The Atmosphere And Climate Forecast Linguistics Research

By establishing the Markov model for a long-range correlated time series (LRCS) and analysing its evolutionary characteristics, this paper defines a physical effective correlation length (ECL), which reflects the predictability of the LRCS. It also finds that the ECL has a better power law relation with the long-range correlated exponent(LRCE) of the LRCS, the predictability of the LRCS decays exponentially with the increase of LRCE. It is then applied to a daily maximum temperature series (DMTS) recorded at740stations in China between the years1960-2005and calculates the ECL of the DMTS. The results show the remarkable regional distributive feature that the ECL is about10-14days in west, northwest and northern China, and about5-10days in east, southeast and southern China. Namely, the predictability of the DMTS is higher in central-west China than in east and southeast China. In addition, the ECL is reduced by1-8days in most areas of China after subtracting the seasonal oscillation signal of the DMTS from its original DMTS; however, it is only slightly altered when the linear trend is removed from the original DMTS. Therefore, it is shown that seasonal oscillation is a significant component of daily maximum temperature evolution and may provide a basis for predicting daily maximum temperatures. Seasonal oscillation is also significant for guiding general weather predictions, as well as seasonal weather predictions.The Western Pacific subtropical high in summer contains different time scales of variation which links with different time scales of climatic factors. So we decomposed both ridge line and western extension, which characterize the location of subtropical high, into inter-decadal and inter-annual components using Fourier filter. From solar radiation and sea surface temperature, the early factors have been selected by correlation analysis. It gave reasonable physical explanation about the relationships between the factors and the components. For the decadal-scale, ridge line is closely related to early solar flux in February, the North Pacific sea surface temperature in March and Atlantic sea surface temperature in May affect the western extension through tele-connections. For annual-scale, ridge point has synchronization relationships with the equatorial eastern Pacific sea surface temperature in March and eastern equatorial Pacific in January and the equatorial Indian Ocean sea surface temperature in March effect western extension jointly. Through the above early factors it established regressive equation for inter-decadal and inter-annual components of ridge line and western extension. The results of retrospective experiment showed that the regressive model has correct performance on the major trends and movements of turning of the index changes.Applying the transfer entropy (TE), which is considered as a tool to measure the direction of information transfer in dynamic system, to measure the direction of information transfer in Lorenz system, and then verifying in actual data, include temperature difference and vertical speed, the results show below. First, for Lorenz system, the y-component(y) is information source, while the x-component(x) and z-component(z) is information exchange, and the information transfer from y to x is dominant. Second, in the western Pacific, the information transfer from temperature difference to vertical speed is dominant, compared to the information transfer from vertical speed to temperature difference in eastern equatorial Pacific. This result is evidence for the theoretical result in Lorenz system. Last, in winter the information transfer between temperature difference and vertical velocity is the strongest, in spring and autumn weaker, in summer weakest.