The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009
The ionospheric Nighttime Winter Anomaly (NWA) was first reported more than three decades ago based on Total Electron Content (TEC) and vertical sounding data. The aim of this paper is to provide further evidence that the NWA effect is a persistent feature in the northern hemisphere at the American...
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ftdlr:oai:elib.dlr.de:96890 2023-12-31T10:21:41+01:00 The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009 Jakowski, Norbert Hoque, Mohammed Mainul Kriegel, Martin Patidar, Baibhav 2015-10 application/pdf https://elib.dlr.de/96890/ https://elib.dlr.de/96890/1/2015_Jakowski%20etal_JGR_NWA.pdf en eng Wiley https://elib.dlr.de/96890/1/2015_Jakowski%20etal_JGR_NWA.pdf Jakowski, Norbert und Hoque, Mohammed Mainul und Kriegel, Martin und Patidar, Baibhav (2015) The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009. Journal of Geophysical Research, 120 (10), Seiten 9148-9160. Wiley. doi:10.1002/2015JA021600 <https://doi.org/10.1002/2015JA021600>. ISSN 0148-0227. Navigation Zeitschriftenbeitrag PeerReviewed 2015 ftdlr https://doi.org/10.1002/2015JA021600 2023-12-04T00:24:03Z The ionospheric Nighttime Winter Anomaly (NWA) was first reported more than three decades ago based on Total Electron Content (TEC) and vertical sounding data. The aim of this paper is to provide further evidence that the NWA effect is a persistent feature in the northern hemisphere at the American and in the southern hemisphere at the Asian longitude sector under low solar activity conditions. The analysis of ground based GPS derived TEC and peak electron density (NmF2) data from radio occultation measurements on Formosat-3/COSMIC satellites fully confirms and further supports the findings published in earlier NWA papers. So it has been confirmed and further specified that the NWA appears at longitude sectors where the displacement between the geomagnetic and the geographic equator maximizes. To be more precise, the NWA appears in that hemisphere where the geomagnetic latitude exceeds the geographic latitude. Here NWA peaks around 40°-50° geomagnetic mid-latitudes supporting the idea that wind induced plasma uplifting in the conjugated summer hemisphere is the main driving force for the accumulation of ionospheric plasma in the topside ionosphere and plasmasphere. In parallel the midsummer nighttime anomaly (MSNA) is caused after sunset at the local ionosphere. Simultaneously, inter-hemispheric coupling causes severe downward plasma fluxes in the conjugated winter- hemisphere during night strong enough to form the NWA at low solar activity (LSA). With increasing solar activity the downward plasma fluxes, although still present, lose their impact due to the much stronger increasing background ionization that masks the NWA completely and therefore making NWA invisible. It has been shown that MSNA and related special anomalies such as the Weddell Sea Anomaly and the Okhotsk Sea Anomaly introduced in this paper are formed by the same major ionospheric-thermospheric processes that cause also the NWA. Article in Journal/Newspaper okhotsk sea Weddell Sea German Aerospace Center: elib - DLR electronic library Journal of Geophysical Research: Space Physics 120 10 9148 9160 |
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Navigation Jakowski, Norbert Hoque, Mohammed Mainul Kriegel, Martin Patidar, Baibhav The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009 |
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The ionospheric Nighttime Winter Anomaly (NWA) was first reported more than three decades ago based on Total Electron Content (TEC) and vertical sounding data. The aim of this paper is to provide further evidence that the NWA effect is a persistent feature in the northern hemisphere at the American and in the southern hemisphere at the Asian longitude sector under low solar activity conditions. The analysis of ground based GPS derived TEC and peak electron density (NmF2) data from radio occultation measurements on Formosat-3/COSMIC satellites fully confirms and further supports the findings published in earlier NWA papers. So it has been confirmed and further specified that the NWA appears at longitude sectors where the displacement between the geomagnetic and the geographic equator maximizes. To be more precise, the NWA appears in that hemisphere where the geomagnetic latitude exceeds the geographic latitude. Here NWA peaks around 40°-50° geomagnetic mid-latitudes supporting the idea that wind induced plasma uplifting in the conjugated summer hemisphere is the main driving force for the accumulation of ionospheric plasma in the topside ionosphere and plasmasphere. In parallel the midsummer nighttime anomaly (MSNA) is caused after sunset at the local ionosphere. Simultaneously, inter-hemispheric coupling causes severe downward plasma fluxes in the conjugated winter- hemisphere during night strong enough to form the NWA at low solar activity (LSA). With increasing solar activity the downward plasma fluxes, although still present, lose their impact due to the much stronger increasing background ionization that masks the NWA completely and therefore making NWA invisible. It has been shown that MSNA and related special anomalies such as the Weddell Sea Anomaly and the Okhotsk Sea Anomaly introduced in this paper are formed by the same major ionospheric-thermospheric processes that cause also the NWA. |
format |
Article in Journal/Newspaper |
author |
Jakowski, Norbert Hoque, Mohammed Mainul Kriegel, Martin Patidar, Baibhav |
author_facet |
Jakowski, Norbert Hoque, Mohammed Mainul Kriegel, Martin Patidar, Baibhav |
author_sort |
Jakowski, Norbert |
title |
The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009 |
title_short |
The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009 |
title_full |
The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009 |
title_fullStr |
The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009 |
title_full_unstemmed |
The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009 |
title_sort |
persistence of the nighttime winter anomaly (nwa) effect during the low solar activity period 2007-2009 |
publisher |
Wiley |
publishDate |
2015 |
url |
https://elib.dlr.de/96890/ https://elib.dlr.de/96890/1/2015_Jakowski%20etal_JGR_NWA.pdf |
genre |
okhotsk sea Weddell Sea |
genre_facet |
okhotsk sea Weddell Sea |
op_relation |
https://elib.dlr.de/96890/1/2015_Jakowski%20etal_JGR_NWA.pdf Jakowski, Norbert und Hoque, Mohammed Mainul und Kriegel, Martin und Patidar, Baibhav (2015) The Persistence of the Nighttime Winter Anomaly (NWA) Effect During the Low Solar Activity Period 2007-2009. Journal of Geophysical Research, 120 (10), Seiten 9148-9160. Wiley. doi:10.1002/2015JA021600 <https://doi.org/10.1002/2015JA021600>. ISSN 0148-0227. |
op_doi |
https://doi.org/10.1002/2015JA021600 |
container_title |
Journal of Geophysical Research: Space Physics |
container_volume |
120 |
container_issue |
10 |
container_start_page |
9148 |
op_container_end_page |
9160 |
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1786832589655375872 |