LISTS OF THE OBSERVATIONS USED IN THE RTMA ==================================================================================================== SECTION 1: ==================================================================================================== Notes about the observation files of the type bufr_d.listing.adpsfc.YYYYMMDDHH bufr_d.listing.msonet.YYYYMMDDHH bufr_d.listing.qkswnd.YYYYMMDDHH bufr_d.listing.sfcshp.YYYYMMDDHH bufr_d.listing.spssmi.YYYYMMDDHH These files are generated by Dennis Keyser's program that creates the RTMA prepbufr file. They list all the obs contained in the prepbufr file. ==================================================================================================== SECTION 2: ==================================================================================================== Notes about the observation files of the type: ps_obs.listing_iter_NN.YYYYMMDDHH (surface pressure) t_obs.listing_iter_NN.YYYYMMDDHH (temperature) q_obs.listing_iter_NN.YYYYMMDDHH (specific humidity) u_obs.listing_iter_NN.YYYYMMDDHH (u-wind) v_obs.listing_iter_NN.YYYYMMDDHH (v-wind) spd_obs.listing_iter_NN.YYYYMMDDHH (wind speed) 1. These files list observations that are available for use in the RTMA-GSI. NN denotes the GSI outer iteration number. In the current RTMA setup, NN=01 or 02. Note that the lists are a function of NN as the quality control decisions are made anew at the start of each outer iteration. t_obs.listing_iter_01 lists the temperature obs that were available for use at the beginning of the 1st outer iteration t_obs.listing_iter_02 lists the temperature obs that were available for use at the beginning of the 2nd outer iteration Similar meaning is true for the other ob types. These lists do NOT include (i) obs that are rejected during the initial quality screening based on the MADIS QC flags. (ii) obs with reporting times that fall outside the RTMA assimilation time window, which for most obs is (-12min to +12min) around the valid analysis time. The obs mentioned in (i) and (ii) are listed in the files t_obs_preflagged.YYYYMMDDHH q_obs_preflagged.YYYYMMDDHH uv_obs_preflagged.YYYYMMDDHH (sqrt(u**2+v**2)) ps_obs_preflagged.YYYYMMDDHH spd_obs_preflagged.YYYYMMDDHH --------- 2. Obs that are available for assimilation may in fact be rejected by one of the following RTMA quality control mechanisms: a) Ob fails the Gross Error Check b) Ob is contained in the observation reject list for that ob-type c) Ob is not a property of any of the providers listed on the "GSD mesonet wind provider-uselist" nor is it contained in the "GSD mesonet wind station-uselist". This mechanism applies only to mesonet wind obs. 3. In addition, the user can choose to withhold a given observation from the assimilation and simply monitor its fit to the guess and analysis. The user can also withhold an observation for cross-validation purposes, ie., to be part of a subset of independent observations against which to validate the analysis (or the GSI output after the first outer-iteration). 4. Observations are assimilated only if rmuse=+1. or +2.0. A negative value of rmuse means that the ob was rejected by one of the above quality control mechanisms, or that the ob was intentionally withheld as described in 3. Take t_obs.listing_iter_01 for example: rmuse=+1 means that the ob was assimilated during the first outer iteration. Note that the same ob can have a value of rmuse=-1. during the second outer iteration, meaning that it was rejected by the Gross Error Check during that iteration. A value of rmuse=-2 in t_obs.listing_iter_01 means that the ob was withheld from from the first outer iteration and was only available for assimilation during the second outer iteration. This can only happen when cross-validation is turned on, which is generally not the case in the operational use of the RTMA. Note that a value of rmuse=+2 can never occur in t_obs.listing_iter_01. Now consider t_obs.listing_iter_02: rmuse=+1 means that the ob has been available for assimilation since the first outer loop, and that it was definitely assimilated during the second outer loop. Note that the only way to know if this ob was assimilated during the first outer iteration is to search its rmuse value in t_obs.listing_iter_01. A value of rmuse=+2 in t_obs.listing_iter_02 means that the ob was only available for assimilation during the second outer iteration, and that it was indeed assimilated. A value of rmuse=-2 would mean that it failed the Gross Error Check during the second outer iteration. 5. The RTMA uses four types of observation reject lists: 4.1) The static list, which is made up of obs that the developers and forecasters find to be of sub-standard quality during regular RTMA viewing. 4.2) The lists that are periodically provided to the developers by the Weather Forecast Offices 4.3) The global list provided periodically by Josh Watson from Eastern Region. It uses MADIS QC statistics to generate lists of sub-standard obs for the whole CONUS. 4.4) The dynamic list, which is generated by the RTMA itself. It's based on Gross Error Statistics from the last few (currently up to six) analysis. 6. For T, Q, and PS obs: A value of rmuse=-5000. means that the ob was present in at least one of the reject lists. It was therefore not assimilated. The exact reject lists where the ob was found are shown in the observation files. 7. For wind obs: a) A value of rmuse=-5000. applies to non-mesonet winds only. It means the ob was present in at least one of the observation reject lists and was therefore not assimilated. b) Values of rmuse=-6000., -6100. and -6200. apply only to mesonet winds: rmuse=-6000. ==> Ob was not assimilated since it did not belong to the 'GSD mesonet wind provider-uselist' nor was it in the 'GSD mesonet wind station-uselist'. This ob was also not in the wind reject list. rmuse=-6100. ==> Ob was either in the 'GSD mesonet wind provider-uselist', or in the 'GSD mesonet wind station-uselist', or on both lists. However, it was not assimilated because it was on the wind reject list. rmuse=-6200. ==> Ob was not assimilated because it was on the wind reject list. In addition, this ob did not belong to the 'GSD mesonet wind provider-uselist' nor the 'GSD mesonet wind station-uselist'. 8. read_ob_listing.f is a small Fortran 90 file that can be used as a starting point for processing the information from the new lists. A documentation block is included in the program. /Oudated. Must make a few changes/ 17June2008 ==================================================================================================== SECTION 3: ==================================================================================================== Notes about the observation files: t_obs_preflagged.${CYCLE} q_obs_preflagged.${CYCLE} ps_obs_preflagged.${CYCLE} uv_obs_preflagged.${CYCLE} spd_obs_preflagged.${CYCLE} These files list: (a) obs that are rejected during the initial quality screening based on the MADIS QC flags. (b) obs with reporting times that fall outside the RTMA assimilation time window, which for most obs is (-12min to +12min) around the valid analysis time.