On the weather

# South Lake Tahoe Caldor Fire Timelapse

Friday, September 3, 2021

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:

Posted at 08:17:00 GMT-0700

Category: EventsGeopostmaptechnologyvideoweather

# Summer Blooms

Friday, July 24, 2015

Posted at 13:41:13 GMT-0700

Category: photoweather

# Basra Snow Storm

Sunday, February 8, 2015

I was feeling a little left out, reading posts by people digging out of snow storms and here I am in Basra where it gets down to 10C at night sometimes and usually hits the mid 20’s during the day.  Rough.  But the weather here came through with our own sort of snow storm.

Starting to look like a brown-out!

Obligatory shot of the yard furniture getting covered.

Kitty’s head is starting to show some accumulation.

With all this blowing through you can barely see a few hundred meters!

It’s really starting to accumulate. Where’s the snow blower?

It takes some special cleaning after playing out in it.

Posted at 06:20:38 GMT-0700

Category: catsphotoplacestravelweather

# The Southern Iraqi Desert

Monday, February 4, 2013

The desert just north of Basra is beautifully empty.

(repost as only the old version of postie does the right thing with resizing images and creating proper thumbnails)
Click to enlarge.
Posted at 11:41:52 GMT-0700

Category: placestravelweather

# Lightning Strikes in Basra

Friday, May 11, 2012

Cool storm last night.

Posted at 10:48:22 GMT-0700

Category: Geopostphotoweather

# 54C

Friday, May 11, 2012

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.

Posted at 09:42:05 GMT-0700

Category: Geopostphototravelweather

# Central Park in the Snow

Friday, January 7, 2011

Snow falling on Central Park from the 24th floor.

Posted at 11:52:10 GMT-0700

Category: photoplacesweather

# Snowmaggeddon

Monday, December 27, 2010

a snowy arrival in BOS

But not exactly snowmaggeddon. By the time we got there it was easy to get around.

Posted at 14:16:39 GMT-0700

Category: photoplacestravelweather

# Rain, in LA? In May?

Tuesday, May 18, 2010

What next? Cats and dogs sleeping toghether?

Posted at 20:38:20 GMT-0700

Category: weather

Thursday, February 25, 2010

A little northern snow in the great white north.

Posted at 20:44:24 GMT-0700

Category: placestravelweather