登陆我国大陆热带气旋的纬度分布特征

登陆点位置是热带气旋研究的重要课题.为消除因资料单一产生的误差, 本文采用1951-2010年中国、美国、日本三套热带气旋最佳路径资料, 分析了登陆我国大陆热带气旋频数的年际变化规律, 并研究了登陆纬度的分布和变化特征. 本文以总结三套资料一致反映的现象为主, 得到以下一些有意义的结果: 从总体上看, 中国资料集内的登陆频数比其他两套资料平均每年约多1个. 1970年后三套资料的登陆频数基本保持不变, 登陆纬度有较一致的北移, 而1970年前两者在三套资料内的变化不太一致. 从单位纬度登陆频数上看, 登陆数绝大部分集中在北纬30° 以下, 且总体上随纬度增加而减少, 其中北纬21°-23° 登陆数偏多, 北纬20°-21° 和北纬23°-24° 登陆数偏少.

Latitudinal distribution of landing tropical cyclones over mainland China

Landfall location is an important research topic in studies of tropical cyclones. For tropical cyclones that made landfall over mainland China during 1951-2010, in this work, we analyze the temporal variations in the annual landfall frequency. We first study the distribution and temporal variations in the landing latitude. To avoid the inaccuracy associated with using a single dataset, in this work we adopt three best track datasets from China, the USA, and Japan and summarize meaningful common phenomena in the three datasets: the annual landfall frequency of tropical cyclones over mainland China in the Chinese dataset is 1 more than in the other two datasets on average. Since 1970, the landfall frequency in the three datasets has shown little change, whereas the landfall latitude has shown a relatively consistent northward movement (prior to 1970, the three datasets showed different trends in frequency and latitude). The landfall frequency data, assigned to different latitude bins, show that the most tropical cyclones made landfall below 30°N and that landfall frequency decreased with latitude increasing. An anomalously large (small) number of tropical cyclones made landfall over the latitude zone of 21°N-23°N (23°N-24°N and 20° N-21°N).