Long Term Variations of Ionospheric Horizontal Drift and Anisotropy of E-region Irregularities at Waltair

Appa Rao Vegi, Jogulu Challa, Suryanarayana M. B

Abstract


The study of long term variation of drift and anisotropy parameters of E region irregularities is particularly important because of the fact that D1 method measures movements of ionization that corresponds with neutral air motion in this region and facilitates a comparison with other methods of measuring winds in this region. The study of horizontal movements of small scale ionospheric irregularities at Waltair (17.70 N; 83.30 E) using D1 technique was started as early as I.G.Y.period. In this paper we present the results of observations of the drift and anisotropy parameters of ionospheric irregularities during equinox season over a span of about 10 years from 1957 to 1966 covering both the I.G.Y.and I.Q.S.Y.periods.About 140 midday (10-14 hrs) E-region drift records taken on frequency of 2.4 MHz are selected for the present study. There is an overall increase observed in the velocity parameters Va, V and Vc with the increase of sunspot number. The structure size, a of the irregularities shows a negative variation with sunspot number, decreasing magnitude with increase in sunspot number. There seem to be seasonal variation in the long term variation of some of the drift parameters with respect to solar epoch at Waltair.             


Keywords


Close spaced receivers; Ground diffraction pattern; Ionospheric irregularities; Sunspot number.

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References


.Briggs, B.H. (1960).”Monograph on Ionospheric Radio”. Thirteenth General Assembly. URSI, 219.

.Morris, R.W. & Lyon, A.T. (1966).Nature. 210,617.

. Sprenger, K. & Schminder, R. (1967). J.Atmos.Terr.Phys. 29, 183.

.Pozigum, V.L. (1968).Geomag.Aeronomy. 8,365.

. Rastogi, R.G. (1969).J.Inst.Telecom.engr., India. 15,216.

. Rastogi, R.G. Chandra, H & M.R.Deshpande. (1970).”Drift and anisotropy parameters of the Irregularities in the E and F- regions of ionosphere over Thumba during 1964”. J.Atmos.Terr.Phys.32, Pp.999-1006.

. Kazimirovsky, E.S. (1972).Phil.Trans.Roy.Soc.Lond.A.271, 499.

. Onalaja, G.B. & Oyinloye, J.O.(1977). J.Atmos.Terr.Phys.39, 1353.

. Patel, V.P. & Chandra H. (1982).” Ionospheric E-region drifts at Sibizmir during 1970-75”. Ind.J.Radio Space phys. 2, pp.187-189.

. Sardesai, D.V.Ph.D, thesis, Sukhadia University, Udaipur, India, 1983.

. Fejer, B.G. (1981).J.Atmos.Terr.Phys. 43, 377.

. Rai, R.K. & Sandhya.in proc.National Space Sci.Symposium (NSSS-90), Nagpur, India.1990.

. Jogulu, C. Ph.D.thesis, Andhra University, Waltair, India, 1968

. Sastri, J.H. Ph.D.thesis, Andhra University, Waltair, India, 1970.

. Mittilesh, M. Chandra and Sharma, P.K. (.2015).”Study of ionospheric drift and anisotropy of E- region irregularities at Udaipur during low and high solar activity periods”. International Journal of Scientific Research in physics and Applied Sciences.3 (1), pp. 34-39.

. Briggs, B.H.Phillips, G.J and Shinn, D.H. “A Study of the Horizontal Irregularities of the Ionosphere”, in .Proc.Phys.Soc. 63 B, 1950,106.

.Phillips, G.J and Spencer, M.in Proc.Phys.Soc, 1955. 68, 481.

.Wiewall, M.Jr. (1962).”Study of ionospheric winds. Additional data on the Determination of the Ionospheric drifts and turbulence from radio fading records”.Scintific report no.6, Defence technical Information centre, mil.

. Yerg, D.G. (1956). J.Atmos.Terr.Phys. 8,247.

. Ramana, K.V.V. Ph.D.thesis, Andhra University, Waltair, India, 1960.

. Millman, G.H.Penn. State Univ.Rep. No.37, 1952.

. Mitra, S.N, in Proc.Inst.Electr.Engrs, 1949, 96, Pt.III, 505.

.Bowhill, S.A.”Direct aeronomic measurements in the lower ionosphere-An informal conference Record”, University of Illinois, Urbana, Illinois, 1963.

.Bowhill, S.A. (1956).J.Atmos.Terr.Phys.8, 129.

. Rastogi, R.G.Chandra, H. & Misra, R.K. (1971).Nature.223, 13.


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