- Open Access
Equatorial GPS ionospheric scintillations over Kototabang, Indonesia and their relation to atmospheric waves from below
Earth, Planets and Space volume 61, pages397–410(2009)
Using Global Positioning System (GPS) satellites, we have been conducting equatorial ionospheric scintillation observations at Kototabang, Indonesia since January 2003. Scintillations caused by equatorial plasma bubbles appear between 2000 and 0100 LT in equinoctial months with a seasonal asymmetry, and their activity decreases with decreasing solar activity. A comparison between scintillation index (S4) and Earth’s brightness temperature (Tbb) variations suggests that the scintillation activity can be related to tropospheric disturbances over the Indian Ocean to the west of Kototabang. To understand better the reasons of day-to-day variability of S4, we analyze S4, Tbband lower thermospheric neutral wind () data. The results show that S4 fluctuates with periods of about 2.5, 5, 8, 14 and 25 days, possibly due to atmospheric waves from below and that similar periods are also found in the Tbband variations. Using a general circulation model, we made numerical simulations to determine the behavior of neutral wind in the equatorial thermosphere. The results indicate the following: (1) 2- to 20-day waves dissipate rapidly above about an altitude of 125 km, and 0.5- to 3-hour waves become predominant above 100 km, (2) zonal winds above 200 km altitude are, on the whole, eastward during sunset-sunrise, (3) zonal wind patterns due to short-period (1–4 h) atmospheric gravity waves (AGWs) above 120 km altitude change day by day, exhibit wavy structures with scale lengths of about 30–1000 km and, as a whole, move eastward at about 100−1 while changing patterns over time. These simulations suggest that the Rayleigh-Taylor instability responsible for plasma bubble generation can be seeded by AGWs with short periods of about 0.5–3 h, and that background conditions necessary for this instability are modulated by planetary-scale atmospheric waves propagating up to an altitude of about 120 km from below.
Abdu, M. A., Outstanding problems in the equatorial ionosphere-thermosphere electrodynamics relevant to spread F, J. Atmos. Sol.-Terr. Phys., 63, 869–884, 2001.
Abdu, M. A., P. P. Batista, I. S. Batista, C. G. M. Brum, A. J. Carrasco, and B. W. Reinisch, Planetary wave oscillations in mesospheric winds, equatorial evening prereversal electric field and spread F, Geophys. Res. Lett., 33, L07107, doi:10.1029/2005GL024837, 2006a.
Abdu, M. A., T. K. Ramkumar, I. S. Batista, C. G. M. Brum, H. Takahashi, B. W. Reinisch, and J. H. Sobral, Planetary wave signatures in the equatorial atmosphere-ionosphere system, and mesosphere-E- an F-region coupling, J. Atmos. Sol.-Terr. Phys., 68, 509–522, 2006b.
Basu, Su. and S. Basu, Equatorial scintillations: Advances since ISEA-6, J. Atmos. Terr. Phys., 47, 753–768, 1985.
Basu, Su., S. Basu, J. P. MuClure, W. B. Hanson, and H. E. Whitney, High resolution topside in situ data of electron densities and VHF/GHz scintillations in the equatorial region, J. Geophys. Res., 88, 403–415, 1983.
Basu, S., E. MacKenzie, and Su. Basu, Ionospheric constraints of VHF/UHF communications links during solar maximum and minimum periods, Radio Sci., 23, 363–378, 1988.
Beach, T. L. and P. M. Kintner, Simultaneous Global Positioning System observations of equatorial scintillations and total electron content fluctuations, J. Geophys. Res., 104, 22,553–22,565, 1999.
Burke, W. J., C. Y. Huang, L. C. Gentile, and L. Bauer, Seasonal-longitudinal variability of equatorial plasma bubbles, Ann. Geophys., 22, 3089–3098, 2004.
Farley, D. T., E. Bonelli, B. G. Fejer, and M. F. Larsen, The prereversal of the zonal electric field in the equatorial ionosphere, J. Geophys. Res., 91, 13,723–13,728, 1986.
Forbes, J. M., Planetary waves in the thermosphere-ionosphere system, J. Geomag. Geoelectr., 48, 91–98, 1996.
Fukao, S., Y. Ozawa, T. Yokoyama, M. Yamamoto, and R. T. Tsunoda, First observations of the spatial structure of F region 3-m-scale field-aligned irregularities with Equatorial Atmosphere Radar in Indonesia, J. Geophys. Res., 109, A02304, doi:10.1029/2003JA010096, 2004.
Fukao, S., T. Yokoyama, T. Tayama, M. Yamamoto, T. Maruyama, and S. Saito, Eastward traverse of equatorial plasma plumes observed with the Equatorial Atmosphere Radar in Indonesia, Ann. Geophys., 24, 1411–1418, 2006.
Gentile, L. C., W. J. Burke, and F. J. Rich, A global climatology for equatorial plasma bubbles in the topside ionosphere, Ann. Geophys., 24, 163–172, 2006.
Hocke, K. and T. Tsuda, Gravity waves and ionospheric irregularities over tropical convection zones observed by GPS/MET radio occultation, Geophys. Res. Lett., 28, 2815–2818, 2001.
Hysell, D. L. and E. Kudeki, Collisional shear instability in the equatorial F region ionosphere, J. Geophys. Res., 109, A11301, doi:10. 1029/2004JA010636, 2004.
Hysell, D. L., M. C. Kelley, W. E. Swartz, and R. F. Woodman, Seeding and layering of equatorial spread F by gravity waves, J. Geophys. Res., 95, 17,253–17,260, 1990.
Hysell, D. L., J. Chun, and J. L. Chau, Bottom-type scattering layers and equatorial spread F, Ann. Geophys., 22, 4061–4069, 2004.
Hysell, D. L., M. F. Larsen, C. M. Swenson, and T. F. Wheeler, Shear flow effects at the onset of equatorial spread F, J. Geophys. Res., 111, A11317, doi:10.1029/2006JA011963, 2006.
Kelley, M. C., M. F. Larsen, C. LaHoz, and J. P. McClure, Gravity wave initiation of equatorial spread F: A case study, J. Geophys. Res., 86, 9087–9100, 1981.
Kudeki, E. and S. Bhattacharyya, Postsunset vortex in equatorial F-region plasma drifts and implications for bottomside spread-F, J. Geophys. Res., 104, 28,163–28,170, 1999.
Laštovička, J., Forcing of the ionosphere by waves from below, J. Atmos. Sol.-Terr. Phys., 68, 479–497, 2006.
Lin, C. S., T. J. Immel, H. C. Yeh, S. B. Mende, and J. L. Burch, Simultaneous observations of equatorial plasma depletion by IMAGE and ROCSAT-1 satellites, J. Geophys. Res., 110, A06304, doi:10.1029/2004JA010774, 2005.
Maruyama, T. and N. Matuura, Longitudinal variability of annual changes in activity of equatorial spread F and plasma bubbles, J. Geophys. Res., 89, 10,903–10,912, 1984.
McClure, J. P., S. Singh, D. K. Bamgboye, F. S. Johnson, and H. Kil, Occurrence of equatorial F region irregularities: Evidence for tropospheric seeding, J. Geophys. Res., 103, 29,119–29,135, 1998.
Miyoshi, Y., Temporal variation of nonmigrating diurnal tide and its relation with the moist convective activity, Geophys. Res. Lett., 33, L11815, doi:10.1029/2006GL026702, 2006.
Miyoshi, Y. and H. Fujiwara, Excitation mechanism of intraseasonal oscillation in the equatorial mesosphere and lower thermosphere, J. Geophys. Res., 111, D14108, doi:10.1029/2005JD006993, 2006.
Miyoshi, Y. and H. Fujiwara, Gravity waves in the thermosphere simulated by a general circulation model, J. Geophys. Res., 113, D01101, doi: 10.1029/2007JD008874, 2008.
Ogawa, T., E. Sagawa, Y. Otsuka, K. Shiokawa, T. J. Immel, S. B. Mende, and P. Wilkinson, Simultaneous ground- and satellite-based airglow observations of geomagnetic conjugate plasma bubbles in the equatorial anomaly, Earth Planets Space, 57, 385–392, 2005.
Ogawa, T., Y. Otsuka, K. Shiokawa, A. Saito, and M. Nishioka, Ionospheric disturbances over Indonesia and their possible association with atmospheric gravity waves from the troposphere, J. Meteor. Soc. Jpn., 84A, 327–342, 2006.
Otsuka, Y., K. Shiokawa, T. Ogawa, and P. Wilkinson, Geomagnetic conjugate observations of equatorial airglow depletions, Geophys. Res. Lett., 29(15), doi:10.1029/2002GL015347, 2002.
Otsuka, Y., K. Shiokawa, T. Ogawa, T. Yokoyama, M. Yamamoto, and S. Fukao, Spatial relationship of equatorial plasma bubbles and field-aligned irregularities observed with an all-sky airglow imager and the Equatorial Atmosphere Radar, Geophys. Res. Lett., 31, L20802, doi:10.1029/2004GL020869, 2004.
Otsuka, Y., K. Shiokawa, and T. Ogawa, Equatorial ionospheric scintillations and zonal irregularity drifts observed with closely-spaced GPS receivers in Indonesia, J. Meteor. Soc. Jpn., 84A, 343–351, 2006.
Prakash, S., Production of electric field perturbations by gravity wave winds in the E region suitable for initiating equatorial spread F, J. Geophys. Res., 104, 10,051–10,069, 1999.
Röttger, J., Travelling disturbances in the equatorial ionosphere and their association with penetrative cumulus convection, J. Atmos. Terr. Phys., 39, 987–998, 1977.
Röttger, J., Equatorial spread-F by electric fields and atmospheric gravity waves generated by thunderstorms, J. Atmos. Terr. Phys., 43, 453–462, 1981.
Saito, S. and T. Maruyama, Large-scale longitudinal variation in ionospheric height and equatorial spread F occurrences observed by ionosondes, Geophys. Res. Lett., 34, L16109, doi:10.1029/2007GL030618, 2007.
Shiokawa, K., Y. Otsuka, T. Ogawa, and P. Wilkinson, Time evolution of high-altitude plasma bubbles imaged at geomagnetic conjugate points, Ann. Geophys., 22, 3137–3143, 2004.
Shiokawa, K., Y. Otsuka, and T. Ogawa, Quasiperiodic southward moving waves in 630-nm airglow images in the equatorial thermosphere, J. Geophys. Res., 111, A06301, doi:10.1029/2005JA011406, 2006.
Singh, S., F. S. Johnson, and R. A. Power, Gravity wave seeding of equatorial plasma bubbles, J. Geophys. Res., 102, 7399–7410, 1997.
Sridharan, S., T. Tsuda, R. A. Vincent, T. Nakamura, and Effendy, A report on radar observations of 5–8-day waves in the equatorial MLT region, J. Meteor. Soc. Jpn., 84A, 295–304, 2006.
Sultan, F. J., Linear theory and modeling of the Rayleigh-Taylor instability leading to the occurrence of equatorial spread F, J. Geophys. Res., 101, 26,875–26,891, 1996.
Takahashi, H., L. M. Lima, C. W. Wrasse, M. A. Abdu, I. S. Batista, D. Gobbi, R. A. Buriti, and P. P. Batista, Evidence on 2–4 day oscillations of the equatorial ionosphere h′F and mesospheric airglow emissions, Geophys. Res. Lett., 32, L12102, doi:10.1029/2004GL022318, 2005.
Takahashi, H., C. W. Wrasse, D. Pancheva, M. A. Abdu, I. S. Batista, L. M. Lima, P. P. Batista, B. R. Clemesha, and K. Shiokawa, Signatures of 3–6 day planetary waves in the equatorial mesosphere and ionosphere, Ann. Geophys., 24, 3343–3350, 2006.
Takahashi, H. et al., Signatures of ultra fast Kelvin waves in the equatorial middle atmosphere and ionosphere, Geophys. Res. Lett., 34, L11108, doi:10.1029/2007GL029612, 2007.
Tsuda, T. and K. Hocke, Application of GPS radio occultation data for studies of atmospheric waves in the middle atmosphere and ionosphere, J. Meteor. Soc. Jpn., 82, 419–426, 2004.
Tsuda, T., M. Nishida, C. Rocken, and R. H. Ware, A global morphology of gravity wave activity in the stratosphere revealed by the GPS occultation data (GPS/MET), J. Geophys. Res., 105, 7257–7273, 2000.
Tsunoda, R. T., On the enigma of day-to-day variability in the equatorial spread F, Geophys. Res. Lett., 32, L08103, doi:10.1029/2005GL022512, 2005.
Vadas, S. L., Horizontal and vertical propagation and dissipation of gravity waves in the thermosphere from lower atmospheric and thermospheric sources, J. Geophys. Res., 112, A06305, doi:10.1029/2006JA011845, 2007.
Vadas, S. L. and D. C. Fritts, Thermospheric responses to gravity waves arising from mesoscale convective complexes, J. Atmos. Sol.-Terr. Phys., 66, 781–804, 2004.
Vadas, S. L. and D. C. Fritts, Influence of solar variability on gravity wave structure and dissipation in the thermosphere from tropospheric convection, J. Geophys. Res., 111, A10S12, doi:10.1029/2005JA011510, 2006.
Woodman, R. F. and C. LaHoz, Radar observations of F region equatorial irregularities, J. Geophys. Res., 81, 5447–5466, 1976.
Yokoyama, T., S. Fukao, and M. Yamamoto, Relationship of the onset of equatorial F region irregularities with the sunset terminator observed with the Equatorial Atmosphere Radar, Geophys. Res. Lett., 31, L24804, doi:10.1029/2004GL021529, 2004.
About this article
Cite this article
Ogawa, T., Miyoshi, Y., Otsuka, Y. et al. Equatorial GPS ionospheric scintillations over Kototabang, Indonesia and their relation to atmospheric waves from below. Earth Planet Sp 61, 397–410 (2009). https://doi.org/10.1186/BF03353157
- Equatorial ionosphere
- GPS scintillation
- plasma bubble
- atmospheric wave
- tropospheric disturbance