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The issue of climate change has always been the most concerned about scientific issues in various countries, as closely related to marine environmental change, especially sea surface wind field, the development of the wave field changes with the development of the technical conditions to gradually pay attention and seventies of the last century, the rapid development. This paper summarizes the wave climate research progress on the wave climate research significance, there may be some connection, and pointed out that the development of wave climate change with the variation of the large-scale atmospheric circulation at the same time for the 1977/1978 global climate transitions discussed the corresponding changes in the wave climate characteristics. In this paper, the European mesoscale meteorological center (ECMWF) provided nearly 45 years (1957-2002) the latest global data assimilation set (ERA-40), the data set provides 4 times a day the wind field and the wave field related data. The study from which to extract a wind speed of 10 meters on the sea, the significant wave height, the average cycle, average wave to study. Thesis on the wind speed standard amount and the significant wave height global average distribution of wind speed and effective wave high there is a good correlation between, and high latitudes than in low latitudes and strong, the southern hemisphere than the northern hemisphere and strong, wind speed, wave high extrema appear in the Southern Ocean , at the same time, wind speed and wave height have a strong seasonal variation characteristics. By comparing before and after 1977/1978, found that the high latitudes of the ocean central wave height values ??increasing trend, wave height values ??close to the continental margin seems on the wane, the wind speed did not change significantly. For wind speed and significant wave height return period, using three commonly used extreme value distribution function curves (Pearson Type III curve, Gumbel curves and Weibull curve), the sample data were of yearly and monthly pole value of the return period estimated results and select Ⅲ Curve estimated global five years, 10 years, 20 years, 50-year and 100-year return period of extreme value, the wind speed and significant wave height reproduce period maxima in the North Atlantic, the minimum value in the equatorial region. The same changes in its 77/78 years ago after doing research, found signs of enhanced wind speed return period in the Pacific Northwest, especially the 50 years the extremes, and the once-in-a-century extreme values ??found no change, the significant wave height more complex changes, global enhance the area and weakened areas. Indicates that due to the large-scale atmospheric circulation variability in the ocean swell variation in This article first proposed the three indicators (wind - wave correlation coefficient, wave age and swell indicators) to describe the distribution of the global storms - swell through three indicators zonal distribution and seasonal distribution analysis, this paper gives the oceans swell the existence of long-term East (ie, there is \consistent with results of previous studies. At the same time, the seasonal variation of the average wave to found the oceans swell comes from the northern and southern hemispheres high latitudes. Change after 77/78 years ago, the Pacific swell pool after 78 years to strengthen and outward expansion, the Atlantic swell pool was significantly reduced, Pacific ocean storms dominate the area of ??the West Bank weakened after 78 years, this is consistent with the East Asian monsoon weakening trend after 78 years. Statistics has practical significance for the results of this study, selected three routes once the significant wave height and wind speed extremum frequency greater than 5 years, respectively, on the route from China's Shanghai to Vancouver, Canada and the sub-season . Ⅰ for winter sailing routes, route II for the Spring and Autumn sailing, weaker than the summer significant wave height and wind speed, the statistical results of the three routes quite. Wave climate variability has an important influence on the climate change and, therefore, its to do further detailed study has important significance to need the support of high-resolution data, particularly in the area of ??focus variation, its more profound research.
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