Aerosol plume moving offshore from the Northeast US

March 19th, 2010
GOES-12 0.65 µm visible images

GOES-12 0.65 µm visible images

McIDAS images of the GOES-12 0.65 µm visible channel data (above) revealed a large hazy aerosol plume that was moving off the Northeast US and drifting out over the adjacent waters of the Atlantic Ocean on 19 March 2010. This aerosol plume exhibited Aerosol Optical Depth (AOD) values of 0.6 and higher on the GOES Aerosol/Smoke Product (GASP) on the IDEA site. Real-time GASP images are also available from the NOAA/NESDIS/SSD/OSDPD site.

A MODIS true color Red/Green/Blue (RGB) image from the SSEC MODIS Direct Broadcast site (below) showed a better view of the varying structure and optical thickness of the aerosol plume.

MODIS true color Red/Green/Blue (RGB) image

MODIS true color Red/Green/Blue (RGB) image

An AWIPS image of the MODIS 0.65 µm visible channel data with an overlay of ECMWF 805-500 hPa layer winds (below) shows that the hazy aerosol plume was being advected eastward by a predominantly westerly flow within that layer.

MODIS 0.65 µm visible image + ECMWF 850-500 hPa layer winds

MODIS 0.65 µm visible image + ECMWF 850-500 hPa layer winds

Model output from the Realtime Air Quality Modeling System (RAQMS) shows the mixing ratio of surface sulfate or SO4 (below) — this demonstrates the increase in SO4 levels over the northeastern US during the 17-19 March period, with a forecast that then advects the high levels of SO4 eastward out over the Atlantic.

RAQMS surface sulfate (SO4) mixing ratio

RAQMS surface sulfate (SO4) mixing ratio

Clear Skies over the Great Lakes

March 19th, 2010

Saint Patrick’s Day over the Midwest was unusually clear, affording great images of the Great Lakes from the MODIS instrument aboard the Terra and Aqua satellites. The loop above includes the Visible imagery, the cirrus detection channel (1.38 micrometers), the snow-ice detection channel (2.1 micrometers), the derived lake-surface temperatures and the normalized difference vegetation index (NDVI).

Close-up views of the individual lake basins: Ontario, Erie, Michigan-Huron and Superior show mostly uniform surface temperatures in the upper 30s (Fahrenheit) as is normal in early Spring. There are warm thermal plumes in Lake Erie, however, emerging from Sandusky Bay and from the Maumee River at Toledo. MODIS-derived Lake surface temperatures in those regions are in the upper 40s. (True-color imagery for that time (here) show great turbidity over Lake Erie; perhaps the warm temperatures are a result of enhanced run-off from the Maumee and Sandusky Rivers) Temperatures over Lake Michigan are slightly warmer in the middle of the lake — near 40 F — than along the perimeter where lake temperatures are still in the mid-30s. This might be a signature of recently melted near-shore ice.

High-resolution imagery such as these will be routinely available when GOES-R is launched and becomes the operational GOES satellite over the United States.