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| ABOUT POLAR VIEW'S PRODUCTS |
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| Floe edge mapping using Synthetic Aperture Radar (SAR) image |
| A SAR instrument operates in microwave range. It emits pulsed miscrowave signals to a target, and measures the backscattered signal from the target. Since it is an active system that does not rely on solar radiation, images can be acquired at both day and night times. And because microwave can penetrate clouds, it also has the capability to acquire earth surface images at cloudy conditions. This all-time all-weather capability of SAR is advantageous over optical sensors, for which data acquisition is considerably limited by weather conditions.
SAR is sensitive to the changes in target dielectric properties, which is related with the water content, and to the geometric characteristics of the target.
The interaction of radar signal with the ice-air boundary as well as the inhomogeneous ice volume makes SAR a useful tool for the measurements of some ice parameters. It is ideal for timely monitoring of sea ice due to its ability to map ice parameters at both day and night regardless of weather condition. Products posted on this website are floe edge locations mapped from SAR imagery acquired by RADARSAT or ENVISAT ASAR. The figure below is an example.
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| MODIS High Resolution RGB Image |
| MODIS is an optical sensor on board NASA’s polar orbit satellites terra and aqua, which provides daily global coverage. The composite color images posted on this site are generated using images of three MODIS channels. MODIS Channels 2, 1 and 4 are used as R, G, B channels, respectively. This combination uses the two channels with the highest pixel resolution, 250 m, to keep the best spatial information. Channel 4 is re-sampled to 250 m from its original 500 m pixel resolution to match this higher resolution. The images are provided in geotiff format. The MODIS color images posted here provide a visual material for the upper ocean waters, coastal zones, and land areas. An example of the product is shown below. |
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