Meridional Ocean Radiation Experiment MORE: First Results

The Meridional Oceanic Radiative Experiment (MORE) is a joint initiative of the P.Shirshov Institute of Oceanology (IORAS) and the Leibniz Institute of Marine Sciences at the University of Kiel (IFM-GEOMAR) with contributions from the UK Met Office and the Meteorological Institute of the University of Bonn. MORE is set up to conduct long-term high quality measurements of surface parameters and fluxes in the Atlantic Ocean with a particular emphasis on short wave (SW) and long-wave (LW) radiation fluxes for proper quantification of the global ocean heat balance. Five MORE cruises have already taken place from 2004 to 2006. In addition to standard meteorological observations of wind, sea surface temperature, air temperature and humidity, meteorological teams on board of the Russian Research Vessels "Vavilov" and "Ioffe" conducted radiation flux measurements using up- and downlooking standard pyranometers and pyrgeometers. Infrared measurements of the skin SST were made by self-calibrating radiometer RAL (SISTeR). Cloud characteristics were recorded by cloud cameras from IFM-GEOMAR. Cloud base height was obtained using the IFM-GEOMAR ceilometer. Observations of vertical temperature and humidity profiles as well as liquid water path from a multi-channel microwave radiometer (IFM-GEOMAR) are planned for 2007 and beyond. Cloud characteristics and top of atmosphere radiative fluxes from the SEVIRI radiometer onboard Meteosat-8 are used to close the energy budget in the atmospheric column along the ship cruises. The paper summarizes the above mentioned cloud, atmosphere and radiation measurements. Improved parameterizations of shortwave and longwave downwelling fluxes have been generated and applied to the International Comprehensive Ocean-Atmosphere Data Set (ICOADS) in order to develop new climatologies of surface radiation fluxes over the global ocean from 1948 onwards.