UNIVERSITY OF LEICESTER (GB)
Terrestrial ecosystems are a major carbon pool, and so act to mitigate anthropogenic climate change. However, vegetation in these carbon pools are damaged by tropospheric O3, which is formed from anthropogenic NOx and aerosol emissions. Damaged vegetation cannot sequester as much carbon, so this will lead to a degradation of carbon pools, and a worsening of climate change. In addition, O3 exposure also decreases crop yields, and therefore poses a threat to global food security.
Previous investigations into O3 exposure on vegetation have relied on long-term in-situ studies using eddy covariance methods. Such investigations are costly and extremely geographically limited, and do not cover most of the tropics and emerging economies. Additionally, poorly constrained factors such as CO2 fertilisation also increase the uncertainty of derived estimates of O3-related damage.
Satellite datasets from ESA and third-party missions provide long-term global monitoring of atmospheric composition and plant productivity, and could be combined with existing models of land-atmosphere processes to better constrain the rate of degradation of the terrestrial carbon pool, and to provide more useful metrics on crop losses stemming from O3 exposure. This project will analyse satellite datasets of O3, and vegetation indices as well as use the JULES land surface model to assess the extent short-term and long-term O3 exposure decreases the terrestrial carbon sink and decreases crop yields, particularly near megacities where emissions of O3 precursors are most concentrated. These results will be validated against existing in-situ datasets, such as the SoyFACE experiments, along with historical crop yield data.