I think I’ve got data from both MODIS passes this afternoon. If I get more, I’ll add to the bottom of this post. No VIIRS data today, high res or not. Sorry.
The MODIS data is again good news for Cachagua residents. New fire activity is moving south, away from structures.
How to read the MODIS/VIIRS heat indications: The size of the square represents the nominal margin of error. The fire could be anywhere in the square, not just at the center. Dark red squares were detected less than six hours before the data set was created. Light red squares were detected less than twelve hours before the data set was created. Orange squares were detected less than 24 hours before the data set was created. Yellow squares were detected less than six days before the data set was created. When the squares overlay other objects, the color of the square changes somewhat, but the color of the dot in the middle does not. So look at the dot if you’re uncertain what color the square should be. Since the fire is now over six days old, some of the early detections have dropped off the map. MODIS makes mistakes, sometimes missing outbreaks, and sometime misplacing them outside the nominal margin of error. It is also a snapshot of the activity at the time the satellite is overhead, and will definitely miss flare ups between passes. MODIS can’t tell the difference between wildfires and intentional back burns.
The radiant power map is a bit hard to interpret:
Are those higher-intensity greenish blue squares yesterday’s hot spots or today’s? And why do they have magenta center dots?
We did get one more pass, and two new hot spots. The one near Cachagua is certainly a back burn:
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