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膜内5cm地温稳定通过10-12℃即可播种为棉花适宜播种温度指标,找出地膜内5cm地温与气温的定量关系并进行地温预报,同时确定对应的日平均气温的稳定界限指标值,就成为开展棉花适宜播种期预报的关键所在。以石河子绿洲覆膜栽培棉区为研究对象,分析了2008-2014年棉区春播期膜内5cm地温、气温的变化趋势以及气温与覆膜内、外地温的关系,并建立了膜内5cm地温预报模型。结果表明：近年来石河子棉区春播期内气温和膜内外5cm地温变化趋势一致,均有所上升,且膜内5cm地温显著高于膜外地温和日平均气温。棉田覆膜内外5cm地温与气温之间显著相关（P≤0.01）,石河子棉田覆膜内5 cm地温稳定通过10-12℃时,对应的日平均气温界限范围为6.3-8.2℃;利用逐日气温建立膜内5cm地温预报模型,回代检验绝对误差平均为1.01℃,2014和2015年预报检验绝对误差分别为0.5、0.7℃。预报模型可为更好地开展棉花播种期气象服务提供参考依据 相似文献
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利用2012/2013年冬季菏泽巨野日光温室内外的逐日平均气温、最高气温、最低气温、相对湿度、日照时数和最大风速等气象观测资料,采用相关分析法确定了影响温室内最低气温的关键气象因子,采用逐步回归法和主成分分析法分别建立温室内最低气温预报模型,并用2013/2014年冬季的气象数据检验评价两种预报模型的差异。结果表明:(1)温室内最低气温与当天温室内外及前1 d温室内外的气温、相对湿度、日照时数等相关性比较显著。(2)两种方法建立的预报模型均通过了α=0.01的显著性检验,逐步回归法所建预报模型得到的整个冬季预测值与实测值的相关系数为0.82,平均绝对误差仅为0.9℃,平均相对误差仅为9%;而主成分分析法所建的预报模型得到的整个冬季预测值与实测值的相关系数为0.58,平均绝对误差为1.8℃,平均相对误差为15%。由此表明,用逐步回归法所建的温室内最低气温预报模型的准确度高于主成分分析法,可满足预测冬季温室内最低气温的业务需求。 相似文献
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利用ECMWF预报场资料和地面观测资料开展支持向量机(SVM)、卡尔曼滤波(Kalman)两种统计方法对山岳型风景区气温集成预报方法的研究,并且结合自动气象观测站气温资料进行检验。结果表明:单一的SVM方法预报准确率较高且稳定,传统的Kalman方法预报效果不太理想,对长时效预报效果较差;加权集成后,3种集成方法预报稳定性较好、准确率比单一的SVM和Kalman预报方法均有所提高。从不同预报时效的检验结果看,各预报方法最高和最低气温预报准确率随着预报时效的增加均呈现降低的趋势。绝对误差分析表明,各预报方法最高气温的平均绝对误差均低于最低气温的平均绝对误差。 相似文献
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针对西江流域的洪涝灾害,利用流域的水文参量和气象参量作为自变量,探索基于人工神经网络的洪涝预报方法。以西江流域梧州市1971~2003年超过警戒水位(17.0m)共125次作为研究对象,选取流域的水文参量和气象参量作为预报因子,对数量众多预报因子采用自然正交分解(EOF)方法,浓缩大量因子的有效信息,建立了西江流域梧州洪涝的人工神经网络预报模型。结果表明:所建立的预报模型历史拟合平均绝对百分比误差为2.21%,平均绝对误差为0.43m,预报结果平均绝对百分比误差为2.34%,平均绝对误差为0.45m,预报效果较好,可应用于实际的洪涝预报中。 相似文献
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针对西江流域的洪涝灾害，利用流域的水文参量和气象参量作为自变量，探索基于人工神经网络的洪涝预报方法。以西江流域梧州市1971～2003年超过警戒水位（17．0m）共125次作为研究对象，选取流域的水文参量和气象参量作为预报因子，对数量众多预报因子采用自然正交分解（EOF）方法，浓缩大量因子的有效信息，建立了西江流域梧州洪涝的人工神经网络预报模型。结果表明：所建立的预报模型历史拟合平均绝对百分比误差为2．21％，平均绝对误差为0．43m，预报结果平均绝对百分比误差为2．34％，平均绝对误差为0．45m，预报效果较好，可应用于实际的洪涝预报中。 相似文献
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BP神经网络在油菜花期预报中的应用 总被引：1，自引：0，他引：1
建立花期预报模型,发布观赏性植物的精准花期预报,为旅游活动提供重要参考依据,已经成为气象服务领域一个新的发展方向。为了解高淳旅游区油菜花期的变化规律,探索其预报方法,指导高淳油菜花节旅游活动,根据1985—2010年高淳站日最高气温、日最低气温、日平均气温、日降水量、日日照时数、日平均5 cm地温、日平均相对湿度和日小型蒸发量等气象观测数据,利用主成分分析法,得到其与油菜花期相关系数较大的3个主成分,即温度因子、天气因子和辐射因子,以此为输入因子,建立基于BP神经网络的油菜花期预报模型,探讨BP神经网络在花期预报领域的应用。结果表明,传统的有效积温方法预报结果与实际开花期平均相差4.25天,BP神经网络方法预报结果与实际开花期平均相差1.5天,与有效积温预报油菜花期的方法相比,BP神经网络技术具有预测结果准确率高和操作简单等特点,在花期预报领域具有广阔的应用前景。 相似文献
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利用湛江市近50年来的月平均气温时间序列资料,将卡尔曼滤波与人工神经网络方法相结合,建立了湛江气温的短期气候预测模型.试验结果表明,这种基于卡尔曼滤波的神经网络模型对湛江的平均气温具有较好的预测能力,在平均绝对误差(MAE)小于1.5℃的条件下,实际预报准确率达到91.7%,对短期气候预测的业务工作具有较高的参考价值. 相似文献
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基于地表能量守恒方程和陆面模式土壤温度计算模块,建立高速公路路面温度预报物理模型。利用2014年6月1日至2015年5月31日8个常规气象观测站和6个交通自动气象监测站逐小时观测资料对模型预报产品进行评估检验,结果表明:预报效果随提前量的减小而提高,常规站(交通站)提前1h和6h预报的平均绝对误差分别为1.64℃(1.82℃)和3.27℃和(3.69℃)。由模型对输入气象要素的敏感性分析得出:模型对2m气温最敏感,其次是相对湿度、总云量,且敏感性随着预报提前量的增加而增强。结合浙江省快速更新同化系统数值预报产品,建立浙江省高速公路路面温度预报系统,为全省提供逐12h更新、12h预报时效的逐小时高速公路路面温度精细化预报,系统提前1h和11h预报常规站(交通站)的平均绝对误差分别为2.81℃(3.23℃)和2.50℃和(2.93℃),系统对极端高(低)温预报具有较高的预报技巧。 相似文献
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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 Nio3.4 index in summer and autumn but negatively correlated in spring and winter. 相似文献
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Fei LIU Chen XING Jinbao LI Bin WANG Jing CHAI Chaochao GAO Gang HUANG Jian LIU Deliang CHEN 《大气科学进展》2020,37(7):663-670
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
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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
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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(Stl), 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
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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
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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
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Analysis of Atmospheric Boundary Layer Height Characteristics over the Arctic Ocean Using the Aircraft and GPS Soundings 
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下载免费PDF全文 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
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《大气科学进展》2014,(6)
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
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《Acta Meteorologica Sinica》2014,(6)
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