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1.
钦州市甘蔗产量年景气象预测方法研究   总被引:1,自引:1,他引:1  
姚学华 《广西气象》2002,23(4):45-47,38
应用模糊综合评判的方法,建立了钦州市甘蔗产量年景与前期关系较密切的5个大气环流因子在不同的预报等级下各个因子区间的隶属度矩阵,以此作为模糊变换矩阵R及因子权重A的备选因素,然后,根据不同年份的因子值来构造R和A,应用模糊数学的运算法则,得到甘蔗产量年景的预测结果。  相似文献   

2.
本文先用五年滑动平均方法对广西灵山县荔枝亩产量进行处理,在求出气候产量(Ym)的基上础划分出产量年景,并以Ym为样本,找出相关系数高、且又具有生物学特性的6个气象因子来反映产量年景的气侯特征,然后运用模糊相似优先比方法对产量年景作出评价。  相似文献   

3.
应用模糊综合评判的方法,建立了桂中春季低温阴雨总日数与前期5个预报因子在不同的预报等级下各个因子区间的隶属度矩阵,以此作为模糊变换矩阵R~及因子权重A~的备选元素,然后,根据不同年份的因子值来构造R~和A~,由算子M(·,0)作出预报等级的归属评判,其准确率要比目前气象部门所用的预报方法高15-20%。  相似文献   

4.
使用天门市1971~1994年小麦产量资料及其同期气象资料,采取模糊统计方法,建立了预报小麦产量年景的隶属函数,并分析了多个气象因子对小麦产量的隶属程度。结果表明,运用模糊数学中的隶属函数作小麦产量年景预报是可行的,通过回代检验,其历史拟合率达83.3%。  相似文献   

5.
本文应用灰色系统理论GM(1,1)的建模方法和回归分析方法,建立了广西甘蔗产量年景的超长期预测模型,预报的效果是令人满意的。  相似文献   

6.
先用调和权重法将夏粮气象产量分离出来,再通过相关分析筛选出与产量关系密切的大气环流因子,最后用模糊综合评判及逐步回归等方法建立了夏粮产量丰欠年景预测模型并已投入业务使用。  相似文献   

7.
利用顺德1981—1990年10年的甘蔗产量数据和气象观测资料,选取降雨量、日照时数、风速等与甘蔗产量相关气象因子进行模糊聚类分析分类,得到5类产量类型:增产(1981)、偏增(1982、1984—1986、1989—1990)、平产(1983)、偏减(1987)、减产(1988)。应用1991年预报年相关气象因子对甘蔗产量试报,结果属于偏增类,与实况一致,表明这种聚类预报方法预报效果良好,可推广使用。  相似文献   

8.
苏永秀  陈靖 《广西气象》1997,18(1):41-43
先用调和权重法将夏粮气象产量分离出来,再通过个关分析筛选出与产量关系密切的大气环流因子,最后用模糊综合主送及逐步回归等方法建立了夏粮产量丰欠年景预测模型并已投入业务使用。  相似文献   

9.
用模糊聚类法预报冬小麦产量趋势   总被引:1,自引:0,他引:1  
利用长安气象观测站10a的冬小麦生育期、产量及气象观测资料,用回归分析确定出冬小麦生育期的冬前分蘖、拔节到孕穗期降水量、开花到乳熟期的降雨日数3个因子与冬小麦产量相关显。然后利用这3个因子进行模糊聚类,并用预报年的相关资料计算做出产量趋势预报。对1999年2000年西安地区产量年景试报,预报结果正确。  相似文献   

10.
本文是运用模糊数学的原理,建立预报因子x_i对甘蔗产量的丰产事件(A)的隶属函数,并按并、交运算法则,建立Fuzzy逻辑预报方程。一、资料来源和处理甘蔗产量资料来源于贵县统计局和糖业办公室,气象资料来源于贵县气象站。  相似文献   

11.
Using the International Comprehensive Ocean-Atmosphere Data Set(ICOADS) and ERA-Interim data, spatial distributions of air-sea temperature difference(ASTD) in the South China Sea(SCS) for the past 35 years are compared,and variations of spatial and temporal distributions of ASTD in this region are addressed using empirical orthogonal function decomposition and wavelet analysis methods. The results indicate that both ICOADS and ERA-Interim data can reflect actual distribution characteristics of ASTD in the SCS, but values of ASTD from the ERA-Interim data are smaller than those of the ICOADS data in the same region. In addition, the ASTD characteristics from the ERA-Interim data are not obvious inshore. A seesaw-type, north-south distribution of ASTD is dominant in the SCS; i.e., a positive peak in the south is associated with a negative peak in the north in November, and a negative peak in the south is accompanied by a positive peak in the north during April and May. Interannual ASTD variations in summer or autumn are decreasing. There is a seesaw-type distribution of ASTD between Beibu Bay and most of the SCS in summer, and the center of large values is in the Nansha Islands area in autumn. The ASTD in the SCS has a strong quasi-3a oscillation period in all seasons, and a quasi-11 a period in winter and spring. The ASTD is positively correlated with the Nio3.4 index in summer and autumn but negatively correlated in spring and winter.  相似文献   

12.
<正>The Taal Volcano in Luzon is one of the most active and dangerous volcanoes of the Philippines. A recent eruption occurred on 12 January 2020(Fig. 1a), and this volcano is still active with the occurrence of volcanic earthquakes. The eruption has become a deep concern worldwide, not only for its damage on local society, but also for potential hazardous consequences on the Earth’s climate and environment.  相似文献   

13.
The moving-window correlation analysis was applied to investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the synchronous autumn precipitation in Huaxi region, based on the daily precipitation, sea surface temperature (SST) and atmospheric circulation data from 1960 to 2012. The correlation curves of IOD and the early modulation of Huaxi region’s autumn precipitation indicated a mutational site appeared in the 1970s. During 1960 to 1979, when the IOD was in positive phase in autumn, the circulations changed from a “W” shape to an ”M” shape at 500 hPa in Asia middle-high latitude region. Cold flux got into the Sichuan province with Northwest flow, the positive anomaly of the water vapor flux transported from Western Pacific to Huaxi region strengthened, caused precipitation increase in east Huaxi region. During 1980 to 1999, when the IOD in autumn was positive phase, the atmospheric circulation presented a “W” shape at 500 hPa, the positive anomaly of the water vapor flux transported from Bay of Bengal to Huaxi region strengthened, caused precipitation ascend in west Huaxi region. In summary, the Indian Ocean changed from cold phase to warm phase since the 1970s, caused the instability of the inter-annual relationship between the IOD and the autumn rainfall in Huaxi region.  相似文献   

14.
The atmospheric and oceanic conditions before the onset of EP El Ni?o and CP El Ni?o in nearly 30 years are compared and analyzed by using 850 hPa wind, 20℃ isotherm depth, sea surface temperature and the Wheeler and Hendon index. The results are as follows: In the western equatorial Pacific, the occurrence of the anomalously strong westerly winds of the EP El Ni?o is earlier than that of the CP El Ni?o. Its intensity is far stronger than that of the CP El Ni?o. Two months before the El Ni?o, the anomaly westerly winds of the EP El Ni?o have extended to the eastern Pacific region, while the westerly wind anomaly of the CP El Ni?o can only extend to the west of the dateline three months before the El Ni?o and later stay there. Unlike the EP El Ni?o, the CP El Ni?o is always associated with easterly wind anomaly in the eastern equatorial Pacific before its onset. The thermocline depth anomaly of the EP El Ni?o can significantly move eastward and deepen. In addition, we also find that the evolution of thermocline is ahead of the development of the sea surface temperature for the EP El Ni?o. The strong MJO activity of the EP El Ni?o in the western and central Pacific is earlier than that of the CP El Ni?o. Measured by the standard deviation of the zonal wind square, the intensity of MJO activity of the EP El Ni?o is significantly greater than that of the CP El Ni?o before the onset of El Ni?o.  相似文献   

15.
Various features of the atmospheric environment affect the number of migratory insects, besides their initial population. However, little is known about the impact of atmospheric low-frequency oscillation(10 to 90 days) on insect migration. A case study was conducted to ascertain the influence of low-frequency atmospheric oscillation on the immigration of brown planthopper, Nilaparvata lugens(Stl), in Hunan and Jiangxi provinces. The results showed the following:(1) The number of immigrating N. lugens from April to June of 2007 through 2016 mainly exhibited a periodic oscillation of 10 to 20 days.(2) The 10-20 d low-frequency number of immigrating N. lugens was significantly correlated with a low-frequency wind field and a geopotential height field at 850 h Pa.(3) During the peak phase of immigration, southwest or south winds served as a driving force and carried N. lugens populations northward, and when in the back of the trough and the front of the ridge, the downward airflow created a favorable condition for N. lugens to land in the study area. In conclusion, the northward migration of N. lugens was influenced by a low-frequency atmospheric circulation based on the analysis of dynamics. This study was the first research connecting atmospheric low-frequency oscillation to insect migration.  相似文献   

16.
基于最新的GTAP8 (Global Trade Analysis Project)数据库,使用投入产出法,分析了2004年到2007年全球贸易变化下南北集团贸易隐含碳变化及对全球碳排放的影响。结果显示,随着发展中国家进出口规模扩张,全球贸易隐含碳流向的重心逐渐向发展中国家转移。2004年到2007年,发达国家高端设备制造业和服务业出口以及发展中国家资源、能源密集型行业及中低端制造业出口的趋势加强,该过程的生产转移导致全球碳排放增长4.15亿t,占研究时段全球贸易隐含碳增量的63%。未来发展中国家的出口隐含碳比重还将进一步提高。贸易变化带来的南北集团隐含碳流动变化对全球应对气候变化行动的影响日益突出,发达国家对此负有重要责任。  相似文献   

17.
正ERRATUM to: Atmospheric and Oceanic Science Letters, 4(2011), 124-130 On page 126 of the printed edition (Issue 2, Volume 4), Fig. 2 was a wrong figure because the contact author made mistake giving the wrong one. The corrected edition has been updated on our website. The editorial office is sincerely sorry for any  相似文献   

18.
19.
Index to Vol.31     
正AN Junling;see LI Ying et al.;(5),1221—1232AN Junling;see QU Yu et al.;(4),787-800AN Junling;see WANG Feng et al.;(6),1331-1342Ania POLOMSKA-HARLICK;see Jieshun ZHU et al.;(4),743-754Baek-Min KIM;see Seong-Joong KIM et al.;(4),863-878BAI Tao;see LI Gang et al.;(1),66-84BAO Qing;see YANG Jing et al.;(5),1147—1156BEI Naifang;  相似文献   

20.
正Journal of Meteorological Research is an international academic journal in atmospheric sciences edited and published by Acta Meteorologica Sinica Press,sponsored by the Chinese Meteorological Society.It has been acting as a bridge of academic exchange between Chinese and foreign meteorologists and aiming at introduction of the current advancements in atmospheric sciences in China.The journal columns include Articles.Note and Correspondence,and research letters.Contributions from all over the world are welcome.  相似文献   

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