Satellite signatures of the JPSS-1 launch

November 18th, 2017 |

Suomi NPP VIIRS Day/Night Band (0.7 µm) image [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) image [click to enlarge]

The JPSS-1 satellite was successfully launched at 0947 UTC (1:47 AM local time) on 18 November 2017 from Vandenberg Air Force Base, California (Spaceflight Now). A Suomi NPP VIIRS Day/Night Band (0.7 µm) image about 22 minutes prior to launch (above; courtesy of William Straka, CIMSS) showed light emitted by the launch facility as well as nearby cites and offshore buoys.

A comparison of 3 consecutive images of GOES-16 Near-Infrared “Snow/Ice” (1.61 µm), Near-Infrared “Cloud Particle Size” (2.24 µm) and Shortwave Infrared (3.9 mm) data (below) revealed the thermal signature of the launch rocket booster engines at 0947 UTC (just west of the California coast). The hot thermal signature is brighter white on the Near-Infrared images, and darker gray on the Shortwave Infrared image. Nearby 09 UTC surface observations are also plotted (KVBG = Vandenberg AFB).

GOES-16 Near-Infrared

GOES-16 Near-Infrared “Snow/Ice” (1.61 µm, left), Near-Infrared “Cloud Particle Size” (2.24 µm, center) and Shortwave Infrared (3.9 mm, right) images, with plots of surface observations [click to enlarge]

Since the GOES-16 Water Vapor bands — Lower-level 7.3 µm, Mid-level 6.9 µm and Upper-level 6.2 µm —  are essentially Infrared bands (which sense the mean temperature of a layer of moisture), a warm thermal signature was evident on all three of the 0947 UTC images (below).

GOES-16 Lower-level (7.3 µm, left), Mid-level (6.9 µm, center) and Upper-level (6.2 µm, right) Water Vapor images, with plots of surface reports [click to enlarge]

GOES-16 Lower-level (7.3 µm, left), Mid-level (6.9 µm, center) and Upper-level (6.2 µm, right) Water Vapor images, with plots of surface reports [click to enlarge]

Read about SSEC scientists’ efforts to calibrate and validate CrIS and VIIRS on JPSS-1 here.

* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *

Lake Superior ship tracks

November 16th, 2017 |

GOES-16

GOES-16 “Red” Visible (0.64 µm, left), Near-Infrared “Snow/Ice” (1.61 µm, center) and Shortwave Infrared (3.9 µm, right) images, with hourly surface wind barbs plotted in yellow [click to play animation]

* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *

GOES-16 “Red” Visible (0.64 µm), Near-Infrared “Snow/Ice” (1.61 µm) and Shortwave Infrared (3.9 µm) images (above) revealed the presence of ship tracks across Lake Superior on 16 November 2017. Aerosols from the exhaust of ships cause a “cloud seeding effect”, which results in a higher concentration of smaller cloud droplets compared to the surrounding unperturbed clouds. These smaller cloud droplets are more effective reflectors of sunlight, resulting in a brighter white signature on the Snow/Ice imagery and a warmer (darker gray) signature on the Shortwave Infrared imagery.

A view of the entire lake — using similar Visible, Snow/Ice and Shortwave Infrared images from the Terra MODIS instrument — is shown below. In addition to the ship tracks, plumes from power plants and/or industrial sites can be seen in southern Ontario, streaming southward near Thunder Bay (station identifier CYQT) and southwestward near Upsala (CWDV); another plume was evident in northeastern Wisconsin, to the southeast of Eagle River (KEGV).

Terra MODIS Visible (0.65 µm), Near-Infrared

Terra MODIS Visible (0.65 µm), Near-Infrared “Snow/Ice” (1.61 µm) and Shortwave Infrared (3.7 µm) images [click to enlarge]

Strong storm off the Pacific Northwest coast

November 13th, 2017 |

* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Nighttime images  of Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) data (above) showed an occluded extratropical cyclone off the coast of the Pacific Northwest at 1050 UTC or 3:50 AM local time on 13 November 2017. This system was producing storm force winds offshore.

A GOES-16 Mesoscale Sector had been positioned over that region, providing imagery at 1-minute intervals — the structure and evolution of the storm could be seen using Lower-level (7.3 µm), Mid-level (6.9 µm) and Upper-level (6.2 µm) Water Vapor imagery (below).

GOES-16 Lower-level (7.3 µm, left), Mid-level (6.9 µm, center) and Upper-level (6.2 µm, right) Water Vapor images [click to play MP4 animation]

GOES-16 Lower-level (7.3 µm, left), Mid-level (6.9 µm, center) and Upper-level (6.2 µm, right) Water Vapor images [click to play MP4 animation]

A more detailed view was provided by GOES-16 “Red” Visible (0.64 µm) images (below), with hourly wind gusts plotted in yellow. Peak wind gusts as high as 89 mph were reported within the Seattle and Portland County Warning Areas.

GOES-16 Visible (0.64 µm) images, with hourly wind gusts plotted in yellow [click yo play MP4 animation]

GOES-16 Visible (0.64 µm) images, with hourly wind gusts plotted in yellow [click yo play MP4 animation]

A comparison of Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images at 2038 UTC or 1:38 PM local time (below) showed a curved cloud band with embedded convective elements moving inland over western Washington and Vancouver Island. Note that the VIIRS instrument will also fly on the JPSS series of satellites.

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Isolated cirrus cloud feature over Louisiana

November 10th, 2017 |

GOES-16 Visible (0.64 µm) images, with surface station identifiers plotted in yellow [click to play MP4 animation]

GOES-16 Visible (0.64 µm) images, with surface station identifiers plotted in yellow [click to play MP4 animation]

* GOES-16 data posted on this page are preliminary, non-operational and are undergoing testing *

An isolated cloud feature moving east-southeastward across Louisiana on 10 November 2017 caught the attention of several people on Twitter — GOES-16 “Red” Visible (0.64 µm) images (above) showed the motion of this cloud during the 1317-2052 UTC period.

In a 3-panel comparison of GOES-16 “Red” Visible (0.64 µm), Near-Infrared “Cirrus” (1.37 µm) and “Clean” Infrared Window (10.3 µm) images (below), the strong signature (bright white) on the 1.37 µm imagery indicated that this feature was a cirrus cloud. The uncharacteristically-warm Infrared brightness temperatures exhibited by this feature were due to the fact that the thin cirrus allowed warmer thermal radiation from the surface to pass through the cloud and reach the satellite detectors.

GOES-16 Visible (0.64 µm, top), Near-Infrared

GOES-16 Visible (0.64 µm, top), Near-Infrared “Cirrus” (1.37 µm, middle) and “Clean” Infrared Window (10.3 µm, bottom) images [click to play MP4 animation]

Rawinsonde profiles from Lake Charles and Slidell, Louisiana at 12 UTC (below) showed the presence of a moist layer aloft (at an altitude around 9.5 km or 31,100 feet) — the cirrus cloud feature likely resided within this moist layer, which would explain why the cloud was slow to dissipate. Air temperatures within this moist layer were in the -40 to -50ºC range, and winds were from the west-northwest at speeds of 30-35 knots (which was consistent with the cloud motion seen on satellite imagery).

Rawinsonde data for Lake Charles and Slidell, Louisiana at 12 UTC on 10 November [click to enlarge]

Rawinsonde data for Lake Charles and Slidell, Louisiana at 12 UTC on 10 November [click to enlarge]

Even with the higher spatial resolution Infrared Window imagery (1 km, vs 2 km at the satellite sub-point for GOES-16) of Terra MODIS (below), the minimum Infrared brightness temperature of the cirrus cloud feature was still a relatively warm -31ºC.

Terra MODIS Visible (0.65 µm), Cirrus (1.375 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Terra MODIS Visible (0.65 µm), Cirrus (1.375 µm) and Infrared Window (11.0 µm) images [click to enlarge]

Another interesting aspect of this small cirrus cloud is that it was casting a shadow to the north (due to the low November sun angle) — and the Terra MODIS Land Surface Temperature product (below) indicated that LST values were about 10 degrees F cooler within the shadow (low to middle 60s F) compared to adjacent sunlit ground (low to middle 70s F). That particular area was not normally cooler in terms of LST values (because of varying vegetation, soil type, a deep lake, etc.), since it did not show up as a cooler feature on the following day.

Terra MODIS Visible (0.65 µm) image and Land Surface Temperature product [click to enlarge]

Terra MODIS Visible (0.65 µm) image and Land Surface Temperature product [click to enlarge]

Additional images and ground-based photos of the cirrus cloud feature can be found on this AccuWeather blog.