Evaporation is a uniquely important process in the Earth System linking water, energy, and carbon cycles. Monitoring and modeling evaporation over water surfaces such as lakes and oceans remains challenging. Better quantification and modeling of water evaporation requires improved understanding of the physical processes across the water-atmosphere interface. An outstanding scientific question is the role of the top water layer where temperature increases with depth, known as the inverse-temperature layer, in evaporation. An interdisciplinary team of hydro-meteorologists and fluid mechanics scientists will use cutting-edge field and numerical experiment technology and various modeling tools to address this question. The outcomes from this project will benefit broad fields of the Earth Sciences, especially the study of water-energy-carbon cycles. This project will train graduate students to gain all-around research experience. The three participating universities will offer mini projects, seminar series, and summer training courses for high school and college students with diverse ethnic backgrounds pursuing science and engineering education.
The project objective is to understand the physical mechanisms underlying the dynamics of the inverse-temperature layer on the top of water-bodies and its effect on evaporation over water surfaces at diurnal and seasonal scales through field experiments, large-eddy simulations, and theoretical and modeling analysis. The project will use a state-of-the-science facility over an in-land lake to measure high-resolution water temperature profiles, above- and in-water fluxes of momentum/heat/water mass and hydro-meteorological variables to reveal the behavior of the inverse temperature layer. The project team will conduct large-eddy simulations to understand the mechanistic links between atmospheric processes and in-water fluid dynamics/thermodynamics regulating the inverse temperature layer and evaporation. The team will also use field and simulation data to evaluate the performance of classical and recently developed parameterizations of evaporation in coupled land-ocean-atmosphere models. The findings will be disseminated to scientific communities through journal papers and conference presentations to promote more collaborative research on both long-lasting topics of geosciences and critical emerging issues such as carbon emissions from global inland waters and associated aquatic eco-systems. The proposed work includes engagement of PhD students in research, integration of research findings into undergraduate and graduate courses taught by the PIs, and K-12 outreach.
This project is co-funded by the Hydrologic Sciences and Physical and Dynamic Meteorology programs.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.