Wildfires in the Florida Panhandle

March 6th, 2022 |

GOES-16 Shortwave Infrared (3.9 µm, top left), Fire Temperature RGB (top right), Fire Temperature (bottom left) and Fire Power (bottom right) products [click to play animated GIF | MP4]

GOES-16 (GOES-East) Shortwave Infrared (3.9 µm), Fire Temperature RGB. Fire Temperature and Fire Power products (above) displayed signatures of the large Bertha Swamp Road Fire and a smaller Adkins Avenue Fire near Panama City in the Florida Panhandle on 06 March 2022. With the Bertha Swamp Road Fire, 3.9 µm Shortwave Infrared brightness temperatures reached 138.71ºC — the saturation temperature of ABI Band 7 detectors — the derived Fire Temperature maximum value was 2287.24 K, and Fire Power values peaked at 1440 MW. The Fire Temperature and Fire Power derived products are components of the GOES Fire Detection and Characterization Algorithm FDCA.

GOES-16 True Color RGB images created using Geo2Grid (below) showed smoke-laden pyrocumulus clouds (created by the very hot Bertha Swamp Road Fire), which rose above the level of boundary layer cumulus cloud streets that were moving inland across the area.

GOES-16 True Color RGB images [click to play animated GIF | MP4]

These fires were occurring in an area affected by the landfall of Hurricane Michael in 2018 — where a large amount of downed trees (within the shades of tan to light brown shown below on 18 October 2018) still remained. Both fires were located near the center of the MODIS images.

Terra MODIS True Color RGB images, before/after the landfall of Hurricane Michael [click to enlarge]

===== 07 March Update =====

GOES-16 Shortwave Infrared (3.9 µm, top left), Fire Temperature RGB (top right), Fire Temperature (bottom left) and Fire Power (bottom right) products [click to play animated GIF | MP4]

On 08 March, increasing surface wind speeds led to a consolidation of fires to form the Chipola Complex — and GOES-16 Shortwave Infrared, Fire Temperature RGB, Fire Temperature and Fire Power (above) indicated that this fire complex was centered in far southwestern Calhoun County, Florida.  Clouds often partially obscured a clear view of the entire fire, but the 3.9 µm Shortwave Infrared brightness temperatures reached 135.91ºC, the derived Fire Temperature maximum value was 1649 K, and Fire Power values peaked at 2121 MW.

GOES-16 True Color RGB images (below) again showed some pyrocumulus clouds near the fire source, with a larger smoke plume that extended well into southwestern Georgia. 

GOES-16 True Color RGB images [click to play animated GIF | MP4]

Rapid ice growth in Lake Erie

January 31st, 2022 |

GOES-16 “Red” Visible (0.64 µm) images, with surface wind barbs (knots) plotted in cyan [click to play animated GIF | MP4]

GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed the widespread coverage of ice across Lake Erie on 31 January 2022. Surface winds were generally light across the region, minimizing wind stress on the pack ice. A careful inspection of the imagery revealed some straight pathways cut through the ice by US Coast Guard icebreakers.

An Aqua MODIS True Color RGB image from the MODIS Today site (below) provided a higher-resolution view of the linear icebreaker paths in the western portion of the lake (where the ice was generally thicker).

Aqua MODIS True Color RGB image [click to enlarge]

The entire icebreaker channel was apparently completed sometime before sunrise on 31 January — the western portion was evident in a Sentinel-1A Synthetic Aperture Radar (SAR) Normalized Radar Cross Section (NRCS) image (source) at 2324 UTC on 30 January, and its eastward continuation was seen in a RCM-1 SAR NRCS image at 1136 UTC image on 31 January (below).

SAR NCRS images from Sentinel-1A at 2324 UTC on 30 January and from RCM-1 at 1136 UTC on 31 January [click to enlarge]

A toggle between GOES-16 Visible images at 1801 UTC on 29 January and 31 January (below) showed the marked increase in ice coverage during that 48-hour period.

GOES-16 “Red” Visible (0.64 µm) images at 1801 UTC on 29 January and 31 January 2022 [click to enlarge]

In fact, a GLERL plot of current Lake Erie ice coverage compared to the historical average (below) showed that the percentage of ice cover had recently become well above average for the date.

Plot of current Lake Erie ice coverage (black) compared to the historical average (red) [click to enlarge]

Quiz Time: What county in the USA has all boundaries visible from satellite?

December 2nd, 2021 |
MODIS-derived BRDF from 1 December 2021 (Click to enlarge)

MODIS-derived (from Terra and Aqua satellites) Bidirectional Reflectance Distribution Function (BRDF), above, (as noted in this blog post), shows the (meager) snow distribution as of early December. How many counties (or parishes) in the United States (out of more than 3000!) are clearly delineated in Satellite Imagery such as what is shown above? Counties that are primarily islands (or peninsulas) — Dare County in North Carolina, for example — show up well (False Color image shown here, in an image taken from VIIRS Today), but the inland borders do not.

For a county to be recognizable from Space, its landcover must differ significantly from adjacent counties. In the zooming-in animation below (from RealEarth, click the image to zoom in), users will note that Menominee County in northeast Wisconsin becomes apparent. Menominee County is almost entirely forest (unlike its neighbors) and as such has a much different signal in the (for example) 0.87 µm channel on VIIRS (or 0.86 µm on GOES-16). When it is zoomed in, the outlines of the County are obvious.

MODIS-derived BRDF from 1 December 2021 at various zoom levels (Click to animate)

The county also shows up well in the VIIRS True Color/False Color toggle below, from 30 November. The southern edge of the snow at that time was just southeast of Menominee County, and the land-use change across the county border is apparent. Snow in the county (cyan in the False Color enhancement) is difficult to view from the imagery — because of the pine forests!

VIIRS True-Color and False-Color imagery over northeastern WI, 1838 UTC on 30 November 2021 (Click to enlarge)

Menominee County has been on this blog before! In 2007, a tornado tracked through Menominee County and left a visible scar in satellite imagery (link). Eight years later (link), the scar was still apparent! November 6 2021 was a clear day over the upper Midwest. Suomi-NPP True Color imagery, below (link to original large image), still shows vestiges of the scar!

Suomi NPP True-Color imagery, 6 November 2021. The outline of Menominee County is apparent, as is the southwest-to-northeast tornado scar

Hole punch cloud features over Wisconsin and Illinois

November 22nd, 2021 |

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

GOES-16 (GOES-East) “Red” Visible (0.64 µm) and Near-Infrared “Snow/Ice” (1.61 µm) images (above) revealed the formation of several “hole punch” features across southeastern Wisconsin, northeastern Illinois and Lake Michigan on 22 November 2021 . These cloud features were caused by aircraft that were either ascending or descending through a relatively thin layer of clouds composed of supercooled water droplets — cooling from wake turbulence (reference) and/or particles from the jet engine exhaust acted as ice condensation nuclei, causing the small supercooled water droplets to turn into larger ice crystals (many of which then fall from the cloud layer, creating “fallstreak holes“). The ice crystal clouds appear as darker shades of gray on the 1.61 µm Snow/Ice images.

The GOES-16 Cloud Top Temperature derived product (below) showed that values were generally in the -30 to -35ºC range.

GOES-16 Cloud Top Temperature product [click to play animated GIF | MP4]

A toggle between 250-meter resolution Terra MODIS True Color and False Color RGB images from the MODIS Today site (below) provided a more detailed view of the numerous hole punch features at 1730 UTC, including a better depiction of the glaciated fallstreak clouds (shades of cyan) within the middle of each hole punch.

Terra MODIS True Color and False Color RGB images [click to enlarge]

Other blog posts showing examples of hole punch features can be found at this link.