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。对湖泊和海洋等水面的蒸发进行监测和建模仍然具有挑战性。要更好地对水蒸发进行量化和建模，就需要更好地了解水-大气界面的物理过程。一个悬而未决的科学问题是顶层水层在蒸发中的作用，在顶层水层中，温度随深度增加，被称为逆温层。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使用尖端的现场和数值实验技术以及各种建模工具来解决这个问题。该项目的成果将惠及地球科学的广泛领域，特别是水-能源-碳循环的研究。该项目将培养研究生获得全方位的研究经验。这三所参与的大学将为不同种族背景的高中生和大学生提供小型项目、研讨会系列和暑期培训课程。该项目的目标是通过现场实验、大涡模拟以及理论和模拟分析，了解水体顶部逆温层动力学的物理机制及其对昼夜和季节尺度水面蒸发的影响。该项目将在内陆湖上使用最先进的科学设施来测量高分辨率的水温分布，动量/热量/水团的水上和水中通量以及水文气象变量，以揭示逆温层的行为。该项目团队将进行大涡模拟，以了解大气过程和水中流体动力学/热力学之间的机械联系，以调节逆温层和蒸发。该团队还将使用现场和模拟数据来评估陆地-海洋-大气耦合模式中经典的和最近开发的蒸发参数的性能。这些发现将通过期刊论文和会议报告向科学界传播，以促进就地球科学的长期主题和关键的新问题(如全球内陆水域和相关水生生态系统的碳排放)开展更多合作研究。拟议的工作包括让博士生参与研究，将研究成果整合到由私人投资机构教授的本科生和研究生课程中，以及K-12外展。该项目由水文科学以及物理和动态气象学项目共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.