MODIS

All posts tagged MODIS

Icebergs Near New Foundland

Posted by Michael Folmer on 04/29/2017
Posted in: ABI, Arctic, G16-CH03_0.86_NIR-Veggie, Ice, JPSS, MODIS, News, Uncategorized. Tagged: , , , , , , , , . Leave a comment

One of the fascinating aspects of GOES-16 is how much better the resolution is at higher latitudes, near the limb or edge of the footprint.  Forecasters at the Ocean Prediction Center (OPC) noted how much easier it is to see the ice sheet (when clouds allow) and even the breaking up of this ice into groups of icebergs!

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GOES-16 0.86 um “Veggie” channel depicting sea ice near eastern Canada (New Foundland is in the center of the image). *Preliminary, Non-Operational Data* Click to enlarge.

The 0.86 µm near-infrared “Veggie” channel animation above shows the ice swirling or drifting near Labrador and New Foundland.  The 1-km resolution imagery is more resolved around 2 km at this latitude due to the, yet you can see amazing detail in the ice breaking up and moving around.  Note:  The imagery jump is due to GOES-16 ongoing testing during the beta period.

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Aqua MODIS 0.86 um “Veggie” image of the ice “swirls” off the Labrador coast valid on 04/24/17.  Click to enlarge

The Aqua MODIS image above shows a more nadir view of the ice swirls east of Labrador on 04/24/17.  This image is higher resolution (1 km) than the GOES-16 animation above and provides great details that were not previously available to OPC forecasters.

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North American Ice Service Iceberg Analysis for 04/24/17.  Click to enlarge

The Iceberg Analysis from 04/24/17, shows the extent and number of icebergs that are being tracked this spring.  According to this CBC News article, “about 450 icebergs near the Grand Banks of Newfoundland, up from 37 a week earlier, according to the U.S. Coast Guard’s International Ice Patrol in New London, Connecticut. Those kinds of numbers are usually not seen until late May or early June. The average for this time of year is about 80.”  More than 600 icebergs have been spotted in shipping lanes that made the Titanic unfortunately, famous.  A couple photos are included below.

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(Courtesy of the Canadian Press)

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Posted on twitter courtesy of @oneillyatescbc

Thanks for reading!

Hello Strong Baroclinic Zone

Posted by Michael Folmer on 03/04/2015
Posted in: JPSS, MODIS, RGB, Water Vapor Imagery. Tagged: , , , , . Leave a comment

So, we have all probably noticed that it has been cold lately.  Well, due to the ample snow cover over much of the U.S. at this time, the baroclinic zone is sharpening over the lower Mississippi and Ohio River Valleys this afternoon with the aid of shortwave energy coming out of a cutoff low located over the Southwest U.S.  One of the Ocean Prediction Center forecasters, Tim Collins, noted the strong contrast in temperature on either side of this zone in the RGB Air Mass image from MODIS below.

MODIS RGB Air Mass image of the strong baroclinic zone valid on 03/04/15.

MODIS RGB Air Mass image of the strong baroclinic zone valid on 03/04/15.

Note the orange and purplish coloring to the north (above) of the moisture plume (cirrus, etc).  This delineates the colder, drier air advancing south and east, while to the south (below) of the clouds there is a greenish coloring that denotes warmer mid-tropospheric air associated with a ridge of high pressure aloft over the Gulf of Mexico and Southwest Atlantic.

MODIS Water Vapor image to compliment the RGB Air Mass image valid on 03/04/15.

MODIS Water Vapor image to compliment the RGB Air Mass image valid on 03/04/15.

For contrast, the above image is the ~6.7 um water vapor channel from MODIS.  Notice that north of the moisture plume you can see evidence of the lower tropopause and cold air by the relative smoothing noted in the image (lighter blue coloring due to the enhancement).  To the south of the moisture plume, you can see the dry air at ~400-500 mb associated with the ridge over the Gulf of Mexico.

This baroclinic zone will continue to sharpen overnight and produce a significant snowstorm for many in the central and eastern US into tomorrow.

Thanks for reading!

AWIPS 2: On the Fly GOES/POES Hybrids with VIIRS and MODIS

Posted by Chad Gravelle on 03/28/2014
Posted in: MODIS, VIIRS. Tagged: , , , . 2 Comments

The spatial resolution of infrared (IR) polar imagery (e.g., Suomi NPP VIIRS and MODIS) is currently superior to similar geostationary data over North America (~1km vs 4km). Unfortunately, there are relatively few polar passes a day over the contiguous United States. At best, there would be 2 passes over any one location every 12 hours for each polar satellite. This is one reason why it is challenging to introduce operational forecasters to the advantages in using this imagery.

This will all change over the next year with the National Weather Service’s (NWS) second generation Advanced Weather Interactive Processing System (AWIPS2), and the use of polar imagery will become more and more common within NWS Forecast Offices. This is because AWIPS2 will allow the forecaster to overlay multiple images to create GOES/POES hybrid satellite loops.

In the image below, this capability is shown using IR imagery from GOES-13 (10.7 μm), MODIS (~11.0 μm), and Suomi NPP VIIRS (11.45 μm) between 0615 and 0801 UTC on 28 March 2014 over the Southern Mississippi Valley.

IR imagery from GOES-13 (10.7 μm), MODIS (~11.0 μm), and Suomi NPP VIIRS (11.45 μm) between 0615 and 0801 UTC on 28 March 2014 (click image to enlarge).

IR imagery from GOES-13 (10.7 μm), MODIS (~11.0 μm), and Suomi NPP VIIRS (11.45 μm) between 0615 and 0801 UTC on 28 March 2014 (click image to enlarge).

When polar imagery is available from MODIS or VIIRS, it is overlaid on the GOES imagery which allows the forecaster to take advantage of the greater spatial resolution of the polar imagery. In the example shown above, there are GOES-13 images at 0615, 0631, and 0645 UTC, followed by a VIIRS image at 0655 UTC, two more  GOES-13 images at 0715 and 0731 UTC, a MODIS image at 0740 UTC, and one more GOES-13 image at 0801 UTC. As the forecaster cycles through the images, you can envision how this capability would be beneficial. The increased spatial resolution from MODIS and VIIRS allows important details to be extracted which include the location and strength of updrafts/overshooting tops and the location where new convection is forming on the southwestern flank of the MCS. In addition, when deep convection is present, the parallax (GOES pixels are displaced slightly poleward from their correct position) that occurs with geostationary satellites is magnified and the polar imagery “corrects” the location for the forecaster. To see the full impact of these hybrid images, click on the image for a full resolution version.

AWIPS2 is currently being installed at NWS forecast offices throughout the country. +