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--- clipc:start [2015-07-14 13:06:09] – andreasd
+++ clipc:start [2016-11-03 13:19:38] (current) – [Description of the Met Norway method] andreasd
@@ Line 2: / Line 2: @@
 ===== Available bias-corrected data =====
-  * Bias-corrected EUR-44 CORDEX and EUR-11 CORDEX RCM data from Met Norway are available at [[http://arcticdata.met.no/metamod/search/page/1/result?active_criteria=&freetext_13=clipc|the Arctic Data Centre]] ([[http://thredds.met.no/thredds/catalog/arcticdata/met.no/CLIPC/catalog.html| Thredds catalog]])
+Bias-corrected EUR-44 CORDEX and EUR-11 CORDEX RCM data made by SMHI, IPSL and Met Norway for CLIPC are now **available** (with others) through the [[https://esgf-data.dkrz.de/search/esgf-dkrz/|ESGF]] project "CORDEX-Adjust".
-  * Bias-corrected EUR-44 CORDEX and EUR-11 CORDEX RCM data from SMHI are available [[http://exporter.nsc.liu.se/b780c1ede6904458829bae06bb99779d|here]]
+More information can be found [[http://www.cordex.org/index.php?option=com_content&view=article&id=275&Itemid=785|here]].
-  /* * Bias-corrected EUR-11 CORDEX from IPSL are available [[http://cse.ipsl.fr/donnees/128-bc-cordex-data|here]] */
-NOTE that this are **PRELIMINARY DATA PUBLICATIONS**. Data formats, availability and content MAY CHANGE without notice.\\
 PLEASE REPORT to [[andreas.dobler@met.no|Andreas Dobler]], if you find something strange or errors in the Met Norway data.
-Currently, the bias-corrected datasets are linked in this place and also on the [[http://www.clipc.eu/the-project/public-deliverables-and-milestones/milestones#m25|CLIPC milestone page]]. They will eventually become available through [[http://esgf.llnl.gov/|ESGF]].
 Please have a look at some [[evaluation]] plots considering the bias-corrected data from Met Norway.
+An overview on the bias-corrected data from Met Norway can be found here {{:clipc:BiasCorrectedDataList.pdf|}}
 ===== Project and deliverable summary =====
@@ Line 21: / Line 19: @@
   - Bias-corrected global climate model (GCM) data interpolated to a common 2° × 2° grid,
-The Meteorologisk institutt provides bias-corrected data at the EURO-CORDEX 0.11° and the EURO-CORDEX 0.44° grid. The latter will also contribute to the Bias Correction Intercomparison Project [[http://www.meteo.unican.es/en/node/73279|BCIP]].
+The Meteorologisk institutt provides bias-corrected data at the EURO-CORDEX 0.11° and the EURO-CORDEX 0.44° grid. These will also contribute to the Bias Correction Intercomparison Project [[http://www.meteo.unican.es/en/node/73279|BCIP]].
 ===== Terms of use=====
-All EURO-CORDEX simulations are published under the [[http://cordex.dmi.dk/joomla/images/CORDEX/cordex_terms_of_use.pdf|CORDEX terms of use]]. Until further notice, the terms of use for the bias-corrected data are the same as those from the uncorrected EURO-CORDEX simulations obtained from ESGF servers. If you are not sure what the terms for a specific simulation are, consider the data as restricted for non-commercial research and educational purposes only. An overview on the restriction will follow as soon as the ESGF servers are online again.
+All EURO-CORDEX simulations are published under the [[http://cordex.dmi.dk/joomla/images/CORDEX/cordex_terms_of_use.pdf|CORDEX terms of use]]. Until further notice, the terms of use for the bias-corrected data from CLIPC are the same as those from the uncorrected EURO-CORDEX simulations obtained from ESGF servers. These are:
+  * All simulations have non-restricted use
 We acknowledge the following grants and work. Please acknowledge/cite these when you use or redistribute the bias-corrected CLIPC data from Met Norway.
   * The CLIPC EU project (grant agreement #607418)
   * The EURO4M FP7 project (grant agreement #242093) and Hāggmark, L., Ivarsson, K.-I., Gollvik, S. and Olofsson, P.-O., 2000: MESAN, an operational mesoscale analysis system. Tellus A, 52: 2–20. doi: 10.1034/j.1600-0870.2000.520102.x for the EURO-CORDEX 0.11° reference/training data [[http://www.euro4m.eu/downloads/D2.4_Improved_MESAN_downscaled_dataset_at_3-12_km_resolution_for_most_of_the_past_20_yr_period.pdf |MESAN]]
-  * Gudmundsson, L., Bremnes, J. B., Haugen, J. E., and Engen-Skaugen, T., 2012: Technical Note: Downscaling RCM precipitation to the station scale using statistical transformations -- a comparison of methods. Hydrol. Earth Syst. Sci., 16, 3383-3390, doi:10.5194/hess-16-3383-2012 for the bias-correction method (quantile mapping).
+  * Gudmundsson, L., Bremnes, J. B., Haugen, J. E., and Engen-Skaugen, T., 2012: Technical Note: Downscaling RCM precipitation to the station scale using statistical transformations -- a comparison of methods. Hydrol. Earth Syst. Sci., 16, 3383-3390, doi:10.5194/hess-16-3383-2012 for the bias-correction method used by Met Norway (quantile mapping).
 ===== Description of the Met Norway method =====
-The method from the Meteorologisk institutt uses the R package [[http://cran.r-project.org/web/packages/qmap/index.html|qmap: Statistical transformations for post-processing climate model output]]. Basically, it performs a quantile mapping of the simulated time series to observed ones for each grid point. It does so by estimating values for regularly spaced quantiles of the empirical cumulative distribution function and using these estimates to perform a quantile mapping. Details on the method can be found in Gudmundsson et al. (2012, doi:10.5194/hess-16-3383-2012). The set-up includes a linear interpolation between the fitted transformed values, and simulated values lying outside the range of the training period (e.g., from climate projections) are extrapolated using the correction found for the highest quantile of the training period, as suggested by Boé et al. (2007, doi: 10.1002/joc.1602). Furthermore, the method includes an adjustment of wet-day frequencies for precipitation.
+The method from the Meteorologisk institutt uses the R package [[http://cran.r-project.org/web/packages/qmap/index.html|qmap: Statistical transformations for post-processing climate model output]]. Basically, it performs a quantile mapping of the simulated time series to observed ones for each grid point. It does so by estimating values for regularly spaced quantiles of the empirical cumulative distribution function and using these estimates to perform a quantile mapping. Details on the method can be found in Gudmundsson et al. (2012, doi:10.5194/hess-16-3383-2012). The set-up includes a linear interpolation between the fitted transformed values, and simulated values lying outside the range of the training period (e.g., from climate projections) are extrapolated using the correction found for the highest quantile of the training period, as suggested by Boé et al. (2007, doi: 10.1002/joc.1602). Furthermore, the method includes an adjustment of wet-day frequencies for precipitation. For temperature, the quantile mapping takes into account the main trend by subtracting the (5-year) mean before the quantile mapping and adding it again afterwards. This is expected to reduce the impact on the mean climate change signal.
 \\
   * For the bias-corrected EUR-11 CORDEX data, the [[http://exporter.nsc.liu.se/620eed0cb2c74c859f7d6db81742e114/|daily 0.11° MESAN data]] has been used as reference/training data covering 1989-2010. The complete historical RCM data has been used for calibration.
-  * For the bias-corrected EUR-44 CORDEX data, the [[http://www.ecad.eu/download/ensembles/ensembles.php|daily 0.44° EOBS10 data]] has been used as reference/training data covering 1981-2010. The RCM data has been restricted to the same period (1981-2010) for calibration following the [[http://www.meteo.unican.es/en/node/73279|BCIP]] experiment design
+  * For the bias-corrected EUR-44 CORDEX data, the [[http://www.ecad.eu/download/ensembles/ensembles.php|daily 0.44° EOBS12 data]] has been used as reference/training data covering 1981-2010. For calibration the RCM data has been restricted to the same period (1981-2010) following the [[http://www.meteo.unican.es/en/node/73279|BCIP]] experiment design.
+(Scripts etc.: [[procedure]])
 ===== Known issues =====
 Please note the following:
-  * There is a remaining annual biases due to the use of “only” 101 regularly spaced quantiles to estimate the empirical cumulative distribution functions.
+  * There is a small remaining overall bias due to the use of “only” 101 quantiles to estimate the empirical cumulative distribution functions within qmap. See pdfs on [[evaluation]].
-  * There is additionally a remaining seasonal biases due to the calibration process which is carried out without splitting into seasons or months.
+  * There are additional remaining seasonal biases due to the calibration process which is carried out without splitting into seasons or months. See pdfs on [[evaluation]].
-  * There are some days in the MESAN data when tasmax < tas or tas < tasmin. In the current set-up this is in handed down to the bias-corrected data.
+  * The bias-correction method does not guarantee the conservation of climate change signals. The impact on the projected changes in mean conditions is relatively small, as can be seen here:\\
+{{:clipc:ClimChangeSignal_tas.pdf|}}\\
+{{:clipc:ClimChangeSignal_pr.pdf|}}\\
+{{:clipc:ClimChangeSignal_pr_rel.pdf|}}\\
+  * There are some days in the MESAN data when tasmax < tas or tas < tasmin. In the current set-up this is handed down to the bias-corrected data.
+While the first three points are a result of the idea to keep the method **very** simple (at least for the beginning), the last point is under investigation and may be fixed in a later version.
-While the first two points are a result of the idea to keep the method **very** simple (at least for the beginning), the third point is under investigation an may be fixed in a later version.
 ----
- //[[andreas.dobler@met.no|Andreas Dobler]] 2015/07/14 14:28//
+ //[[andreas.dobler@met.no|Andreas Dobler]] 2015/07/15 11:00//