Fires in Pacific Northwest

The Pacific Northwest (PNW), that is, the states of Washington, Oregon, Idaho and Western Montana are experiencing a significant heat wave right now. Air temperatures are scorching hot, with temperatures in the high 90’s and low 100’s. An amplified upper-level ridge has been quite persistent over the PNW, bringing the high temperatures and dry air to the area.

Due to the abnormally dry conditions, fires have been initiated and are scattered within the PNW. Fires can be seen below via two polar products: the Day/Night Band (DNB, 0.7um) and the Imagery Band 4 (I-4, 3.74um). The two products work in complement with one another. The DNB assists in utilizing a sun/moon reflectance model that illuminates atmospheric features, senses emitted lights, and assists with cloud monitoring during the nighttime, while the I-4 band senses the ‘fire hotspots’, areas that exude high brightness temperatures in comparison to the nearby environment. The I-4 band also assists the DNB in differentiating between what emitted lights are city lights, and what lights are the emitted lights from the fires.

It is important to note that the DNB and I-4 band are at two different spatial resolutions; DNB at 750 meters an the I-4 band at 375 meters. The static images can be seen below at 0924Z (0224 local time), 3 August 2017.

DNB

DNB_modified

I-4 Band

I4_modified