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1.
石家庄温度预报检验及影响因子分析   总被引:4,自引:0,他引:4       下载免费PDF全文
对石家庄市2004年11月-2008年3月的温度预报进行了质量检验。结果表明:石家庄最低气温和最高气温的平均绝对误差均低于2 ℃,均方根误差低于3 ℃,最低气温预报准确率明显优于最高气温。进而对温度预报误差较大的样本出现原因进行了逐日客观分析,并通过自然正交函数分解(EOF)法,对不同情形下石家庄及周边县站极端最高、最低气温EOF分解特征向量场的变化特征对比,推断出影响气温预报偏差的主要因子大致相同,焚风是导致温度预报出现较大误差的重要原因。  相似文献   

2.
李瑞英 《气象科技》2015,43(3):551-556
利用2012—2013年冬季菏泽巨野日光温室内的小气候观测资料分析了温室内最低气温、最高气温与当天及前一天温室内外各气象要素的相关性,在删选出相关显著要素的基础上,采用主成分分析法建立了温室内气温预测模型。结果表明:1温室内最低气温与当天及前1天温室内外8个气象要素的相关性比较显著,温室内最高气温与当天及前1天温室内外9个气象要素的相关性比较显著,而且各气象要素之间也存在较好的相关性。2主成分回归分别提取了影响温室内最低气温、最高气温的3个主成分因子,建立的温室内气温预测模型通过了显著性检验。3回代检验的结果为,不同天气状况下的最低气温预测值和实际值的平均绝对误差在1℃左右,不同天气状况下的最高气温预测值和实际值之间的平均绝对误差在1.5℃左右。经2013—2014年冬季的温室小气候数据应用检验结果为,不同天气状况下的最低气温、最高气温预测值与实测值的平均绝对误差分别在1.1℃和1.5℃左右,其中晴天条件下的最低气温检验效果较好,绝对误差为0.9℃,寡照天气下的最高气温检验相对较好,绝对误差为1.4℃。  相似文献   

3.
利用2020年广东省冬季气温观测资料、业务常用评分方法对ECMWF模式24~48 h预报时效内的最高、最低气温预报进行检验评估。结果表明:(1)ECMWF模式较好预报了气温的时间变化趋势,日最高、最低气温预报平均绝对误差分别为1.95和1.42℃;(2)ECWMF模式最高气温预报普遍偏低,最低气温预报误差普遍在2℃以内;最高、最低气温预报的较大偏差主要来自强冷空气及以上强度过程的降温和回温预报;(3)ECMWF模式对广东省北部的最高温度和最低温度的绝对误差都是最大的,中南部地区的气温预报绝对误差较小。  相似文献   

4.
李瑞英  任崇勇 《气象科学》2016,36(5):697-702
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   

5.
利用2014年1月—2015年12月海南海口居民住宅室内小气候观测数据和室外气象要素,基于BP神经网络构建海口住宅室内气温预测模型,通过与统计回归模型相比来综合评估模型的预测效果。结果表明:BP模型预测精度较高,不同季节预测精度存在差异,春秋季精度最高、夏季精度最差,其中地温加入对模型预测精度有较大改进。不同季节采用地温的BP模型对室内气温的预测值与观测值的均方根误差分别为0.25℃、0.62℃、0.26℃和0.52℃,平均绝对误差均小于0.5℃,即误差均在合理范围内。且预测精度(RMSE)较统计回归模型分别提高了26.5%、34.7%、56.7%和25.7%。可见该模型可以满足海口居民住宅室内气温的预测需求,可为室内居住环境、建筑能耗研究提供有效的基础数据。  相似文献   

6.
基于德国天气在线T7online(简称T7)、ECMWF细网格(简称EC)及T639三种数值模式的气温预报产品,结合本溪站气象观测资料,对三种数值模式2014年1月至2015年12月本溪市气温预报的准确率及预报误差进行了检验和分析,根据误差分析结果利用BP神经网络模型建立了本溪市数值模式气温预报误差客观化订正模型。结果表明:对于气温预报的年检验,T7、EC和T639三种数值模式的最低气温预报准确率均高于最高气温的预报准确率;对于气温预报的月检验,三种数值模式对夏季、秋季最低气温的预报效果明显优于冬季和春季,而对于最高气温的预报,T7的气温预报准确率明显优于EC和T639模式;当气温波动较大时,三种数值模式气温的预报准确率均明显下降。三种数值模式对最低气温预报的平均误差均为2.00℃以内,对最高气温的预报准确率存较大差别,T7模式最高气温的预报误差最小,T639模式气温预报的系统偏差最明显,最低气温系统偏差为-1.34℃,最高气温系统偏差为-2.87℃。根据三种数值模式气温预报误差的特征,结合BP神经网络建立本溪市气温误差预报模型对数值模式气温预报结果进行订正,订正后气温平均绝对误差由2.40℃左右降至1.40℃左右,系统偏差和均方根误差均明显缩小,气温预报准确率由50%左右提高至80%以上,数值模式气温预报准确率明显提高,具有较好的应用价值。  相似文献   

7.
日最低气温是判断作物是否遭受低温冷害的主要因子,开展日最低气温推算在作物低温冻害保险理赔服务中具有实际应用意义。本研究以贵州省为例,选取了2016年2月10、2023年1月31日(代表冬季)和2017年4月1日(代表春季)贵州省范围内的小时气温、遥感反演的夜间地表温度、地表高程、遥感水汽含量等多源数据,对数据进行预处理和质量控制后,采用相关分析法分析了不同数据与日最低气温的线性相关关系,利用相关性显著的地表温度、经度、纬度、水汽含量和高程数据构建了3个不同日期的日最低气温线性推算模型。经验证数据验证,使用线性显著参数构建的最优多元线性回归模型推算的2016年2月10、2017年4月1日和2023年1月31日的最低气温平均绝对误差(MAE)分别为1.224℃、0.894℃和1.727℃,均方根误差(RMSE)分别为1.518℃、1.201℃和2.132℃。表明采用夜间过境的卫星遥感地表温度对推算当日的日最低气温具有较好的效果,该工作对于低温农业保险应用具有一定的实用前景。  相似文献   

8.
洛阳分县温度周滚动预报系统   总被引:1,自引:0,他引:1  
利用洛阳9县(市)2002年11月~2004年9月逐日最高、最低气温资料,应用欧洲中心数值预报产品,建立了洛阳9个县(市)的温度周滚动预报方程。2004~2005年试报结果表明:24~48 h预报准确率在70%左右,绝对误差在2℃以内;24~144 h预报准确率在62%~70%之间,绝对误差在2℃左右;最低气温预报效果要好于最高气温,最低气温的绝对误差与准确率分别为1.98℃和67%,最高气温的绝对误差与准确率分别为2.28℃和61%。  相似文献   

9.
利用洛阳9县(市)2002年11月~2004年9月逐日最高、最低气温资料,应用欧洲中心数值预报产品,建立了洛阳9个县(市)的温度周滚动预报方程.2004~2005年试报结果表明 24~48 h预报准确率在70%左右,绝对误差在2 ℃以内;24~144 h预报准确率在62%~70%之间,绝对误差在2 ℃左右;最低气温预报效果要好于最高气温,最低气温的绝对误差与准确率分别为1.98 ℃和67%,最高气温的绝对误差与准确率分别为2.28 ℃和61%.  相似文献   

10.
利用1961~2015年CN05.1高分辨率的逐日最高、最低气温格点资料,计算6个极端气温指数(极端最高气温、极端最低气温、结冰日数、霜冻日数、暖日日数、冷夜日数),通过趋势分析和Mann-Kendall突变检验,考察青藏高原极端气温事件的时空变化规律。结果表明:青藏高原极端最高气温、极端最低气温的总体分布呈现西冷东暖的特征,与地形西高东低一致;该地区极端最高气温、极端最低气温及暖日日数均呈上升趋势,倾向率分别为0.25℃/10a、0.42℃/10a、2.14d/10a,极端最低气温的线性增温趋势较极端最高气温更为明显;而结冰日数、霜冻日数及冷夜日数均呈下降趋势,倾向率分别为?3.09d/10a、?4.75d/10a、?2.31d/10a;从空间分布看,青海地区极端最高气温的增温趋势最为显著,柴达木盆地是明显的升温中心;在时间变化上,极端最高气温、结冰日数、暖日日数均在1997年发生了突变。   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.
The spatial and temporal variations of daily maximum temperature(Tmax), daily minimum temperature(Tmin), daily maximum precipitation(Pmax) and daily maximum wind speed(WSmax) were examined in China using Mann-Kendall test and linear regression method. The results indicated that for China as a whole, Tmax, Tmin and Pmax had significant increasing trends at rates of 0.15℃ per decade, 0.45℃ per decade and 0.58 mm per decade,respectively, while WSmax had decreased significantly at 1.18 m·s~(-1) per decade during 1959—2014. In all regions of China, Tmin increased and WSmax decreased significantly. Spatially, Tmax increased significantly at most of the stations in South China(SC), northwestern North China(NC), northeastern Northeast China(NEC), eastern Northwest China(NWC) and eastern Southwest China(SWC), and the increasing trends were significant in NC, SC, NWC and SWC on the regional average. Tmin increased significantly at most of the stations in China, with notable increase in NEC, northern and southeastern NC and northwestern and eastern NWC. Pmax showed no significant trend at most of the stations in China, and on the regional average it decreased significantly in NC but increased in SC, NWC and the mid-lower Yangtze River valley(YR). WSmax decreased significantly at the vast majority of stations in China, with remarkable decrease in northern NC, northern and central YR, central and southern SC and in parts of central NEC and western NWC. With global climate change and rapidly economic development, China has become more vulnerable to climatic extremes and meteorological disasters, so more strategies of mitigation and/or adaptation of climatic extremes,such as environmentally-friendly and low-cost energy production systems and the enhancement of engineering defense measures are necessary for government and social publics.  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.
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   

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.
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   

17.
正While China’s Air Pollution Prevention and Control Action Plan on particulate matter since 2013 has reduced sulfate significantly, aerosol ammonium nitrate remains high in East China. As the high nitrate abundances are strongly linked with ammonia, reducing ammonia emissions is becoming increasingly important to improve the air quality of China. Although satellite data provide evidence of substantial increases in atmospheric ammonia concentrations over major agricultural regions, long-term surface observation of ammonia concentrations are sparse. In addition, there is still no consensus on  相似文献   

18.
Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn (referred to as EHRPs) and 10–30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2 (CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10–30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the ‘north high (cold), south low (warm)’ pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough, consequently leading to EHRPs. Considering the link between low-frequency circulation and EHRPs, a low-frequency wave train index (LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015–2016 indicate that EHRPs can be predicted 8–24 d in advance, with an average period of validity of 16.7 d.  相似文献   

19.
Based on the measurements obtained at 64 national meteorological stations in the Beijing–Tianjin–Hebei (BTH) region between 1970 and 2013, the potential evapotranspiration (ET0) in this region was estimated using the Penman–Monteith equation and its sensitivity to maximum temperature (Tmax), minimum temperature (Tmin), wind speed (Vw), net radiation (Rn) and water vapor pressure (Pwv) was analyzed, respectively. The results are shown as follows. (1) The climatic elements in the BTH region underwent significant changes in the study period. Vw and Rn decreased significantly, whereas Tmin, Tmax and Pwv increased considerably. (2) In the BTH region, ET0 also exhibited a significant decreasing trend, and the sensitivity of ET0 to the climatic elements exhibited seasonal characteristics. Of all the climatic elements, ET0 was most sensitive to Pwv in the fall and winter and Rn in the spring and summer. On the annual scale, ET0 was most sensitive to Pwv, followed by Rn, Vw, Tmax and Tmin. In addition, the sensitivity coefficient of ET0 with respect to Pwv had a negative value for all the areas, indicating that increases in Pwv can prevent ET0 from increasing. (3) The sensitivity of ET0 to Tmin and Tmax was significantly lower than its sensitivity to other climatic elements. However, increases in temperature can lead to changes in Pwv and Rn. The temperature should be considered the key intrinsic climatic element that has caused the "evaporation paradox" phenomenon in the BTH region.  相似文献   

20.
Storms that occur at the Bay of Bengal (BoB) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the BoB are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the BoB storm activity, and the “bimodal period” of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the “bimodal pattern” storm activity in the BoB. The analysis on sea surface temperature (SST) shows that the SSTs of all the year around in the BoB area meet the conditions required for the generation of tropical cyclones (TCs). However, the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a “two-peak” storm activity pattern. The genesis potential index (GPI) quantifies and reflects the environmental conditions for the generation of the BoB storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms.  相似文献   

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