Abstract:
The First ISCCP Regional Experiments have been designed to improve
data products and cloud/radiation parameterizations used in general
circulation models (GCMs). Specifically, the goals of FIRE are (1) to
improve basic understanding of the interaction of physical processes
in determining life cycles of cirrus and marine stratocumulus systems
and the radiative
... properties of these clouds during their life cycles
and (2) to investigate the interrelationships between the ISCCP data,
GCM parameterizations, and higher space and time resolution cloud
data.
To-date, four intensive field-observation periods were planned and
executed: a cirrus IFO (October 13-November 2, 1986); a marine
stratocumulus IFO off the southwestern coast of California (June
29-July 20, 1987); a second cirrus IFO in southeastern Kansas
(November 13-December 7, 1991); and a second marine stratocumulus IFO
in the eastern North Atlantic Ocean (June 1-June 28, 1992). Each
mission combined coordinated satellite, airborne, and surface
observations with modeling studies to investigate the cloud properties
and physical processes of the cloud systems.
SOFIA (Surface of the Ocean, Fluxes and Interaction with the
Atmosphere) is a research program carried out by French groups from
the Centre de Recherches en Physique de l'Environnement (CRPE),
Laboratoire l'Aerologie (LA)-Toulouse, Centre de Meteorologie Marine
(CMM)-Brest, Institut Francais de Rechercher sur la Mer
(IFREMER)-Brest, Service d'Aeronomie-Paris, and Laboratoire de
Meteorologie Dynamique (LMD)-Palaiseau with cooperation from Centre
National de Recherche Meteorologique (CNRM)-Toulouse.
The scientific objective of SOFIA during ASTEX was the study of energy
transfer (heat, humidity and momentum fluxes) between the sea surface
and the atmospheric boundary layer at scales ranging from the local
scale to the mesoscale (50 km). The general concept of the program was
to develop a measurement strategy based on nested boxes in which
instrumentation would be used to estimate and quantify fluxes. These
instruments, from which flux estimates at different scales would be
measured, were used in connection with satellite measurements to
understand and, hence, to validate the "satellite integration" of
fluxes, particularly in the presence of mesoscale oceanic and
atmospheric structures responsible for spatial inhomogeneity of
fluxes.
The FOKKER F27 aircraft with flux measurement package and the airborne
Lidar Leandre was used during ASTEX. The FOKKER 27 ARAT capabilities
were as follows:
* Turbulence measurements of wind, temperature and moisture. Fast
response sensors located on a nose boom 5m long, which measured
- attack and sideslip angles by mobile vanes and by a five hole probe
(Rosemound 858).
- true airspeed by a Pitot probe
- temperature by a fast response "INSU" probe
- humidity by a Lyman-alpha humidity meter
* Mean state sensors
- Rosemount temperature probe
- Reverse-flow temperature probe
- General Eastern dew point sensor
* Aerosols and cloud microphysics
- 1-D drop size measurements from 0-6000 microns by four
Knollenberg sensors
- 2-D sensor OAP 2DC for drop sizes between 25 and 800 microns
* Liquid water content
- Johnson-Williams sensors
* Radiative measurements, up- and downward
- Longwave (14-40 microns) Eppley radiometers
- Shortwave (0.2-2.8 microns) Eppley radiometers
- Radiances (7.8-14 microns) Barnes PRT5 radiometers
* Chemical measurements(isokinetic veins)
* Pointint backscatter lidar (Leandre)
* Directional reflectances meausrements (POLDER- Polarized Direct
Reflectance) 
