Terrestrial Water Cycle Seminar: Dr. Faisal Hossain (Tenn Tech)

Hosted by the Applications group

Modern dams built since the last century collectively impound surface water anywhere in the range of 6000 to 1000 cubic kilometers. While these artificial reservoirs have significantly increased the average residence time of water on land and consequently impacted the global water cycle, not much is known about the impact these individual dams have on their surrounding climate. Currently, there exists a considerable amount of research where a “top-down” outcome based impact (such as, from future climate projections) on artificial reservoirs has been investigated for impounded river basins. However, the “bottom-up” role played by artificial reservoirs and their associated land use/land cover change on the local hydroclimatology has not received as much attention by the research and engineering communities. Given that land cover plays an important role for climate, it is important to investigate how a large reservoir may trigger systematic change in the local climate as it gradually transforms the surrounding landscape. With particular focus on extreme precipitation patterns, this talk will present recent research on what we have uncovered so far on dams as potential catalyst for altering the distribution of heavy precipitation over impounded basins. The research will present both observational analysis based on long-term global records and numerical modeling of events using mesoscale atmospheric models. The potential impact of this research on conventional dam design and operations for the civil engineering profession will also be cast in light of environmental stewardship for the 21st century. Lastly, the issues needing continuing research and further investigation will also be highlighted.