Swan Lake Fire in Alaska

August 17th, 2019 |

GOES-17

GOES-17 “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm) and Shortwave Infrared (3.9 µm) images (above) revealed thick smoke and a pronounced thermal anomaly (hot pixels, darker black) associated with the Swan Lake Fire on the Kenai Peninsula in south-central Alaska on 17 August 2019. Later in the day, a few pyrocumulus jumps could be seen in Visible imagery over the fire source region, as fire behavior increased (another day when pyrocumulus jumps were apparent with this fire was 30 June, during a period when southerly winds were transporting dense smoke to the Anchorage area).

Strong northerly-northwesterly winds were transporting smoke from the Swan Lake Fire southward across the Kenai Peninsula and the Seward area — a time series of surface report data from Seward (below) showed that this smoke had reduced the visibility to less than 1 mile by 03 UTC (7 PM local time). South-central Alaska was experiencing drought conditions, which had worsened from the preceding week; the strong winds on this day acted to dry fuels even further, leading to a re-invigoration of the long-lived fire.

Time series of surface reports from Seward, Alaska [click to enlarge]

Time series of surface report data from Seward, Alaska [click to enlarge]

Seward Airport webcam image at 2358 UTC [click to enlarge]

Seward Airport webcam image at 2358 UTC [click to enlarge]

The PM2.5 Air Quality Index reached 427 at Cooper Landing, and 358 farther downwind at Seward (below).

Air Quality Index at Copper Landing and Seward [click to enlarge]

Air Quality Index at Copper Landing and Seward [click to enlarge]

The southward transport of smoke across the Seward area and out over the adjacent offshore waters of the Gulf of Alaska was evident in VIIRS True Color Red-Green-Blue (RGB) images from NOAA-20 and Suomi NPP, as viewed using RealEarth (below).

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

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

Milepost 97 Fire in southwestern Oregon

July 26th, 2019 |

GOES-17 Fire Temperature RGB,

GOES-17 Fire Temperature RGB, “Red” Visible (0.64 µm), CIMSS Natural Color RGB and Day Cloud Phase Distinction RGB images [click to play animation | MP4]

An animation that cycles through GOES-17 (GOES-West) Fire Temperature Red-Green-Blue (RGB), “Red” Visible (0.64 µm), CIMSS Natural Color RGB and Day Cloud Phase Distinction RGB images (above) showed the thermal anomaly (darker red pixels) and smoke associated with the Milepost 97 Fire in southwestern Oregon on 26 July 2019. In this particular case, dense smoke appeared as darker shades of green in the Day Cloud Phase Distinction RGB images.

A time series of surface data from Sexton Summit (immediately downwind of the fire) indicated that smoke reduced the surface visibility at that location to 1/4 mile at times; farther from the fire, the visibility was in the 2-3 mile range at times in Medford (below).

Time series of surface data from Sexton Summit [click to enlarge]

Time series of surface data from Sexton Summit [click to enlarge]

Time series of surface data from Rogue Valley International Airport in Medford [click to enlarge]

Time series of surface data from Rogue Valley International Airport in Medford [click to enlarge]

===== 27 July Update =====

GOES-17 True Color RGB images [click to play animation | MP4]

GOES-17 True Color RGB images [click to play animation | MP4]

GOES-17 True Color RGB images from the AOS site (above) showed the increased coverage of smoke from the Milepost 97 Fire, spreading across southern Oregon and into Northern California on 27 July. Some of the smoke had been lofted to higher altitudes, being transported as far northeastward as Montana.

Later in the day, GOES-17 True Color RGB images showed that the smoke had moved a significant distance southward along and just off the California coast (below).

GOES-17 True Color RGB images [click to play animation | MP4]

GOES-17 True Color RGB images [click to play animation | MP4]

Elevated NO2 signatures over the Northeast US

July 19th, 2019 |

TROPOMI NO2 concentration [click to enlarge]

TROPOMI NO2 concentration, courtesy of Bob Carp, SSEC [click to enlarge]

High temperatures (along with high dewpoints) prompted the issuance of Excessive Heat Warnings across much of the Northeast US on 19 July 2019. Under such conditions, surface NO2 concentrations in densely-populated urban areas often become elevated (primarily driven by emissions from motor vehicle exhaust, along with secondary sources such as coal-fired power plants and manufacturing / food processing industrial sources) — the high temperatures accelerate chemical reactions that form pollutants. The TROPOMI instrument detected plumes of elevated NO2 extending downwind (to the northeast) of major cities such as Philadelphia, New York City and Boston (above). The data are displayed using McIDAS-V.

A closer view centered on New York City is shown below.

TROPOMI NO2 concentration [click to enlarge]

TROPOMI NO2 concentration, courtesy of Bob Carp, SSEC [click to enlarge]

The Aqua MODIS Land Surface Temperature product around that time (below) revealed LST values in the 100-110ºF range across the New York City and Boston areas, where the daily maximum surface air temperatures were 95ºF and 93ªF, respectively.

Aqua MODIS Land Surface Temperature, with plots of daily maximum surface air temperatures [click to enlarge]

Aqua MODIS Land Surface Temperature, with plots of daily maximum surface air temperatures [click to enlarge]

Jet skier stranded by fog in Lake Superior

July 8th, 2019 |

GOES-16

GOES-16 “Red” Visible (0.64 µm) images [click to play animation | MP4]

GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed narrow ribbons of fog over the northwestern portion of Lake Superior on 08 July 2019. A person attempting to navigate from Grand Portage, Minnesota — located northeast of Grand Marais Airport, identifier KCKC — to Isle Royale became lost in the fog and eventually ran out of fuel (media story).

Possibly compounding the fog-related visibility problem, GOES-16 Natural Color Red-Green-Blue (RGB) images (below) revealed that dense smoke from Canadian wildfires was lingering and also recirculating slowly northward across Lake Superior; this smoke occasionally reduced the surface visibility to 4 miles at Houghton, Michigan (identifier KCMX).

GOES-16 Natural Color RGB images [click to play animation | MP4]

GOES-16 Natural Color RGB images [click to play animation | MP4]