Satellite Nilometers and the Global Commons

 A few months after she received the Nobel memorial prize in 2009  for her studies of the governance of the commons, Elinor Ostrom asked “will lessons from small scale social dilemmas scale up?”   They already have. For nearly fifty centuries, Egyptian farming communities used devices called Nilometers to adapt to the chaotic flow of the Nile. Nilometers enabled passive adaptation to variation in rainfall. In ancient Cambodia, Khmer engineers outdid the Egyptians with a system of active adaptation to climate variation: enormous water storage tanks built by elephants which lasted 400 years, and  are still visible from space. In Bali, polycentric networks of water temples enable hundreds of small-scale irrigation systems to adapt to the availabity of water and the challenge of managing rice pests. However, unbeknown to most farmers, flooded rice paddies emit vast quantities of methane. Fortunately, these emissions can be reduced by ~85% by keeping the paddies mostly dry. We describe a pilot project in which satellite Nilometers inform farmers about emissions from their fields and calculate potential consequences. In this way, they can realign individual incentives with their global implications and trigger adaptation.