Method for determining compound data of weather radars in an overlapping region of the monitoring regions of at least two weather radars

1. A method for determining combined data of weather radars in an overlap region of the observation regions of at least two weather radars, use being made of a two- or three-dimensional spatial grid for each of the measuring points in the overlap region, characterized in that polarimetric weather radars are used as weather radars, and initially a radar echo classification is respectively calculated for each measuring point of the spatial grid from the measurements of each individual polarimetric weather radar, a plurality of radar_echo classifications of the individual weather radar thereby being present for each measuring point, and in that a common weighting factor w i is then calculated for each radar echo classification from individual weighting factors w ij that result for each individual polarimetric weather radar and for each individual radar echo classification, a function of the common weighting factor w i being adopted in dependence on the individual weighting factors w ij , where w i =fkt(w i1 , w i2 , . . . , w iM ), i corresponding to the integer number of the radar echo classification and j corresponding to the integer number of a weather radar for a total number of M weather radars.

2. The method as claimed in claim 1 , characterized in that the individual weighting factors w ij are modified by taking account of a weighting, determined in advance, of the respective determined radar echo classification.

3. The method as claimed in claim 2 , characterized in that the weighting of the radar echo classification is undertaken by the numerical coding of weather types, and a large numerical value is used for a more highly weighted radar echo classification, the numerical coding of weather types being undertaken with the aid of the severity of the weather types, and a large numerical value is used for a severe weather type.

4. The method as claimed in claim 1 , characterized in that the individual weighting factors w ij are modified by means of a further weighting factor g j characteristic of each of the at least two respective polarimetric weather radars of the overlap region, and the individual weighting factors w ij * thus modified are used to calculate the common weighting factor w i for each radar echo classification, and a function of the common weighting factor w i is adopted in dependence on the modified individual weighting factors w ij *, where w i =fkt(w i1 *, w i2 *, . . . , w iM *).

5. The method as claimed in claim 1 , characterized in that the common weighting factor w i is formed by the mean value, the maximum, the sum or the product of the individual weighting factors w ij or individual modified weighting factors w ij *.

6. The method as claimed in claim 1 , characterized in that the modified weighting factor w ij * is formed from the individual weighting factors w ij and the further weighting factor g j , characteristic of the respective weather radar, by the mean value, the maximum, the sum or the product of the modified weighting factor w ij * and the further weighting factor g j .

7. The method as claimed in claim 6 , characterized in that the characteristic weighting factor g j is determined by taking account of the distance of the polarimetric weather radar from the measuring point, of at least one of the variables measured or derived by the polarimetric weather radar, and/or of a variable describing the measurement quality of the polarimetric weather radar.

8. The method as claimed in claim 1 , characterized in that at least one of the following variables is used as a direct measurement of the individual polarimetric weather radar: differential reflectivity, linear depolarization, differential phase shift, specific differential phase shift, polarimetric correlation coefficient, and/or reflectivity measured from at least one polarization direction, radial velocity and/or spectral width of the radial velocity.