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1.
The INMCM5.0 numerical model of the Earth’s climate system is presented, which is an evolution from the previous version, INMCM4.0. A higher vertical resolution for the stratosphere is applied in the atmospheric block. Also, we raised the upper boundary of the calculating area, added the aerosol block, modified parameterization of clouds and condensation, and increased the horizontal resolution in the ocean block. The program implementation of the model was also updated. We consider the simulation of the current climate using the new version of the model. Attention is focused on reducing systematic errors as compared to the previous version, reproducing phenomena that could not be simulated correctly in the previous version, and modeling the problems that remain unresolved.  相似文献   

2.
李响  吴辉碇  王辉 《海洋通报》2011,30(2):180-186
由于海上大气边界层的下垫面是复杂多变的海面,因此海面状态的参数化对海上大气边界层数值模拟起到十分关键的作用.采用高分辨率的大气边界层模式进行敏感性试验研究,讨论了不同海面参数化方案对海上大气边界层数值模拟产生的影响.结果表明:几种海面粗糙度参数化方案在中低风速下模拟垂直结构主要的差异出现在边界层和自由大气分界面上;考虑...  相似文献   

3.
Results of simulating the diurnal evolution of the atmospheric boundary layer (ABL) with a second-order closure model are presented. The model includes new algebraic expressions for triple correlations to describe their behavior over the entire height of the mixed layer adequately to measurements. The model also takes into account the influence of long-wave radiation on the heat balance, which becomes important in the nocturnal ABL. The modeling results are compared with 24-h ABL evolution simulations by the third-order closure model and available in situ and laboratory measurements.  相似文献   

4.
The INMCM3.0 climate model has formed the basis for the development of a new climate-model version: the INMCM4.0. It differs from the previous version in that there is an increase in its spatial resolution and some changes in the formulation of coupled atmosphere-ocean general circulation models. A numerical experiment was conducted on the basis of this new version to simulate the present-day climate. The model data were compared with observational data and the INMCM3.0 model data. It is shown that the new model adequately reproduces the most significant features of the observed atmospheric and oceanic climate. This new model is ready to participate in the Coupled Model Intercomparison Project Phase 5 (CMIP5), the results of which are to be used in preparing the fifth assessment report of the Intergovernmental Panel on Climate Change (IPCC).  相似文献   

5.
通过中尺度气象研究与预报模式WRF(weather research and forecasting)和两种台风经验模型重构了2018年影响我国珠江口地区的超强台风“山竹”过程中的气压和风矢量场,在台风最佳路径数据的基础上开展了方法间的比较,并与香港、澳门和深圳三个国际机场的实测数据进行了对比分析,验证了三种模拟方案模拟台风“山竹”的可靠性。利用非结构网格半隐式跨尺度海洋模式SCHISM (semi-implicit cross-scale hydroscience integrated system model),将三种模拟气压和风场作为驱动场输入风暴潮模式中进行增水模拟试验,比较了它们在赤湾、三灶、横门和黄埔四个测站风暴潮增水中各自的效果,并进一步验证了WRF模式和两种经验模型模拟台风“山竹”的有效性。综合来看, WRF大气模式对气压、风速、风向及风暴增水模拟效果最佳,如果进一步优化该模式的各种参数化方案,可能还能提高其精度。如果不具备使用WRF大气模式的条件,台风经验1模型也是一个完全可以接受的、简单快捷的方案。  相似文献   

6.
This paper considers the formation of the thermohaline structure of the Arctic Ocean: the formation of the salinity field and a freshwater reservoir in the Beaufort Sea and the transport of warm Atlantic water into the central part of the Arctic Ocean. A new version of the Finite Element Model of the Arctic Ocean (FEMAO) with a low spatial resolution is used. The main distinctions of this version are the following features: a new equation of state, a more sophisticated parameterization of vertical turbulence, modified formulations for the boundary conditions on open boundaries (using satellite data on the sea level) and at the upper boundary of the ocean, and the use of a variable eddy diffusivity in the parameterization of the eddy transport of a scalar. Our experiments indicated that the use of the parameterization of the eddy transport of a scalar enhances the transport of warm Atlantic waters to the central part of the Arctic Ocean through the Fram Strait; the results are most realistic when a variable coefficient is used. The Neptune effect has a contradictory role and, in the future, a higher spatial resolution should be used instead of this parameterization. We revealed that a key factor in the thermohaline fields on a large time scale is the interaction with the Atlantic Ocean, which is the source of heat and saline water.  相似文献   

7.
The work describes the creation of a new global climatology of short-wave radiation incoming to the ocean surface; the climatology is based on a new parameterization of short-wave fluxes. Advantages of the new parameterization are allowance for nonlinearity of the dependence of the atmospheric transmission factor on the height of the Sun under a clear sky and allowance for different morphological types of clouds under the overcast. It is shown that taking into account these factors leads to substantial differences in short-wave radiation fluxes in comparison to existing parameterizations.  相似文献   

8.
This paper reports a case study of atmospheric stability effect on dimethyl sulfide(DMS) concentration in the air. Investigation includes model simulation and field measurements over the Pacific Ocean. DMS concentration in surface sea water and in the air were measured during a research cruise from Hawaii to Tahiti. The diurnal variation of air temperature over the sea surface differed from the diurnal cycle of sea surface temperature because of the high heat capacity of sea water. The diurnal cycle of average DMS concentration in the air was studied in relation to the atmospheric stability parameter and surface heat flux. All these parameters had minima at noon and maxima in the early morning. The correlation coefficient of the air DMS concentration with wind speed (at 15 m high) was 0. 64. The observed concentrations of DMS in the equatorial marine surface layer and their diurnal variability agree well with model simulations. The simulated results indicate that the amplitude of the cycle and the mean  相似文献   

9.
基于一个一维湍能海洋混合层模式,发展了一个易于与大气或海洋模式耦合的,可应用于水平二维空间的模块化海洋混合层模式。并加入垂直上翻参数化方案,引入日平均海面温度及气候态松弛项,进行二维海洋模拟理想气旋实验和飓风实例模拟实验。理想气旋强迫实验表明,垂直上翻过程的参数化方案可有效地弥补原有一维海洋混合层模式无法形成气旋中心动力上翻的不足,消除了虚假暖水核心。卡特里娜飓风个例实验的结果表明,加入垂直上翻后,飓风中心附近的海表面温度误差明显减小。海洋混合层模式对海洋表面温度日变化模拟能力在二维应用中依然表现良好。经过上述改进,发展的海洋混合层模式可以较为真实地模拟平常海表温度高频日变化的同时,还对剧烈天气过程也有一定的模拟能力,具有广泛的应用前景。  相似文献   

10.
A new version of the Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS), climate model (CM) has been developed using an ocean general circulation model instead of the statistical-dynamical ocean model applied in the previous version. The spatial resolution of the new ocean model is 3° in latitude and 5° in longitude, with 25 unevenly spaced vertical levels. In the previous version of the oceanic model, as in the atmospheric model, the horizontal resolution was 4.5° in latitude and 6° in longitude, with four vertical levels (the upper quasi-homogeneous layer, seasonal thermocline, abyssal ocean, and bottom friction layer). There is no correction for the heat and momentum fluxes between the atmosphere and ocean in the new version of the IAP RAS CM. Numerical experiments with the IAP RAS CM have been performed under current initial and boundary conditions, as well as with an increasing concentration of atmospheric carbon dioxide. The main simulated atmospheric and oceanic fields agree quite well with observational data. The new version’s equilibrium temperature sensitivity to atmospheric CO2 doubling was found to be 2.9 K. This value lies in the mid-range of estimates (2–4.5 K) obtained from simulations with state-of-the-art models of different complexities.  相似文献   

11.
This paper formulates the most general principles for verifying models of the dynamic near-water layer of the atmosphere (DNWLA) and performs an advanced verification of the model proposed by the author earlier [6]. Based on empirical wave spectra from the studies by Donelan [15], Elfouhaily [14], and Kudryavtsev [13] and well-known empirical laws describing the wave-age dependence of the friction coefficient, we adjusted the original version of the model. It was shown that the improvement of model reliability is most dependent on the adequacy of the parameterization of the tangential portion of the total momentum flux to the wavy surface. Then the new version of the model was verified on the basis of field data from two different groups of authors. It was found that the new version of the model is consistent with empirical data with an error not exceeding the measurement error of near-water layer parameters.  相似文献   

12.
《Oceanologica Acta》1998,21(3):393-417
Available climatic and atmospheric analysis data have been used to prepare forcing functions for the Black Sea numerical model, based on the Bryan-Semtner-Cox Modular Ocean Model and including parameterizations for the atmosphere-ocean exchange, inflow through the strait of Bosphorus and the Mediterranean plume. Atmospheric data from different sources are compared and the drawbacks of some of them illustrated. A new wind stress data set, based on ship observations, is prepared. Compared to the existing wind stress estimates, the present ones use additional data and more accurate parameterization of the boundary layer physics. The intercomparison between forcing data sets is focused on the heat flux and freshwater flux at the sea surface.The model simulates adequately vertical stratification, seasonal variability and horizontal patterns. Five data sets for heat flux, freshwater flux and wind stress are used in different combinations to study the model response. The large differences between the simulations, forced by different wind stress and identical thermohaline forcing, justify the computation of the new wind stress. Though the forcing data used are perhaps close to the best available at the moment for the Black Sea, the model simulations range in large intervals and some of them are very poor. The model responses to forcing functions of different origin give rough estimates on the possible errors in present-day simulations. Some inconsistencies give clear indications that further verifications, improvements of the forcing functions, and intercomparisons between the responses simulated by the ocean circulation models are needed.  相似文献   

13.
The effects of atmospheric nitrogen input on biological production in the Japan Sea have been investigated using a coupled physical-ecosystem model. Comparison between the cases with and without nitrogen deposition shows a relatively large effect on primary production in the southern Japan Sea during summer to autumn, when nitrogen deposition is high and nutrient is depleted in the surface layer. The atmospheric nitrogen deposition supports > 10% of the annual export production in the nearshore region along the Japanese coast. The importance of atmospheric input as a new nutrient will grow steadily with increasing deposition into the Japan Sea.  相似文献   

14.
在海-气相互作用研究中,大气下行辐射的准确估算具有重要意义。在气象站点分布密集的地区,大气下行辐射可通过常规的仪器测量获取。但海洋表面布点成本高,维护比较困难,严重影响我们对海区辐射特征的认识和了解。遥感可提供良好的时空连续性和多层次数据,是研究大气下行辐射的有效手段。本文模拟了不同大气条件下海表的长波下行辐射,考虑到大气下行辐射不仅与所在层的大气有关,还受临近大气层的影响,我们通过增加大气水汽含量重新参数化大气比辐射率,改进Brutsaert模型,建立基于MODIS数据遥感估算海洋表面大气下行辐射的模型,并利用"中国近海海洋综合调查与评价"项目中黄海区观测的海-气通量观测资料对所提出的模型进行检验。结果表明,本文所改进的参数化模型在模拟数据中的均方误差(RMSE)为11.2 W/m~2;在实际数据验证中,RMSE为20.9 W/m~2;模型的精度基本达到了海-气作用研究中对瞬时大气下行辐射的精度要求。  相似文献   

15.
A two-dimensional non-hydrostatic ocean model and a hydrostatic version of the same model are used to simulate convective adjustment, without the use of an instantaneous adjustment parameterization. The model geometry is a domain on the vertical plane of width 40 km and depth 500 m. Model results for four cases are examined: hydrostatic and non-hydrostatic, at 0.1 and 1 km spatial resolution. The convectively adjusted stable state obtained in all four cases are qualitatively similar; thus the hydrostatic approximation does not eliminate convective adjustment. The details of the simulated convective plumes depend on resolution and whether the hydrostatic approximation is made. The adjusted state has significant stratification which cannot be captured by the conventional instantaneous adjustment or diffusion-based parameterizations. We also compare the results to the case when an instantaneous adjustment parameterization is used.  相似文献   

16.
The performance of the “version 2” Global Imager (GLI) standard atmospheric correction algorithm, which includes empirical absorptive aerosol correction and sun glint correction, was evaluated using data collected with handheld above-water SIMBADA radiometers during 23 cruises of opportunity (research vessels, merchant ships), mostly in the North Atlantic and European seas. A number of 100 match-up data sets of GLI-derived and SIMBADA-measured normalized water-leaving radiance (nL W ) and aerosol optical thickness (AOT) were sorted out, using objective selection criteria, and analyzed. The Root-Mean-Square (RMS) difference between GLI and SIMBADA nL W was about 0.32 μW/cm2/nm/sr for the 412 nm band, showing improvement by 30% in RMS difference with respect to the conventional “version 1” GLI atmospheric correction algorithm, and the mean difference (or bias) was reduced significantly. For AOT, the RMS difference was 0.1 between GLI estimates and SIMBADA measurements and the bias was small (a few 0.01), but the ?ngstr?m exponent was systematically underestimated, by 0.4 on average, suggesting a potential GLI calibration offset in the near infrared. The nL W differences were not correlated to AOT, although performance was best in very clear conditions (AOT less than 0.05 in the 865 nm band). Despite the relatively large scatter between estimated and measured nL W , the derived chlorophyll-a concentration estimates, applying the same ratio algorithm (GLI OC4V4) to GLI and SIMBADA, were consistent and highly correlated in the range of 0.05–2 μg/l. The large variability in chlorophyll-a concentration estimate for clear clean water areas (e.g. with the concentration range lower than about 0.05 μg/l) turns out to be due to the nature of the “band ratio” based in-water algorithm.  相似文献   

17.
Surface waves are the roughness element of the ocean surface, the air-sea interaction processes are influenced by the wave conditions. The dynamic influence of surface waves decays exponentially with distance from the air-water interface. The relevant length scale characterizing the decay rate is the wavelength. The parameterization of drag coefficient and surface roughness can be significantly improved by using wavelength as the reference length scale of atmospheric measurements. The wavelength scaling of drag coefficient and dynamic roughness also receives support from theoretical studies of wind and wave coupling.  相似文献   

18.
基于POLDER多角度观测数据,对其大气校正算法进行了研究。该大气校正算法中,大气分子散射利用多次散射加偏振的精确瑞利散射来计算,同时,对太阳耀斑及白帽散射进行了校正。由本文大气校正算法可以反演得到气溶胶光学厚度以及海水反射率,与POLDER二级产品相比表明,利用该算法反演所得产品效果较好,相对误差在10%左右,从而为未来中国多角度水色遥感的发展提供一些参考。  相似文献   

19.
The Global Lagrangian Atmospheric Dispersion Model (GLADIM) is described. GLADIM is based on the global trajectory model, which had been developed earlier and uses fields of weather parameters from different atmospheric reanalysis centers for calculations of trajectories of air mass that include trace gases. GLADIM includes the parameterization of turbulent diffusion and allows the forward calculation of concentrations of atmospheric tracers at nodes of a global regular grid when a source is specified. Thus, GLADIM can be used for the forward simulation of pollutant propagation (volcanic ash, radionuclides, and so on). Working in the reverse direction, GLADIM allows the detection of remote sources that mainly contribute to the tracer concentration at an observation point. This property of Lagrangian models is widely used for data analysis and the reverse modeling of emission sources of a pollutant specified. In this work we describe the model and some results of its validation through a comparison with results of a similar model and observation data.  相似文献   

20.
The theory of both time-and space-dependent empirical orthogonal functions (EOFs) is outlined from a common point of view as a discrete version of the Karhunen-Loeve expansion. EOF techniques are used to process the results of a 1300-day-long numerical experiment in the mode of perpetual January with a daily step. As a result, the component determined by internal hydrothermodynamic processes was isolated from the general variability of the atmospheric circulation. To isolate intraseasonal variability (a winter season), the principal components of the 500-hPa height field were processed with a filter close to a π-shaped filter isolating the frequency band 0.1–0.01 day?1. The spatial principal components were analyzed via the method of time-dependent EOFs. The spectral characteristics obtained can characterize the intraseasonal low-frequency variability and agree partially with empirical data.  相似文献   

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