TY - JOUR
T1 - Occurrence of F region echoes for the polar cap SuperDARN radars
AU - Koustov, Alexander V.
AU - Ullrich, Sydney
AU - Ponomarenko, Pavlo V.
AU - Nishitani, Nozomu
AU - Marcucci, Federica M.
AU - Bristow, William A.
N1 - Funding Information:
A.V.K. was supported by NSERC Discovery (Canada) grant (RGPIN 03741-2016) and International Joint Research Program of the Institute for Space-Earth Environmental Research, Nagoya University, S.U. was funded by NSERC CREATE (Canada) program (RS346079), P.V.P. was funded by NSERC Discovery (Canada) Grant (RGPIN 1774-2002), N.N. was supported by JSPS KAKENHI (Japan) Grants 16H06286 and 18KK0099, F.M.M. was funded by the PNRA (Italy) Grant 14_00085, W.A.B. was funded by NSF, Directorate of Geosciences (USA) Grants 1443504 and 1341902.
Funding Information:
Continuous funding of the SuperDARN radars by National Scientific Agencies of Australia, Canada, China, France, Italy, Japan, Norway, South Africa, United Kingdom, and the United States of America is appreciated. The current research would be impossible without ongoing support from the Canadian Foundation for Innovation, Canadian Space Agency’s Geospace Observatory (GO Canada) continuation initiative to the U of Saskatchewan radar group and NSERC Discovery grant to AVK. AVK acknowledges funding from the Institute for Space-Earth Environmental Research (ISEE), Nagoya University while he visited the Nagoya University and worked on the paper. For this study, essential are contributions from the Dome C East, McMurdo and South Pole radars. The Dome C East radar was installed in the framework of a French-Italian collaboration and is operated by the Institute for Space Astrophysics and Planetology-Instituto di Astrofisica e Planetologia Spaziali of the Istituto Nazionale di Astrofisica (INAF-IAPS) with the support of Italian National Research Council (CNR) and National Program for Antarctic Research (PNRA).
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Observations by six Super Dual Auroral Radar Network (SuperDARN) polar cap radars, three in the northern hemisphere and three in the southern hemispheres, are considered to assess F region echo occurrence rates over solar, season, and day cycles and to establish relationship between the echo occurrence rate and the background electron density and plasma flow velocity magnitude. The echo occurrence rate is shown to increase toward the solar cycle maximum, more distinctly on the nightside, consistent with a general trend of the background electron density. Over the last 5 years, the echo occurrence rates decline at a rate of 5–10% per year. The pattern of seasonal and diurnal variations in echo occurrence is found to be consistent with previous SuperDARN publications. Minor dips in echo occurrence rate are observed in winter solstices, and these are related to an overall decrease in the electron density. In most of the time sectors, the echo occurrence rate increases with the electron density but only up to a certain threshold value after which the dependence saturates. The level of the saturation depends on season, local time, and average plasma flow velocity magnitude. For the summer daytime observations, the echo occurrence rate correlates with variations of both electron density and plasma flow velocity magnitude.[Figure not available: see fulltext.].
AB - Observations by six Super Dual Auroral Radar Network (SuperDARN) polar cap radars, three in the northern hemisphere and three in the southern hemispheres, are considered to assess F region echo occurrence rates over solar, season, and day cycles and to establish relationship between the echo occurrence rate and the background electron density and plasma flow velocity magnitude. The echo occurrence rate is shown to increase toward the solar cycle maximum, more distinctly on the nightside, consistent with a general trend of the background electron density. Over the last 5 years, the echo occurrence rates decline at a rate of 5–10% per year. The pattern of seasonal and diurnal variations in echo occurrence is found to be consistent with previous SuperDARN publications. Minor dips in echo occurrence rate are observed in winter solstices, and these are related to an overall decrease in the electron density. In most of the time sectors, the echo occurrence rate increases with the electron density but only up to a certain threshold value after which the dependence saturates. The level of the saturation depends on season, local time, and average plasma flow velocity magnitude. For the summer daytime observations, the echo occurrence rate correlates with variations of both electron density and plasma flow velocity magnitude.[Figure not available: see fulltext.].
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U2 - 10.1186/s40623-019-1092-9
DO - 10.1186/s40623-019-1092-9
M3 - Article
AN - SCOPUS:85074194857
VL - 71
JO - Earth, Planets and Space
JF - Earth, Planets and Space
SN - 1343-8832
IS - 1
M1 - 112
ER -