Climate and Extreme Events: A Hydrologic perspective (Invited)

The analysis of hydrometeorological data records of the past century supports the notion that the warming of the Earth climate during the same period has resulted in the intensification of the hydrologic cycle. This is manifested through an increase in the frequency and magnitude of hydrologic extremes such as floods and droughts.

Addressing the impact of floods and droughts on local and regional and scales will require prediction capabilities at 3 time scales (short, mid, and long term). At the short time scale, the prediction of floods is a major hydrologic challenge. Besides requiring a well-calibrated hydrologic model, one needs accurate and timely Quantitative Precipitation Estimates (QPE) as well as Forecasts (QPF) as inputs to the hydrologic models. At the mid and long term time-scales, traditional hydrologic approaches relied on statistical methods and only recently the use of climate models has been gaining in popularity. However, at these time-scales, the transition from point-based statistical methods to climate models requires major efforts in developing global-scale climatic data sets (e.g., precipitation) at high spatial and temporal resolutions sufficient to revisit the parameters of the statistical methods. This will allow better representation of non-stationarity of extreme events climatology.

This presentation will focus on the current state of our progress in each of the three time scales and use examples from recent studies.