The first comprehensive report into the human cost of climate change warns the world is in the throes of a "silent crisis" that is killing 300,000 people each year.
More than 300 million people are already seriously affected by the gradual warming of the earth and that number is set to double by 2030, the report from the Global Humanitarian Forum warns.
"Climate change is the greatest emerging humanitarian challenge of our time, causing suffering to hundreds of millions of people worldwide," said the forum's president, former U.N. Secretary-General Kofi Annan.
In a statement accompanying the report's release in London Friday, Annan said that it gave the world a glimpse of a grim future if Member States fail to reach a "global, effective, fair and binding" outcome on climate change at the United Nations Climate Conference in Copenhagen in December.
"I hope that all Member States will go to Copenhagen with the political will to sign up to an ambitious agreement to tackle climate change," he said. "As this report shows, the alternative is greater risk of starvation, migration and sickness on a massive scale."
The report's startling numbers are based on calculations that the earth's atmosphere is currently warming by 0.74 degrees celcius. The Global Humanitarium Forum says that temperatures will rise by almost two degrees celcius, regardless of what's agreed in Copenhagen.
"No matter what," the report concludes, "the suffering documented in this report is only the beginning." A rise of two degrees, it says, "would be catastrophic."
Of the 300,000 lives being lost each year due to climate change, the report finds nine out of 10 are related to "gradual environmental degradation," and that deaths caused by climate-related malnutrition, diarrhea and malaria outnumber direct fatalaties from weather-related disasters.
The vast majority of deaths 99 percent are in developing countries which are estimated to have contributed less than one percent of the world's total carbon emissions.
The report warns climate change threatens all eight of the Milliennium Development Goals, which include eradicating extreme poverty and hunger, and reducing child mortality and the spread of diseases including HIV/AIDS and malaria.
Around 45 million of the 900 million people estimated to be chronically hungry are suffering due to climate change, the report says. Within 20 years that number is expected to double. At the same time food production is expected to fall, driving food prices up 20%.
The countries considered to be most vulnerable are those in the semi-arid dry land belt that runs from the Sahara/Sahel to the Middle East and Central Asia, Sub-Saharan Africa, South and Southeast Asia, Latin America and parts of the U.S., small island states and the Arctic region.
Australia is singled out as the developed country most vulnerable to the direct impacts of climate change, and to the indirect impact of climate stress in neighboring countries. Over the past 15 years, the combination of rising temperature and lower rainfall has produced the worst drought in the country's recorded history.
While developed countries including Australia have committed funds to counter the impact of climate change, the Global Humanitarian Forum says developing nations need a dramatic injection of funds up to 100 times more than is currently available to help them adapt to the changes.
The total economic cost of climate change each year is thought to be $125 billion, although the Forum warns that figure may be too conservative and doesn't take into account the impacts on "health, water supply and other shocks."
The Forum's report comes just six months before the meeting in Copenhagen which aims to forge a post-Kyoto climate agreement for 2012 and beyond. The group says the talks could "well be the last chance for avoiding global catastrophe."
A group of 20 Nobel-prize winning, scientists, economists and writers added their voice to the call for immediate global action after meeting in London this week.
In a statement titled "The St James's Palace Memorandum," the group said the temperature rise must be contained to two degrees celsius if the world is to avoid "unmanageable climate risks."
To do that, they said global carbon emissions must start falling by 2015. They set a benchmark of a 50 percent cut by 2050, which they said could only be achieved if developed nations slash their emissions by 25 to 40 percent by 2020.
They also called for an "unprecedented" partnership between government and business to create low carbon energy infrastructure including "smart grids" to distribute and store renewable energy. And, for a solution to rainforest protection, without which, they said, "there is no solution to tackling climate change."