July 13, 2010
Today's run started out very clear with hardly any clear. Haviland noted that the boundary layer looked interesting on the real-time returns on RunEarl.vi. At 1:26pm GMT at the beginning of the run, there was 89% humidity outside, and the visibility was 10.0 miles. Haviland wondered if variations in these over the day would be reflected in the data.
In real-time, there was no obvious object up at 13 kilometers. However, when ProcEarl was fed the data, cirrus clouds appeared at 13 kilometers. The cloud does not seem to be very thick nor very long, but from 1:40pm GMT until about 3:00pm GMT, there seem to be a consistently thin smattering of cirrus clouds, ranging from .5 to 1 kilometer thick, that were in the upper atmosphere at altitudes from 12 to 13 kilometers. These clouds showed up as having significant depolarization on the Depolarization Ratio graph, and therefore probably contain ice. This makes sense since clouds at heights above 7 kilometers generally exist in such cold temperatures that the water in the clouds freezes into ice molecules, which return a depolarized signal rather than a polarized signal.
In real-time, there was no obvious object up at 13 kilometers. However, when ProcEarl was fed the data, cirrus clouds appeared at 13 kilometers. The cloud does not seem to be very thick nor very long, but from 1:40pm GMT until about 3:00pm GMT, there seem to be a consistently thin smattering of cirrus clouds, ranging from .5 to 1 kilometer thick, that were in the upper atmosphere at altitudes from 12 to 13 kilometers. These clouds showed up as having significant depolarization on the Depolarization Ratio graph, and therefore probably contain ice. This makes sense since clouds at heights above 7 kilometers generally exist in such cold temperatures that the water in the clouds freezes into ice molecules, which return a depolarized signal rather than a polarized signal.
There were also some cirrus clouds that were about a kilometer thick between 6 and 8 kilometers. Because of the strong backscatter signal received from these lower clouds in comparison to the signal up at 13 kilometers, it is likely that the clouds at 6-8 kilometers were more dense and packed more water molecules than the higher altitude clouds. However, the depolarized signal represented on the Depolarization Ratio graph suggests that clouds at 6-8 kilometers also contained more water than ice. This happened yesterday, as well. The clouds at 8 kilometers yesterday had a significantly weaker depolarization signal than the higher clouds at altitudes of 10-12 kilometers. The warmer temperatures in the lower atmosphere as compared to the upper atmosphere, 6-8 kilometers as opposed to 13 kilometers, probably heats up the ice in the clouds more than the upper atmosphere, allowing more of the ice to melt into water. Or, in a different way of viewing, the cooler temperatures in the upper atmosphere at 13 kilometers freeze more water than the less cold temperatures at 8 kilometers.
There were even lower atmosphere clouds varying from about 750 meters to 2 kilometers. They lasted from about 3:00pm GMT until 5:00pm GMT, and then more appeared at about 6:10pm GMT and lasted until 7:30pm GMT. None of these clouds showed anything out of the ordinary.
There were even lower atmosphere clouds varying from about 750 meters to 2 kilometers. They lasted from about 3:00pm GMT until 5:00pm GMT, and then more appeared at about 6:10pm GMT and lasted until 7:30pm GMT. None of these clouds showed anything out of the ordinary.