Global drought disturbance monitoring and impacts on net primary productivity at large scales

Background/Question/Methods

Evaluating ecosystem disturbance on the ground is rather straightforward, and even regional disturbances can be monitored by high resolution satellite. But a global analysis of ecosystem disturbance has never been done. We are attempting a global annual disturbance analysis using the MODIS sensor on the Aqua satellite. We analyze 110 millionkm2 each year for abnormal changes in spectral reflectance and land surface temperature maximum. We build a multi-year record of vegetation spectral indices for each pixel so we can infer when an abnormality, or disturbance has occurred. We then can follow recovery rates of from the disturbance in successive years. Most difficult is to identify the type of disturbance at such large scales and in diverse ecosystems.

Results/Conclusions

We will present the logic and current status of this global MODIS Disturbance Index, MGDI, analyzing global disturbances from 2003-2011. We also will evaluate how the disturbance signal impacts the annual NPP over the same time period.