How CO2 helps plants – resources for high school students and teachers


The Science Journal for Kids has recently published an article entitled “How CO2 can help agriculture in the face of climate change”, led by AgMIP researcher and Climate Analytics scientific advisor Dr. Delphine Deryng. The article, which derives from the Deryng et al. (2016) Nature Climate Change article entitled “Regional disparities in the beneficial effects of rising CO2 concentrations on crop water productivity”, brings cutting edge peer-reviewed environmental science research to high-school level students and their teachers.

The intent is to provide up-to-date information about how climate affects agriculture, and the role of modeling in anticipating future conditions. It also provides information on how shifts in atmospheric CO2 levels may impact agricultural productivity. The article includes a glossary and set of questions to test students on their understanding. It is available for download here. An additional teachers key is also available here. UKaid’s Department for International Development (DFID) supported the production of these learning resources through its support to the Agricultural Model Intercomparison and Improvement Project (AgMIP).

CWPImage showing how crop water productivity is calculated (above) and explaining photosynthesis (below). Images from Article

The research is about interactions between CO2 and crop yield for four major global crops: wheat, rice, soybean, and maize. Crop yield and evapotranspiration in a future climate with current CO2 levels and in a future climate with increased CO2 levels were calculated using models to determine crop water productivity (CWP) levels. The current and future calculated CWP levels were then compared to understand how CO2 alone could impact crop production.

The study shows that increased temperatures and climate change will have negative impacts on crop yields. However, the increased level of CO2 will offset some of these negative impacts. In particular, some crops grow better and use less water when higher CO2 concentrations are available. This is especially notable in drier regions of Africa and the Middle East. The study also identifies areas for further study in a new phase of AgMIP research focusing on CO2.

These findings will assist in adaptation planning for future climate change impacts. Crops that are likely to become more efficient in their water use may be allocated less water, with water redirected to land and crop that need more. Knowing that some crops are more efficient in the drier regions will help communities of farmers prepare for the shift. If current crops may be negatively impacted, they can begin to plan for shifts in crops, cultivation, and markets.

“Conveying our latest research findings beyond the scientific community is super important and working with editors at the Science Journal for Kids offered an exciting experience for my co-authors and me” said Deryng. “This is important information to share as today’s students will be the ones contributing tomorrow’s breakthrough research on food production in a changing world.”

The Science Journal for Kids web site includes links to key terms, scientific methods, related high-school level Advance Placement (AP) topics, and teacher resources. The site is supplemented by a NASA video entitled “Science for a Hungry World: Part 6”, featuring AgMIP principal investigator and NASA researcher Cynthia Rosenzweig, together with NASA colleagues Compton Tucker and Molly Brown.