Modelling climate statistical parameters by MISH interpolation procedure

The MISH (Meteorological Interpolation based on Surface Homogenized Data Basis; Szentimrey and Bihari) software was developed at the Climate Department of Hungarian Meteorological Service (OMSZ) specifically for interpolation of climate elements. At OMSZ the MISH is currently using to interpolate temperature, precipitation, wind, global radiation, pressure and humidity data. The software consists of two major parts: the modelling of climate statistical parameters and the interpolation subsystem. A good quality modelling requires long homogenized data sets, but the representativity of the station system is also very important. Therefore, as many measurements as possible should be considered in the modelling process.

Interpolation in MISHv1.03 is based on statistical parameters that are determined in advance in the modelling part by using climate data series. It means that this modelling has to be done only once, before the interpolation. If the modelling is made from a homogenised data set of many stations, it is possible to interpolate well with few predictors. At the Hungarian Meteorological Service, archived data are continuously recorded and new meteorological stations are being installed. The previous MISH modelling procedure for temperature data series was done using 58 stations, but this has been renewed and, recently we estimate climate statistical parameters using data of 112 stations.

In this presentation, we present the results of the new modelling for mean, minimum and maximum temperature values. In all three cases, our results show a significant improvement on previous results. We can say that we can provide more accurate estimates with few predictors for locations in Hungary where measurements are not available. The new modelling also gives us a better understanding of the climate of the past centuries, since we can make more accurate estimates from fewer measurements. It also allows us to report climate change in more detail.