A new study by the University of California, Irvine and the University of Washington found that climate change has less impact on drought than previously assumed. They found that the plants conserve water in conditions with high carbon dioxide, compensating for the water loss from increasing global temperatures.
As reported by the study now in the Proceedings of the National Academy of Sciences, plants will compensate the water loss in Central Africa and temperate Asia, which includes China, the Middle East, East Asia and most of Russia. As previously estimated, 70 percent of Earth will suffer more droughts due to rising CO2 but now, the new study decreases this down to 37 percent.
When massive amounts of CO2 pollute the atmosphere, the plants take the gas in to cover their stomata. This prevents water from escaping through their stomata, allowing the plants to need less water from the soil.
“This study confirms that drought will intensify in many regions in the future,” says the study’s co-author James Randerson, a professor of Earth system science at UCI. “It also shows that plant water needs will have an important influence on water availability, and this part of the equation has been neglected in many drought and hydrology studies.”
The findings will improve current global climate models that estimate drought in the future. Presently, experts only consider future temperature, humidity and precipitation but according to lead author Abigail Swannthey, an assistant professor of atmospheric sciences at the University of Washington, they now have to also consider the role of the plants.
Still, the team admits that droughts will certainly become more common. While the plants would not need more water, other factors that result from climate change can still negatively impact them. They cite that increasing global temperatures can still make plants more vulnerable to stress and pests.