The annual eclipse this morning was quite a treat…even here in Seattle where only 80% of the sun’s disk was covered by the moon.
Viewable through a thin veil of clouds over Puget Sound country, the sun looked like a crescent moon around 9:10 AM (see a wonderful photo by my UW colleague Alex Anderson-Frey).
It was not a little eerie.
Solar radiation is measured on the top of the roof of my building and I plotted the solar radiation over time this morning (see plot below, time increases to the left). See below.
Solar radiation increased rapidly from 8 to 8:20 AM PDT (1500 to 1520 using a 24-h clock), then started to decline rapidly as the moon covered the sun!
Around 9:10-9:15 AM the solar radiation was at its weakest– a huge drop.
And then, as the moon moved off the sun, the solar radiation rapidly increased.
But if you really want to see how dramatic the loss of solar radiation was you need to check out a loop of the visible satellite imagery (see below). Look closely and you will see the shadow of the sun move through from west to east.
Finally, the loss of solar heating was obvious in the temperature plot of the UW (shown below). The temperature rose before 8:45 AM and then declined over the next hour, subsequently rebounding around 10 AM as full sun was restored.
In summary, a dramatic, interesting astronomical/meteorological event. And let me end with a superb image taken in the center of the eclipse in southern Oregon (by Deena Stevens)
