However, when experimentally raising CO2 concentrations to anticipated AD 2050 levels, while at the same time exposing plants to the increased drought conditions expected by mid-century due to climate change, Dr. Ainsworth is finding a sharp reduction in photosynthetic rate, resulting in reduced growth rate, and predicted loss of food production in crop plants as the climate and atmospheric CO2 concentrations continue to change. What is a likely explanation for this observation?
