Snow Field over Kansas2/22 – 2/24 2013

It is hard to tell exact dates of snow event. There is little snow seen on the AM pass for 2/20, then cloud cover until morning of 2/22.

The assumption is the snow fell between AM pass on 2/20 and the AM pass on 2/22.

Comparison for Day/Night passes on 2/22/2013

Night and Day passes for 2/22

Cloud Type Mask for 2/22 Purple = Clear; any other color = cloud

The cloud field for the Day passes looks reasonable. The Night case looks like it’s missing a lot, especially in the Northwest corner. I’m expecting some contamination.

Ranges for granule 0818:Scat angle: 94.0° -- 116.2°Zen angle: 58.75° –61.51°

Ranges for granule 1939Scat angle: 130.9° –137.6°Zen angle: 48.88° –51.87°

Ranges for granule 1941Scat angle: 130.9° –133.6°Zen angle: 50.94° –51.47°

Day and night peak at different reflectance values. However, peaks for day are very close, as is night peaks. Not sure if cloud contamination is effecting the night case.

Moon phase 40-49°

All day, and all night curves added together.

Both curves about same width, but Day peaks at a lower reflectance value than night curve. Not sure if this could be due to cloud contamination, or something else.

Comparison between 2/22 Day Passes and 2/23 Night Passes

Night passes for 2/23

Unfortunately, I was unable to use the image on the left– the IDL program tossed the values out as glint contaminated. I had to replace it with the two edge images on the right.

Cloud Type Mask for Night pass 2/23 Purple = Clear; any other color = cloud

Shows very little cloud contamination. Visual inspection of DNB image backs it up.

Comparison of Day 2/22 and Night 2/23 Passes, with clouds removed. Ranges for granule 1939

Scat angle: 130.9° –137.6°Zen angle: 48.88° –51.87°

Ranges for granule 1941Scat angle: 130.9° –133.6°Zen angle: 50.94° –51.47°

Ranges for granule 0939:Scat angle:157.5 ° – 159.3°Zen angle: 66.96° – 69.42°

Ranges for granule 0940:Scat angle: 158.8° – 159.80°Zen angle: 67.0° –68.52°

Only one night curve. Both day and the night curve peak at same point, but night much wider.

Moon phase 20-29°

All day, and all night curves added together.

Night curve much wider than Day curve, but both appear to peak around the same reflectance value. Not sure why, since range of both scatter and zenith angles are fairly narrow. Due to edge?

Comparison Between Day/Night passes on 2/23/2013

Day passes for 2/23

Cloud Type Mask for Day Pass 2/23 Purple = Clear; any other color = cloud

Only one main cloud in south of sector. Visual inspection of DNB image backs it up.

Ranges for granule 0939:Scat angle:157.5 ° – 159.3°Zen angle: 66.96° – 69.42°

Ranges for granule 0940:Scat angle: 158.8° – 159.80°Zen angle: 67.0° –68.52°

Ranges for granule 1921Scat angle: 117.2° –128.97°Zen angle: 47.81° –50.56°

Ranges for granule 1922Scat angle: 117.9° –128.2°Zen angle: 49.5° –50.57°

There is a lot of variation in the day curve due to large range in scat & zen angles. Total # of points much smaller for Scatter angles 120-129°

Moon phase 20-29°

Comparison of Day 2/23 and Night 2/23 Passes, with clouds removed.

Night phase much wider but seems to peak at approximately the same reflectance value as Day.

2/23 Day curve very similar to 2/22 Day curve, in spite of differences in scattering angle.

Comparison between 2/23 Day Passes and 2/24 Night Passes

Night pass for 2/24

Cloud Type Mask for Day Pass 2/24 Purple= Clear; any other color = cloud

Shows a lot of cloud. Not sure DNB image backs up clouds in center of sector, but possible.

Ranges for granule 0740Scat angle: 86.09 ° – 93.75°Zen angle: 38.97° – 42.45°

Ranges for granule 1921Scat angle: 117.2° –128.97°Zen angle: 47.81° –50.56°

Ranges for granule 1922Scat angle: 117.9° –128.2°Zen angle: 49.5° –50.57°

With so many variations of scattering and zenith angles, plot is very busy

Moon phase 20-29°

Comparison of Day 2/23 and Night 2/24 Passes, with clouds removed.

Night and Day curves similar in width, and just slightly off in peaks.

Overall Comments:

This case is not as clear cut as Colorado case.

KS curves tended to be wider than CO curves

The first day (2/22) actually had the Day/Night curve peaks more separated than the rest. Opposite in CO.