ISMN quality flags
WE DO NOT ERASE DATA - WE FLAG (see Dorigo et. al 2013 or https://ismn.earth/en/data/flag-overview/).
ISMN quality flags are tags stored in our database with each observation. When the ISMN automated quality control detects a dubious soil moisture (or other variable) observation it is marked as "C01-C03" or "D01-D10", which signify different flagging methods. See below for example content of a data-file downloaded from ISMN.
date |
value |
quality flag |
origflag (Provider) |
| 2017/04/19 00:00 | 0.2420 | D03 | M |
| 2017/04/19 01:00 | 0.2450 | D03 | M |
| 2017/04/19 02:00 | 0.4070 | D03,D10 | M |
| 2017/04/19 03:00 | 0.4070 | D03,D10 | M |
| 2017/04/19 04:00 | 0.4070 | D03,D10 | M |
| 2017/04/19 05:00 | 0.4070 | D03,D10 | M |
| 2017/04/19 06:00 | 0.3040 | G | M |
Flag methodology
For a detailed description of the methodology behind the quality flags we refer to:
Dorigo, W.A. , Xaver, A. Vreugdenhil, M. Gruber, A., Hegyiová, A. Sanchis-Dufau, A.D., Zamojski, D. , Cordes, C., Wagner, W., and Drusch, M. (2013). Global Automated Quality Control of In Situ Soil Moisture data from the International Soil Moisture Network. Vadose Zone Journal, 12, 3, doi:10.2136/vzj2012.0097
Dorigo, W., I. Himmelbauer, D. Aberer, L. Schremmer, I. Petrakovic, L. Zappa, W. Preimesberger, A. Xaver, and 54 Co-Authors (2021). The International Soil Moisture Network: serving Earth system science for over a decade Hydrol. Earth Syst. Sci. Discuss., preprint/in review, 2021, doi:10.5194/hess-2021-2