Abstract
The commonly used objective analysis scheme (Scheme-A) for the analysis of wind and geopotential height smoothen the divergent component of the wind which is rather important in the tropics, specifically over convective regions. To overcome this deficiency, a new analysis scheme in which divergent component is included in the statisti-cal model of the wind forecast errors, has been proposed by Daley (1985). Following this scheme, a new set of correla-tion functions of forecast errors for the Indian region during monsoon season which are suitable for analysing the tropical wind are obtained. This analysis scheme (Scheme-B) as well as Scheme-A were used to make analyses for the period from 4 July to 8 July 1979 (12 GMT) at 850, 700 and 200 hPa levels over an area bounded by 1.875°N to 39.375°N and 41.250°E to 108.750°E and subsequently divergent component, velocity potential are computed for both schemes. Results from both these schemes show that in the monsoon depression region the velocity potential and divergence have increased in the later case (Scheme-B). This suggests that the divergent component has been en-hanced in Scheme-B and that the objective of this study is realized to some extent.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bergman, K. H. (1979), Multivariate analysis of temperature and winds using optimum interpolation,Mon. Wea. Rev.,107: 1423–1444.
Daley, R. (1983), Spectral characteristic of the ECMWF objective analysis system, ECMWFTech. Rep. No 40: pp. 117.
Daley, R. (1985), The analysis of synoptic scale divergence by a statistical interpolation procedure,Mon. Wea. Rev.,113: 1066–1079.
Gandin, L. S. (1963), Objective analysis of meteorological fields,Gidrometeoizdat, Leningrad (Israeli Programme for Scientific Translations 1965, pp. 242).
Hollingsworth, A and Lonnberg, P. (1986), The statistical structure of short range forecast errors as determined from radiosonde data. Part I: The wind field,Tellus,38A: 111–136.
Julian, P. R (1984), Objective analysis in the Tropics: A proposed scheme,Mon. Wea. Rev.,112: 1752–1767.
Kasahara, A. et al. (1988), Use of satellite radiometric imagery data for improvement in the analysis of divergent wind in the tropics,Mon. Wea. Rev.,116: 866–883.
Krishnamurti, T. N. (1971), Tropical east-west circulation during the northern summer,Jour. Atmos. Scien.,28: 1342–1347.
Matsuno, T. (1966), Quasi-Geostrophic motion in equatorial area,Jour. Met. Soc. of Japan,44: 25–43.
Schlatter, T. W (1975), Some experiments with a multivariate statistical objective analysis scheme,Mon. Wea. Rev.,103: 246–257.
Seaman, R. and Gauntlett, D. (1980), Directional dependence of zonal and meridional wind correlation coefficients,Aust. Met. Mag.,28: 217–221.
Sinha, S. K. et al. (1992), Some experiments with multivariate objective analysis scheme of height and winds using optimum interpolation,Adv. Atom. Sci.,9: 431–440.
Tandon, M. K. (1992), A FORTRAN algorithm for divergent and rotational wind fields, HTMRes. Rep. No.RR–052: 1–36.
Unden, P. (1989), Tropical data assimilation and analysis of divergence,Mon. Wea. Rev.,117: 2495–2517.
Xue, Jishan and Wang, K. (1992), Objective analysis of wind and pressure fields in the tropics,Chinese Journal of Atmospheric Sciences,16: 179–188.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Sinha, S.K., Narkhedkar, S.G. & Rajamani, S. Multivariate objective analysis of wind and height fields in the tropics. Adv. Atmos. Sci. 12, 233–244 (1995). https://doi.org/10.1007/BF02656836
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF02656836