Sentinalhub Playground is an excellent resource for near real time, albeit not quite google earth 1m resolution, satellite images. One of the cool features is being able to adjust the mapping of the satellite bands to RGB outputs. For example, using Sentinel-2 L2A image data of South Lake Tahoe between 2021-08-17 and 2021-09-01 and remapping the 2190nm (SWIR2) to red, which tends to highlight fires though isn’t thermal, 783nm to green, a vegetation band (though it is NIR to humans) to make vegetation cover more obvious, and 443nm to blue instead of 490nm as shorter wavelengths tend to be scattered more by aerosols and smoke the fire line (bright red) and smoke (obvs) is very visible while vegetation is (false) green. Burnt earth shows as dark red, compared to bare ground, which tends to show tan in this mapping, thus revealing the current line of fire, the recently burned areas, and the wind direction carrying smoke, which tends to correlate with the advancing line, and fuel (vegetation) still standing.
Then using the history controller to generate and save a sequence of stills, we can animate the progress of the fire with a simple FFMPEG command:
ffmpeg -framerate 1 -pattern_type glob -i '*.jpg' -vf crop=1754:1146 -c:v libx264 -r 30 -pix_fmt yuv420p fire.mp4
and you get:
A few years back, when I was in 3rd or 4th Grade, my brother and I went to visit David and Jesse Lenat at their Cactus Farm. While we were exploring the green houses, their dad, Richard, gave us each a cactus to take home.
Mine lived in a small pot near the window through the rest of grade school and high school and then my mom cared for it through college. It grew into a little cluster of pencil thin green, spiky pads over the years.
After I graduated, moved to California, and got an apartment in SF; I was home for Christmas one year and took one of the pads wrapped in tissue to California. It grew well there and now produces big, bright yellow flowers every year.
This Christmas, I stuffed two tiny buds into glass bottles and brought them to Iraq and planted in the yard with one of the cat’s help (paw in the background).
Cool storm last night.
New experience today – 129+F Wikipedia says the highest temperature recorded in Basra was 52C. Now the car was driving over a sunlit road, so it was recording a higher temperature than you would see over shaded ground, but it is only May.
Summer is going to be fun.
Arriving in Italy we found our apartment had been squatted in by a swarm of hornets, probably through the chimney. It appeared they’d recently had a massive party and most, but not all had died.
We started a fire to clear the chimney and dispose of the corpses, which given how gigantic they were, was a lot of burning. By a lot, I mean dustpans full of hornets, some still crawling, at a time.
They could have been European Hornets, but the largest were closer to 5cm or so, fairly large even for European Hornets.