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1996 Vol. 13, No. 3

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Description of A Nine-Level Grid Point Atmospheric General Circulation Model
Liang Xinzhong
1996, 13(3): 269-298. doi: 10.1007/BF02656847
A brief description of a nine-level grid-point global atmospheric general circulation model is presented with the emphasis on the physics parameterizations. This model was developed by the modeling group from Institute of At-mospheric Physics as one task of the CO2-Climate cooperation project between Chinese Academy of Sciences and United States Department of Energy. The task was initiated by Qing-Cun Zeng (IAP) and Robert D. Cess (SUNY). The operational design, computer coding and climate simulation tuning of the model were mainly carried out by Xue-Hong Zhang (for dynamics) and the author (for physics) in SUNY at Stony Brook. The final version was frozen in September 1990. Preliminary diagnose showed that the model reproduces principal features of the observed climatology.
Bivariate Wavelet Analysis of Asia Monsoon and ENSO
Lonnie Hudgins, Jianping Huang
1996, 13(3): 299-312. doi: 10.1007/BF02656848
This paper employs some recently developed bivariate wavelet analysis techniques to study the correlation be-tween Asia monsoon and El Nino southern oscillation (ENSO). Various energy spectral densities are defined for wavelet transforms, analogous to those used in conventional Fourier analysis. Some comparisons are made by ap-plying both wavelet and Fourier spectral methods to the data. The wavelet analysis shows evidence of some relation-ship between Asia monsoon and ENSO, which the Fourier analysis resolves poorly. Correlation on several time scales, ranging from 2-4 years, 11 years, and 22 years, become apparent with the wavelet cross-spectrum. Finally, the wavelet cross-transform provides time localization of the distinctive features within the data record.
A Sensitivity Study of Single Column Model
Min Dong, Qin Xu
1996, 13(3): 313-324. doi: 10.1007/BF02656849
A single column model (SCM) is constructed by extracting the phytical subroutine from the NCAR Community Climate Model version 1 (CCM1). Simulated data are generated by CCM1 and used to validate the SCM and to study the sensitivity of the SCM to errors in its input data. It is found that the SCM temperature predictions ire mod-erately sensitive to errors in the input horizontal temperature flux convergence and moisture flux convergence. Two types of error are concerned in this study: random errors due to insufficient data resolution, and errors due to insufficient data area coverage. While the first type of error can be reduced by filtering and / or increasing the data resolution, it is shown that the second type of error can be reduced by enlarging the data area coverage and using a suitable method to compute the input flux convergence terms.
Characteristics of Soliton with Dynamic Constraints on its Existence / Propagation in Tropical Easterly Wave
Zhang Ren
1996, 13(3): 325-339. doi: 10.1007/BF02656850
The study concerns the propagation of easterly wave (EW) at tropics as west-moving soliton more steady both in form and velocity as evidenced in the dynamic framework. Under the impact of different circulation patterns over the regions of western Pacific trade wind, South-Asia monsoon and their transition, such a soliton becomes tapering off during its westward movement and degrading to a common dispersive wave on the whole, followed by disintegra-tion when striking the South-China Sea monsoon segment, thereby indicating that the sea sector is inaccessible to the soliton. When no monsoon trough is present over the South Asian monsoon area around 30oN or the monsoon de-pression is shallow, it is likely to have west-travelling soliton, which suggests the incursion of the EW into the South-Asian monsoon region.
Calculation of Ice Crystal Diffraction
Liu Chunlei, Yao Keya
1996, 13(3): 340-348. doi: 10.1007/BF02656851
The diffraction angular distributions are calculated for different ice crystals (e. g. solid and hollow hexagonal columns, solid plates and single hexagonal bullet) randomly oriented in space, based on the theory of Cai and Liou. Results of solid column and plate are compared with these from formulas of Wendling et al. and Liou. The result comparison shows that all three procedures discussed in this paper have good agreement. After considering the com-putation time and comparison results, it is suggested that the formula of Wendling et al. can be used to calculate the solid column diffraction, and the formula of Liou can be used to calculate the plate diffraction. The comparison also shows that the diffraction results of solid column, hollow column and single bullet ice particles randomly oriented in space are very close.
Estimation of Hourly and Daily Global Solar Radiation at Clear Days Using an Approach Based on Modified Version of Gaussian Distribution
S. M. El shazly
1996, 13(3): 349-358. doi: 10.1007/BF02656852
The performance of two models, Jain and Baig, based on the modified version of Gaussian distribution function in estimating the daily total of global solar radiation and its distribution through the hours of the day from sunrise to sunset at any clear day is evaluated with our own measured data in the period from June 1992 to May 1993 in Qena / Egypt. The results show a high relative deviation of calculated values from measured ones, especially for Jain model, in the most hours of the day, except for those near to local noon. This misfit behavior is quite obvious in the early morning and late afternoon. A new approach has been proposed in this paper to estimate the daily and hourly global solar radiation. This model performs with very high accuracy on the recorded data in our region. The validity of this approach was verified with new measurements in some clear days in June and August 1994. The resultant very low relative deviation of the calculated values of global solar radiation from the measured ones confirms the high per-formance of the approach proposed in this work.
Observations of NO2 and O3 during Thunderstorm Activity Using Visible Spectroscopy
D.B. Jadhav, A.L. Londhe, S. Bose
1996, 13(3): 359-374. doi: 10.1007/BF02656853
Simultaneous observations for the total column densities of NO2, O3 and H2O were carried on using the porta-ble Spectrometer (438-450 nm and 400-450 nm) and the visible Spectrometer (544.4-628 nm) during premonsoon thunderstorms and embedded hail storm activity at Pune (18o32’N & 73o51’E), India. These observations confirm the fact that there is an increase in O3 and NO2 column densities during thunderstorms. The increase in O3 was observed following onset of thunderstorm, while the increase in NO2 was observed only after the thunder flashes occur. This implies that the production mechanisms for O3 and NO2 in thunderstorm are different. The observed column density of NO2 value (1 to 3 × 1017molecules · cm-2) during thunderstorm activity is 10 to 30 times higher than the value (1 × 1016molecules · cm-2) of a normal day total column density. The spectrometric observations and observations of thunder flashes by electric field meter showed that 6.4 × 1025molecules / flash of NO2 are produced. The increased to-tal column density of ozone during thunderstorm period is 1.2 times higher than normal (clear) day ozone concentra-tion. The multiple scattering in the clouds is estimated from H2O and O2 absorption bands in the visible spectral re-gion. Considering this effect the calculated amount of ozone added in the global atmosphere due to thunderstorm ac-tivity is 0.26 to 0.52 DU, and the annual production of ozone due to thunderstorm activity is of the order of 4.02 × 1037 molecules /year. The annual NO2 production may be of the order of 2.02 × 1035molecules / year.
Spatial / Temporal Features of Antarctic Climate Change
Ge Ling, Liang Jiaxing, Chen Yiliang
1996, 13(3): 375-382. doi: 10.1007/BF02656854
Based on January 1962-October 1993 mean value series of monthly mean temperature anomalies of 16 Antarctic stations on 10 standard isobaric surfaces from the surface to the 30 hPa, long term trends and periodic features of climate changes from the troposphere to the lower stratosphere over the Antarctic region are investigated by maxi-mum entropy power spectrum analysis, and the relation between climate change of the stratosphere (troposphere) and total ozone (southern 500 hPa circulation) is discussed.
Numerical Modelings of the Climatic Effects of the Land-Sea Distribution and Topography
Qian Yongfu, Wang Qianqian
1996, 13(3): 383-398. doi: 10.1007/BF02656855
The effects of the land-sea contrast and the topography on the climatic properties are simulated in this paper by use of a p- σ incorporated coordinate system model in a zonal domain. In this paper we firstly discuss the statistical features of the model and find that the capability of the model is stable, with the same land-sea distribution and to-pography seven monthly mean climate states are close to one another, their variance is even less than the initial one. Secondly, we focally discuss the effects of the land-sea contrast and the topography on the modeled climate fields, It is pointed out that the land-sea contrast and the topography influence the atmosphere mainly through the heating ef-fect and the former has larger influences on the simulated large scale climate fields than the latter.
Sulfur Distribution and Transport Studies in East Asia Using Eulerian Model
Wang Zifa, Huang Meiyuan, He Dongyang, Xu Huaying, Zhou Ling
1996, 13(3): 399-409. doi: 10.1007/BF02656856
A three-dimensional regional Eulerian model of sulfur deposition and transport is developed. Processes treated in the model include emission, transport, diffusion, gas-phase and aqueous-phase chemical process, dry deposition, rainout and washout or sulfur. A “looking up table” method is provided to deal with the gas-phase chemical process including sulfur transfer. Dry-depositon velocity considers the influence of underlying surface, wind, degree of stabil-ity by parameterization. Model calculated values reasonably agrees with observation. Distribution of sulfur deposi-tion and transport in East Asia are also analyzed in this paper. Some amount of sulfur emission of different countries transport across boundaries, but the main origin of sulfur deposition in each country in East Asia is from itself. Furthermore, some transport paths on different layers and outlet or inlet zones are found. According to sulfur bal?ance and budget we concluded that sulfur outlets are bigger than inlets across boundary and emissions are more than deposition in most places of East Asia.