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按照土壤水分自动站业务化检验标准对云南2010年建立的20个土壤水分自动站观测值进行了业务化检验,其中17个站点通过业务化检验。为评估业务检验合格站点的数据质量,对检验时段人工对比观测数据进行分析,由于检验时段多分布在雨季,大部分土壤层观测数据的样本标准差较小,导致检验后干季时的土壤自动站与人工观测结果误差较大。将各站点的土壤体积含水量绝对误差转换成土壤相对湿度误差后,土壤相对湿度误差值大于等于10%的土层占有效检验总数的24.4%;误差值小于6%的只占总数的41.2%。分析认为当前土壤水分自动站业务化检验的评判标准值得商榷和论证。 相似文献
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自动土壤水分观测站业务化检验分析 总被引：1，自引：0，他引：1
土壤水分监测对农业生产和科学研究都具有重要意义,自动土壤水分观测数据得到了广泛应用,实现了土壤水分的自动监测。通过对天津新建DZN3型自动土壤水分观测站业务化检验过程进行介绍,分析了自动观测数据的到报率和土壤常数的测定,并对人工与自动观测数据做了详细的对比分析,通过两个实例分析了对比检验的方法,确定了能够业务化运行的自动土壤水分观测站,分析了站点未通过检验的原因,并对重新进行业务化检验的站点和日常维护提出了建议,介绍的方法为今后开展相关业务化检验奠定了基础。 相似文献
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DZN2型自动土壤水分观测仪常见问题分析 总被引：3，自引：0，他引：3
根据DZN2型自动土壤水分观测仪的运行情况,结合在全国12个省(区、市)收集的设备故障和维修信息,从供电系统、采集器、传感器及数据异常变化等方面分析和说明了常见问题出现的原因,并给出了解决方法,提出了设备维护及场地维护的注意事项,旨在提高台站技术人员对设备的维护和检修能力,为仪器的日常维护检查、故障排查提供参考,也为提高自动土壤水分站运行的稳定性和数据质量的可靠性提供基础技术支持. 相似文献
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自动土壤水分观测资料应用误差分析 总被引：5，自引：0，他引：5
根据从国家气象信息中心实时资料数据库读取的自动土壤水分监测资料,对比同日人工测定的土壤相对湿度数据,发现白天各时次自动监测数据与人工监测数据之间均存在15%左右的差异。具体针对监测仪器自身的结构特点以及中国气象局的业务要求,从两种监测方法自身的监测地段代表性、数据测量和换算、监测土层深度、监测时间、土壤水分常数测算、土壤结构变化等多种角度分析数据间存在差异的原因;认为多种可以估算的差异"叠加"在一起时,对比差异最大可能达到20%左右,加上其他误差因素的影响,实际应用中出现15%左右的差异是可以解释的;选择较长序列的站点实测资料进行了数据差异的实况分析。结合业务中常用的墒情等级判断指标,分析数据差异对客观判断构成的数据干扰和数据损失。建议直接利用体积含水量进行业务应用分析,探究全新的自动土壤水分监测数据应用方法,在具体应用中建立相应的指标体系或指标模型,充分发挥自动土壤水分监测的优势。 相似文献
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FDR自动土壤水分数据标定问题及解决方法 总被引：4，自引：0，他引：4
针对目前FDR自动土壤水分数据可用性低的实际情况,本文从FDR自动土壤水分站传感器原理出发,结合数据处理流程与方法对湖南60个站点不同层次的标定参数及部分站点的相关观测数据进行了分析,指出目前田间标定法在自然条件下几乎无法得到覆盖土壤各个湿度区间的均匀样本数据,导致二次标定参数不合理是造成FDR自动土壤水分站数据可用性差的根本原因。二次标定方程参数不合理主要表现为方程斜率过大、过小、负值3种情况,导致观测数据增幅过大、常年不变、与实际土壤湿度变化趋势完全相反等问题。最后针对该问题提出了大样本原状取土,实验室标定的解决方法,并对方法进行了初步验证,结果表明该方法能从源头上有效改善土壤水分站观测数据质量。 相似文献
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自动气象站运行以后有效避免了人工观测方式下地温的误读现象,提高了地温数据质量。由于自动观测模式对仪器质量及维护方法提出了更高的要求,因此观测人员应不断提高理论水平和责任心。维护不当,自动采集的数据可能发生系统性错误。本文通过地温数据质量控制的一个实例,警醒一线观测人员。 相似文献
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根据2000年自动站和人工观测气温资料, 对两种气温序列进行了对比分析, 以了解仪器改变对观测数据产生的影响以及为换型后数据的连续使用提供科学依据。结果表明:除个别地区以外, 自动站与人工观测气温偏差都在允许范围之内或略超出允许范围, 季节性和地域性差异不大; 由于自动站温度传感器灵敏度高, 所以在日出日落、日气温最高和最低时与人工观测偏差较大; 自动站观测气温与历史序列无显著性差异。自动站可以用于业务, 但需进行一定时间的平行观测, 尤其在西北及高山站更为必要。 相似文献
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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
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Yuepeng PAN Mengna GU Yuexin HE Dianming WU Chunyan LIU Linlin SONG Shili TIAN Xuemei Lü Yang SUN Tao SONG Wendell W. WALTERS Xuejun LIU Nicholas A. MARTIN Qianqian ZHANG Yunting FANG Valerio FERRACCI Yuesi WANG 《大气科学进展》2020,37(9):933-938
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
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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
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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
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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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《大气和海洋科学快报》2013,(4):227
正AIMS AND SCOPE Atmospheric and Oceanic Science Letters (AOSL) publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. 相似文献
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《大气和海洋科学快报》2014,7(6):F0003-F0003
AIMS AND SCOPE
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
Atmospheric and Oceanic Science Letters （AOSL） publishes short research letters on all disciplines of the atmosphere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
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《大气和海洋科学快报》2014,(5):F0003-F0003
AIMS AND SCOPE Atmospheric and Oceanic Science Letters （AOSL） pub- lishes short research letters on all disciplines of the atmos- phere sciences and physical oceanography. Contributions from all over the world are welcome. 相似文献
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《大气科学进展》2014,(6)
正Aims Scope Advances in Atmospheric Sciences(AAS)is an international journal on the dynamics,physics,and chemistry of the atmosphere and ocean with papers across the full range of the atmospheric sciences,co-published bimonthly by Science Press and Springer.The journal includes Articles,Note and Correspondence,and Letters.Contributions from all over the world are welcome. 相似文献