双套自动气象站数据评估及其优势探讨

Data Evaluation and the Advantage of the Double Automatic Weather Stations

利用2011年1—8月安徽省休宁站、安庆站和祁门站的双套站自动气象站逐小时气温、气压等要素的观测值,对国家级台站自动气象站双套运行的结果和优缺点进行了深入分析和探讨。从缺测率上分析了双套站数据的完整性,认为双套站可以明显降低数据的缺测率,具有保证数据完整性的优点。从差值的统计数字特征以及一致率、超差率和粗差率等指标上分析了两套数据的差异性,表明双套站大部分要素(如气温、气压、相对湿度等)具有差值小、差值变化幅度小、数据之间有较高的一致率、较低的粗差率和超差率等特点,但个别要素(草面温度和5 cm地温)差异略大。运行中通过对两套数据的差值、差值的滑动平均值、差值日变化特征的监控可以及时发现数据异常、探测仪器的系统性误差等情况,从而说明双套站具有保证数据质量的潜在优势,且从一定程度解决了目前自动气象站单套运行的不足之处。

Anhui Provincial Meteorological Service starts pilot run of double automatic weather stations at na- tional weather stations in 2010. The stations are deployed in Xiuning, Anqing, Kuche and other districts, and they have been put into test run one after another since October of 2010. A detailed assessment is car- ried out to evaluate the hourly data of temperature, air pressure, relative humidity, 2 min average wind speed, 5 cm ground temperature and grass temperature of the double automatic weather stations in Xiun- ing, Anqing and Qimen from January to August of 2011. At the same time, the advantages and disadvan- tages of the double automatic weather stations are discussed. The data integrity of the double automatic weather stations is analyzed by calculating missing rate. The missing rate of air pressure of Station A is 0.38~//oo, and Station B is 0.15% in Xiuning, but rate of Station A and B both missing at the same time is only 0.07 ~. So it is considered that the double automatic weather stations can reduce missing rate, and ensuring the integrity of data. The difference of the double sets of data is discussed by the statistical features, consistent rate, rate of gross errorand out-of-tolerance rates. Through the detailed analysis, it shows that most elements （such as temperature, air pressure and relative humidity） of the double automatic weather stations have stable and smaller difference. For exam- ple, the average air pressure of station A is lower than station B in Anqing, with the difference of0.01 hPa. In 5812 effective samples of difference data, there are 1659 samples with difference of 0.0 hPa, and for 99.20/00 of all the samples, differences are within ~0, 1 hPa. The standard deviation of difference is 0.08 hPa. The difference has higher concordance rate, lower out-of-tolerance rates and lower gross error. For example, the consistency rate of temperature is 96.6% in Qimen, the out-of-tolerance rates of humidi- ty is 0.0 ~ in Xiuning, the gross error rate of air pressure is 0.0 % in Anqing. However, some elements of the double automatic weather stations have lager difference, such as the grass surface temperature and ground temperature. For example, the gross error of grass surface temperature is 12.7% in Xiuning, and the out-of-tolerance rate of ground temperature is 29.7 ~/0 in Anqing. The data evaluation shows that the abnormal data, instrument systematic error can be found through monitoring the difference and the moving average of difference data, and whether the instruments have sig- nificant changes in performance can be determined by the daily change characteristic difference data of the double data. Thus, the double automatic weather stations have the potential advantages of ensuring the quality of data, and resolve the deficiency of current automatic stations in some degree in operation.