It's known as "the roof of the world," four thousand seven hundred meters above sea level lies the Tibetan Plateau. Its glaciers are the source of many of Asia's most important rivers.
But the ice is melting. Scientists say if that continues at current levels, two-thirds of the plateau's glaciers will likely be gone by 2050, affecting up to 2 billion people in China, India, Pakistan, Bangladesh and Bhutan. Li Yan is from Greenpeace China.
"Glacial melting on the Tibetan plateau should be a climate change alarm bell for global heads of state," said Li Yan of Greenpeace China.
Heads of state and delegates from 196 countries are converging on Paris for the COP21 climate summit, which begins Monday. They'll be trying to reach a binding agreement to limit emissions of carbon dioxide, which scientists say are driving temperatures upward.
Their objective is to limit global warming to no more than 2 degrees Celsius above preindustrial levels by the end of this century. Smita Nakhooda of the Overseas Development Institute said that target is crucial.
"Without that," she said, "we will begin to feel extremely severe impacts of climate change, such as extreme weather events, droughts, flooding and other disruptions to our way of life."
Scientists say we are most likely already starting to feel some of the impact of climate change. 2015 has been the hottest year ever recorded.
There is evidence that warmer temperatures are making storms more intense.
At the Copenhagen summit in 2009, developed nations agreed to provide $100 billion of public and private financing to help developing countries adapt to climate change and develop greener technologies. Nakhooda said the debate has shifted since Copenhagen, and there is hope a deal can be reached.
"Several countries have offered to double their contributions of public finance, so that's all encouraging," she said. "The costs of clean energy deployment have plummeted in recent years, and they've plummeted the fastest in some developing countries."
Several events during the summit have been canceled following the terror attacks in Paris two weeks ago. France has deployed an extra 8,000 police officers on its borders.
Vocabulary
plummet：（价格、水平等）骤然下跌
dioxide：二氧化物