AN INTRODUCTION TO LAKEMIP

This project was launched after the Workshop “Parameterization of Lakes in Numerical Weather Prediction and Climate Modelling” held September 18-20, 2008, in St. Petersburg (Zelenogorsk), Russia:

Lake parameterization Workshop, Sept 2008: http://netfam.fmi.fi/Lake08/

Scientists from different research groups (e.g. NWP/RCM, Climate, and Limnology) identified the needs for an intercomparison of existing lake models to simulate not only lake surface temperature (including ice and snow cover) but also the evolution of internal vertical thermal profiles.

Although a number of lake model exists, it has been agreed that one should first focus on few lake models for testing purposes such as these parameterised in atmospheric models (NWP/RCM) thus providing for time varying lower boundary conditions. These tests would ultimately indicate directions for further research and developments.

It is also recognised that a minimum number of issues should be addressed in order to evaluate these lake models and to create a benchmark for the different parameterizations and approaches.

The first reasonable step would imply the intercomparison of single-column (i.e. one-dimensional) lake model forced by heat and momentum fluxes (computed on the basis of observed atmospheric variables) in a stand-alone mode over a fixed number of lake types. The second step would deal with the coupling of these lake models to atmospheric models (either single column as well as 3D NWP and RCMs) in order to cover a broader range of lake conditions.

To focus on the first step, this site is providing for relevant information regarding this intercomparison initiative:

• numerical lake models formulations
• available lake data (Lake Surface Temperatures (LST) and thermal profiles), seasonal ice and snow (thicknesses and covers)
• time series of available atmospheric forcing including surface air temperature, moisture, wind speed and direction, but also when available surface fluxes of incoming downward solar and thermal infrared radiation, as well as sensible and latent heat
• lake depth and morphometry
• light extinction coefficient

When available, this web site will also display some of the key results and important findings about this intercomparison.

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