Researchers at the Leeds Earth and Biosphere Institute are studying the vicious cycle of rainforest loss and climate change. Global warming as a result of burning of fossil fuels and release of other greenhouse gases is causing tropical rainforests to convert to tropical savannah landscapes which hold less carbon. Rainforests are also being lost as a result of habitat destruction from logging, agriculture and other industrial development. This rainforest loss has traditionally and continues to release huge amounts of carbon from dead vegetation, which in turn is causing more climate change. This is one example of a positive feedback that may cause global warming to become abrupt, runaway and deadly. And it is why the Climate Ark and Ecological Internet's Rainforest Portal and Forests.org web sites are dedicated to ending deforestation.