Teleconnections in the Zonally Asymmetric Height Field During the Northern Hemisphere Summer

Abstract

In order to discuss the teleconnection in the zonally asymmetric height field during the Northern Hemisphere summer, the so-called one-point correlation map is used. In the map, the correlation coefficient between 700mb or 500mb zonally asymmetric height at the reference grid point and 700mb or 500mb zonally asymmetric height at every other grid point is computed, based on the data set consisting of monthly mean height for 34 summer months (July and August for the 17 summers 1963 through 1979). The discussion is mainly focused on the case where the reference point is over the eastern part of the Asian Continent in low latitude. Two types of teleconnection map, i.e., the teleconnection map due to the yearly change of monthly mean height with zonal wavenumber 1 or 2 and that due to zonal wavenumber 5 or 6, are obtained. In the latter case, a train of waves with positive and negative correlation coefficients predominates along the latitudinal circle around 45°N. These teleconnection maps are also examined in relation to the stationary waves which are excited by stationary heat sources over the subtropics.