Dams are a major issue in conservation. While they provide electric power and a certain level of water security, they can also be the cause of massive levels of environmental degradation, including flooding important habitat and disrupting the riparian life such as fish spawning. The pros and cons cause much debate, and there is no better time for that discussion than now, with COP 17 underway in Durban, South Africa.
Zachary Hurwitz from International Rivers writes on Google's Lat-Long blog, "This new Google Earth tour takes viewers on a trip to the world's dam-building hotspots to visualize the effect that large dams have on the climate, river ecosystems, and the communities that depend on them. You can learn about topics such as reservoir emissions, dam safety, and adaptation while visiting real case studies in Africa, the Himalayas and the Amazon. The tour also includes animations, which show how over time melting glaciers in the Himalayas – an effect of climate change – may lead to higher flood and safety risks for communities living downstream of dams. You’ll also plunge under water in one of Brazil's dirtiest reservoirs, the Tucuruí Dam, to see in 3D how rotting organic material creates methane gas, which bubbles up from dam reservoirs to emit greenhouse gases in the tropics."