Solar Radiation Measurements and Object Scattering

The Color of Skin

• Color of skin doesn’t effect the way each wavelength reflects

• Only the amount of radiation differs in different skin colors

• Caucasians like Stephen have skin that reflects more radiation than darker races like Tian and Narayan

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Narayanfacem Stephenfacem Tianfacem Stepheneyem

Objects with Colors

• The yellow can and blue book reflect with more radiation than the others

• The book is centered around the blue and the can has its max near yellow.

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bluebookcoverm bushm hollyleafm lilym redcoffecupm yellowcanm

Organic Plant Material

• The holly and the bush have similar spectrums but the holly has weaker radiation than the bush

• The lily flower has a strong maximum in the red and then a weaker one in the blue it also has a similar structure in the near infrared as the holly leaf

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bushm hollyleafm lilym

Differences in Red• Both reflect strongly

near 640 nm which denotes the reddish color

• The flower has a second maximum near the 450 nm band which would mean there is also more of a blue color explaining the pinkish hue

• The red coffee cup appears to have less reflected radiation but has close to only one maximum which makes it more red than the lily flower.

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lilym redcoffecupm

Morning Solar spectrum• At 7:48 am the spectrum

was similar to that of the 8:19 am but at 8:16 am it was stronger

• From 8:30 and on there was a weaker solar spectrum

• These changes are from the differing amounts of cloud cover that existed

• The more clouds there were the more the light was scattered to our eyes/instruments

• At 748 however it was cloudy but the clouds were thicker and the radiation was getting slightly more attenuated in the cloud

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0748m 0816m 0819m 0830m 0840m 0852m

Morning Spectrum

9:05 Increase in Solar Spectrum• At 9:00 am to 9:05

am the solar spectrum increased but by 9:10 am it began to decrease towards the point it was at 8:52 am

• On the next slide the visible reason is that the sun is to the east and the clouds above reflect/scatter the light towards our eyes/instruments

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0852m 0900m 0905m 0910m 0930m 0940m

9:05 Increase in Solar Spectrum

Midday Cirrus Clouds• 12:28 pm is stronger

than 12:08 pm before it but as well as 13:08 pm after it

• The cirrus clouds that were around due to the contrails from airplanes caused the change

• One contrail crossed overhead and scattered the radiation towards our instruments

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1208m 1215m 1228m 1252m 1305m

Midday Cirrus Clouds