Global Warming: Plants May Absorb More Carbon Dioxide Than Previously ThoughtVo

Global Warming: Plants May Absorb More Carbon Dioxide Than Previously Thought
   Global warming may not be damaging the Earth as quickly as feared after scientists found that plants can soak up more carbon dioxide than previously thought.
   According to researchers, climate models have failed to take into account that when carbon dioxide increases in the atmosphere, plants thrive, become larger, and are able to absorb more carbon dioxide.
   As part of the carbon cycle, plants use light in photosynthesis, turning carbon dioxide into carbohydrate to grow and releasing oxygen as a waste product.
   Now a team at Wyoming University has found that carbon dioxide stays in leaves longer than previously thought, acting as a fertilizer and accelerating plant growth.
   "The terrestrial biosphere may absorb more carbon dioxide than previously thought," said lead author Professor Ying Sun, of Wyoming University. The scientists say it explains why levels of carbon dioxide in the atmosphere are not rising as quickly as models predict.
   The team estimates that climate scientists have underestimated the ability of plants to grow and absorb carbon dioxide by as much as 16 percent.
   The finding may mean that it will be easier to fulfill the target of keeping global warming below two degrees since pre-industrial times. The Earth has currently warmed 0. 85 degrees Celsius from 1880.
   It was originally thought that vegetation on Earth currently removes one quarter of all human emissions. But the new study suggests it is far higher.
   Dr Chris Huntingford, Climate Modeller at the Center for Ecology and Hydrology, said: "This new paper suggests plants are slightly better at capturing carbon dioxide than we thought.
   " It will be slightly easier to fulfill the target of keeping global warming below two degrees — but with a big emphasis on ’ slightly’.
   " Overall, the cuts in carbon dioxide emissions over the next few decades will still have to be very large if we want to keep warming below 2 degrees. "
   In August, a final report by the Intergovernmental Panel on Climate Change (IPCC)found that the world faces "severe, widespread and irreversible" effects of climate change unless it takes urgent action to limit global warming by cutting back on burning fossil fuels.
   Extreme weather such as floods, heat waves and droughts are expected to become more common while climate change may even worsen the risk of violent conflicts, the report warned.
   The UN has set a target of limiting global warming to 2 degrees Celsius above pre-industrial levels. But the experts said it appears increasingly likely that target will be missed, leading to more severe impacts.
   Although the new paper gives new hope that the target could be met. But some climate experts urged caution.
   Dr Simon Lewis, Reader in Global Change Science at University College London, said: "This study shows, correctly in my view, that photosynthesis is highly responsive to carbon dioxide, but this is far from the only factor amongst many that will impact the forests of the 21st century and how much carbon they store.
   "The level and speed of greenhouse gas emissions cuts needed to avoid dangerous levels of climate change are not altered by this new study. "
   Prof Peter Cox, Professor of Climate System Dynamics at the University of Exeter, said: " Avoiding two degrees of global warming is a huge challenge for humanity even if this effect is taken into account. "