NINA CHESTNEY Reuters 8 Dec 15;
Global warming has not paused, but more research is needed to understand the level that might cause tipping points, or irreversible damage to the earth's climate system, the chair of the U.N. panel of climate scientists told Reuters on Tuesday.
In 2013, the panel reported a slowdown or "hiatus" in warming since about 1998, despite rising man-made emissions of greenhouse gases, heartening skeptics who said the risks of climate change had been exaggerated. However, more recent research by the U.S. National Oceanic and Atmospheric Administration (NOAA) has suggested this hiatus is an illusion.
"There is no hiatus (in global warming). Multiple lines of evidence suggest that the earth is warming," said Hoesung Lee, the 69-year-old South Korean economics professor named chair of the U.N. Intergovernmental Panel on Climate Change (IPCC) in October.
"For instance, the atmospheric concentration of CO2 is rising, sea levels have been rising and the temperature of the ocean has also been rising," he said in an interview. "The important point is we need to look at the trend, not just one year of data."
But Lee, attending the U.N. climate summit in Paris, said more work was needed, based on a number of years of observations, to establish a "clear understanding of the relationship between carbon emissions and economic growth".
Lee will oversee the next cycle of reports from the IPCC, whose most recent findings in 2013-14 concluded that global warming meant risks of "severe, pervasive and irreversible impacts".
He said more study was also needed to understand the importance of tipping points, where, for instance, ice melt becomes irreversible.
"Clearly the most dangerous impacts will be related to crossing over the tipping points," he said.
Any deal done in Paris is almost certain to fall short of a U.N. goal of limiting global temperature rise to below 2 degrees Celsius (3.6 Fahrenheit), which many scientists see as the threshold for avoiding dangerous climate change.
Some countries that are more vulnerable to global warming, such as low-lying island nations, say the temperature rise needs to be limited even further, to 1.5 C (2.7 F).
(Editing by Kevin Liffey)
Global carbon emissions growth to stall in 2015 - research
Nina Chestney, Reuters Yahoo News 8 Dec 15;
PARIS (Reuters) - Growth in global carbon dioxide emissions is expected to slow for a second year running in 2015, in spite of economic growth, after typically rising by around 2 to 3 percent since the turn of the century, according to research published on Monday.
Global carbon emissions edged up by 0.6 percent last year, compared to 2.4 percent annual growth from 2004-2013, said the study by Britain's University of East Anglia (UEA) and the Global Carbon Project, which compiles data from research institutes worldwide.
In 2015, however, the researchers expect global carbon emissions to decline by 0.6 percent to 35.7 gigatonnes - their central projection from a range of -1.6 percent to +0.5 percent.
"These figures are certainly not typical of the growth trajectory seen since 2000 where the annual growth in emissions was between 2 and 3 percent," said Corinne Le Quéré, of the UEA and one of the authors of the study in the journal Nature Climate Change.
"What we are now seeing is that emissions appear to have stalled and they could even decline slightly in 2015," she added.
Other organizations have said that world carbon emissions growth stalled last year, after decades of gains.
The report is published as around 190 countries meet in Paris to agree on what will likely be the strongest global climate pact yet to curb emissions.
It is widely acknowledged that current emissions cut pledges will not be enough to prevent the world's average temperature from rising beyond 2 degrees Celsius (3.6 Fahrenheit) above pre-industrial levels, viewed as a threshold for dangerous and potentially catastrophic changes in the planet's climate system.
Myles Allen, professor of geosystem science at the University of Oxford, said the report showed it was possible for the world economy to grow while reducing emissions, but he said in order to stop temperatures rising, emissions need to peak and then be reduced to zero.
Michael Grubb, professor of international energy and climate change policy at University College London, said: "The trend of rapid global emissions growth has been broken: this keeps 2 degrees C in play....There could hardly be better news to help the Paris conference in its final days."
The UEA and Global Carbon Project said their projection for 2015 is based on available energy consumption data in China and the United States, as well as forecast economic growth for the rest of the world.
"The projected decline (in emissions) is largely down to China's decreased coal use, driven by its economic adjustment," Le Quéré added.
China's emissions have been called into question lately due to difficulties in interpreting its data.
China was still the world's biggest emitter last year, releasing 9.7 billion tonnes of CO2 but its emissions growth is expected to decline in 2015 by 3.9 percent after rising by 1.2 percent last year and 6.7 percent a year for the previous decade, the report said.
Globally, it is unlikely that emissions have peaked for good because many growing economies still rely on coal for energy generation and emissions reductions in some industrialized countries are still very modest, the study said.
Full report: www.nature.com/nclimate/index.html
(Editing by William Hardy)
NINA CHESTNEY Reuters 8 Dec 15;