise and fall of human settlements.
Example
Between 2,000 and 1,700 BC, this region was the heartland of the Harappan civilisation. As the land dried out, settlements declined. One explanation offered for the Harappan decline is the 4.2 kiloyear event, a dry spell about 4,200 years ago. A stalagmite from Mawmluh Cave, Meghalaya, records the same event.
Don't confuse with
- Desertification: land degradation in dry areas caused mainly by people, through overgrazing and poor farming, over years or decades. The drying of Rajasthan was a natural climate shift that took thousands of years.