Ok, so the name Project Popeye is slightly misleading, as it is not about some sailor eating spinach and having super strength.
During the Vietnam war in the 1960s, US forces attempted to use cloud seeding to make the Ho Chi Minh Trail impassable, in Vietnam, an effort known as Project Popeye (Hambling, 2018).
It failed, but a modern version could do better – or rather, worse, if you are on the receiving end. China is using cloud seeding due to its massive demand for water, with projects that could affect vast areas in its own backyard, as well as neighbouring countries – fuelling tensions.
Following Project Popeye, in 1977 many nations signed up to the Environmental Modification Convention (UN, 1978), banning the use of weather modification for warfare. China joined the treaty in 2005.
Cloud seeding is a type of weather modification that aims to change the amount or type of precipitation that falls from clouds by dispersing substances into the air that serve as cloud condensation or ice nuclei, which alter the microphysical processes within the cloud.
With a number of countries having reached or reaching critical water levels, a number are jumping on the cloud seeding bandwagon.
According to the World Meterological Office, there were 56 countries with cloud seeding projects in 2016, up from 42 in 2011.
Reference
Hambling, D. (2018) China’s Plan to Make it Rain. New Scientist. 12 May 2018, pp.20-21.
UN (United Nations Treaty Collection) (1978) Chapter XXVI: Disarmament. Available from World Wide Web: https://treaties.un.org/Pages/ViewDetails.aspx?src=IND&mtdsg_no=XXVI-1&chapter=26&lang=en. [Accessed: 29 September, 2018].