Unexpected connections between the stratosphere and ionosphere

Abstract

[1] The coupling of the ionosphere to processes from below remains an elusive and difficult problem, as rapidly changing external drivers from above mask variations related to lower atmospheric sources. Here we use superposition of unique circumstances, current deep solar minimum and a record-breaking stratospheric warming event, to gain new insights into causes of ionospheric perturbations. We show large (50-150%) persistent variations in the low-latitude ionosphere (200-1000 km) that occur several days after a sudden warming event in the high-latitude winter stratosphere (∼30 km). We rule out solar irradiance and geomagnetic activity as explanations of the observed variation. Using a general circulation model, we interpret these observations in terms of large changes in atmospheric tides from their nonlinear interaction with planetary waves that are strengthened during sudden warmings. We anticipate that further understanding of the coupling processes with planetary waves, accentuated during the stratospheric sudden warming events, has the potential of enabling the forecast of low-latitude ionospheric weather up to several days in advance.

Ionospheric response to the 2009 sudden stratospheric warming over the equatorial, low, and middle latitudes in the South American sector

“…However, it is very clear that the VTEC was perturbed during 5 or 6 days in all 16 stations, which indicate that the SSW event in the Northern Hemisphere significantly influenced the electron density variations over the equatorial and low latitudes in the Southern Hemisphere. This result agrees with those presented by Goncharenko et al [2010b].…”

“…The present observations over Tucuman are well in coincidence with the results over Okinawa, while the enhancement in the South American sector is found to be little stronger compared to the Asian sector. Other studies of the same events have reported that ionospheric perturbations caused by SSW are stronger in the American sector than in the Asian sector for the January 2009 SSW event [Goncharenko et al, 2010b;Liu et al, 2011] and stronger than in the Asian and African sector for the January 2013 SSW event [Goncharenko et al, 2013a]. The comparison of our observations with other results provides the additional evidence of significant longitudinal variations in the ionospheric response to SSW.…”

“…A similar result was reported by Goncharenko et al [2010aGoncharenko et al [ , 2010b, who noticed that the low-latitude ionosphere perturbation persisted for several days after the SSW peak. Further, a time shift has also been observed in the day maximum behavior after the stratospheric temperature peak.…”

“…As a result of this change in its interaction, the polar stratospheric temperature increases during several days. Recently, an unforeseen coupling between high latitudes, midlatitudes, and equatorial/low latitudes at upper atmospheric/ionospheric altitudes was discovered during sudden stratospheric warming (SSW) events [Goncharenko and Zhang, 2008;Goncharenko et al, 2010aGoncharenko et al, , 2010bGoncharenko et al, , 2013aGoncharenko et al, , 2013bVineeth et al, 2009;Chau et al, 2010Chau et al, , 2012Liu et al, 2011;Pancheva and Mukhtarov, 2011;Bessarab et al, 2012;Fang et al, 2012;Korenkov et al, 2012;Sripathi and Bhattacharyya, 2012;Sumod et al, 2012;Olson et al, 2013;Upadhayaya and Mahajan, 2013;Xiong et al, 2013;Pedatella et al, 2014aPedatella et al, , 2014b. Therefore, various aspects involved behind the effects of SSW need to be explored in order to improve our knowledge about the Earth's atmosphere.…”

Sq and EEJ—A Review on the Daily Variation of the Geomagnetic Field Caused by Ionospheric Dynamo Currents

“…The modulation of the equatorial plasma fountain has been observed in measurements of the F-region equatorial E × B drift (e.g., Chau et al 2009;Fejer et al 2011). Also, the impact on the equatorial anomaly has been revealed by ground-based and satellite measurements of the F-region plasma density (e.g., Goncharenko et al 2010aGoncharenko et al , 2010bYue et al 2010;Pancheva and Mukhtarov 2011;Lin et al 2012). Figure 48 schematically illustrates the vertical coupling of the atmosphere during stratospheric sudden warmings.…”