1. To provide new observational evidence of how droughts, heatwaves and extreme high rainfall events have changed in frequency and intensity during the past three decades and at the global scale.
2. To attribute the causes of These changes (e.g., intensification of the hydrological cycle, the widening of the tropical belt, ocean-atmospheric oscillations, etc.) and gain understanding about their sensitivity to specific climatic and environmental variables.
3. To provide new insights into past global changes in vegetation distribution and dynamics, and uncover the impact of extreme hydrological and climatic events on these vegetation changes.
4. To show if the spatiotemporal variability of past hydrological and climatic extremes from the IPCC climate models agrees with that revealed by the remote sensing data.
5. To test the skill of IPCC climate models at representing the vegetation response to changes in extremes.
6. To rank IPCC climate models on the basis of their skill at representing the evolution of past climate extremes and the subsequent impacts on vegetation.