Spatiotemporal characteristics of the vertical structure of predictability and information transport in Northern Hemisphere

Abstract

Based on nonlinear prediction and information theory, vertical heterogeneity of predictability and information loss rate was obtained over the Northern Hemisphere. In seasonal to interannual time scales, the predictability is low in lower troposphere and high in mid-upper troposphere. But within mid-upper subtropics troposphere over some ocean area there is a relatively poor prediction. The conclusions fit the seasonal time scale too. When it goes to the interannual time scale, the predictability is high in lower troposphere and low in mid-upper troposphere contrary to the formers. And on the whole the interannual trend is more predictable than the seasonal trend. The average information loss rate is low over mid-east Pacific, west of North America, Atlantic and Eurasia, and the atmosphere over other places have a relatively high information loss rate in all time scales. Two channels were found steadily over the Pacific Ocean and Atlantic Ocean in subtropics. There exist unstable channels as well. The four-season impact on predictability and information communication was studied too. The predictability is low no matter what season data are removed and each season plays an important role in the existence of the channels except the winter. The predictability and teleconnections are paramount issues in atmospheric science, and the teleconnections may be established by communication channels. So this work is interesting since it reveals the vertical structure of predictability distribution and channel locations, the contribution of different time scales to them and their variations with different seasons.