COPENHAGEN: Time is running out to limit global warming to two degrees Celsius (3.6 degrees Fahrenheit), the United Nation’s climate experts warned on Sunday (Monday in Manila), saying current carbon emissions were a potential path to disaster.
Crowning a landmark review, the Intergovernmental Panel on Climate Change (IPCC) said emissions of three key greenhouse gases were at their highest since more than 800,000 years ago, when mammoths and mastodons roamed the earth.
Earth, it warned, is on a likely trajectory for at least 4 degrees Celsuis warming over pre-industrial times by 2100—a recipe for worsening drought, flood, rising seas and species extinctions.
Many could face hunger, homelessness and conflict in the scramble for precious resources.
UN chief Ban Ki-moon, who in September hosted a special summit on climate change, said: “Human influence on the climate system is clear, and clearly growing.”
“We must act quickly and decisively if we want to avoid increasingly disruptive outcomes,” Ban said, describing it as a “myth” that tackling carbon emissions was costly.
US Secretary of State John Kerry said the report was a fresh warning —“another canary in the coal mine” —while France, which is to host a UN climate conference in December 2015, called for “immediate, all-round mobilization.”
French President Francois Hollande called climate change one of the “big challenges” for the global community and pledged to act for the “wellbeing of the planet.”
IPCC chief Rajendra Pachauri said there remained “little time before the window of opportunity to stay within 2 degrees Centigrade of warming closes.”
“To keep a good chance of staying below 2 degrees Centigrade, and at manageable costs, our emissions should drop by 40 to 70 percent globally between 2010 and 2050, falling to zero or below by 2100,” he added.
Seizing on the report, green groups demanded the phaseout of coal, oil and gas that are driving the carbon problem.
“Renewables and the smart use of energy are the quickest and cleanest ways to cut emissions,” said Greenpeace’s Kaisa Kosonen.
“Any technology that ‘handles’ emissions rather than replaces fossil fuels is like smoking crack to solve an alcohol addiction,” she added.
The first overview by the Nobel-winning organization since 2007 – comes ahead of UN talks in Lima next month to pave the way to a 2015 pact in Paris to limit warming to a safer 2 degrees Centigrade.
But the negotiations have been hung up for years over which countries should shoulder the cost for reducing carbon emissions, derived from the world’s cornerstone energy sources today.
The report said switching to cleaner sources, reducing energy efficiency, and implementing other emission-mitigating measures would be far cheaper than the cost of climate damage.
The bill today for doing this is affordable, but delaying beyond 2030 would cause the cost—and the climate peril—to spiral for future generations.
“Ambitious” carbon curbs would shave just 0.06 percentage points annually from global consumption this century, targeted to grow by 1.6-3.0 percent annually, the IPCC said.
Under the lowest of four emissions scenarios, global average temperatures over this century are likely to rise by 0.3-1.7 degrees Centigrade (0.5-3.1 degrees Fahrenheit), leading to between 26-55 centimeter in sea-level rise.
Under the highest scenario, warming would be 2.6-4.8 degrees Centigrade, causing sea-level rise of 45-82 centimerers.