International News

PARIS, June 30, (APP/AFP) – Half a degree Celsius
of global warming has been enough to increase heat waves and heavy rains in many regions of the planet, researchers reported Friday.
Comparing two 20-year periods — 1960-79 and 1991-2010 — between
which average global temperatures jumped 0.5 C (0.9 F), scientists found that several kinds of extreme weather gained in duration and intensity.
The hottest summer temperatures increased by more than 1 C (1.8 F)
across a quarter of Earth’s land areas, while the coldest winter temperatures warmed by more then 2.5 C (4.5 F).
The intensity of extreme precipitation grew nearly 10 percent across
a quarter of all land masses, and the duration of hot spells — which can fuel devastating forest fires — lengthened by a week in half of land areas.
These changes were well outside the bounds of natural variability,
according to the study, published in the journal Nature Climate Change.
“We have to rely on climate models to predict the future,” said lead
author Carl-Friedrich Schleussner, a researcher at the Potsdam Institute of Climate Impact Research.
“But given that we now have observational evidence of around 1 C
warming, we can also look at the real-life impacts this warming has brought,” he said in a statement.
In science, observed trends are generally seen as more reliable than
projections, which can vary sharply depending on the assumptions made.
Changes in climate — sometimes defined as “average weather” — can
only be detected across time periods measured in decades or longer.