Helicopter-borne sea ice thickness measurements in the Storfjord, Spitsbergen from flight HEM_STJ06_01

Results from electromagnetic induction surveys of sea-ice thickness in Storfjorden, Svalbard, reveal large interannual ice-thickness variations in a region which is typically characterized by a reoccurring polynya. The surveys were performed in March 2003, May 2006 and March 2007 with helicopter- and ship-based sensors. The thickness distributions are influenced by sea-ice and atmospheric boundary conditions 2 months prior to the surveys, which are assessed with synthetic aperture radar (SAR) images, regional QuikSCAT backscatter maps and wind information from the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis dataset. Locally formed thin ice from the Storfjorden polynya was frequently observed in 2003 and 2007 (mean thickness 0.55 and 0.37 m, respectively) because these years were characterized by prevailing northeasterly winds. In contrast, the entire fjord was covered with thick external sea ice in 2006 (mean thickness 2.21 m), when ice from the Barents Sea was driven into the fjord by predominantly southerly winds. The modal thickness of this external ice in 2006 increased from 1.2 m in the northern fjord to 2.4 m in the southern fjord, indicating stronger deformation in the southern part. This dynamically thickened ice was even thicker than multi-year ice advected from the central Arctic Ocean in 2003 (mean thickness 1.83 m). The thermodynamic ice thickness of fast ice as boundary condition is investigated with a one-dimensional sea-ice growth model (1DICE) forced with meteorological data from the weather station at the island of Hopen, southeast of Storfjorden. The model results are in good agreement with the modal thicknesses of fast-ice measurements in all years.

Wetlands in central Siberia from ASAR WS 2003, link to shapefiles

An area in central Siberia (partial coverage of Turukhansky und Yeniseysky districts) was investigated using satellite data. It covers freshwater ecosystems of non-forested peatlands in boreal forests. The satellite data represent the growing seasons of 2003/2004. Microwave data were acquired by the Advanced Synthetic Aperture Radar (ASAR) instrument onboard ENVISAT. The multi-temporal capabilities and resolution (150mx150m in WS mode) of the ASAR wide swath mode enabled the detection of dynamic features >2ha over this vast area. Scatterometer (QuikScat) data could be employed to distinguish hydro-periods. Wetland types have been identified on the basis of seasonal changes in backscatter. Results for peatlands have been compared with Russian forest inventory data which contain information on wetland distribution.

INTERACCIÓN OCÉANO-ATMÓSFERA: SURGENCIA Y GENERACIÓN DE ANILLOS EN LA REGIÓN DE PAPAGAYO

Haciendo uso de datos de AVHRR, de datos de viento dci QuikScat y de una estación meteorológica en la zona de Cuajiniquil en Costa Rica, se ha encontrado una clara relación entre la velocidad de los vientos y el fenómeno de surgencia en Papagayo entre el 14 de diciembre de 2001 y el 5 de abril de 2002. Se observa también un corrimiento notable hacia el norte de los vórtices anticiclónicos formados en Papagayo para finales de febrero de 2002 con respecto a los anillos investigados por Ballestero y Coen en el experimento llevado a cabo en 1996 (Ballestero y Coen, 2004).Abstract: Using daLa from (he AVHRR and QuikScat instruments together with information from a meteorological station located in Cuajiniquil, Costa Rica, a relationship between the wind direction and the shape of the upwelling plume in Papagayo has been obtained for the period 14 December 200110 5 April 2002. The acticyclonic rings formed in Papagayo during the end of February 2002 were located 1.5 degrees to the north of the position of the rings observed by Ballestero and Coen in an experiment carried out in 1996.