Power plant plumes in Minnesota

November 10th, 2008 |
MODIS + GOES-12 fog/stratus product images

MODIS + GOES-12 fog/stratus product images

AWIPS images of the 1-km resolution MODIS fog/stratus product and the 4-km resolution GOES-12 fog/stratus product (above) showed the value of the higher spatial resolution MODIS data for detecting subtle power plant plumes in the stratus clouds over northern Minnesota on 10 November 2008.  These plumes likely originated at large coal-fired power plants (or paper mills?) located across that region — emissions from these industrial sources may have acted as cloud condensation nuclei, causing a higher concentration of smaller supercooled cloud droplets downwind of the plants.

The MODIS Cloud Top Temperature values in the region were around -13º C (below, darker green color enhancement), and the MODIS Cloud Phase product indicated that the stratus clouds were composed of supercooled water droplets (blue color enhancement).

MODIS fog/stratus, IR, Cloud Top Temperature, and Cloud Phase images

MODIS fog/stratus, IR, Cloud Top Temperature, and Cloud Phase images

GOES-12 Low Cloud Base product indicated that the stratus clouds had bases below 1000 feet (below, green color enhancement), while the GOES-12 Cloud Top Height product suggested that the tops of the stratus clouds were around 13,000 feet (lighter green color enhancement).

MODIS fog/stratus, GOES low cloud base, GOES cloud top height products

MODIS fog/stratus, GOES low cloud base, GOES cloud top height products

It is interesting to note that similar power plant plumes were also seen on the MODIS fog/stratus product on the previous day (below), but without a stratus cloud deck over the region.

MODIS fog/stratus product images (09 and 10 November)

MODIS fog/stratus product images (09 and 10 November)