Great Lake Water Surface Temperatures

June 13th, 2012 |
MODIS and AVHRR Lake Surface Temperatures (click image to play animation)

MODIS and AVHRR Lake Surface Temperatures (click image to play animation)

Clear skies over the upper Midwest on the morning of 13 June 2012 allowed the MODIS instrument on board Aqua and the AVHRR instrument on board NOAA-19 to sense the surface temperature of Lakes Michigan and Superior. Which instrument yielded observations that were closer to those recorded in situ by the moored buoys maintained by the National Data Buoy Center? The loop above of MODIS Lake Surface Temperatures and AVHRR Lake Surface Temperatures suggests that the MODIS-derived values are 1-3 Fahrenheit degrees warmer. MODIS values are also closer to the observed values at the moored buoys (45002 and 45007 in Lake Michigan, 45003 in Lake Huron and 45004 in Lake Superior). The higher spectral resolution on MODIS leads to a more accurate depiction of the lake surface in this case.

The National Weather Service in Sullivan, WI, has noted that lake temperatures are running much warmer than normal this year, in part because of the record warmth in March.

Large wildfire in Labrador, Canada

June 13th, 2012 |
GOES-13 0.63 µm visible channel images (click image to play animation)

GOES-13 0.63 µm visible channel images (click image to play animation)

McIDAS images of GOES-13 0.63 µm visible channel data (above; click image to play animation) revealed the development of a very broad and dense smoke plume emanating from a large wildfire that was burning just northwest of Goose Bay, Labrador (station identifier CYYR)  in far eastern Canada on 13 June 2012. Note the appearance of a number of bright “pyro-cumulus” clouds near the fire source region, as the very hot fires produced intense updrafts to form large towering cumulus clouds. As an aside, it is interesting to note that there were still a number of large ice floes (slow-moving brighter white features) not far off the Labrador coast, which were drifting slowly northward during the day.

McIDAS images of 375-meter resolution (projected onto a 1-km AWIPS grid) Suomi NPP VIIRS 0.64 µm visible channel data and 3.74 µm shortwave IR channel data (below) showed the large size of the fire “hot spot” (yellow to red to black pixels), in addition to the thick smoke plume.

Suomi NPP VIIRS 0.64 µm visible channel and 3.74 µm shortwave IR channel  images

Suomi NPP VIIRS 0.64 µm visible channel and 3.74 µm shortwave IR channel images

A comparison of Suomi NPP VIIRS 3.74 µm shortwave IR images from 12 June and 13 June (below) show how large the fire hot spot had grown in a day. Note that the surface air temperature at Goose Bay plotted on the 12 June image was 93 F (33.9 C) — the high temperature at Goose Bay on that day was actually 95 F (35 C), only 2.2 F (1.2 C) shy of their all-time record high temperature for the month of June.

Suomi NPP VIIRS 3.74 µm shortwave IR images (12 June and 13 June)

Suomi NPP VIIRS 3.74 µm shortwave IR images (12 June and 13 June)