WinTherface – Mass exchange driven by wind and temperature in lake-wetland interfaces

Coordinator

Ana Margarida da Costa Ricardo

CESAM Responsible researcher

Fernando J. Mendes Gonçalves

Programme

Programa Operacional Competitividade e Internacionalização (02/SAICT/2017)

Dates

04/10/2018 - 03/10/2021

Funding for CESAM

46660 €

Total Funding

230978 €

Proponent Institution

IST-ID - Associação do Instituto Superior Técnico para a Investigação e Desenvolvimento

WinTherface addresses the study of thermally driven exchange flows in lake-wetlands interfaces. The project motivation arises from the relevant ecological and environmental impacts of exchange flows in lake-wetland interfaces, playing a key role in the transport of nutrients and pollutants. Despite of the advances on isolated mechanisms, the interaction of buoyancy, drag and wind forces on the hydrodynamics of lakes has been poorly addressed. In particular the wind effect has been neglected regardless of its importance. Moreover, the Water Framework Directive (WFD) and the new EU research framework place emphasis on biodiversity and ecosystem services, compelling its State Members to achieve good statuses of surface water quality. Addressing that research gap and following the WFD recommendations, WinTherface aims at i) gaining scientific knowledge on the processes (mixing promoted by wind and the interaction of buoyancy, drag and wind forces); ii) including this knowledge into a mathematical tool capable of simulating wind and thermally driven exchange flows in lake-wetland interfaces; iii) using the model for societal purposes by establishing guidelines that promote sustainable solutions for water quality enhancement. The main novelties introduced are: i) the detailed study, under controlled conditions, of the mixing induced by wind on thermally driven exchange flows, and ii) the implementation, validation and application of an operational high-performance water quality simulation tool. The strategy to approach the complexity of the subject consists on a strong articulation of field, laboratory and numerical work ensured by a multidisciplinary team, which synergically includes members from two research centres. CESAM’s team is expert in ecology and water quality and has a deep knowledge of Lake Vela (the field worksite) while CERIS team is expert in hydrodynamic processes, laboratory work and numerical modelling with high-performance computing. The field work will provide detailed insight on the seasonal, spatial and daily variation of the aquatic and atmospheric conditions. This data will support the laboratory tests design and the numerical model validation. The laboratory tests, carried out in a specifically designed channel, will allow testing vegetation, temperature variation and wind conditions at adequate scales. Numerically, a water quality module including the parameterization of vertical fluxes will be implemented in an existing hydrodynamics model, STAV-2D, based on the multi-layered time-averaged and depth-integrated shallow-water equations with sediment transport. Thus, the key outputs include: a simulation tool to model hydrodynamics and water quality of lakes and estuarine regions; field, laboratory and numerical databases of velocities and scalar concentrations; WFD compliant recommendations and tools for new design criteria to promote the water quality and ecology of lakes.