Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

Turbulent Fluxes and Thermal Convection in a Valley (SALVE)

(1) Dept. Micrometeorology, University of Bayreuth, (2) Institute for Atmospheric Physics, University of Mainz,

(3) University and Research Centre Karlsruhe, Institute for Meteorology and Climate Research

Thomas Foken1, Rafael Eigenmann1

Volkmar Wirth2, Björn Brötz2

Norbert Kalthoff3

Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

The Energy Balance Network during COPS

Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

WP1: Eddy covariance measurements

1. Analysis of Eddy covariance measurements (all sites!) 2. Footprint and internal boundary layers3. Development of a quality code. Data transfer into the

data bank

Important results for other groups

1. Analysis with international compared software TK22. Flux contribution of the relevant surface (in error bars)3. Fluxes with error bars and quality code in (formated)

Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

Analysis of eddy-covariance measurements (all sites!)

Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

WP2: Closure of the surface energy balance

1. Standard investigation of energy balance closure2. Influence of local circulations on energy balance closure3. Correction of the energy balance closure

Important results for other groups

1. Energy balance closure analysis for all sites 2. Energy balance closure correction according to the

Bowen ratio3. For Fußbach site exact correction with local circulations

Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

WP3: Investigation of convection started from the ground

1. Selection of relevant days for further investigation and LES examples

2. Investigation of the convective events3. Investigation of spectral characteristics for convection

Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

Free convectionChange of wind direction

For the Kinzig valley a circulation system in the valley was found that changes the direction by 180° in the morning and the evening. In a short phase during the transition the wind

velocity is nearly zero. Example: Station BT01ETGS (Fußbach), June 19, 2009, IOP 4a

In this short phase when the wind velocity is nearly zero the conditions for free convection are given (z/L < -1). These conditions exist for about 30 % of the days (non-synoptical con-vection).

Example: Station BT01ETGS (Fußbach),

June 19, 2009, IOP 4a

Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

Free convectionChange of wind direction

For the Kinzig valley a circulation system in the valley was found that changes the direction by 180° in the morning and the evening. In a short phase during the transition the wind

velocity is nearly zero. Example: Station BT01ETGS (Fußbach), June 19, 2009, IOP 4a

In this short phase when the wind velocity is nearly zero the conditions for free convection are given (z/L < -1). These conditions exist for about 20 % of the days (non-synoptical con-vection).

Example: Station BT01ETGS (Fußbach),

June 19, 2009, IOP 4a

First results will be presented on:- EGU Vienna, poster session OA 2.1, April, 16- AMS, Turbulence and Boundary Layer, Stockholm, June 9-13

Priority Program SPP 1167 of the DFG

Quantitative Precipitation Forecast

WP3: Investigation of convection started from the ground

1. Selection of relevant days for further investigation and LES examples

2. Investigation of the convective events3. Investigation of spectral characteristics for convection

Important results for other groups

1. Selection of convective events for all sited (approx. 30% of all days in the valleys)

2. Dynamics of the generation of convection in the valley with supporting investigations by LES modeling