In order to discover the range of various errors in Chinese precipitation measurements and seek a correction method, 30 precipitation evaluation stations were set up countrywide before 1993. All the stations are refer...In order to discover the range of various errors in Chinese precipitation measurements and seek a correction method, 30 precipitation evaluation stations were set up countrywide before 1993. All the stations are reference stations in China. To seek a correction method for wind-induced error, a precipitation correction instrument called the ＂horizontal precipitation gauge＂ was devised beforehand. Field intercomparison observations regarding 29,000 precipitation events have been conducted using one pit gauge, two elevated operational gauges and one horizontal gauge at the above 30 stations. The range of precipitation measurement errors in China is obtained by analysis of intercomparison measurement results. The distribution of random errors and systematic errors in precipitation measurements are studied in this paper. A correction method, especially for wind-induced errors, is developed. The results prove that a correlation of power function exists between the precipitation amount caught by the horizontal gauge and the absolute difference of observations implemented by the operational gauge and pit gauge. The correlation coefficient is 0.99. For operational observations, precipitation correction can be carried out only by parallel observation with a horizontal precipitation gauge. The precipitation accuracy after correction approaches that of the pit gauge. The correction method developed is simple and feasible.展开更多
以天山西部山区喀什河流域为典型研究区,基于1990-2000年的水文气象站点实测资料、2005年喀什河流域遥测降水数据及各时间段对应的CFSR(Climate Forecast System Reanalysis)再分析数据,通过实测站与其最近CFSR站多年月平均降水的比值,C...以天山西部山区喀什河流域为典型研究区,基于1990-2000年的水文气象站点实测资料、2005年喀什河流域遥测降水数据及各时间段对应的CFSR(Climate Forecast System Reanalysis)再分析数据,通过实测站与其最近CFSR站多年月平均降水的比值,CFSR站点处2005年的年降水量与同期遥测年降水量的比值,以及基于实测站点降水数据和各CFSR站点与实测站点最近的CFSR站点的空间关系3种方法对CFSR降水数据进行订正。借助VIC模型,分析不同订正方法下研究区径流的模拟效果。降水时间序列分析结果表明,CFSR降水数据能够较好地在时间和空间上反应喀什河流域内月降水的变化情况。径流模拟结果表明,(1)CFSR降水数据的不同订正方法对径流结果影响较为明显;(2)基于实测站点降水数据以及各CFSR站点与实测站点最近的CFSR站点的空间关系订正的所有CFSR降水,在径流模拟中表现最好,模型率定期和验证期的模型效率系数均在0.80以上,多年径流相对误差在15.0%以内。该订正方法不仅考虑了降水在时间维度上的变化,还考虑其在地理空间维度的变化,较其它两种方法在径流模拟中具有更好的应用前景。展开更多
This paper optimizes the meteorological drought assessment method in Fujian Province, China, making it more suitable for long-term serial drought statistics. Using the precipitation data of Pingtan National Basic Weat...This paper optimizes the meteorological drought assessment method in Fujian Province, China, making it more suitable for long-term serial drought statistics. Using the precipitation data of Pingtan National Basic Weather Station from 1971 to 2016, according to the optimized meteorological drought assessment method, statistics Pingtan meteorological drought process, and its characteristics analysis;through the multi-model integrated forecasting super-aggregate method, the 2011-2014 Fujian precipitation reality and the European Center, T639, WRF, Japan and other numerical forecast products were used for comparative analysis. The use of multiple regression method was used to forecast precipitation, by the localized precipitation correction scheme. The early warning method of single station meteorological drought process based on precipitation reality and precipitation forecast is obtained, and the platformization idea is proposed.展开更多
[ Objective] The research aimed to study application of the attenuation correction technology in C-band radar precipitation estimation. [ Method~ Based on CINRAD-CB radar data in Shaanxi, we conducted the attenuation ...[ Objective] The research aimed to study application of the attenuation correction technology in C-band radar precipitation estimation. [ Method~ Based on CINRAD-CB radar data in Shaanxi, we conducted the attenuation correction experiment by using iteration method and Kufa method respectively. Moreover, we conducted application expedment of the Kufa attenuation correction method in the quantitative precipitation esti- mation. [ Result~ Attenuation correction technology could compensate for attenuation problem of the echo at the distant range. Calculation result of the iteration method finally tended to that of the Kufa method. Moreover, iteration method spent more time. Therefore, Kufa attenuation correction technology was more suitable for business operation. When strong echo was near radar, generated attenuation was more obvious, and application value of the attenuation correction was bigger. Attenuation correction technology was used for quantitative precipitation estimation, which was favor- able for improving accuracy of the precipitation estimation. But we should conduct detailed planning on calculation scheme of the precipitation esti- mation because that different calculation schemes had great influences on accuracy of the quantitative precipitation estimation. [ Cendusien] This research provided a basis for improving accuracy of the quantitative precipitation estimation in Shaanxi. Key words Attenuation correction展开更多
文摘In order to discover the range of various errors in Chinese precipitation measurements and seek a correction method, 30 precipitation evaluation stations were set up countrywide before 1993. All the stations are reference stations in China. To seek a correction method for wind-induced error, a precipitation correction instrument called the ＂horizontal precipitation gauge＂ was devised beforehand. Field intercomparison observations regarding 29,000 precipitation events have been conducted using one pit gauge, two elevated operational gauges and one horizontal gauge at the above 30 stations. The range of precipitation measurement errors in China is obtained by analysis of intercomparison measurement results. The distribution of random errors and systematic errors in precipitation measurements are studied in this paper. A correction method, especially for wind-induced errors, is developed. The results prove that a correlation of power function exists between the precipitation amount caught by the horizontal gauge and the absolute difference of observations implemented by the operational gauge and pit gauge. The correlation coefficient is 0.99. For operational observations, precipitation correction can be carried out only by parallel observation with a horizontal precipitation gauge. The precipitation accuracy after correction approaches that of the pit gauge. The correction method developed is simple and feasible.
文摘以天山西部山区喀什河流域为典型研究区,基于1990-2000年的水文气象站点实测资料、2005年喀什河流域遥测降水数据及各时间段对应的CFSR(Climate Forecast System Reanalysis)再分析数据,通过实测站与其最近CFSR站多年月平均降水的比值,CFSR站点处2005年的年降水量与同期遥测年降水量的比值,以及基于实测站点降水数据和各CFSR站点与实测站点最近的CFSR站点的空间关系3种方法对CFSR降水数据进行订正。借助VIC模型,分析不同订正方法下研究区径流的模拟效果。降水时间序列分析结果表明,CFSR降水数据能够较好地在时间和空间上反应喀什河流域内月降水的变化情况。径流模拟结果表明,(1)CFSR降水数据的不同订正方法对径流结果影响较为明显;(2)基于实测站点降水数据以及各CFSR站点与实测站点最近的CFSR站点的空间关系订正的所有CFSR降水,在径流模拟中表现最好,模型率定期和验证期的模型效率系数均在0.80以上,多年径流相对误差在15.0%以内。该订正方法不仅考虑了降水在时间维度上的变化,还考虑其在地理空间维度的变化,较其它两种方法在径流模拟中具有更好的应用前景。
文摘This paper optimizes the meteorological drought assessment method in Fujian Province, China, making it more suitable for long-term serial drought statistics. Using the precipitation data of Pingtan National Basic Weather Station from 1971 to 2016, according to the optimized meteorological drought assessment method, statistics Pingtan meteorological drought process, and its characteristics analysis;through the multi-model integrated forecasting super-aggregate method, the 2011-2014 Fujian precipitation reality and the European Center, T639, WRF, Japan and other numerical forecast products were used for comparative analysis. The use of multiple regression method was used to forecast precipitation, by the localized precipitation correction scheme. The early warning method of single station meteorological drought process based on precipitation reality and precipitation forecast is obtained, and the platformization idea is proposed.
文摘[ Objective] The research aimed to study application of the attenuation correction technology in C-band radar precipitation estimation. [ Method~ Based on CINRAD-CB radar data in Shaanxi, we conducted the attenuation correction experiment by using iteration method and Kufa method respectively. Moreover, we conducted application expedment of the Kufa attenuation correction method in the quantitative precipitation esti- mation. [ Result~ Attenuation correction technology could compensate for attenuation problem of the echo at the distant range. Calculation result of the iteration method finally tended to that of the Kufa method. Moreover, iteration method spent more time. Therefore, Kufa attenuation correction technology was more suitable for business operation. When strong echo was near radar, generated attenuation was more obvious, and application value of the attenuation correction was bigger. Attenuation correction technology was used for quantitative precipitation estimation, which was favor- able for improving accuracy of the precipitation estimation. But we should conduct detailed planning on calculation scheme of the precipitation esti- mation because that different calculation schemes had great influences on accuracy of the quantitative precipitation estimation. [ Cendusien] This research provided a basis for improving accuracy of the quantitative precipitation estimation in Shaanxi. Key words Attenuation correction
