Life on Earth under threat from CO2 levels
US: There will be a dramatic global decline in the number of
animal and plant species this century if the world continues to
procrastinate over measures to cut carbon dioxide emissions to limit
climate change, a study has found.
Current CO2 emissions are currently tracking on the highest
trajectory envisaged by climate scientists. That means if nothing is
done to reduce emissions significantly over the coming decades, over
half of common plants and one-third of the animals could see a serious
decline, the study concluded.
Scientists came to the assessment by estimating the current and
future geographical ranges of nearly 50,000 widespread and common
species to see how rising temperatures are likely to affect their
territorial limits as defined by the sort of climate they are adapted to
live in.
Plants, amphibians such as frogs and toads, and reptiles such as
lizards are the groups that are likely to suffer the most from a
changing climate because of their relative vulnerability to rising
temperatures and inability to move rapidly from one territory to
another, the study found.
It is one of the first detailed assessments of how common species
found over wide regions of the world will be able to cope with climate
change. Many of these animals and plants are important because they
perform fundamental “ecosystem services” such as cleaning up water
supplies and decomposing waste produce. “This research predicts that
climate change will greatly reduce the diversity of even very common
species found in most parts of the world. This loss of global-scale
biodiversity would significantly impoverish the biosphere and the
ecosystem services it provides,” said Rachel Warren, of the University
of East Anglia, who led the research.
“We looked at the effect of rising global temperatures, but other
symptoms of climate change such as extreme weather events, pests and
diseases mean that our estimates are probably conservative.
Animals in particular may decline more as our predictions will be
compounded by a loss of food from plants. There will also be a knock-on
effect for humans because these species are important for things like
water and air purification, flood control, nutrient cycling and
eco-tourism.” The study found that prompt and stringent mitigation –
measures to reduce CO2 emissions – could substantially avert the
biodiversity disaster facing the planet.
The quicker these measures are enacted, the more time that plants and
animals will have to adapt to any unavoidable rise in temperatures, says
the study published in the journal Nature Climate Change. “Our research
provides crucial new evidence of how swift action to reduce CO2 and
other greenhouse gases can prevent the biodiversity loss by reducing the
amount of global warming to 2C rather than 4C,” Dr Warren said.
- THE INDEPENDENT |
