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1.
贵州从江椪柑黄龙病的发生及气象条件分析   总被引:2,自引:0,他引:2  
利用贵州省从江县1981—2005-05—08逐日平均气温、降水量、蒸发量以及日平均相对湿度等气象资料,并结合椪柑果树发生黄龙病的资料分析表明:当日平均气温在22~28℃、相对湿度80%~90%,有利于黄龙病病菌的滋生和蔓延;当日平均气温≥25℃时,黄龙病的病源就开始存在;当日平均气温≥27℃、相对湿度≥80%时,有利于黄龙病的发生和传播;当连续5d平均气温≥27℃时,就能导致大面积的黄龙病病害发生、蔓延和迅速传播。  相似文献   

2.
1概述1996年6月我省的天气特点是:气温偏高,降雨稍多,气温缓降,降雨的阶段性变化明显。气温的旬分布特征是:上旬特高,旬平均气温21.7℃,比常年同期高3.7℃,是历史同期第二位,仅次于1972年的22.3℃;中旬稍高,旬平均气温20.0℃,比常年同期高0.5℃,除中西部地区比常年同期高1℃外,其它地区与常年同期相比为负距平;下旬稍低,旬平均气温20.8℃,比常年同期低0.5℃,除中部地区与常年持平外,西部和东部地区均低于常年同期,由上可见6月份我省气温是由特高逐渐转入稍低。降水的旬分布特征是:上旬特少,旬平均雨量7.6毫米…  相似文献   

3.
天气概况七月上旬天气持续晴热,旬平均气温比常年偏高1—2度。上旬未到中旬初有一次中等强度的冷空气影响,晴热天气由此开始转凉。而中旬未、到下旬前期又接连受7、8号台风影响致使中、下旬的旬平均气温持续偏低1—2度。  相似文献   

4.
利用全国740站日降水资料,采用多种统计学方法,对两湖流域雨季降水特征进行了分析。结果表明:(1)两湖流域年降水序列可分为5个阶段,其中主雨季从4月的第2候开始,持续到7月的第1候。两湖流域雨季较江淮梅雨来得早,持续的时间长。(2)雨季内以出现2个和3个主雨期模态的可能性较大。其中2个主雨期一般出现在5月上、中旬及6月中、下旬,这种模态在上世纪60年代、90年代表现明显;3个主雨期一般出现在4月中旬、5月中下旬到6月初与6月下旬至7月初,该模态在20世纪60年代后期至70年初、80年代中后期表现明显。(3)两湖流域雨季内降水的准双周(10~20 d)、30~60 d低频振荡现象明显。准双周振动在雨季中表现为5个波动,30~60 d振荡表现为3个完整的波动,波峰分别出现4月上旬、5月上旬及6月中旬,与其降水主模态有较好的对应关系。  相似文献   

5.
正江西省2017年4—6月气温略偏高,降水略偏多,日照略偏少。天气气候条件对农业生产的影响前好后差,主要气象灾害为6月中旬、下旬的暴雨,导致赣北、赣中部分地区发生洪涝,造成农作物受灾、居民财物受损,经济损失严重。4月,气温偏高,降水偏少,日照明显偏多。上旬气温持续上升,旬平均气温为22—23℃,较常年同期偏高3℃,同期日照偏多15 h,光热条件对早稻育秧及直播、棉花育苗十分有利,有效补偿了3月阴雨造成的秧苗生长缓慢、素质偏差的影响。中下旬冷空气影响偏弱,  相似文献   

6.
我省自入春以来至5月上旬,持续高温少雨,全省出现大面积的干旱。5月中旬至6月上旬,全省转入低温多雨,旱情得以解除。但自6月中旬至7月末,全省又出现持续高温少雨天气,形成了异常的干旱灾害,全省受灾面积之大,持续时间之长,受灾程度之严重,为建国以来所罕见。本文分析了1997年6月中旬~7月下旬的气候概况、气候特点、干旱严重程度及其对国民经济的影响。16月中旬~7月下旬的气候概况1.1气温6月中旬~7月下旬,全省平均气温为24.2℃,比常年高3.l℃。从全省分布看,白城地区、松原地区、四平地区大部和农安、辽源为25.0~26.2℃…  相似文献   

7.
受东亚大气环流异常影响,1998年从5月中旬末开始,内蒙古自西向东先后进入汛期,汛期开始较往年提前近1个月,而且持续时间较长,汛情十分严峻。基于全区各台站历年汛期降水数据的统计分析和1998年降水的时空分布情况及其与历年的比较分析,今年的汛期可以划分为4个阶段:(1)5月中旬末至下旬,我区西部降大-暴雨,发生洪灾;(2)6月中旬至7月中旬,我区大部普降中-大雨、局部暴雨,中部发生洪涝灾害;(3)7月下旬至8月中旬,东部多次降大-暴雨,洪涝灾害异常严重;(4)8月下旬全区降雨渐少,汛情日缓。  相似文献   

8.
利用贵州省从江县1981--2005—05—08逐日平均气温、降水量、蒸发量以及日平均相对湿度等气象资料,并结合槛柑果树发生黄龙病的资料分析表明:当日平均气温在22~28℃、相对湿度80%~90%,有利于黄龙病病菌的滋生和蔓延;当日平均气温≥25℃时,黄龙病的病源就开始存在;当日平均气温≥27℃、相对湿度≥80%时,有利于黄龙病的发生和传播;当连续5d平均气温≥27℃时,就能导致大面积的黄龙病病害发生、蔓延和迅速传播。  相似文献   

9.
10月上半月,云南连续降雨,下半月自华北到华南的旱区先后出现较大的降雨过程,对旱情有不同程度的缓和。下旬后期有一次强冷空气侵入我国。月内有5个台风生成,其中一个在广东湛江沿海登陆。 天气概况 本月,平均气温除新疆大部和广东沿海为正距平,较常年偏高1—2℃外,全国大部地区较常年偏低1—2℃(图1)。上、中旬没有强冷空气影响,降雨过程少,晴天较多,对作物的生长有利。下旬后期,全国大部地区受强冷空气影响,旬平均气温偏低2—4℃,对部分地区的作物和蔬菜的生长有一定影  相似文献   

10.
今春(3~4月)全疆大部地区气温持续偏高。进入5月中旬气温骤降,月内北疆大部气温与常年持平,南疆偏高,但6月份气温又迅速回升,全疆大部气温偏高。自今年元月份以来北疆降水持续偏少趋势在5月中下旬有所缓解,5月份北疆地区月平均降水量偏多15.2%,但降水的时空分布很不均匀;6月份北疆地区降水又呈现偏少趋势。目前伊犁地区和博乐、塔城的部分地区旱情依然严重,同时我区出现了较明显的局部灾害天气。1月平均气温和月总降水量(见表亚)5月份月平均气温除.爿匕疆爿匕部阿勒泰地区、东部的北塔山偏低1.1~1.3aC,其它地区基本正…  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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   

16.
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   

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.
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   

19.
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   

20.
Hourly outgoing longwave radiation(OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite(COMS) has been retrieved since June 2010. The COMS OLR retrieval algorithms are based on regression analyses of radiative transfer simulations for spectral functions of COMS infrared channels. This study documents the accuracies of OLRs for future climate applications by making an intercomparison of four OLRs from one single-channel algorithm(OLR12.0using the 12.0 μm channel) and three multiple-channel algorithms(OLR10.8+12.0using the 10.8 and 12.0 μm channels; OLR6.7+10.8using the 6.7 and 10.8 μm channels; and OLR All using the 6.7, 10.8, and 12.0 μm channels). The COMS OLRs from these algorithms were validated with direct measurements of OLR from a broadband radiometer of the Clouds and Earth's Radiant Energy System(CERES) over the full COMS field of view [roughly(50°S–50°N, 70°–170°E)] during April 2011.Validation results show that the root-mean-square errors of COMS OLRs are 5–7 W m-2, which indicates good agreement with CERES OLR over the vast domain. OLR6.7+10.8and OLR All have much smaller errors(~ 6 W m-2) than OLR12.0and OLR10.8+12.0(~ 8 W m-2). Moreover, the small errors of OLR6.7+10.8and OLR All are systematic and can be readily reduced through additional mean bias correction and/or radiance calibration. These results indicate a noteworthy role of the6.7 μm water vapor absorption channel in improving the accuracy of the OLRs. The dependence of the accuracy of COMS OLRs on various surface, atmospheric, and observational conditions is also discussed.  相似文献   

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