References

ANGEO

Annales Geophysicae

ANGEO

Ann. Geophys.

1432-0576

Copernicus Publications

Göttingen, Germany

10.5194/angeo-30-983-2012

Spectral characteristics and scatter cross-section of low latitude mesospheric echoes measured by the Indian MST radar at Gadanki

Belova

¹ Kirkwood

¹ Narayana Rao

² Satheesh Kumar

² Sergienko

Swedish Institute of Space Physics, Kiruna, Sweden

National Atmospheric Research Laboratory, Gadanki, India

27 06 2012

30 6 983 990

2012

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://angeo.copernicus.org/articles/30/983/2012/angeo-30-983-2012.html

The full text article is available as a PDF file from https://angeo.copernicus.org/articles/30/983/2012/angeo-30-983-2012.pdf

In November 2008 and in March and April 2009 the Indian MST radar (53 MHz) at Gadanki was operated during the daytime in a special experiment, with 600 m altitude resolution, for understanding the characteristics of low-latitude mesospheric echoes (LLME). The data of three days when the echoes were strongest have been analysed in terms of spectral widths and radar volume reflectivities. Spectral widths of LLME show some decrease with altitude, with median values of 4–6 m s−1 at 69–72 km and of 2–4 m s−1 at 73–78 km. This corresponds to 20–200 mW kg−1 turbulent energy dissipation rates. It has been shown that stronger echoes have broader spectra consistent with a turbulent scattering mechanism. For the first time, the volume reflectivities for the strong LLME for Gadanki have also been calculated. They are in the range of 10−17–10−15 m−1, so LLME at Gadanki are somewhat stronger than those reported so far from Jicamarca, Peru (Lehmacher et al., 2009).

References 1

Berger, U. and von Zahn, U.: Three-dimensional modelling of the trajectories of visible noctilucent cloud particles: An indication of particle nucleation well below the mesopause, J. Geophys. Res., 112, D16204, <a href="http://dx.doi.org/10.1029/2006JD008106">https://doi.org/10.1029/2006JD008106</a>, 2007.

Bremer, J., Hoffmann, P., Höffner, J., Latteck, R., Singer, W., Zecha, M., and Zeller, O.: Long-term changes of mesospheric summer echoes at polar and middle latitudes, J. Atmos. Solar Terr. Phys., 68, 1940–1951, <a href="http://dx.doi.org/10.1016/j.jastp.2006.02.012">https://doi.org/10.1016/j.jastp.2006.02.012</a>, 2006.

Chandra, H., Sinha, H. S. S., Das, U., Misra, R. N., Das, S. R., Datta, J., Chakravarty, S. C., Patra, A. K., Venkateswara Rao, N., and Narayana Rao, D.: First mesospheric turbulence study using coordinated rocket and MST radar measurements over Indian low latitude region, Ann. Geophys., 26, 2725–2738, <a href="http://dx.doi.org/10.5194/angeo-26-2725-2008">https://doi.org/10.5194/angeo-26-2725-2008</a>, 2008.

Czechowsky, P., Rüster, R., and Schmidt, G.: Variations of mesospheric structures in different seasons, Geophys. Res. Lett., 6, 459–462, 1979.

Ecklund, W. L. and Balsley, B. B.: Long-term observations of the arctic mesosphere with the MST radar at Poker Flat, Alaska, J. Geophys. Res., 86, 7775–7780, 1981.

Fukao, S., Yamanaka, M. D., Ao, N., Hocking, W. K., Sato, T., Yamamoto, M., Nakamura, T., Tsuda, T., and Kato, S.: Seasonal variability of vertical eddy diffusivity in the middle atmosphere, 1. Three-year observations by the Middle and Upper atmosphere radar, J. Geophys. Res., 99, 18973–18987, 1994.

Guo, L., Lehmacher, G. A., Kudeki, E., Akgiray, A., Sheth, R., and Chau, J. L.: Turbulent kinetic energy dissipation rates and eddy diffusivities in the tropical mesosphere using Jicamarca radar data, Adv. Space Res., 40, 744–750, <a href="http://dx.doi.org/10.1016/j.asr.2007.05.068">https://doi.org/10.1016/j.asr.2007.05.068</a>, 2007.

Hedin, A. E.: Extension of the MSIS Thermospheric Model into the Middle and Lower Atmosphere, J. Geophys. Res., 96, 1159–1172, 1991.

Hocking, W. K.: Measurement of turbulent energy dissipation rates in the middle atmosphere by radar techniques, Radio Sci., 20, 1403–1422, 1985.

Hocking, W. K.: An assessment of the capabilities and limitations of radars in measurements of upper atmosphere turbulence, J. Adv. Space Res., 17, 1137–1147, 1996.

Kirkwood, S., Barabash, V., Belova, E., Nilsson, H., Rao, N., Stebel, K., Osepian, A., and Chilson, P. B.: Polar Mesosphere Winter Echoes during Solar Proton Events, Advances in Polar Upper Atmosphere Research, 16, 111–125, 2002.

Kirkwood, S., Chilson, P., Belova, E., Dalin, P., Häggström, I., Rietveld, M., and Singer, W.: Infrasound – the cause of strong Polar Mesosphere Winter Echoes?, Ann. Geophys., 24, 475–491, <a href="http://dx.doi.org/10.5194/angeo-24-475-2006">https://doi.org/10.5194/angeo-24-475-2006</a>, 2006.

Kirkwood, S., Wolf, I., Nilsson, H., Dalin, P., Mikhaylova, D., and Belova, E.: Polar mesosphere summer echoes at Wasa, Antarctica (73° S): First observations and comparison with 68° N, Geophys. Res. Lett., 34, L15803, <a href="http://dx.doi.org/10.1029/2007GL030516">https://doi.org/10.1029/2007GL030516</a>, 2007.

Kirkwood, S., Belova, E., Satheesan, K., Narayana Rao, T., Rajendra Prasad, T., and Satheesh Kumar, S.: Fresnel scatter revisited – comparison of 50 MHz radar and radiosondes in the Arctic, the Tropics and Antarctica, Ann. Geophys., 28, 1993–2005, <a href="http://dx.doi.org/10.5194/angeo-28-1993-2010">https://doi.org/10.5194/angeo-28-1993-2010</a>, 2010.

Kubo, K., Sugiyama, K., Nakamura, T., and Fukao, S.: Seasonal and inter annual variability of mesospheric echoes observed with middle and upper atmosphere radar during 1986–1995, Geophys. Res. Lett., 24, 1211–1214, 1997.

Kishore Kumar, G., Venkat Ratnam, M., Patra, A. K., Jagannadha Rao, V. V. M., Vijaya Bhaskar Rao, S., Kishore Kumar, K., Gurubaran, S., Ramkumar, G., and Narayana Rao, D.: Low-latitude mesospheric mean winds observed by Gadanki mesosphere-stratosphere-troposphere (MST) radar and comparison with rocket, High Resolution Doppler Imager (HRDI), and MF radar measurements and HWM93, J. Geophys. Res., 113, D19117, <a href="http://dx.doi.org/10.1029/2008JD009862">https://doi.org/10.1029/2008JD009862</a>, 2008.

Kumar, G. K., Ratnam, M. V., Patra, A. K., Rao, V. V. M. J., Rao, S. V. B., and Rao, D. N.: Climatology of low latitude mesospheric echo characteristics observed by Indian mesosphere, stratosphere, and troposphere radar, J. Geophys. Res., 112, D06109, <a href="http://dx.doi.org/10.1029/2006JD007609">https://doi.org/10.1029/2006JD007609</a>, 2007.

Lehmacher, G. A., Guo, L., Kudeki, E., and Chau, J.: High resolution observations of mesospheric layers with the Jicamarca VHF radar, J. Adv. Space Res., 40, 734–743, 2007.

Lehmacher, G. A., Kudeki, E., Akgiray, A., Guo, L., Reyes, P., and Chau, J.: Radar cross sections for mesospheric echoes at Jicamarca, Ann. Geophys., 27, 2675–2684, <a href="http://dx.doi.org/10.5194/angeo-27-2675-2009">https://doi.org/10.5194/angeo-27-2675-2009</a>, 2009.

Lübken, F.-J., Strelnikov, B., Rapp, M., Singer, W., Latteck, R., Brattli, A., Hoppe, U.-P., and Friedrich, M.: The thermal and dynamical state of the atmosphere during polar mesosphere winter echoes, Atmos. Chem. Phys., 6, 13–24, <a href="http://dx.doi.org/10.5194/acp-6-13-2006">https://doi.org/10.5194/acp-6-13-2006</a>, 2006.

Morris, R. J., Murphy, D. J., Reid, I. M., Holdsworth, D. A., and Vincent, R. A.: First polar mesosphere summer echoes observed at Davis, Antarctica (68.6° S), Geophys. Res. Lett., 31, L16111, <a href="http://dx.doi.org/10.1029/2004GL020352">https://doi.org/10.1029/2004GL020352</a>, 2004.

Narayana Rao, D., Ratnam, M. V., Rao, T. N., and Rao, S. V. B.: Seasonal variation of vertical eddy diffusivity in the troposphere, lower stratosphere and mesosphere over a tropical station, Ann. Geophys., 19, 975–984, <a href="http://dx.doi.org/10.5194/angeo-19-975-2001">https://doi.org/10.5194/angeo-19-975-2001</a>, 2001.

Rao, P. B., Jain, A. R., Kishore, P., Balamuralidhar, P., Damle, S. H., and Viswanathan, G.: Indian MST radar 1. System description and sample vector wind measurements in ST mode, Radio Sci., 30, 1125–1138, <a href="http://dx.doi.org/10.1029/95RS00787">https://doi.org/10.1029/95RS00787</a>, 1995.

Rapp, M. and Lübken, F.-J.: Polar mesosphere summer echoes (PMSE): Review of observations and current understanding, Atmos. Chem. Phys., 4, 2601–2633, <a href="http://dx.doi.org/10.5194/acp-4-2601-2004">https://doi.org/10.5194/acp-4-2601-2004</a>, 2004.

Reid, I. M.: Radar observations of stratified layers in the mesosphere and lower thermosphere (50–100 km), Adv. Space Res., 10, 7–19, 1990.

Sheth, R., Kudeki, E., Lehmacher, G., Sarango, M., Woodman, R., Chau, J., Guo, L., and Reyes, P.: A high-resolution study of mesospheric fine structure with the Jicamarca MST radar, Ann. Geophys., 24, 1281–1293, <a href="http://dx.doi.org/10.5194/angeo-24-1281-2006">https://doi.org/10.5194/angeo-24-1281-2006</a>, 2006.

Smirnova, M., Belova, E., Kirkwood, S., and Mitchell, N.: Polar mesosphere summer echoes with ESRAD, Kiruna, Sweden: Variations and trends over 1997–2008, J. Atmos. Solar-Terr. Phys., 72, 435–447, <a href="http://dx.doi.org/10.1016/j.jastp.2009.12.014">https://doi.org/10.1016/j.jastp.2009.12.014</a>, 2010.

Stebel, K., Blum, U., Fricke, K.-H., Kirkwood, S., Mitchell, N. J., and Osepian, A.: Joint radar/lidar observations of possible aerosol layers in the winter mesosphere, J. Atmos. Solar Terr. Phys., 66, 957–970, 2004.

Swarnalingam, N., Hocking, W. K., and Argall, P. S.: Radar efficiency and the calculation of decade-long PMSE backscatter cross-section for the Resolute Bay VHF radar, Ann. Geophys., 27, 1643–1656, <a href="http://dx.doi.org/10.5194/angeo-27-1643-2009">https://doi.org/10.5194/angeo-27-1643-2009</a>, 2009.

Uma Das, H. S. S., Sinha, Som Sharma, Chandra, H., Das, Sanat K.: Fine structure of the low-latitude mesospheric turbulence, J. Geophys. Res., 114, D10111, <a href="http://dx.doi.org/10.1029/2008JD011307">https://doi.org/10.1029/2008JD011307</a>, 2009.

Weinstock, J.: Using radar to estimate dissipation rates in thin layers of turbulence, Radio Sci., 16, 1401–1406, 1981.

Woodman, R. F. and Guillen, A.: Radar observations of winds and turbulence in the stratosphere and mesosphere, J. Atmos. Sci., 31, 493–503, 1974.

Zecha, M., Bremer, J., Latteck, R., Singer, W., and Hoffmann, P.: Properties of midlatitude mesosphere summer echoes after three seasons of VHF radar observations at 54 N, J. Geophys. Res., 108, 8439, <a href="http://dx.doi.org/10.1029/2002JD002442">https://doi.org/10.1029/2002JD002442</a>, 2003.

Zeller, O., Hoffmann, P., Bremer, J., and Singer, W.: Mesosphere summer echoes, temperature, and meridional wind variations at mid- and polar latitudes, Atmos. Solar Terr. Phys., 71, 931–942, <a href="http://dx.doi.org/10.1016/j.jastp.2009.03.013">https://doi.org/10.1016/j.jastp.2009.03.013</a>, 2009.