丰满流域汛期降水变化特征分析
作者简介:高 峰(1959-),女,吉林长春人,高级工程师,主要研究方向为应用气象及气象服务。E-mail:gaofeng585985@126.com
收稿日期: 2012-01-05
要求修回日期: 2012-01-30
网络出版日期: 2012-10-20
基金资助
国家自然科学基金面上项目(41175083)资助
The Characteristic Analysis of Precipitation Variation in Fengman Basin
Received date: 2012-01-05
Request revised date: 2012-01-30
Online published: 2012-10-20
Copyright
利用丰满流域水文站1936~2008年降水资料、1948~2008年美国国家环境预报中心(NCEP)再分析资料,通过线性趋势分析、小波分析、M-K检验分析和最大熵谱分析对该流域汛期降水量变化特征进行了分析。结果表明:丰满流域汛期降水量与年降水量均呈减少趋势,特别是近20 a和30 a降水量减少较明显,汛期降水量下降趋势倾向值在1989~2008年达到-39.2mm/10a;年降水量下降倾向值在1979~2008年达到-26.5mm/10a,汛期降水量的减少较年降水量减少的明显。汛期6月、7月降水量下降的不明显,8月、9月降水量减少相对明显。最大熵谱分析和Morlet小波分析结果表明,丰满流域汛期降水量的周期变化存在着一个8~9 a左右的降水相对短周期和一个28 a的降水长周期;利用1948~2008年NCEP再分析资料对多雨、少雨的7月、8月200 hPa、700 hPa环流形势场、850 hPa风场进行了分析,以分析流域汛期降水减少的可能原因。丰满流域降水减少的可能原因是汛期影响该流域的台风次数减少、冷涡影响天数的减少,副高偏南、偏西不利于水汽向北输送和南支系统北上的影响。
高峰 , 孙力 , 苏丽欣 , 刘实 , 沈柏竹 . 丰满流域汛期降水变化特征分析[J]. 地理科学, 2012 , 32(10) : 1282 -1288 . DOI: 10.13249/j.cnki.sgs.2012.010.1282
By use of the precipitation data from hydrological station at Fengman basin in 1936-2008, as well as the reanalysis data from National Center for Environmental Prediction (NCEP) in 1948-2008, the characteristics associated with the precipitation variation in flood season at this basin were discussed by means of linear trend analysis, wavelet analysis, M-K analysis and maximum entropy spectrum analysis. The results show that, both the total amounts of precipitation at flood season and the whole year are decreased with time in Fengman basin, especially in the recent 20 and 30 years. The precipitation at flood season decreases more than the annual precipitation, for the precipitation decrease trend values in flood season reach -39.2 mm/10a from 1989 to 2008, but those of annual precipitation are only -26.5 mm/10a from 1979 to 2008. The total amounts of precipitation decrease sharply in August and September, while little in June and July during flood season. Results from analysis of maximum entropy spectrum and Morlet wavelet show that, there are two kinds of precipitation cycles in flood season at Fengman basin. One is the relative short cycle with eight to nine years, the other is the long cycle with twenty eight years. In order to study the possible reasons about the decrease trend in flood season at Fengman basin, the circulation fields in 200 hPa and 700 hPa, and the wind fields in 850 hPa were analyzed by use of the NCEP data from 1948 to 2008. It shows that, the main reasons about the decrease trend in flood season at Fengman basin are the co-effects of the reduced amounts of Typhoon and the days of cold vortex in Northeast of China affecting this basin, as well as the unfavorable condition for water vapor conveying northwards as the subtropical high is more southerly and westerly than usual, and the northward movement of the weather systems on the south.
Key words: cycle; precipitation; characteristics; Fengman basin
Fig.1 Precipitation of hydrologic and meteorological stations over Fengman basin in flood season图 1 丰满流域水文站与气象站汛期降水量 |
Table 1 The precipitation trends tend value in Fengman basin (mm/10a)表1 丰满流域降水趋势倾向值(mm/10a) |
时间(年) | 6月 | 7月 | 8月 | 9月 | 6~9月 | 年 |
---|---|---|---|---|---|---|
1936~2008 | -0.3 | 1.4 | -1.7 | -5.9 | -6.9 | -9.3 |
1939~2008 | -0.8 | 0.3 | -1.2 | -5.4 | -7 | -9.2 |
1949~2008 | -0.6 | -0.5 | -1.8 | -3.5 | -6.3 | -9 |
1959~2008 | 2.4 | -0.5 | -5.5 | -7.2 | -10.8 | -9.9 |
1969~2008 | -3.1 | 0.51 | 0.6 | -5.6 | 2.5 | 1.8 |
1979~2008 | -9.6 | -5.7 | 1.1 | -9.9 | -24 | -26.5 |
1989~2008 | -2.1 | -25.4 | 5.7 | -17.7 | -39.2 | -20.9 |
1999~2008 | -0.6 | 6.3 | 0.4 | 2.4 | 8.6 | 10.4 |
Fig.2 The variation of precipitation over Fengman basin in flood season from 1936 to 2008图 2 1936~ 2008年丰满流域汛期降水变化(a降水量; b降水距平百分率) |
Fig.3 Maximum entropy spectral analysis of precipitation over Fengman basin in flood season from 1936 to 2008图 3 1936 ~2008 年丰满流域汛期降水量最大熵谱分析 |
Fig. 4 Morlet wavelet analysis of precipitation over Fengman basin from 1936 to 2008图 4 1936~2008年丰满流域降水量 Morlet 小波分析(a年降水量;b 汛期降水量) |
Fig.5 Anomalies of geopotential height (a:200 hPa; b:700 hPa; unit:dagpm) and wind field (c: 850hPa ) during rainy years图5 多雨年高空环流形势高度距平场(a:200hPa; b:700hPa:单位:位势什米)和距平风场(c:850hPa) |
Fig.6 Anomalies of geopotential height ( a:200 hPa b:700 hPa ) and wind field ( c: 850hPa ) during rainless years图6 少雨年高空环流形势高度距平场 (a:200hPa; b:700hPa)和距平风场(c:850hPa) |
Fig.7 Change and trend of subtropical high index from 1951 to 2008(a:chartsa Index of subtropical high ridge; b: Index of the northern of the subtropical high; c: Index of subtropical high extends westward)图 7 1951~2008年丰满流域副高指数变化曲线及趋势 (a:副高脊线指数;b:副高北界指数;c:副高西伸指数) |
Fig.8 The number and trend of effect days of Northeast cold vortex from 1951 to 2008图 8 1951~2008年东北冷涡影响天数及趋势 |
The authors have declared that no competing interests exist.
[1] |
|
[2] |
|
[3] |
|
[4] |
|
[5] |
|
[6] |
|
[7] |
|
[8] |
|
[9] |
|
[10] |
|
[11] |
|
[12] |
|
[13] |
|
[14] |
|
[15] |
|
[16] |
|
[17] |
|
[18] |
|
[19] |
|
[20] |
|
[21] |
|
/
〈 |
|
〉 |