The American Southwest has been suffering from the largest drought in history, all due to climate change. This is a colossal threat to national security and the entire human civilization.
Precipitation in California is limited to a single, fairly short wet season, with the vast majority of rain and snowfall occurring in the winter months across the state. This delicate balance means that a dry rainy season can have lasting consequences. California is the most populous state and largest agricultural producer in the United States, and as such, drought in California can have a severe economic as well as environmental impact. The historical and ongoing droughts in California are caused by lack of rainfall (or snowfall), higher average temperatures, and drier air masses in the atmosphere. This leads to less water availability in the natural environment and in snowpack, rivers, and reservoirs for human use; these water shortages can have major impacts on agriculture and other water-intensive land uses.
This is all caused by climate change and Amazon deforestation. Securing the Amazon rainforest to secure the future of all of civilization.
In 2013 a group of scientists from the Princeton University published a study suggesting that total deforestation of the Amazon rainforest can strongly exacerbate drought conditions in the western states of the USA. According to the study “an Amazon stripped bare could mean 20 percent less rain for the coastal Northwest and a 50 percent reduction in the Sierra Nevada snowpack, a crucial source of water for cities and farms in California.” Generally, the air in western USA from December to February will be drier.[15][16]
Later studies found that "destruction of tropical forests is disrupting the movement of water in the atmosphere, causing major shifts in precipitation that could lead to drought in key agricultural areas in China, India, and the U.S. Midwest. ” Those include the 3 main tropical rainforest: Amazon, Congo, South-East Asia. 50% of the rain in the Midwest come from water evaporating from the land and the Amazon Rainforest probably providing part of it.[17]