Relationship between Precipitation and Elevation in the Present Climate Reproduced by the Non-hydrostatic Regional Climate Model

Abstract

The relationship between precipitation and elevation in the present climate, reproduced by the Non-hydrostatic Regional Climate Model (NHRCM), is compared with observation to examine how well the model expresses the effect of topography. The comparison is carried out in the central region of Japan during June and July. Both reproduced and observed precipitation increases with elevation over the whole calculation domain, though the correlation is low. The correlation becomes very high when the observation points are classified into river systems. The correlation in the model is low for river systems where the correlation is also low in the observation data. The correlation in both the observation data and NHRCM becomes high in river systems where the correlation is low if they are classified in more detail. The characteristic that precipitation increases with elevation becomes clear through appropriate classification of the area. The rate of increase is different in each region. The relationship between precipitation and elevation is well reproduced in NHRCM.