Context: The Pakistan Army is holding a month-long exercise code-named ‘Jidar-ul-Hadeed’ in the Thar Desert. The aim is to prepare for conflict in extreme desert environments.
About the Exercise

• It is the four-week long defensive manoeuvre exercise and is aimed at validating the concept of defence in deserts.
• It is also conducting a multinational naval exercise ‘Aman-2021’ in the Arabian Sea.
• As many as 45 countries, including the U.S., Russia, China and Turkey, will be participating in the exercise.

About Thar Desert

• It also called Great Indian Desert, arid region of rolling sand hills on the Indian subcontinent. 
• It is located partly in Rajasthan state, northwestern India, and partly in Punjab and Sindh (Sind) provinces, eastern Pakistan.
• The Thar Desert covers some 77,000 square miles (200,000 square km) of territory. 

Area

• The Thar Desert is an arid region that covers over 2,00,000 sq km. It forms a natural boundary along the border between India and Pakistan.
• The surface consists of aeolian (wind-deposited) sand that has accumulated over the past 1.8 million years.
• The desert presents an undulating surface, with high and low sand dunes separated by sandy plains and low barren hills, or bhakars, which rise abruptly from the surrounding plains.
• The dunes are in continual motion and take on varying shapes and sizes.
• Barchan, also spelled Barkhan, crescent-shaped sand dune produced by the action of wind predominately from one direction. One of the commonest types of dunes, it occurs in sandy deserts all over the world.
• It is bordered by the irrigated Indus River plain to the west, the Punjab Plain to the north and northeast, the Aravalli Range to the southeast, and the Rann of Kachchh to the south. 
• The subtropical desert climate there results from persistent high pressure and subsidence at that latitude. 
• The prevailing southwest monsoon winds that bring rain to much of the subcontinent in summer tend to bypass the Thar to the east.
• The name Thar is derived from thul, the general term for the region’s sand ridges.

Climate

• The subtropical desert climate there results from persistent high pressure and subsidence at that latitude.
• The prevailing southwest monsoon winds that bring rain to much of the subcontinent in summer tend to bypass the Thar to the east.