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Differential phase. Experience to date on the Bolton link. Some definitions. Differential phase is the difference in phase between the horizontally and vertically polarised components of the electric field. We are measuring the total (one-way) differential phase along the path.
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Differential phase Experience to date on the Bolton link
Some definitions • Differential phase is the difference in phase between the horizontally and vertically polarised components of the electric field. • We are measuring the total (one-way) differential phase along the path. • The Thurnham radar measures the aggregate of the two-way differential phase to, and the differential backscatter phase from, the radar volume being sensed
Hameldon Hill to Clarke’s Hill • Distance is 23.2km • There follows a sample set of link traces and rainfall comparisons illustrating variety of data collected
And now some rain events All temperature plots come from Edgworth Wunderground website
01Dec 2005; other data T E M P G A U G E S
Possible explanation • Very small drops? • If the drops were almost spherical, there would still be attenuation, but no differential phase of note
In the next slide, look at what happens to the phase at the end of the peak at 12noon • Notice also at the same moment what happens to the two attenuations • The following slide shows all gauges near the link with rain around 12noon
TEMP G A U G E S
Some comments • Differential phase seems to do much better than I would expect in the rain (it is not linear with rainrate) • Its behaviour in sleet looks to be variable • It may have identified snow • It seems to be quite dependent on the atmospheric conditions