WP 1: Regionalisation of atmospheric forcing and lake response

Targets     Lead Contractor     Lead Partners    

Task 1.1     Task 1.2     Task 1.3     Task 1.4    

Targets

In this workpackage, we characterise the different climate/weather patterns that occur within and between mountain Lake Districts, and assess lake responses to them. We focus especially on surface water temperature, ice-cover and hydrology, key parameters that influence key biological and chemical processes.

Task 1.1: Climate/weather extrapolation

We will use output from consistently gridded models at sub-daily time steps since the 1950s to generate climatic data at those Experimental sites that have had automatic weather stations running since 1997. Having determined climatic transfer functions for the last three years, we will use re-analysis models to reconstruct the climate and weather of the last four decades, and then extrapolate those climatic parameters that are governed by the regional circulation (e.g. geostrophic wind, air-temperature, air-pressure, lapse rate) across all our mountain lakes districts.

Task 1.2: Regionalisation of lake water surface temperature

Although affected by several meteorological driving variables, lake surface water temperature can be linked empirically to air temperature alone. However, this link is not always straightforward and needs to be investigated using additional field data. Miniature thermistors with an integrated data logger and infra-red data downloading will be deployed in selected lakes (20-30 for each Lake District), covering altitudinal gradients and different topographical shading.

Task 1.3.: Modelling ice cover

Ice-cover plays a key role in both the biogeochemistry of mountain lakes and in habitat distribution, and it even constitutes a habitat itself. It is necessary to model the timing of freeze-up and break-up, and the thickness of the ice, snow and slush cover. Existing ice models developed to cope with non-heterogeneous thawing will be incorporated into an already existing physical lake model developed by one of the partners, and applied at Experimental sites before use for regionalisation.

Task 1.4.: Catchment hydrology

Techniques for measuring and modelling catchment hydrology in mountain lakes cannot be simply transferred from lowland catchments. However, following recent work in the Austrian Tyrol we will use state of the art techniques including logger-equipped gauges and tracer experiments to verify model calculations for all components of the hydrological cycle at our Experimental sites. We will then use models to assess hydrological variability at the regional scale.

Lead Contractor

1. UEDIN - Geology Department, University of Edinburgh, UK

Lead Partners

• EAWAG - Department of Environmental Physics, Eidgenoessische Anstalt fur Wasserversorgung, Abwasserreinigung und Gewaesserschutz, Dubendorf, Switzerland

• UIBK-IMG - University of Innsbruck, Institute of Meteorology & Geophysics, Austria

• UIBK-IZL - University of Innsbruck, Institute of Zoology & Limnology, Austria