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Why Was Yesterday's Sunlight Brighter Than This Morning?

  1. Jul 14, 2016 #1
    Yesterday morning the lighting from the sunlight made everything brighter until 11:50am Pacific Daylight time. I am in the San Francisco Bay Area in Northern California. Can you explain why sunlight on 13 July 2016 appears to be 'brighter' than this morning?
  2. jcsd
  3. Jul 14, 2016 #2


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    This is vague. Did you actually measure this brightness, or are you just relying on what you see with your eyes? The latter is not terribly reliable, because it depends many circumstances (i.e. did you just walk out of a darker area when you went outside?).

  4. Jul 14, 2016 #3
    I was looking out the window this morning and noticed how the brightness was not the same compared to yesterday. Yesterday morning I was looking out the window from the same room. I did not use a light meter to measure the lighting.
  5. Jul 14, 2016 #4
    The color temperature changed around 11:00 am - 11:50 am Pacific Daylight Time. I noticed the color temperature or hue changed around 11:50am PDT. I should have written the time.
  6. Jul 14, 2016 #5


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    If there was a real difference and not just your eye's unreliable perception, it could probably be described by the varying amounts of aerosols in the atmosphere smog, fog, etc etc

    relying just on your eyes like that would be very unreliable
  7. Jul 14, 2016 #6


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    According to weatherunderground.com, at 11 this morning it was partly cloudy and 11 yesterday morning it was clear.
  8. Jul 14, 2016 #7
    I will use the Desktop Spectrometry Kit 3.0 from Public Lab. This spectrometry kit may not be sensitive enough.
  9. Jul 20, 2016 #8
    Well, interesting
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