GEUS-Glaciology-and-Climate / pypromice

Process AWS data from L0 (raw logger) through Lx (end user)
https://pypromice.readthedocs.io
GNU General Public License v2.0
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Latest coordinates shifted by 200m at DY2 compared to station location #152

Closed BaptisteVandecrux closed 10 months ago

BaptisteVandecrux commented 1 year ago

red dots are monthly averaged transmitted positions image

BaptisteVandecrux commented 1 year ago

During the bufr processing, a linear regression is fitted to the available transmitted coordinates. Unfortunately, this regression and the OLS minimization is to sensitive to outliers. E.g. these outliers: image

... lead to this linear regression: image

Switching to a RANSAC regressor leads to more robust estimation: image

More testing on the way before I make this update.

BaptisteVandecrux commented 1 year ago

Examples where RANSAC don't work: image

image

image

another problem at KAN_M where only coordinates from SBD messages are available: image

For the moment I am switching off the gap-filling with SBD coordinates and using SBD average when no coordinates are available.

BaptisteVandecrux commented 10 months ago

This is now fixed: billede