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Archived - NOAA Satellite Images 

The on-line archive contains three images for each AVHRR scene: 
  1.  A short-wave infrared image (band 2) with land mask, latitude/longitude grid and coast outline for showing clouds, haze and sun-glint. 
  2.  A suspended material image from band 1, with effects of thin cloud and sun-glint reduced using band 2. The image has cloud and land masks, the latitude/longitude grid and coast outline. 
  3.  A thermal image from band 4, with contrast stretched to show thermal water patterns. The image has the cloud cover and land masks, the latitude/longitude grid and coast outline. 

Examples of NOAA near-infrared images

Images like these are used to show patterns of cloud, haze and sun-glint and to correct other images for their effects. In the Arctic summers they provide images of sea ice at a time of low thermal contrast.
thermalcolorbar.jpg (26257 bytes)

Clear Water

Cloud/Fog/Haze

Snow

 near infrared image of Vancouver Island, on June 23,1992 at 16:05 PDT VI199206240108_visi_no11.jpg
This near-infrared image, taken at the same time as the thermal image of Vancouver Island, on June 23,1992 at 16:05 PDT (above) shows where cloud or fog covers the water and prevents the thermal band from showing water temperatures. On this day there is cloud offshore and fog near Port Hardy (green to red or white). Land appears green to red. Snow is white. Cloud-free water appears blue.
near-infrared image of Vancouver Island on May 22,1995 VI199505222100_visi_no14.jpg
This is a near-infrared image of Vancouver Island on May 22,1995 at 21:00 UTC. This shows the locations of cloud and haze which appear here as green to red streaks and are especially visible above the darker water, which is coloured as blue. Land appears green to red, and white where snow lies on the coastal mountains.

Examples of NOAA suspended material images

These images show where water contains scattering particles due to river silt, plankton blooms, or (in the Arctic) broken sea ice. The images are computed from the difference between the signals in bands 1 and 2. Band 1 shows the signal in red light, increased by suspended particles. Forming the difference reduces the signals due to haze, thin cloud or smoke, and sunglint, all of which cause an almost equal increase in the two bands. Suspended particles in water cause only a very small increase in band 2. Land shows a much higher signal in band 2 than 1, blackening it out in the difference images. Thick cloud is also masked to black. Since the spectral properties of different clouds vary, the differencing is not perfect, and in many cases cloud edges appear bright, leading to possible "false alarms" for plankton blooms. Blooms are confirmed if the pattern is consistent over more than a few hours, up to several days. Fire smoke can cause especially strong signals in these images.
thermalcolorbar.jpg (26257 bytes)

Clear water

High concentration of suspended material

suspended material image for Vancouver Island on July 19,1997 at 22:12 UTC VI199707192212_susp_no14.jpg
Vancouver Island on July 19,1997 at 22:12 UTC
This image shows the computed suspended material image from the NOAA 14 satellite. Bright water can be seen in the Fraser River plume (right, in the Strait of Georgia) and in coastal fjords due to glacial silt (top, but harder to see between the digital coastlines). The water off the south-west coast of Vancouver Island is brightened by a major bloom event which can be tracked in a sequence of images through nearly the entire month of July. Cloud is masked to black at the top left, though possibly some bright cloud edges remain visible.

Examples of NOAA thermal images

These samples show the thermal images from band 4. Images like this are used to measure surface temperatures and temperature patterns that are important for fisheries management and for understanding patterns of coastal currents and upwelling. Thermal images also show patterns of Arctic ice during the winter darkness. We aren't currently able to use the thermal images to measure temperature as they are not calibrated and the colour palette is stretched to show the most contrast between the temperatures that are visible.
thermalcolorbar.jpg (26257 bytes)

COLD

black to blue, green, yellow, red, white indicating progressively warmer surfaces.

HOT

thermal image Vancouver Island on July 13, 1996 at 20:58 UTC from NOAA 14 VI199607132058_ther_NO14.jpg
Vancouver Island on July 13, 1996 at 20:58 UTC from NOAA 14.
thermal image San Francisco on December 17,2000 at 14:07 UTC from NOAA 16 SF00012171407_ther_no16.jpg 
San Francisco on December 17,2000 at 14:07 UTC from NOAA 16.
 thermal image of the Beaufort Sea on February 17,1997 at 15:43 UTC from NOAA 12. BS199702171543_ther_no12.jpg
Beaufort Sea on February 17,1997 at 15:43 UTC from NOAA 12.
thermal image Queen Charlotte Islands on March 1,1995 at 20:39 UTC from NOAA 14 QC199503012039_ther_no14.jpg
Haida Gwaii on March 1,1995 at 20:39 UTC from NOAA 14.
thermal image Anchorage, Alaska  on March 1,1998 at 22:54 UTC from NOAA 14 AN199803012254_ther_NO14.jpg
Anchorage, Alaska  on March 1,1998 at 22:54 UTC from NOAA 14
NOAA thermal image Vancouver Island on June 23,1992 at 16:05 PDT VI199206240108_ther_no11.jpg
Vancouver Island on June 23,1992 at 16:05 PDT, showing a meandering stream of cold water moving south from the Brooks Peninsula along the edge of the continental shelf, and winding into an eddy west of Cape Flattery. There is a thin band of cold up-welled water along the Pacific coast of Washington. Warmer water is red, with colder water yellow to green to blue. 
NOAA thermal image Western Canadian Arctic taken at 10:15 PST on December 27 1993 BS199312271906_ther_no09.jpg
Western Canadian Arctic taken at 10:15 PST on December 27 1993 at a season when visible and near-infrared bands show only darkness. The image uses thermal radiation to show patterns of sea ice in the Beaufort Sea and Amundsen Gulf. Open water where the ice has moved apart is near freezing, but relatively warm (red). The ice is colder than the water (red to yellow to green), with the surface of thicker ice coldest (blue). Some land temperatures on Banks Island at the right of the image are even colder (black). In Amundsen Gulf, south of Banks Island, ice has recently broken up. Fainter patterns show where a larger area of thinner (less-cold) ice in Amundsen Gulf formed relatively recently, after ice was cleared (up to the curved boundary in the lower right of the image) into the Beaufort Sea, probably by a wind from the east. Streaks of a relatively warm haze cross the lower left of the image.