We’ve got results from the first MODIS pass of this afternoon:
[High-res VIIRS data is in this post too, down towards the bottom.]
Here’s what I think we’re looking at. Look for the red circles:
I make those identifications not through any knowledge of today’s fire operations, but just because of their locations. If you think I’m wrong )which is entirely possible), please let me know.
[Added 1600] Here are the results of the second pass:
Not much different; the passes were less than two hours apart. If we are to believe the latest southern hotspot, the two arms of the fire that are moving southward in kind of a pincer movement are likely to join.
The VIIRS pass took place at 2:30 this afternoon, but I don’t have the data set yet.
[1700. Now I’ve got the high-res VIIRS data]
Here’s a big look at it:
And some details, with arrows (no circles, thought, all you Arlo Guthrie fans) and comments.
The orange lines are the dozer fire breaks that were in as of 7/30, plus one that I added by hand. The pink lines are the ones that were planned as of that date.
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.
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