水土保持研究

降水的年内分配对作物生长、水资源利用和全球水循环具有重要的意义,而降水集中指数(Precipitation Concentration Index,PCI)能很好地表征降水在一年内的集中分散程度大小,被广泛应用于相关研究。基于甘肃省27个气象台站1961—2017年的逐月、逐日降水数据,采用Sen斜率来计算PCI值的变化趋势,并采用交叉小波和相干小波变换等方法来分析研究区PCI与若干气候环流指数之间的相互关系。结果表明:甘肃省多年平均PCI值为20.3,最大值为26.3(1980年)、最小值为16.6(2016年),表明年降水分布处于中高集中度范围。从长期趋势来看,研究区年PCI值呈下降趋势,变化递减率为-0.54/10 a; 但年内降水还是集中在某几个月份内。甘肃省年平均PCI值的空间变化趋势由西北向东南逐渐增大,这说明东南部年降水呈现出逐渐趋于集中的趋势,而该地区西北部年降水分配却有逐渐趋于均匀的趋势。从四季来看,该区域春、夏、秋季的SPCI值空间分布格局基本一致,但空间差异明显,SPCI值呈现出东南部低而西北部相对较高的空间分布特征; 冬季SPCI值在整个研究区域内空间变化差异最显著; 说明甘肃东南部和中部地区的降水在冬季分布相对均匀,而西北部冬季降水具有高度集中性,也就是降水可能发生在某一个月内。交叉小波变换和小波相干谱分析表明:甘肃省年降水集中度与大气环流指数PDO,AO,ENSO和SS等存在共振周期,但相关性在不同时域中却存在一定差异,这说明该地区年PCI变化的重要因素之一是受到大气环流指数的影响。

The precipitation concentration index(PCI)is a powerful indicator for temporal precipitation distribution and is also very useful for the assessment of seasonal precipitation changes. The primary objectives of this study are to investigate and analyze the temporal-spatial variability patterns of annual and seasonal PCI values based on monthly precipitation data. These data were collected from 27 meteorological stations located throughout Gansu Province,for the period of 1961—2017. Additionally,the possible teleconnection with the largescale circulation pattern was investigated. The results reveal that the variation trend of annual PCI values had decreased at a rate of -0.54/decade in Gansu Province over the past 57 years. The regularity of the annual precipitation pattern increased in spring,summer,and autumn from southeast to northwest of Gansu Province. However,the winter precipitation dispersion and the pattern in the considered period were more regular than those of the other seasons. Furthermore,the relationship between the PCI and PDO,AO,ENSO,and SS presented significant periodic variations with PCI,indicating that changes in the PCI appeared to be rather complex and possibly related to global atmospheric characteristics. These results presented in this study indicate that the PCI is an essential feature for water resource planning,prediction of risk due to droughts or floods,and the management of natural resources.

引言
1 数据来源与研究方法
2 结果与分析
3 讨论与结论

图1 1961-2017年甘肃省年PCI值(A)和年代际(B)PCI值的变化趋势

图2 甘肃省平均降水集中度的变化趋势及其变异系数的空间分布

图3 研究区1961-2017年各季节SPCI平均值

图4 甘肃省降水集中度(PCI)与PDO,AO,ENSO和SS的交叉小波功率谱、相干小波功率谱。

[1] 任志艳,延军平,王鹏涛.1960—2012年内蒙古降水集中度和降水集中期时空变化[J].中国沙漠,2016,36(3):760-766.
[2] 王纪军,裴铁璠,顾万龙,等.降水年内分配不均匀性指标[J].生态学杂志,2007,26(9):1364-1368.
[3] Dore M H I. Climate change and changes in global precipitation patterns:What do we know?[J]. Environment International,2005,31:1167-1181.
[4] 王红桃,包光,胡亚飞.甘肃省1967—2008年气温和降水时空变化[J].沙漠与绿洲气象,2017,11(2):34-42.
[5] 任朝霞,杨达源.西北干旱区近50年气候变化特征与趋势[J].地球科学与环境学报,2007,29(1):99-102.
[6] Frieler K,Meinshausen M,von Deimling T S,et al. Changes in global-mean precipitation in response to warming,greenhouse gas forcing and black carbon [J]. Geophysical Research Letters,2011,38(4):1-5.
[7] 段亚雯,朱克云,马柱国,等.中国区域1961—2010年降水集中指数(PCI)的变化及月分配特征[J].大气科学,2014,38(6):1124-1136.
[8] Zhang L J,Qian Y F. Annual distribution features of the yearly precipitation in China and their interannual variations [J]. Acta Meteorologica Sinica,2003,17(2):146-163.
[9] 王睆.我国夏季和全年降水集中程度与旱涝的研究[D].南京:南京信息工程大学,2015.
[10] 孔锋方,佳毅,刘凡,等.1951—2012年中国降水集中度和集中期的时空格局[J].北京师范大学学报,2015,51(4):404-411.
[11] 张录军,钱永甫.长江流域汛期降水集中程度和洪涝关系研究[J].地球物理学报,2004(4):622-630.
[12] Huang S Z,Huang Q,Chen Y T,et al. Spatial-temporal variation of precipitation concentration and structure in the Wei River basin,China[J]. Theoretical and Applied Climatology,2016,125(1/2):67-77.
[13] Shi P,Wu M,Qu S M,et al. Spatial distribution and temporal trends in precipitation concentration indices for the southwest China[J]. Water Resources Management,2015,29(11):3941-3955.
[14] 纳丽.宁夏降水集中程度与旱涝关系的研究[D].兰州,兰州大学,2011.
[15] Oliver J E. Monthly precipitation distribution:A comparative index[J]. Professional Geographer,1980,32(3):300-309.
[16] De Luis M,González-Hidalgo J C,Raventós J,et al. Distribución espacial de la concentración y agresividad de la lluvia en el territorio de la comunidad valenciana[J]. Cuaternario Y Geomorfologia,1997,11(1):33-44.
[17] Zhang K X,Yao Y L,Qian X Q,et al. Various characteristics of precipitation concentration index and its cause analysis in China between 1960 and 2016[J]. International Journal of Climatology,2019,39(12):4648-4658.
[18] Zamani R,Mirabbasi R,Nazeri M,et al. Spatio-temporal analysis of daily,seasonal and annual precipitation concentration in Jharkhand state,India[J]. Stochastic Environmental Research and Risk Assessment,2018,32(4):1085-1097.
[19] De Luis M,González-Hidalgo J C,Brunetti M,et al. Precipitation concentration changes in Spain 1946—2005[J]. Natural Hazards and Earth System Sciences,2011,11(5):1259-1265.
[20] Vyshkvarkova E,Voskresenskaya E,Martin-Vide J,et al. Spatial distribution of the daily precipitation concentration index in southern Russia[J]. Atmospheric Research,2018,203(1):36-43.
[21] 张克新,王娟娟,彭娇婷,等.贵州省降水集散程度时空变化及其影响因素分析[J].贵州师范大学学报:自然科学版,2020,38(2):10-18.
[22] Wolter K,Timlin M S. Monitoring ENSO in COADS with a seasonally adjusted principal[C]//Proc. of the 17th Climate Diagnostics Workshop,Norman,Ok,Noaa/Nmc/Cac,Nssl,Oklahoma Clim. Survey,Cimms and the School of Meteor.,Univ. of Oklahoma,1993.
[23] 张克新,董小刚,廖空太,等.1960—2017年黄河流域极端气温的季节变化特征及其与ENSO的相关性分析[J].水土保持研究,2020,27(2):187-192.
[24] Grinsted A,Moore J C,Jevrejeva S. Application of the cross wavelet transform and wavelet coherence to geophysical time series [J]. Nonlinear Processes in Geophysics,2004,11(5/6):561-566.
[25] Torrence C,Compo G P. A practical guide to wavelet analysis [J]. Bulletin of the American Meteorological Society,1998,79(1):61-78.
[26] Jevrejeva S,Moore J C,Grinsted A. Influence of the Arctic Oscillation and EI Niño-Southern Oscillation(ENSO)on ice conditions in the Baltic Sea:The wavelet approach[J]. Journal Geophysical Research,2003,108(21):4677-4686.
[27] 王红桃,包光,胡亚飞.甘肃省1967—2008年气温和降水时空变化[J].沙漠与绿洲气象,2017,11(2):34-42.
[28] 段鹏硕,刘根友,柳林涛,等.地球动力学扁率与南极涛动年际变化的小波相干分析[J].科学通报,2014,59(30):2947-2955.
[29] 靳立亚,符娇兰,陈发虎.近44年来中国西北降水量变化的区域差异以及对全球变暖的响应[J].地理科学,2005,25(5):567-572.
[30] 董林垚,张平仓,刘纪根,等.太阳黑子和ENSO对日本吉野川流域水文要素影响[J].水科学进展,2017,28(5):671-680.

备注

引言

1 数据来源与研究方法

2 结果与分析

3 讨论与结论

期刊信息