section_path: Effects on civilization/Agriculture
section_name: Agriculture
paragraph_text: Agriculture
  
  Snowfall can be beneficial to agriculture by serving as a thermal insulator, conserving the heat of the Earth and protecting crops from subfreezing weather. Some agricultural areas depend on an accumulation of snow during winter that will melt gradually in spring, providing water for crop growth, both directly and via runoff through streams and rivers, which supply irrigation canals. The following are examples of rivers that rely on meltwater from glaciers or seasonal snowpack as an important part of their flow on which irrigation depends: the Ganges, many of whose tributaries rise in the Himalayas and which provide much irrigation in northeast India, the Indus River, which rises in Tibet and provides irrigation water to Pakistan from rapidly retreating Tibetan glaciers, and the Colorado River, which receives much of its water from seasonal snowpack in the Rocky Mountains and provides irrigation water to some 4 million acres (1.6 million hectares).