[ ] Figure out where to add this in the PgeRunconfig class
[ ] Grab the sample data for the delivery example
[ ] Update the description of this in the user guide
Reference date selection
[ ] Do a test over Alaska to determine if this tells us the correct time to pick as a reference date
Background
For each tile, seasonal composites of the coherence at different repeat intervals and backscatter imagery were calculated. We calculated the median coherence based on all coherence estimates per tile of a given repeat interval (6, 12, 18, 24, 36, and 48) per three-month period: 1) December, January, February 2) March, April, May 3) June, July, August, and 4) September, October, November. We chose the median operation to account for outliers. In the case of the backscatter intensity products, we calculated per three-month period the average backscatter intensity in VV and VH, or HH and HV, polarization.
The decay of coherence with increasing repeat interval was modelled for each season at pixel-level with the exponential model38
πΎπ‘(π‘)=(1βπβ)πβπ‘/π+πβ
(3)
where Οβ and Ο denote the long-term coherence and rate of coherence decay with increasing repeat interval, respectively.
Charlie has given a nice easy-to-use code example to pull the Josef global coherence dataset over an area of interest
https://github.com/OPERA-Cal-Val/s1-coherence-2020/blob/main/3_Seasonal_Coherence_View.ipynb
PgeRunconfigclassReference date selection
Background
The decay of coherence with increasing repeat interval was modelled for each season at pixel-level with the exponential model38 πΎπ‘(π‘)=(1βπβ)πβπ‘/π+πβ (3)
where Οβ and Ο denote the long-term coherence and rate of coherence decay with increasing repeat interval, respectively.