Dataset

International Polar Year (IPY) , focusing on the north and south polar regions, is defined to investigate the impact of the ice sheet change on the ocean and climate changes on the habitats in the these regions as the collaborative works over sixty countries for two years from March 1 2007 to March 1 2009. To this goal, world space agencies, i.e., Japan Aerospace Exploration Agency, JAXA, National Aeronautics and Space Administration (NASA), European Space Agency (ESA), Canadian Space Agency (CSA), are observing these regions intensively using their own earth observation satellites. Especially, the JAXA observes the polar regions systematically two to three times a year frequency, using three sensors (PRIMS, AVNIR-2, PALSAR) onboard ALOS, and intends to detect the ice sheet decrease and its timely changes. Since PALSAR is able to observe these regions in dependently the day-night condition nor the weather condition, automatic processing using the high speed computer, browse images and the large scale mosaic with the resolution of 500m can be generated within several days after the data acquisition. By now, we have produced several datasets for these regions. We are now opening the web to the users. This allows the global mosaic for these two Polar Regions every 46 days, and the long-term comparison can detect the change of the ice sheet and the land cover.

While the Synthetic Aperture radar (SAR) is the all weather sensor and is very powerful for observing the earth, the unfocused data (raw data) has only the resolution of 20km x 5 km. Features that the SAR raw signal is modulated by the relative motion between the SAR and the earth surface, enables the compression of the raw data to the resolution of 10m or so. This high resolution processing takes several minutes for 70km x 70km size area and full processing of the all the data acquired by the PALSAR of 1000 scenes to 1500 scenes needs the extra powerful processing system. JAXA/EORC recently developed a new processing algorithm that has 10 times faster processing speed with less resolution of 70 m, and succeeded to quick processing of all the PALSAR data, which are daily received. This enables the imaging of all the PALSAR data and allows the detection of the global earth change. It is very helpful to capture the temporal change of the wide regions in the north and south Polar Regions. This type of low resolution but fast processing image is called as high-speed quick look image or simply browse image.