Antarctic clouds from below and above
Amelie Kirchgaessner(1) and Tom Lachlan-Cope(2)
(1) British Antarctic Survey, High Cross, Madingley Road, Cambridge, CB3 0ET, United Kingdom
(2) British Antarctic Survey, Hgih Cross, Madingley Road, Camrbidge, CB3 0ET, United Kingdom
This presentation’s aim is to introduce some of the objectives and proceedings of FOCAS (Forcings from the Ocean, Clouds, Atmosphere and Sea-Ice) which is part of the current programme ACES (Antarctic Climate and the Earth System), a contribution to the British Antarctic Survey’s Strategy GSAC (Global Science in the Antarctic Context). One major aspect within FOCAS is the investigation of clouds and their role in the Antarctic climate system. The two objectives of FOCAS in this respect are the investigation of the formation and development of Antarctic clouds using detailed in-situ microphysical observations, and to develop a climatology of cloud coverage and properties over Antarctica using the new generation of satellite-borne instruments (MODIS, GLAS, CALIPSO), validated with in-situ observations.
In a first step data from the US NOAA series of polar orbiting meteorological satellites contained in the ARIES HRPT (Antarctic Reception of Imagery for Environmental Science - High Resolution Picture Transmission) archive will be used for a comparison
(1) with humidity profiles obtained from upper air soundings performed at the British Antarctic bases Halley (76°S, 27°W) and Rothera (68°S, 67°W) and
(2) against information gained from a ceilometer at Halley.
The ARIES receiver has been operated at the British Antarctic Survey base Rothera since February 1993. Upper air soundings are carried out daily at Halley and approximately every three days at Rothera. The ceilometer is in operation since January 2003. With its measurement range of up to 25000ft it delivers directly cloud base heights at up to three levels but the complete backscatter signal from the atmospheric column observed by the ceilometer will also be included in the comparison.
During the conference I hope to present first results of these comparisons and also give an overview over our plans for the validation experiments to be carried out in the Antarctic season of 2006/2007.
Keywords: ESA European
Space Agency - Agence spatiale europeenne,
observation de la terre, earth observation,
satellite remote sensing,
teledetection, geophysique, altimetrie, radar,
chimique atmospherique, geophysics, altimetry, radar,