Aircraft dissipation trails over southern Wisconsin and northern Illinois

October 6th, 2019 |

GOES-16

GOES-16 “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images (above) revealed a series of aircraft “dissipation trails” drifting northeastward across southern Wisconsin and northern Illinois on 06 October 2019. These cloud features were caused by aircraft that were either ascending or descending through a layer of cloud composed of supercooled water droplets — cooling from wake turbulence (reference) and/or particles from jet engine exhaust acted as ice condensation nuclei to cause the small supercooled water droplets to turn into larger ice crystals (many of which then often fall from the cloud layer, creating “fall streak holes“).

A comparison of Suomi NPP VIIRS Visible (0.64 µm), Near-Infrared (1.61 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images (below) helped to confirm the presence of ice crystals within the aircraft dissipation trails: a darker appearance in the 1.61 µm image (since ice is a strong absorber of radiation at that wavelength), and a colder (brighter white) signature in the 3.74 µm image. In the enhancement applied to the 3.74 µm and 11.45 µm images, colors are applied to infrared brightness temperatures of -30ºC and colder — and the shades of yellow represent cloud-top brightness temperatures in the -30 to -39ºC range.

Suomi NPP VIIRS Visible (0.64 µm), Near-Infrared (1.61 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Suomi NPP VIIRS Visible (0.64 µm), Near-Infrared (1.61 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images [click to enlarge]

Several of the “fall streak” clouds were seen in time-lapse videos of west- and east-facing AOSS rooftop cameras (below).

Time lapse of west-facing AOSS rooftop camera images [click to play YouTube video]

Time lapse of west-facing AOSS rooftop camera images (courtesy of Pete Pokrandt, AOSS) [click to play YouTube video]

Time lapse of east-facing AOSS rooftop camera images [click to play YouTube video]

Time lapse of east-facing AOSS rooftop camera images (courtesy of Pete Pokrandt, AOSS) [click to play YouTube video]