Blowing dust off the coast of Namibia and South Africa

August 7th, 2020 |

VIIRS True Color RGB images from Suomi NPP and NOAA-20 [click to enlarge]

VIIRS True Color RGB images from Suomi NPP and NOAA-20 [click to enlarge]

A sequence of 3 VIIRS True Color Red-Green-Blue (RGB) images from Suomi NPP and NOAA-20 as visualized using RealEarth (above) showed plumes of blowing dust moving off the coast of Namibia and South Africa on 07 August 2020.

EUMETSAT Meteosat-11 Visible (0.6 µm) images (below) displayed the motion of the dust plumes during the daytime hours.

Meteosat-11 Visible (0.6 µm) images [click to play animation | MP4]

Meteosat-11 Visible (0.6 µm) images [click to play animation | MP4]

A plot of surface data from Luderitz, Namibia (station identifier FYLZ) is shown below; it indicated that winds gusted to 36 knots (41 mph) at 08 UTC.

Plot of surface data from Luderitz, Namibia [click to enlarge]

Plot of surface data from Luderitz, Namibia [click to enlarge]

H/T to Santiago Gassó for bringing this event to our attention.

Fire signatures following a large explosion in Beirut, Lebanon

August 4th, 2020 |

Suomi NPP VIIRS Day/Night Band (0.7 µm), Near-Infrared (1.61 µm and 2.25 µm), Shortwave Infrared (3.75 µm) and Active Fires product (credit: William Straka. CIMSS) [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm), Near-Infrared (1.61 µm and 2.25 µm), Shortwave Infrared (3.75 µm) and Active Fires product (credit: William Straka. CIMSS) [click to enlarge]

A sequence of Suomi NPP VIIRS Day/Night Band (0.7 µm), Near-Infrared (1.61 µm and 2.25 µm), Shortwave Infrared (3.75 µm) and Active Fires product at 2335 UTC on 04 August 2020 (above) showed nighttime reflective and thermal signatures of the fire that was burning about 8.5 hours following a large explosion that occurred at 1508 UTC in Beirut, Lebanon.

Plots of Spectral Response Functions (SRFs) for similar spectral bands on the GOES-R series ABI instrument (1.61 µm, 2.24 µm and 3.9 µm) are shown below — note that the 1.61 µm and 2.24 µm SRF curves are located close to the peak emitted radiance of very hot features such as large fires.

Plots of Spectral Response Functions for GOES-R series ABI 1..61 µm, 2.24 µm and 3.9 µm spectral bands [click to enlarge]

Plots of Spectral Response Functions for GOES-R series ABI 1..61 µm, 2.24 µm and 3.9 µm spectral bands (credit: Mat Gunshor, CIMSS) [click to enlarge]

EUMETSAT Meteosat-8 Visible (0.8 µm) images (below) showed a subtle signature of the explosion cloud as it slowly spread out to the northwest, west and southwest before sunset. Station identifier OLBA is Beirut  Rafic Hariri International Airport.

Meteosat-8 Visible (0.8 µm) images [click to enlarge]

Meteosat-8 Visible (0.8 µm) images [click to enlarge]

Cyclone Amphan in the Bay of Bengal

May 18th, 2020 |

Meteosat-8 Infrared Window (10.8 µm) images [click to play animation | MP4]

Meteosat-8 Infrared Window (10.8 µm) images [click to play animation | MP4]

EUMETSAT Meteosat-8 Infrared Window (10.8 µm) images (above) showed Cyclone Amphan during the period when it was rapidly intensifying to a Category 5 storm (ADT | SATCON) by 06 UTC on 18 May 2020. In fact, Ampham became the strongest tropical cyclone on record in the Bay of Bengal basin.

NOAA-20 VIIRS True Color Red-Green-Blue (RGB) and Infrared Window (11.45 µm) images as viewed using RealEarth (below) provided a more detailed view of Amphan shortly before the time of its peak intensity.

NOAA-20 VIIRS True Color RGB and Infrared Window (11.45 µm) images [click to enlarge]

NOAA-20 VIIRS True Color RGB and Infrared Window (11.45 µm) images [click to enlarge]

On the following night, toggles between VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images from Suomi NPP and NOAA-20 (below) showed a subtle signature of mesospheric airglow waves propagating northward away from the center of Cyclone Amphan.

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 (credit: William Straka, CIMSS) [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (credit: William Straka, CIMSS) [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images (credit: William Straka, CIMSS) [click to enlarge]

A View of the Development of Geostationary Imagers through the lens of BAMS

May 14th, 2020 |

A collection of 60 BAMS covers spanning the years, to highlight the rapid advance of imaging from the geostationary orbit, is shown above (a version that loops more slowly can be seen here). The first cover is the first of BAMS, in January of 1920, while the second, from January of 1957 is the first time artificial ‘satellite’ was in a title of a BAMS article. The third image, from November of 1957, is a remarkable article on potential uses of satellites. This included both qualitative uses: (1) Clouds, (2) Cloud Movements, (3) Drift of Atmospheric Pollutants, (4) State of the Surface of the Sea (or of Large Lakes), (5) Visibility or Atmospheric Transparency to Light — and quantitative uses: (1) Albedo, (2) Temperature  of  a  Level  at  or  Near  the Tropopause, (3) Total Moisture Content., (4) Total  Ozone  Content, (5) Surface  (Ground-Air Interface) Temperature, and (6) Snow Cover. Early covers showcase rockets, balloons and high-altitude aircraft to prepare the way to human space travel (Gemini, Apollo, etc.), polar-orbiters (TIROS, NIMBUS, VHRR, NOAA, etc.) and finally geostationary orbit (ATS-1, ATS-3, SMS, GOES, Meteosat, INSAT, Himawari, etc.).

Reasons to look back at the BAMS covers:

Interactive web page, with links to the original “front matter”.

Montage of select BAMS covers

Montage of select BAMS covers

Note: All cover images are from the Bulletin of the American Meteorological Society.