共查询到20条相似文献，搜索用时 31 毫秒
1.
3.
4.
Wind-Driven, Double-Gyre, Ocean Circulation in a Reduced-Gravity, 2.5-Layer, Lattice Boltzmann Model
A coupled lattice Boltzmann （LB） model with second-order accuracy is applied to the reduced-gravity, shallow water, 2.5-layer model for wind-driven double-gyre ocean circulation. By introducing the secondorder integral approximation for the collision operator, the model becomes fully explicit. The Coriolis force and other external forces are included in the model with second-order accuracy, which is consistent with the discretization accuracy of the LB equation. The feature of the multiple equilibria solutions is found in the numerical experiments under different Reynolds numbers based on this LB scheme. With the Reynolds number increasing from 3000 to 4000, the solution of this model is destabilized from the anti-symmetric double-gyre solution to the subtropic gyre solution and then to the subpolar gyre solution. The transitions between these equilibria states are also found in some parameter ranges. The time-dependent variability of the circulation based on this LB simulation is also discussed for varying viscosity regimes. The flow of this model exhibits oscillations with different timescales varying from subannual to interannual. The corresponding statistical oscillation modes are obtained by spectral analysis. By analyzing the spatiotemporal structures of these modes, it is found that the subannual oscillation with a 9-month period originates from the barotropic Rossby basin mode, and the interarmual oscillations with periods ranging from 1.5 years to 4.6 years originate from the recirculation gyre modes, which include the barotropic and the baroclinic recirculation gyre modes. 相似文献
5.
6.
作物布局,耕作制度,栽培技术与棉铃虫调控 总被引：1，自引：0，他引：1
分析了８０年代以来作物布局、耕作制度、栽培技术的变化,指出这些变化与棉铃虫为害有着密切的关系,从这一角度提出了调控棉铃虫的措施。 相似文献
7.
8.
9.
10.
Empirical equations relating runoff,maximum river stageand peak flow to rainfall were developed for the Tao riverdrainage basin at Li Jia Cun.A basin recession curve wasderived and a frequency analysis of extreme flood events wasconducted.Results showed that storm runoff was highlycorrelated with rainfall.However,maximum river stage andpeak flow were not as well correlated with rainfall.It wasfound necessary to separate rainfall into stratiform andconvective types.The magnitudes of the once-in-50 year,once-in-100 year and once-in-200 year events,calculated by thelog Pearson type Ⅲ distribution were closely equal to thoseestimated from a log-probability graph.Recommendations forimproving the predictive ability of the empirical equations arepresented. 相似文献
11.
Gao Feng Chen Xiaoling Yang Wenfu Wang Wenwen Shi Lijiang Zhang Xiaolong Liu Yaomeng Tian Yaofei 《Theoretical and Applied Climatology》2022,148(3-4):955-966
Theoretical and Applied Climatology - Under the background of global warming, an analysis of the trend and variability of rainfall time series on various timescales is very important for... 相似文献
12.
陆帼英 《沙漠与绿洲气象(新疆气象)》1996,19(5):48-51
新疆是我国第二大牧区，重要的畜牧业生产基地。畜牧业生产在自治区国瓦经济中占有重要的地位。几十年来，自治区的畜牧业有了很大的发展，但由于牧区生产、改造需要的投入较大，目前的基础设施仍较薄弱，生产方式落后，经营单一、粗放，效益低下。新疆气象业务中心（气象台）一直把对牧区的防灾减灾工作作为一项重要的政治任务，一项重要的为大农业服务的任务来认真组织，热情服务。40余年来通过科学研究、技术开发和服务实践，我们逐步认识了牧区防灾减灾的客观规律，把牧区防灾减灾服务从转场服务为主转变为以预防为主、防治结合的监测、… 相似文献
13.
14.
15.
16.
17.
《沙漠与绿洲气象(新疆气象)》1988,(12)
乌鲁木齐县砖厂位于四平路,建于1970年9月,1980年开始了大批量的生产,固定资产原值250万元,净值174万元,年设计能力有红砖5000万块,实际能力达4000万块;产品项目有红砖、空心砖、水泥预制构件、铺路基的道砸石、珍珠岩保温瓦、制鞋等六种, 相似文献
18.
A photochemical scheme which includes a detailed treatment of multiple scattering up to solar zenith angles of 96° (developed for use in a GCM) has been used to study partitioning within chemical families. Attention is drawn to the different zenith angle dependence of diffuse radiation for the two spectral regions <310 nm and >310 nm. The effect that this has on the so-called 40 km ozone problem is discussed. The importance of correctly including multiple scattering for polar ozone studies is emphasised. 相似文献
19.