A study suggests that India’s Thar Desert, known for its arid expanse, could undergo a transformational shift due to the effects of climate change, deserts around the world are predicted to expand as temperatures rise, the Thar Desert could buck the trend and actually turn green over the next century.
Located partly in Rajasthan and partly in the Punjab and Sindh provinces of Pakistan, the Thar Desert covers more than 200,000 square kilometers of land. It is the 20th largest desert in the world and the 9th largest hot subtropical desert in the world.
Several studies have predicted the growth of Earth’s deserts under the influence of global warming. For example, experts estimate that the Sahara desert could expand by more than 6,000 square kilometers per year by 2050.
Using a combination of observations and climate model simulations, the research team found that average rainfall over the semi-arid northwestern regions of India and Pakistan increased by 10-50 percent between 1901 and 2015.
Study shows shift of the Indian monsoon was a key factor contributing to the dry conditions in the western and northwestern regions of India. The researchers suggest that a reversal of this trend, coupled with the westward expansion of today’s Indian monsoon, could radically transform the western and northwestern regions of India into a humid “monsoon” climate.
Transformation could in turn increase food security for the country’s growing population
According to the study’s corresponding author B. N. Goswami of the Department of Physics at Cotton University in Guwahati, understanding the dynamics of the Indian summer monsoon is key to understanding how the climate could green the Thar Desert.
This happens due to the seasonal migration of the rain band or active intertropical convergence zone (ITCZ) from south of the equator across the Indian Ocean in winter to about 25 degrees north in summer over the Indian continent.
Expansion of the warm water pool in the equatorial Indian Ocean caused by climate change has led to a westward shift of the ITCZ. This in turn drives the rain further west over the land in the summer months, phenomenon in Indian monsoon unique and is critical to the potential greening of semi-arid regions in northwest India.
Study highlights trend could lead to significant agricultural and socio-economic changes in the region. The research team, including P. V. Rajesh of the Indian Institute of Tropical Meteorology in Pune, collected weather data from South Asia over the past 50 years.
By analyzing changes in monsoon duration and concentration, they fed historical weather and sea surface temperature data into a climate model to predict future changes under different greenhouse gas scenarios.
The result of study
Analysis suggest that the Indian monsoon is indeed expanding westward, leading to a 10% decrease in average precipitation in the northeast and a 25% increase in the west and northwest over the historical period.
The authors of the study highlight the potential benefits of harvesting this increased rainfall and foresee a substantial improvement in food productivity that could revolutionize the socio-economic landscape of the region.
The researchers said that while this unexpected turn of events presents opportunities, it also raises concerns. As the Thar Desert potentially transforms into a greener landscape, the delicate balance of its ecosystem and the wider implications for the environment and local communities remain the subject of ongoing research.
Reference: https://www.science.org/content/article/great-indian-desert-could-disappear-within-century
