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Baltex cloud liquid water network: cliwa-net

Objective

Problem to be solved
Improved observations for atmospheric models to detect climate change, understand the present climate and predict climate variability.
Objectives and approach
CLIWA-NET focuses on observations of cloud liquid water and vertical structures, and the evaluation and improvement of model parameterisations. The specific objectives are: implementation of a prototype of a European Cloud Observation Network; development of an adequate observing system for the detection of icing conditions for aircraft; objective evaluation and improvement of state-of-the-art cloud parameterisations for climate and weather forecast models, with a focus on integrated cloud liquid water and vertical structure of clouds; design of a "low cost" microwave radiometer in co-operation with industry (SME); contribute to BALTEX/BRIDGE. The CLIWA-NET project will establish a prototype of a European cloud observing system by co-ordinating the use of existing, ground-based passive microwave radiometers and profiling instruments. In total 12 stations within the BALTEX modelling area will contribute to this network. An unprecedented microwave radiometer calibration campaign will be organised in combination with a regional network (100x100 km2). The data from the ground-based remote sensing instruments will feed high quality cloud information, with high temporal but poor spatial resolution, into the calibration of satellite-based estimates of cloud water content with high spatial resolution. New procedures will be developed to fully exploit the synergy. The retrieved CLIWA-NET data sets will be used for an objective evaluation of the performance of state-of-the-art cloud parameterisation schemes. The focus will be on liquid water path (LWP) and vertical structure of cloud amount and cloud water.
Three lines of research will be pursued:
(i) evaluation of cloud related output from leading European atmospheric models;
(ii) investigation of the sensitivity of model cloud parameters to the employed horizontal grid spacing in the meso-scale range from (1-10 km;
(iii) to develop/improve/test cloud parameterisations and underlying assumptions. The cost and complexity of the available microwave radiometers presently hamper the implementation of an operational network. For this reason, the design of a low-cost operational microwave radiometer by a commercial company is included in this project.
Expected impact
As part of the international Global Climate Observing System, and within BALTEX, the project will make a major contribution to our ability to understand the atmospheric system, with benefits in improved cloud forecasts for the general public, air transport, solar energy, construction industry, and civil protection (floods and droughts). The end users organised in the "CLIWA-NET user's advisory group" will provide suggestions on, and judge the social-economic aspects of the project.

Improved observations for atmospheric models to detect climate change, understand the present climate and predict climate variability.

Expected impacts
As part of the international Global Climate Observing System, and within BALTEX, the project will make a major contribution to our ability to understand the atmospheric system, with benefits in improved cloud forecasts for the general public, air transport, solar energy, construction industry, and civil protection (floods and droughts). The end users organised in the "CLIWA-NET user's advisory group" will provide suggestions on, and judge the social-economic aspects of the project.

Call for proposal

Data not available

Coordinator

ROYAL NETHERLANDS METEOROLOGICAL INSTITUTE
Address
10,Wilhelminalaan 10
3730 AE De Bilt
Netherlands
 

Participants (11)

CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE
France
Address
Avenue De L'europe 10-12
78140 Velizy Villacoublay
 
CHALMERS UNIVERSITY OF TECHNOLOGY
Sweden
Address

439 00 Onsala
 
COUNCIL FOR THE CENTRAL LABORATORY OF THE RESEARCH COUNCILS
United Kingdom
Address
Chilton
OX11 0QX Didcot,harwell,chilton
 
GERMAN WEATHER SERVICE
Germany
Address

14405 Potsdam
 
GKSS - FORSCHUNGSZENTRUM GEESTHACHT GMBH
Germany
Address
Max-planck-straße
21502 Geesthacht
 
HELSINKI UNIVERSITY OF TECHNOLOGY
Finland
Address
5A,otakaari 5A
02015 Espoo
 
RADIOMETER PHYSICS GMBH
Germany
Address
Birkenmaarstrasse 10
53340 Meckenheim
 
RHEINISCHE FRIEDRICH-WILHELMS-UNIVERSITAET BONN
Germany
Address
20,Auf Dem Hügel 20
53121 Bonn
 
SWEDISH METEOROLOGICAL AND HYDROLOGICAL INSTITUTE
Sweden
Address
Folkborgsvägen 1
601 76 Norrköping
UNIVERSITE DE VERSAILLES SAINT QUENTIN EN YVELINE
France
Address
Avenue De L'europe 10-12
78140 Velizy Villacoublay
 
UNIVERSITY OF BERNE
Switzerland
Address
Sidlerstrasse 5
3012 Bern