Water is critical to the production of crops. But for years, scientists including Jonathan Proctor, Ph.D. Phys.org.
“Studies analyzing how crop yields respond to temperature and rainfall tend to show that temperature matters much more than water, although from plant physiology we understand that water supply is really important for crops,” said Proctor, a graduate student in the Peter Huibers group at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS). “Solving this puzzle is critical to quantifying how climate change will affect global crop yields.”
The research team had a hypothesis: what if the models were measuring the wrong type of water? Instead of measuring rainfall, as was done in previous studies, the Harvard team used satellites to measure soil moisture around the root zone.
The team found that models that use soil moisture data explain 30% to 120% more variation in crop-to-crop yields over the years than models that rely on precipitation.
“Precipitation and soil moisture can vary quite a lot due to evaporation, infiltration and runoff,” Proctor said.
Using satellite observations of soil moisture along with a statistical approach, the team was able to better separate and understand the individual effects of temperature and water on crops, which are often confused because heat and dryness are highly correlated.
In particular, researchers have found that extreme heat deals less damage yield crops than previously predicted, reducing projected warming losses. But the scientists also found heightened sensitivity to drought and floods.
When it comes to predicting performance Agriculture In a changing climate, consideration must be given to how temperatures and water availability will change. Compared to temperature, changes in water availability will be more regional and seasonal, so regional planning strategies and governance come to the fore in the fight against climate change.