Eclipse 2015 in Wanstead

While heavy low cloud obscured the partial eclipse in this area there were a couple of interesting factors that I observed.

At 9.45am, shortly after the maximum obscuration of the solar disc the air pressure suddenly dropped. This coincided with sudden relief to my blocked nasal passages, symptoms of which appeared last night. Eighteen minutes later the fall in air pressure became less steep and the nasal symptoms returned.

The pressure dropped from 1029.8mb at 9.15am to 1029mb at 10.15am. I'm not sure if it was an effect of the eclipse or just a change in the synoptic situation that would have happened anyway
The pressure dropped from 1029.8mb at 9.15am to 1029mb at 10.15am. I’m not sure if it was an effect of the eclipse or just a change in the synoptic situation that would have happened anyway

As the light began to fade it seemed to turn colder though, on looking at the actual figures, the effect of the partial eclipse through heavy cloud was a depression in temperature of 0.3C. I worked this out by comparing today with yesterday which had almost identical weather conditions. People remarked that it turned noticeably colder though perhaps this was more caused by standing out in temperatures of 4.9C for a long period.

Like the eclipse in 1999 I noticed that the birdsong quietened somewhat though there was not the same crescendo of noise that you normally get at dusk when birds roost.

Here is the temperature trace from the 19th. Even with the heavy cloud yesterday there was more warming from the sun, albeit by a very small 0.3C
Here is the temperature trace from the 19th. Even with the heavy cloud yesterday there was more warming from the sun, albeit by a very small 0.3C
This graph shows the temperature from 6am until 11am. Though the depression during the eclipse was just 0.1C comparison with the previous day, which saw near identical weather conditions, shows just how much solar heating was depressed
This graph shows the temperature from 6am until 11am. Though the depression during the eclipse was just 0.1C comparison with the previous day, which saw near identical weather conditions, shows just how much solar heating was depressed
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