Redistribution of 24 hour precipitation

RR_24 is the precipitation collected over the last 24 hours. The Qc1 check precipcollected_flag identifies if an RR_24 value is valid (fd=1), erroneous (fd=3) or is the accumulation (fd=2) of a number (N) of consecutive 24 hour periods, where N>1. For the case fd=2, the accumulated value shall be distributed over the N 24 hours periods.

For each day the calculated

RR_24= model_value*observed_accumulation/sumof_model_values

where the model values for the N missing values of RR_24 are calculated by an interpolation from the other stations making measurements at the same time and for which fd=1. The initial interpolation method is an inverse 2-D distance weighting. (The method of interpolation applied shall eventually be pluggable and include 3-D options.)

The calculated RR_24 updates the corrected value in the kvalobs database.

• Non-real time (Qc2).

It shall be possible to run the algorithm for

• a fixed time range or
• an arbitrary interval from a past date up to the current time
• The typeid to which the algorithm is applied

CONTROLINFO AND/OR USEINFO

Interpolation utilises data for which fd=1 [c(12)=1] and the corrections are applied to fd=2 and fhqc=0 [i.e. c(15)=0, indicated that no HQC is applied to the observation.]

TYPEID, PARAMIDS, OTHER METADATA

• Paramid=110

SPECIFICATION OF CONTROLFLAGS TO BE SET FOR EXPECTED RESULTS OF THE ALGORITHM, I.E. CONSIDER BOTH POSITIVE AND NEGATIVE RESULTS

• controlinfo fd=7

EXPECTIONS OF THE USEINFO FLAGS CORRESPONDING TO CONTROLINFO FLAG SETTINGS

• unknown

• Precipcollected_flag.pl
• Additional Qc2 space controls to determine the level of variability in the data volume
• selection of data in a wet or dry volume

These methods will have an impact on the selection of points used in the interpolation to generate model values and can lead to additional quality control flag settings.