Slide 24: Change in production drivers
To understand the climate change outputs, it is important to remember the factors that drive change in tree and grass production: water balance (controlled by both rainfall and temperature), CO2, and temperature. The water balance and temperature factors drive production down in the future in this case, while CO2 drives it up. It differs for trees and grass, but note that the climate factors overwhelm the CO2 effect. As you can see, the trends are similar but the extent of the change in drivers differs. For the first scenario, the water balance will drop, and the increasing carbon dioxide will slowly increase the grass production (f(CO2)g), whilst increasing tree production to a greater extent f(CO2)t. The temperature increase will increase grass production f(T)g, and decrease tree production f(T)t. The same drivers are true for the second scenario, but the extent of the drivers is greater.