我国18世纪降水气候变率研究

The work succeeded in reconstructing the sequences of precipitation since 18th century and retrieving the historical annual rainfall anomaly fields , and intend to employ in addressing climate change and verifying output from numerical models..Records of Clear and Rain Weather by ex-Qing Dynasty royal officers contain the start and end of rainfall/snowfall events and dry weather recorded on a daily basis.The annual and seasonal precipitation series are reconstracted from Qing-Dynasty Weather Records for Beijing(1724-1904) Nanjing(1723-1798) Suzhou( 1736-1805) Hangzhou(1723 -1773 ) .In dealing with the reconstruction we proposed an 8-factor stepwise regression scheme, followed by making a stepwise regression formula with the numbers of days of different rainfall intensities in a month and the monthly total of rainy days as the variables to re-establish monthly precipitation total by means of the information on rainfall given in the 'Clear and Rain Records' ..Another attempt has been made to reduce grid-based anomaly fields from historical descriptions. With the aid of computers and the Chinese historical climatic records as basic data, different values were assigned to related grid points according to the descriptions and through interpolation a rainfall anomaly field was computer-retrieved in a way that denotes grid anomalies by -1, 0 and +1 at a 1-year and a 10×10 lat./long. resolution. We have thus reduced tentatively the anomaly fields in 1501-1900 annual precipitation for the eastern part of China, attaining a total of 400 grid-based maps and intend to employ in addressing climate change and verifying output from numerical models..

利用我国18世纪逐日天气记录兼及其它文献记载、代用资料和在欧洲新发现的中国18世纪器测气象记录，校准和增补18世纪气候复原序列，发表一套可供复验的基础资料，全面分析18世纪这个小冰期中的气候回暖时段之降水气候变率，对比分析近40年逐日降水记录，得出全球大范围增暖背景下，我国降水气候变率的明确结论，用于气候模拟检验和气候预测研究。