共查询到16条相似文献，搜索用时 171 毫秒
1.
BCC_AGCM大气环流模式异构众核加速技术 总被引：1，自引：0，他引：1
针对未来高性能计算在CPU混合架构上的发展趋势,本文对大气环流模式BCC_AGCM中的部分核心段在混合架构的神威·太湖之光高性能计算机系统上进行众核加速分析与优化。文中以核心段quad为例,通过对代码内容结构重写和使用OpenACC语言对程序进行运行指示的方式,将该核心段成功移植加速并通过了结果正确性验证。结果表明,使用OpenACC语言能够以对源代码的较小改动来获得一定的加速比,在异构环境中源代码优化加速提升的效果取决于程序结构、循环并行颗粒度以及地址连续性。 相似文献
2.
开展气象数值模式在神威·太湖之光系统的移植与优化,对研究模式与新型计算架构的适应性有重要意义。该文以BCCAGCM模式为研究对象,将其移植到神威·太湖之光全国产异构众核计算系统,进行性能分析,对模式动力框架和物理过程计算结构进行调整,将计算核心段采用OpenACC技术进行众核加速优化,大量代码进行算法重构。结果表明:各核心段计算效率基本达到未优化的3倍左右,最高可达14倍左右,将各核心段集成,形成异构众核集成版本,可正确、稳定运行,计算误差合理。在不同并行规模,采用从核对模式整体计算进行加速效果比较稳定,基本保持在1.9倍,26000核并行规模动力试验并行效率约70%,其他试验约为57%。 相似文献
3.
两个大气环流模式SAMIL和BCC_AGCM对北半球冬季极涡振荡的模拟对比 总被引：1，自引：1，他引：1
基于与NCEP再分析资料的比较, 本文利用大气环流模式SAMIL和北京气候中心大气环流模式BCC_AGCM的1950～1999年的AMIP试验模拟数据, 对北半球冬季环流及平流层极涡振荡的模拟性能进行了评估分析。结果表明两个模式都可以再现北半球环流基本型以及环流振荡的主导模态。对冬季气候平均态的模拟, 两个模式模拟的热带—热带外温度梯度均偏大, 极夜急流偏强, 极涡偏冷偏强;100～20 hPa平均位势高度场谐波分析表明两个模式模 拟的行星波偏弱;气候平均的10 hPa极夜急流均存在1个月的季节漂移, 200 hPa副热带西风急流较NCEP偏弱。两个模式模拟的环流变化的主导模态均代表极涡振荡, SAMIL极涡振荡的强度大于BCC_AGCM, BCC_AGCM极涡振荡的频率要高于SAMIL。连续功率谱分析表明, NCEP资料中极涡振荡存在4.6个月的显著周期, 相应地, SAMIL中为5.5个月的显著周期, BCC_AGCM中为4.8个月。NCEP资料中的极涡振荡主要发生在12～3月, SAMIL模拟的极涡振荡主要发生在2～3月, BCC_AGCM模拟的极涡振荡主要发生在2～4月。 相似文献
4.
初值协调性对模式数值积分结果的影响 总被引：2，自引：1，他引：1
利用国家气候中心新一代全球大气环流模式BCC_AGCM2.0.1,考虑了初值协调性对模式数值积分结果的影响,进行了两组数值回报试验(简称S1,S2),对27年(1980～2006年)的夏季基本气候态进行了对比分析,并考察了该模式对夏季气候的回报技巧。使用交叉检验的方法,计算了对模式结果的评估参数值,包括时间和空间距平相关系数,对该模式性能进行了评估和检验。结果表明,BCC_AGCM2.0.1对季节尺度的大气环流场具有良好的模拟性能,模式基本上再现了观测位势高度场、温度场、流场的分布特征以及大尺度降水分布特征。500 hPa位势高度、温度空间距平相关系数对比表明,平均而言,500 hPa位势高度、温度的空间距平相关性,热带区域(30°S～30°N)高于东亚区域(0°～60°N,60°E～150°E)和全球区域。回报与观测的降水距平百分率相关系数分布对比表明,试验S2在我国江淮地区及南方地区的回报技巧要明显优于S1。 相似文献
5.
McICA云—辐射方案在国家气候中心全球气候模式中的应用与评估 总被引：6，自引：1，他引：5
本文将一种新的、可以灵活给出云的次网格结构的蒙特卡洛独立气柱近似 (McICA) 云—辐射方案应用于国家气候中心全球气候模式BCC_AGCM 2.0.1中;由于此方案会引入一定的随机误差,本文对随机误差的特征和对所模拟的气候场的影响进行了分析和评估.结果表明,McICA随机误差引起的模拟扰动很小,随机误差对所模拟的各种气候变量影响也很小,全球平均值与作为参考的精确独立气柱近似 (ICA) 计算的差别都在0.01%量级,模拟结果的纬向分布、垂直分布和典型区域内的分布等气候特征都基本上与ICA一致.因此,在国家气候中心全球气候模式BCC_AGCM 2.0.1中应用McICA云—辐射方案具有较高的可信度,模拟性能的提升仍然主要取决于模式物理过程、动力框架等方面,而不受随机误差的影响.考虑到McICA方案下云和辐射过程是各自独立的,云的结构调整和辐射模式的改进都更为简便,为模式在未来的进一步改进提供了很大便利和发展空间. 相似文献
6.
BCC_CSM气候系统模式移植优化及其气候模拟验证 总被引：1，自引：0，他引：1
为了提高BCC_CSM气候系统模式运行效率,保障业务科研工作的顺利开展,进行BCC_CSM气候系统模式在IBM高性能计算系统的移植工作;通过性能优化使BCC_CSM模式运行效率显著提高,通过气候要素形势场分布和相对误差量化指标对BCC_CSM气候系统模式模拟性能进行验证。结果表明：移植优化后,BCC_CSM气候系统模式计算效率提高为原来的1.4倍;基于CMIP5 piControl试验,完成531-540年10 a的气候模拟,年平均地表气温形势场分布合理,相对误差小于0.5%,BCC_CSM气候系统模式计算和模拟性能均能满足应用需求。 相似文献
7.
魏敏罗勇王兰宁董敏李清泉徐影 《应用气象学报》2005,16(3):408-412
气候模式不断发展的同时，对高性能计算机提出了更高的要求，如何提高模式在现有计算机资源上的运行效率问题已越来越重要。文章介绍了利用编译器优化和手工优化技术对海气耦合模式进行优化试验，优化后模式运行效率提高60%，表明将这些优化方法应用到气候模式的改进工作中，可以达到较好的效果。 相似文献
8.
使用国家气候中心新一代大气环流模式BCC_AGCM2.0(T106L26)进行22 a夏季(6-8月)、11个成员的集合回报试验;针对500 hPa高度场、降水和气温的预测能力进行交叉检验,并计算其均方根误差.结果表明:模式对热带地区、海洋和欧亚大陆部分地区500 hPa高度场的模拟较好;对我国长江中下游、华南大部分地区降水的模拟具有一定可信度;2m温度距平在我国北方大部分地区呈现正相关且相关系数通过90％的信度检验,在南方地区则有待改善.集合预报效果好于单样本预报.模式分辨率的提高在一定程度上有助于改进预报效果. 相似文献
9.
采用消息传递方式 (MPI) 对最近发展的广州区域数值预报模式进行了并行化计算研究。根据模式的结构和计算过程特点, 模式适合采用水平分区方案进行并行计算处理。在曙光3000并行计算机上分别采用一维和二维分区并行方案实现了模式的并行化计算, 并对模式的并行效率、并行加速比和并行通讯时间百分比等做了测试。对测试结果的分析表明:采用8个CPU时, 两种方案都能在1 h内完成72 h的预报, 一维分区方案的并行效率则保持在90 %左右, 可以满足业务运行需要。当模式使用8个以上CPU时, 通讯时间迅速增加并超过了计算时间的50%, 模式并行效率明显下降。CPU相同时, 模式一维分区并行方案比二维分区并行方案并行效率高且实现起来简单。 相似文献
10.
中国东部云-降水对应关系的分析与模式评估 总被引：2，自引：1，他引：1
为评估和改进模式中不同类型云与降水的对应关系,利用1998—2007年卫星-台站融合降水资料和国际卫星云气候计划的卫星观测云资料,采用诊断方法分析了中国东部季风区冬季层云、夏季对流云、层云与降水的水平分布及季节变化对应关系,并评估了BCC_AGCM模式的T42和T106分辨率版本对云-降水对应关系的模拟能力。观测资料分析结果表明,中国东部冬季云带和雨带都稳定少动,降水主要来自雨层云和高层云,南部沿海层云和层积云也对降水有贡献;夏季,中国东部表现为层积混合云降水特征,对流云带与降水带具有较好的对应关系,并具有一致的移动特征。对流降水主要来自深对流云和卷层云,深对流云云量和降水中心完全吻合,卷层云云带则表现出比深对流云主体和降水带偏北的现象;层云降水主要来自高层云和层积云。模式评估结果表明,中、低分辨率版本的BCC_AGCM模式均模拟出了冬季层云和稳定少动的降水带、夏季深对流云、卷层云和降水带的对应关系及随季风推进的移动特征。与T42模式版本相比,T106模式版本在夏季对流云云量的模拟及其与降水带的对应关系方面有所改善,说明改进的BCC_AGCM积云对流参数化方案与高分辨率模式网格更匹配,但冬季层云云量模拟误差变大,与降水带的对应关系变差,其原因值得进一步分析研究。 相似文献
11.
The Beijing Climate Center atmospheric general circulation model: description and its performance for the present-day climate 总被引：15，自引：0，他引：15
Tongwen Wu Rucong Yu Fang Zhang Zaizhi Wang Min Dong Lanning Wang Xia Jin Deliang Chen Laurent Li 《Climate Dynamics》2010,34(1):149-150
The Beijing Climate Center atmospheric general circulation model version 2.0.1 (BCC_AGCM2.0.1) is described and its performance
in simulating the present-day climate is assessed. BCC_AGCM2.0.1 originates from the community atmospheric model version 3
(CAM3) developed by the National Center for Atmospheric Research (NCAR). The dynamics in BCC_AGCM2.0.1 is, however, substantially
different from the Eulerian spectral formulation of the dynamical equations in CAM3, and several new physical parameterizations
have replaced the corresponding original ones. The major modification of the model physics in BCC_AGCM2.0.1 includes a new
convection scheme, a dry adiabatic adjustment scheme in which potential temperature is conserved, a modified scheme to calculate
the sensible heat and moisture fluxes over the open ocean which takes into account the effect of ocean waves on the latent
and sensible heat fluxes, and an empirical equation to compute the snow cover fraction. Specially, the new convection scheme
in BCC_AGCM2.0.1, which is generated from the Zhang and McFarlane’s scheme but modified, is tested to have significant improvement
in tropical maximum but also the subtropical minimum precipitation, and the modified scheme for turbulent fluxes are validated
using EPIC2001 in situ observations and show a large improvement than its original scheme in CAM3. BCC_AGCM2.0.1 is forced
by observed monthly varying sea surface temperatures and sea ice concentrations during 1949–2000. The model climatology is
compiled for the period 1971–2000 and compared with the ERA-40 reanalysis products. The model performance is evaluated in
terms of energy budgets, precipitation, sea level pressure, air temperature, geopotential height, and atmospheric circulation,
as well as their seasonal variations. Results show that BCC_AGCM2.0.1 reproduces fairly well the present-day climate. The
combined effect of the new dynamical core and the updated physical parameterizations in BCC_AGCM2.0.1 leads to an overall
improvement, compared to the original CAM3. 相似文献
12.
The coherent interdecadal changes of East Asia climate in mid-summer simulated by BCC_AGCM 2.0.1 总被引：1，自引：0，他引：1
Haoming Chen Rucong Yu Jian Li Xiaoge Xin Zaizhi Wang Tongwen Wu 《Climate Dynamics》2012,39(1-2):155-163
This study proposes primary diagnostic metrics to evaluate the integrated structure of interdecadal changes of East Asian climate in mid-summer (July–August) over the recent half-century (1955–2000) in numerical models. The metrics are applied to comprehensively examine the performance of BCC_AGCM (Beijing Climate Center atmospheric general circulation model) version 2.0.1. When forced by historical sea surface temperatures (SST), the ensemble simulation with the BCC_AGCM reasonably reproduced the coherent interdecadal changes of rainfall, temperature and circulation. The main feature of the “southern-flooding-and-northern-drought” rainfall change is captured by the model. Correspondingly, the tropospheric cooling in the upper and middle troposphere, the southward shift of upper level westerly jet and weakening of the low-level southwesterly monsoon flow are also reproduced, as well as their relationships with rainfall changes. One of the main deficiencies of the simulation is that the amplitudes of the changes of tropospheric cooling and large-scale circulation are both much weaker than those in reanalysis, and they are consistent with the rainfall deficiency. Also, the upper and middle troposphere cooling center and decreasing of upper-level westerly jet axis shift westward in the model simulations compared with that in the observations. Overall, although BCC_AGCM shows problems in simulating the interdecadal changes of East Asia climate, especially the amplitude and locations of change centers, it reasonably represents the observed configuration of rainfall variation and the associated coherent temperature and circulation changes. Therefore, it could be further used to discuss the mechanisms of the interdecadal variation in East Asia. Meanwhile, the reasonably reproduced configuration of rainfall and its associated large-scale circulation by SST-forced runs indicate that the interdecadal variations in East Asia could mostly arise from the regional response to the global climate change. 相似文献
13.
全球大气环流模式BCC_AGCM2.0.1对1998年夏季江淮流域强降水过程的回报试验研究 总被引：5，自引：5，他引：0
利用中国气象局北京气候中心全球大气环流模式(BCC_AGCM2.0.1) 对1998年6月24日～7月3日发生在我国江淮流域的强降水天气过程进行了回报试验。模式起报时间为1998年6月24日00时, 使用前10天NCEP-II再分析逐时温度、涡度和散度场进行预报前初始协调 (spin-up) 积分, 产生模式初值, 预报时段为1998年6月24日～7月10日, 回报试验结果表明: 模式对全球500 hPa位势高度的天气尺度演变过程具有4～7天的可预报性; BCC_AGCM2.0.1模式对中国区域的降水以及大气环流场具有3～4天的可预报性, 6月24日起报后3天内的预报降水区域位置与实况一致, 但中心强度有所差异。对起报后未来2天的5 mm和10 mm以上的降水预报能力相对较强, ETS评分值达到了0.25以上, HK评分超过了0.4, 降水区域范围预报较为准确, BIA评分趋于1.0。模式对20 mm以上的降水也具有一定的可预报性, 但模式对大于30 mm以上强降水的预报能力较差。 相似文献
14.
Evaluation of cloud vertical structure simulated by recent BCC_AGCM versions through comparison with CALIPSO-GOCCP data 总被引：2，自引：0，他引：2
ABSTRACT The abilities of BCC-AGCM2.1 and BCC_AGCM2.2 to simulate the annual-mean cloud vertical structure （CVS） were evaluated through comparison with GCM-Oriented CALIPSO Cloud Product （CALIPSO-GOCCP） data. BCC-AGCM2.2 has a dynamical core and physical processes that are consistent with BCC-AGCM2.1, but has a higher horizontal resolution. Results showed that both BCC-AGCM versions underestimated the global-mean total cloud cover （TCC）, middle cloud cover （MCC） and low cloud cover （LCC）, and that BCC_AGCM2.2 underestimated the global-mean high cloud cover （HCC）. The global-mean cloud cover shows a systematic decrease from BCCA-GCM2.1 to BCC_AGCM2.2, especially for HCC. Geographically, HCC is significantly overestimated in the tropics, particularly by BCC_AGCM2,1, while LCC is generally overestimated over extra-tropical lands, but significantly underestimated over most of the oceans, especially for subtropical marine stratocumulus clouds. The leading EOF modes of CVS were extracted. The BCC_AGCMs perform well in reproducing EOF1, but with a larger variance explained. The two models also capture the basic features of EOF3, except an obvious deficiency in eigen- vector peaks. EOF2 has the largest simulation biases in both position and strength of eigenvector peaks. Furthermore, we investigated the effects of CVS on relative shortwave and longwave cloud radiative forcing （RSCRF and RLCRF）. Both BCC_AGCM versions successfully reproduce the sign of regression coefficients, except for RLCRF in PC1. However, the RSCRF relative contributions from PC1 and PC2 are overestimated, while the relative contribution from PC3 is underes timated in both BCC_AGCM versions. The RLCRF relative contribution is underestimated for PC2 and overestimated for PC3. 相似文献
15.
The subseasonal variability and predictability of the Arctic Oscillation/North Atlantic Oscillation (AO/NAO) is evaluated using a full set of hindcasts generated from the Beijing Climate Center Atmospheric General Circulation Model version 2.2 (BCC_AGCM2.2). It is shown that the predictability of the monthly mean AO/NAO index varies seasonally, with the highest predictability during winter (December–March) and the lowest during autumn (August–November), with respect to both observations and BCC_AGCM2.2 results. As compared with the persistence prediction skill of observations, the model skillfully predicts the monthly mean AO/NAO index with a one-pentad lead time during all winter months, and with a lead time of up to two pentads in December and January. During winter, BCC_AGCM2.2 exhibits an acceptable skill in predicting the daily AO/NAO index of ∼9 days, which is higher than the persistence prediction skill of observations of ∼4 days. Further analysis suggests that improvements in the simulation of storm track activity, synoptic eddy feedback, and troposphere–stratosphere coupling in the Northern Hemisphere could help to improve the prediction skill of subseasonal AO/NAO variability by BCC_AGCM2.2 during winter. In particular, BCC_AGCM2.2 underestimates storm track activity intensity but overestimates troposphere–stratosphere coupling, as compared with observations, thus providing a clue to further improvements in model performance. 相似文献
16.
本文讨论了国家气候中心第二代大气环流模式BCC_AGCM2.0.1和加拿大气溶胶理化模式CAM所组成的耦合模式系统对5种典型气溶胶(硫酸盐、黑碳、有机碳、沙尘和海盐)和气候要素的模拟效果。结果表明,耦合系统对5种典型气溶胶的模拟总体上比较合理,尤其是对硫酸盐、沙尘和海盐的模拟比BCC_AGCM2.0.1原有的月平均气溶胶资料有很大的改进。耦合系统模拟的全球平均气候态参量与观测/再分析资料比较一致,在总云量、陆地表面温度和降水等方面要略优于原月平均气溶胶资料的模拟结果。耦合系统对沙尘和海盐气溶胶模拟的改进使得撒哈拉沙漠和南半球中纬度海洋大气顶净太阳辐射的模拟也有所改进,而这将直接影响地表温度尤其是陆地表面温度。而不同气溶胶方案在赤道海洋上引起的云反馈不仅引起辐射的改变,还将对降水产生明显影响。 相似文献