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Using NCC/IAP T63 coupled atmosphere-ocean general circulation model (AOGCM),two 20-yr integra- tions were processed,and their ability to simulate cloud and radiation was analysed in detail.The results show that the model can simulate the basic distribution of cloud cover,and however,obvious differences still exist compared with ISCCP satellite data and ERA reanalysis data.The simulated cloud cover is less in general,especially the abnormal low values in some regions of ocean.By improving the cloud cover scheme, simulated cloud cover in the eastern Pacific and Atlantic,summer hemisphere's oceans from subtropical to mid-latitude is considerably improved.But in the tropical Indian Ocean and West Pacific the cloud cover difference is still evident,mainly due to the deficiency of high cloud simulation in these regions resulting from deep cumulus convection.In terms of the analysis on radiation and cloud radiative forcing,we find that simulation on long wave radiation is better than short wave radiation.The simulation error of short wave radiation is caused mostly by the simulation difference in short wave radiative forcing,sea ice,and snow cover,and also by not involving aerosol's effect.The simulation error of long wave radiation is mainly resulting from deficiency in simulating cloud cover and underlying surface temperature.Corresponding to improvement of cloud cover,the simulated radiation (especially short wave radiation) in eastern oceans, summer hemisphere's oceans from subtropical to mid-latitude is remarkably improved.This also brings obvious improvement to net radiation in these regions. 相似文献
995.
Wang dongping 《河南气象》2007,(Z1)
分析了2001年1月6日河南省中北部出现的区域性暴雪天气过程中天气系统的演变、物理量场,并对数值预报产品作出天气学解释。 相似文献
996.
Records of UV data started in Madrid at the beginning of the 90's decade. After some quality control on the data a seven year period from 1996 to 2002 was selected to perform an analysis of daily and seasonal variability of solar ultraviolet B (UVB) values at the centre of the Iberian Peninsula. Instruments used are a Brewer MKIV spectrophotometer and a YES UVB-1 broadband pyranometer. Both instruments provided integrated daily values according with the Diffey spectrum although they have different measurement procedures. Data statistics from each instrument for the same period and statistical relationships between daily values from both instruments are shown. As broadband YES provided a record with fewer time gaps, analysis of UVI extreme values is performed using that instrument. The relationship between UVB values with ozone, cloudiness and visible radiation has been described in several papers for different places in the world. In this paper, those relationships are shown for Madrid. A discussion about specific problems found when trying to isolate every effective factor is also included. Some of those relationships could be helpful to retrieve UVB values from other ancillary data as visible radiation and cloudiness. Finally, a detailed study for 10 days in June 1997 when the maximum record of daily values from the present time series was obtained, highlight the close correlation between total ozone content and the daily variability of UVB for similar amounts of incoming radiation. 相似文献
997.
针对当前遥感产品获取存在的问题,基于网格技术、面向网络的服务技术等提出了遥感产品虚拟化的概念,并对它的定义、相关技术、特点和优点进行了讨论。认为地球空间网格环境下的遥感产品虚拟化需要建立在松散耦合型的计算模式上,需要借助于面向服务的构架。同时,为了完成网格环境下服务的发布、咨询、资源调度、服务控制、服务生命周期控制等一系列关键步骤,必须采用能够与基于服务的构架和理念相匹配的软件工程方法,提出了基于多智能体的软件工程方法学实现遥感产品虚拟化的构想,并指出了遥感产品虚拟化是面向网格计算环境的未来遥感数据处理系统的发展方向。 相似文献
998.
宁夏区域太阳日辐射通量计算方法的研究 总被引：1，自引：0，他引：1
利用银川站过去5 a的太阳日辐射观测资料(1981~1985)与大气外太阳辐射、日照时数、日照长度间的相关关系,确定了区域系数as。通过对bs的取值进行敏感测试,可得到一组最佳推算太阳辐射通量的区域系数:as=0.3,bs=0.5。用此系数和太阳日辐射通量计算公式,推算了银川站1986、1987年太阳日辐射通量并用观测值进行验证,结果表明:两者之间有很好的线性相关,R2=0.94,验证了区域系数的可信度。通过对银川站2 a(1986,1987)资料的平均误差、平均偏差、平均绝对偏差和均方根偏差的计算表明,结果与国内相关报道基本一致。对宁夏永宁站1989~2000年的太阳日辐射通量用区域系数进行估算,并与银川站的实际观测资料比较,结果显示永宁站太阳日辐射通量估算值和银川站实测值间有很好的线性关系,12 a间的方差最小值R2=0.88。 相似文献
999.
A coal preparation plant typically operates with multiple cleaning circuits to clean individual size fractions of run-of-mine coal. Coal preparation plants are traditionally optimized using the equalization of incremental product quality approach. Individual cleaning circuits are operated at the same specific incremental product quality so that the targeted overall plant product quality is achieved. Over the years, it has been well established that equal incremental product quality approach maximizes plant-yield for a given product quality constraint. 相似文献
1000.