Pyrocumulonimbus clouds in British Columbia, Canada

August 12th, 2017 |

GOES-16 Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images, with hourly surface reports plotted in yellow [click to play animation]

GOES-16 Visible (0.64 µm, top) and Shortwave Infrared (3.9 µm, bottom) images, with hourly surface reports 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) and Shortwave Infrared (3.9 µm) images (above) along with “Red” Visible and “Clean” Infrared Window (10.3 µm) images (below) showed the formation of 3 pyrocumulonimbus( pyroCb) clouds late in the evening on 12 August 2017, within the cluster of ongoing intense wildfires in British Columbia, Canada.

GOES-16 Visible (0.64 µm) and Infrared Window (10.3 µm) images, with hourly surface reports plotted in yellow [click to play animation]

GOES-16 Visible (0.64 µm, top) and Infrared Window (10.3 µm, bottom) images, with hourly surface reports plotted in yellow [click to play animation]

A toggle between NOAA-18 AVHRR Visible (0.63 µm), Near-Infrared (0.86 µm), Shortwave Infrared (3.9 µm) and Longwave Infrared Window (10.8 µm) images is shown below. The coldest cloud-top IR brightness temperature was -70º C (associated with the northernmost pyroCb).

NOAA-18 Visible (0.63 µm), Shortwave Infrared (3.9 µm) and Longwave Infrared Window (10.3 µm) images, with surface station plots in yellow [click to enlarge]

NOAA-18 Visible (0.63 µm), Shortwave Infrared (3.9 µm) and Longwave Infrared Window (10.3 µm) images, with surface station plots in yellow [click to enlarge]

In a daytime Suomi NPP VIIRS true-color Red/Green/Blue (RGB) image (from RealEarth) with VIIRS-detected fire locations plotted in red (below), a very large pall of exceptionally-dense smoke from the BC fires could be seen drifting northward as far as the Northwest Territories of Canada.

Suomi NPP VIIRS true-color image, with VIIRS-detected fire locations plotted in red [click to enlarge]

Suomi NPP VIIRS true-color image, with VIIRS-detected fire locations plotted in red [click to enlarge]

The Suomi NPP OMPS Aerosol Index (AI) product (below; courtesy of Colin Seftor, SSAI) displayed AI values as high as 17.18 within the thick BC fire smoke pall.

Suomi NPP OMPS Aerosol Index [click to enlarge]

Suomi NPP OMPS Aerosol Index [click to enlarge]

===== 13 August Update =====

Suomi NPP OMPS Aerosol Index product [click to enlarge]

Suomi NPP OMPS Aerosol Index product [click to enlarge]

On 13 August, a maximum OMPS AI value of 39.91 was seen at around 21:13 UTC over the Northwest Territories of Canada (above) — according to Colin Seftor and Mike Fromm (NRL), this value surpassed the highest pyroCb-related AI value ever measured by TOMS or OMI (whose period of record began in 1979).

The north-northeastward transport of BC fire smoke — as well as a prominent increase in smoke from fires across northern Canada and the Prairies — was evident in an animation of daily composites of Suomi NPP VIIRS true-color images from 07-13 August (below).

Daily Suomi NPP VIIRS true-color image composites (07-13 August), with VIIRS-detected fire locations plotted in red [click to play animation]

Daily Suomi NPP VIIRS true-color image composites (07-13 August), with VIIRS-detected fire locations plotted in red [click to play animation]

Wildfire burning in Greenland

August 4th, 2017 |
GOES-16 Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images [click to play animation]

GOES-16 Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images [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) and Shortwave Infrared (3.9 µm) images (above; a zoomed-in version is available here) displayed a subtle hazy signature of a smoke plume along with an intermittent “hot spot” (darker black pixels) associated with  a small fire — located near the center of the cyan circle — that was burning close to the southwest coast of Greenland on 01 August 2017. The approximate latitude/longitude coordinates of the fire were 67.87º N / 51.48º W, a location about halfway between Ilulissat (station identifier BGJN) and Kangerlussuaq (station identifier BGSF) and about halfway between the western edge of the Greenland Ice Sheet and the west coast .

Closer views using daily composites of 250-meter resolution Terra and Aqua MODIS true-color Red/Green/Blue (RGB) images (from 30 July to 04 August), sourced from RealEarth (below) indicated that the fire may have started close to 1540 UTC on 31 July — when a small white smoke and/or cloud feature (just north of the cursor) was seen at the fire source location on the Terra image (overpass time). The Aqua overpass time was around 1600 UTC.

Daily composites of Terra MODIS true-color RGB images, from 30 July to 04 August [click to enlarge]

Daily composites of Terra MODIS true-color RGB images, from 30 July to 04 August [click to enlarge]

Daily composites of Aqua MODIS true-color RGB images, from 30 July to 04 August [click to enlarge]

Daily composites of Aqua MODIS true-color RGB images, from 30 July to 04 August [click to enlarge]

Similar daily composite RGB images from Suomi NPP VIIRS (31 July to 04 August) are shown below. Note that the initial fire signature was not seen on the 31 May VIIRS image, due to the earlier overpass time  (1513 UTC) of the Suomi NPP satellite.

Daily composites Suomi NPP VIIRS true-color RGB images,.from 31 July to 04 August [click to enlarge]

Daily composites of Suomi NPP VIIRS true-color RGB images,.from 31 July to 04 August [click to enlarge]

On 03 August, a 1507 UTC overpass of the Landsat-8 satellite provided a 30-meter resolution Operational Land Imager (OLI) false-color RGB image of the fire (below). This was the same day that a pilot took photos of the fire, as reported on the Wildfire Today site.

Landsat-8 false-color RGB image [click to enlarge]

Landsat-8 OLI false-color RGB image [click to enlarge]

A comparison of one “before” (27 July) and two “after” (03 and 05 August) Landsat-8 OLI false-color RGB images (below) showed differences in smoke plume transport as the wind direction changed.

Landsat-8 false-color images on 27 July, 03 August and 05 August [click to enlarge]

Landsat-8 OLI false-color images on 27 July, 03 August and 05 August [click to enlarge]

It is possible that this “natural fire” is similar to the Smoking Hills type of spontaneous combustion that has been observed in the Canadian Arctic (thanks to Ray Hoff, retired UMBC Professor of Physics, for that tip).

Credit to Mark Ruminski (NOAA/NESDIS) for first bringing this interesting event to our attention.

===== 09 August Update =====

The animations of daily Terra and Aqua true-color RGB images (below) have been extended to 09 August and 08 August, respectively.

Daily composites of Terra MODIS true-color RGB images, from 30 July to 09 August [click to enlarge]

Daily composites of Terra MODIS true-color RGB images, from 30 July to 09 August [click to enlarge]

Daily composites of Aqua MODIS true-color RGB images, from 30 July to 08 August [click to enlarge]

Daily composites of Aqua MODIS true-color RGB images, from 30 July to 08 August [click to enlarge]

Suomi NPP VIIRS true-color RGB images from 04-09 August (below) include VIIRS-detected fire locations plotted in red. The 09 August image showed that smoke from the fire had drifted west-southwestward over the adjacent offshore waters of Davis Strait.

Daily composites of Suomi NPP VIIRS true-color RGB images, from 04-09 August, with fire detection points plotted in red [click to enlarge]

Daily composites of Suomi NPP VIIRS true-color RGB images, from 04-09 August, with fire detection points plotted in red [click to enlarge]

Related sites:

NASA Earth Observatory

NPR

ESA Space in Images

 

Hail damage swath in South Dakota and Minnesota

July 4th, 2017 |

SPC storm report plots, from 12 UTC on 21 June to 12 UTC on 22 June 2017 [click to go to SPC storm reports list]

SPC storm report plots, from 12 UTC on 21 June to 12 UTC on 22 June 2017 [click to go to SPC storm reports list]

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

As seen on the map of SPC storm reports from 21 June 2017 (above), nighttime thunderstorms (during the pre-dawn hours of 22 June) produced a swath of hail (as large as 2.0 inches in diameter) that damaged emerging crops at some locations across eastern South Dakota and southwestern Minnesota (NWS Aberdeen summary).

Nearly 2 weeks later, on 04 July, the hail damage swath was still apparent on GOES-16 imagery. In a comparison of “Blue” Visible (0.47 µm), “Red” Visible (0.64 µm) and Near-Infrared “Vegetation” (0.86 µm ) images (below), the northwest-to-southeast oriented hail damage swath was best seen on the 0.64 µm imagery (in part due to its higher spatial resolution, which is 0.5 km at satellite sub-point); healthy vegetation is more reflective at 0.86 µm, so the crop-damaged hail swath appears slightly darker in those images.

GOES-16

GOES-16 “Blue” Visible (0.47 µm, top), “Red” Visible (0.64 µm, middle) and Near-Infrared “Vegetation” (0.86 µm, bottom) images [click to play animation]

A signature of the hail damage swath was also seen in Near-Infrared “Snow/Ice” (1.61 µm) and Shortwave Infrared (3.9 µm) images (below). The hail damage swath warmed more quickly on the 3.9 µm imagery — exhibiting a darker black appearance with time — compared to the adjacent fields of healthy crops.

GOES-16

GOES-16 “Red” Visible (0.64 µm, top), Snow/Ice (1.61 µm, middle) and Shortwave Infrared (3.9 µm, bottom) images [click to play animation]

Why was the hail damage swath also seen on the 1.61 µm “Snow/Ice” (Band 5) imagery? A look at the Spectral Response Functions for GOES-16 ABI  bands 3, 4, 5 and 6 — plotted with the reflectance of asphalt, dirt, grass and snow (below) — show that the 1.61 µm Band 5 happens to cover a portion of the radiation spectrum where there is a minor peak in grass relectance (denoted by the green plot).

Spectral Response Functions for GOES-16 ABI Bands 3, 4, 5 and 6, along with the reflectance of asphalt, dirt, grass and snow [click to enlarge]

Spectral Response Functions for GOES-16 ABI Bands 3, 4, 5 and 6, along with the reflectance of asphalt, dirt, grass and snow [click to enlarge]

======================================================

Aqua MODIS Land Surface Temperature product {click to enlarge]

Aqua MODIS Land Surface Temperature product {click to enlarge]

Regarding the warmer temperatures seen on GOES-16 Shortwave Infrared images, the 1-km resolution Aqua MODIS Land Surface Temperature product at 1738 UTC (above) revealed a 10º F difference between the warmer hail damage swath (which appeared to be about 100 miles in length) and adjacent fields of undamaged crops. A similar result was noted on 03 July by NWS Aberdeen (below).

A comparison of before (21 June) and after (02 July) Aqua MODIS true-color Red/Green/Blue (RGB) images from the SSEC MODIS Direct Broadcast site (below) clearly shows the hail damage path.

Aqua MODIS true-color RGB images, before (21 June) and after (02 July) the hail event [click to enlarge]

Aqua MODIS true-color RGB images, before (21 June) and after (02 July) the hail event [click to enlarge]

On 05 July a closer view of the hail scar was seen using a Suomi NPP VIIRS true-color RGB image from RealEarth (below).

Suomi NPP VIIRS true-color RGB image [click to enlarge]

Suomi NPP VIIRS true-color RGB image [click to enlarge]

Incidentally, on 02 July the Sentinel-2A satellite provided 10-meter resolution true-color imagery of the hail swath:

===== 07 July Update =====

The hail damage swath was also evident on a 30-meter resolution Landsat-8 false-color RGB image from 07 July:

Landsat-8 false-color RGB image [click to enlarge]

Landsat-8 false-color RGB image [click to enlarge]

Landsat-8 false-color RGB image, zoomed in on Castlewood, South Dakota [click to enlarge]

Landsat-8 false-color RGB image, zoomed in on Castlewood, South Dakota [click to enlarge]

Other examples of satellite-observed hail damage swaths can be seen here and here.

 

Rain/hail swath in Nebraska and Kansas

June 26th, 2017 |

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

As indicated in the Tweet above from NWS Hastings, GOES-16 imagery highlighted the presence of a narrow swath of rainfall and hail in the wake of a small thunderstorm that moved south/southeastward across the Nebraska/Kansas state line area on 26 June 2017.

A 3-panel comparison of GOES-16 Visible (0.64 µm), Snow/Ice (1.61  µm) and Shortwave Infrared (3.9  µm) images (below) revealed a subtle signature of the hail swath on the Snow/Ice images (where ice features appear as darker shades of gray: southern NE  | northern KS), while the Shortwave Infrared images showed that the hail and rainfall swathaccumulations in southern Kansas included 0.58″ at Clay Center and 0.49″ at Hebron — remained slightly cooler (lighter gray) as the adjacent dry land surfaces continued to warm during the early to middle afternoon hours. SPC storm reports listed hail of 1.75 inches in diameter in southern Nebraska and 1.25 inches in northern Kansas.

GOES-16 Visible (0.64 µm, left), Snow/Ice (1.61 µm, center) and Shortwave Infrared (3.9 µm, right) images, with hourly surface reports plotted in yellow and SPC storm reports of hail size plotted in red [click to play MP4 animation]

GOES-16 Visible (0.64 µm, left), Snow/Ice (1.61 µm, center) and Shortwave Infrared (3.9 µm, right) images, with hourly surface reports plotted in yellow and SPC storm reports of hail size plotted in red [click to play MP4 animation]

Regarding the cooling seen associated with the rainfall/hail swath, a Land Surface Temperature (LST) product derived using Aqua MODIS data (below) indicated that LST values were generally in the upper 60s to upper 70s F within the narrow swath,  in contrast to LST values in the 90s to around 100º F adjacent to the swath.

Aqua MODIS Land Surface Temperature product, Visible (0.65 µm), Infrared Window (11.0 µm) and Shortwave Infrared (3.7 µm) images [click to enlarge]

Aqua MODIS Land Surface Temperature product, Visible (0.65 µm), Infrared Window (11.0 µm) and Shortwave Infrared (3.7 µm) images [click to enlarge]