Collaborative Research: An Experimental and Modeling Study of Inverse-Temperature Layer and Its Effect on Evaporation over Water Surfaces

蒸发是地球系统中连接水、能量和碳循环的一个独特的重要过程。监测和模拟湖泊和海洋等水面上的蒸发仍然具有挑战性。更好地对水蒸发进行量化和建模，需要对水-大气界面的物理过程有更好的了解。一个突出的科学问题是温度随深度增加的上层水层，即逆温层，在蒸发中的作用。一个由水文气象学家和流体力学科学家组成的跨学科团队将利用前沿的野外和数值实验技术以及各种建模工具来解决这个问题。这个项目的成果将有利于地球科学的广泛领域，特别是对水-能源-碳循环的研究。这个项目将培养研究生获得全面的研究经验。这3所大学将以追求理工科教育的不同民族高中生和大学生为对象，开展小型项目、系列讲座、暑期研修等活动。该项目的目标是通过野外实验、大涡模拟以及理论和模型分析，了解水体顶部逆温层动力学的物理机制及其对日和季节尺度上水面蒸发的影响。该项目将在一个内陆湖泊上使用一个最先进的科学设施来测量高分辨率的水温剖面、动量/热量/水质量的水上和水中通量以及水文气象变量，以揭示逆温度层的行为。项目团队将进行大涡模拟，以了解大气过程与调节逆温层和蒸发的水中流体动力学/热力学之间的机制联系。该小组还将使用实地和模拟数据来评估陆地-海洋-大气耦合模式中经典和最近开发的蒸发参数化的性能。这些发现将通过期刊论文和会议报告的形式传播给科学界，以促进在地球科学的长期主题和诸如全球内陆水域和相关水生生态系统的碳排放等关键新兴问题上进行更多的合作研究。拟议的工作包括博士生参与研究，将研究成果整合到pi教授的本科和研究生课程中，以及K-12外展。该项目由水文科学和物理与动态气象学项目共同资助。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

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.