A top United Nations climate change expert today underscored the dangers of inaction by global leaders in reversing global warming at a gathering of heads of state and government and other top officials at the world body’s headquarters in New York.
Rajendra K. Pachauri, the Chair of the UN Intergovernmental Panel on Climate Change (IPCC), warned in an address at the opening of the high-level meeting that some one billion people could be impacted by global warming, which will threaten the water supply of people in South Asia, China and Africa.
In the 20th century, the increase in average temperature was 0.74 degrees Centigrade, but the IPCC projects that in this century, the temperature will surge by between 1.8-4 degrees Centigrade.
The resulting melting of glaciers threatens the supply of water, which could impact some 500 million people in South Asia, 250 million people in China and between 75-250 million affected in Africa, Mr. Pachauri noted.
“Some regions are more vulnerable than others,” he said.
Small island nations will become even impacted by sea level rise, storm surges, cyclones and ultimately submergence, while Asian cities situated in mega-deltas, many of which are densely populated, are also increasingly prone to damage.
Climate change could also have dire consequences for plant and animal species, 20 to 30 per cent of which are in danger of extinction if increases in global average temperature exceed 1.5-2.5 degrees centigrade.
While adaptation is inevitable, it alone is not sufficient to stem climate change, Mr. Pachauri said. “We need to bring about mitigation actions to start in the short term even when benefits may arise only in a few decades.”
The costs of mitigation are significantly lower than earlier anticipated, he said. If the concentration of gases could be stabilized at 45-490 parts per million of carbon dioxide equivalent and thus limit the equilibrium to 2-2.4 degrees centigrade, then mitigation would only cost the world less than three per cent of the gross domestic product in 2030.
The time is up for inaction, the IPCC Chair said, calling for new policies to be adopted including technology development, a carbon pricing framework and investment in energy infrastructure.
The fourth instalment of the IPCC working group reports is due to be released in November, Mr. Pachauri told the meeting’s participants. This publication is expected to be a synthesis report and the most “policy-relevant” in the series.