Do you suppose a day will come when we'll hear good news about climate change? Like maybe in their ongoing research of global warming scientists will miraculously discover a cure for cancer? Right now the news is not surprisingly pretty doom-and-gloom and every day it seems there's something new to fret about.

Case in point: Craig Johnstone, the UN High commissioner for Refugees (UNHCR), is expected to issue a warning to scientists and political leaders today that climate change could displace anywhere from 250 million people all the way up to one billion by 2050. The worldwide increase of temperatures may cause mass migration due to problems such as water shortages, crop failures, starvation and rising sea levels which will likely leave homes flooded beyond repair. Though the effects won't be immediate, Johnstone said they will build up during the next four decades.

He said: "This will be a global-scale emergency, but ... it will take place gradually and over a long period of time. It's the obligation of the people who have the means to be helpful to help. They have an obligation to humanity to help."

In terms of intervention on an international scale, he said,"We're strongly in favour of there being adequate international mechanisms to cope."

Hilary Benn, the Environment Secretary, said a global agreement must be reached. "Climate change is the most serious long-term threat to development in poor countries, and if unchecked millions of people may be forced to migrate to escape the effects of drought, flooding, food shortages and rising sea levels," he said.

» The Independent