摘要
文中介绍了天气发生器BCC/RCG-WG基于谐波分析和多变量平稳过程对最高气温、最低气温、日照时数、相对湿度和平均风速等5个非降水变量的模拟模型,并根据中同669个站点1971—2000年的逐日气候资料(降水、最高气温、最低气温、日照时数、相对湿度和平均风速)计算了各站点的非降水变量的模拟参数。根据计算的模拟参数对中国各地逐日最高、最低气温和日照时数等非降水变量进行了模拟,并利用100年的逐日模拟结果和1971—2000年的实测资料对5个非降水变量在年、月平均值及极端值方面进行了比较。结果表明,BCC/RCG-WG能较好地模拟中国各地的最高气温、最低气温、日照时数等5个非降水变量,特别是模拟年平均值的效果很好。模拟与实测的年平均最高气温和最低气温的均方根误差只有0.2℃,年日照时数的均方根误差为70.9h,年平均相对湿度的均方根误差为0.6%,年平均风速的均方根误差为0.2m/s。在月平均值方面,最高气温、最低气温和日照时数的模拟值与实测值也非常接近,但相对湿度和平均风速的模拟效果不是很理想。模拟和实测的各月平均最高气温、最低气温均方根误差在0.4—0.7℃,各月平均日照时数均方根误差在10—20h,各月平均相对湿度均方根误差在4%14%,各月平均风速均方根误差在0.6—0.9m/s。对于诸如高温日数、极端最高、最低气温等极端气候事件,BCC/RCG-WG的模拟效果相对较差。
The BCC/RCG-WG is a stochastic weather generator developed for simulating daily precipitations in China.In this study it is further developed by adopting a framework based on the Fourier series with multi-variables weak stationary process assumed for daily non-precipitation variables including maximum temperature,minimum temperature,sunshine hour,relative humidity and average wind speed.These non-precipitation variables are made dependent on the simulated precipitation by the previous version of the BCC/RCG-WG for daily precipitation.Using daily observations of the five non-precipitation variables from 1971 to 2000,the parameters for each non-precipitation variable of the further developed weather generator are determined for the 669 stations all over China.Based on the estimated parameters,daily non-precipitation variables at these stations for any period of time can be simulated.A 100 year simulation is made and compared with observations during 1971-2000 in terms of annual,monthly statistics and extreme climate events.The results of monthly and annual statistics are fairly satisfactory.Root mean square error（RMSE）of annual maximum temperature,minimum temperature,sunshine hour,relative humidity and average wind speed are 0.2℃,0.2℃,70.9 h,0.6%and 0.2 m/s,respectively.The RMSEs of monthly maximum temperature, minimum temperature,sunshine hour,relative humidity and average wind speed are between 0.4-0.7℃,0.4-0.7℃.10- 20 h.4%-14%and 0.6-0.9 m/s,respectively.These demonstrate the usefulness of the weather generator BCC/RCG-WG for the five non-precipitation variables.However,simulations of extreme climate events are less satisfactory.
出处
《气象学报》
CAS
CSCD
北大核心
2011年第2期310-319,共10页
Acta Meteorologica Sinica
基金
瑞典STINT基金会资助项目
国家自然科学基金资助项目(40575057)
中国气象局2009气象新技术推广重点项目“动力模式与统计降尺度结合预测极端温度日数”
关键词
天气发生器
最高气温
最低气温
日照时数
相对湿度
平均风速
中国
Weather generator
BCC/RCG-WG
Maximum temperature
Minimum temperature
Sunshine hour
Relative humidity
Average wind speed
China
