The response of the high-latitude ionosphere to the coronal mass ejection event of April 6, 2000: A practical demonstration of space weather nowcasting with the Super Dual Auroral Radar Network HF radars

2001 ◽  
Vol 106 (A12) ◽  
pp. 30085-30097 ◽  
Author(s):  
J. M. Ruohoniemi ◽  
R. J. Barnes ◽  
R. A. Greenwald ◽  
S. G. Shepherd
Keyword(s):  
Coronal Mass Ejection ◽  
Space Weather ◽  
High Latitude ◽  
Radar Network ◽  
High Latitude Ionosphere ◽  
Mass Ejection ◽  
Ejection Event ◽  
Practical Demonstration

scholarly journals A Statistical study of the Doppler spectral width of high-latitude ionospheric F-region echoes recorded with SuperDARN coherent HF radars

2002 ◽  
Vol 20 (11) ◽  
pp. 1769-1781 ◽  
Author(s):  
J.-P. Villain ◽  
R. André ◽  
M. Pinnock ◽  
R. A. Greenwald ◽  
C. Hanuise
Keyword(s):  
High Latitude ◽  
Statistical Study ◽  
Spectral Width ◽  
Auroral Oval ◽  
F Region ◽  
Radar Network ◽  
Period 2 ◽  
Time Period ◽  
High Latitude Ionosphere ◽  
Data Points

Abstract. The HF radars of the Super Dual Auroral Radar Network (SuperDARN) provide measurements of the E × B drift of ionospheric plasma over extended regions of the high-latitude ionosphere. We have conducted a statistical study of the associated Doppler spectral width of ionospheric F-region echoes. The study has been conducted with all available radars from the Northern Hemisphere for 2 specific periods of time. Period 1 corresponds to the winter months of 1994, while period 2 covers October 1996 to March 1997. The distributions of data points and average spectral width are presented as a function of Magnetic Latitude and Magnetic Local Time. The databases are very consistent and exhibit the same features. The most stringent features are: a region of very high spectral width, collocated with the ionospheric LLBL/cusp/mantle region; an oval shaped region of high spectral width, whose equator-ward boundary matches the poleward limit of the Holzworth and Meng auroral oval. A simulation has been conducted to evaluate the geometrical and instrumental effects on the spectral width. It shows that these effects cannot account for the observed spectral features. It is then concluded that these specific spectral width characteristics are the signature of ionospheric/magnetospheric coupling phenomena.Key words. Ionosphere (auroral ionosphere; ionosphere-magnetosphere interactions; ionospheric irregularities)

scholarly journals Variability of Geomagnetic Field with Interplanetary Magnetic Field at Low, Mid and High Latitudes

2018 ◽  
Vol 10 (2) ◽  
pp. 133-144
Author(s):  
S. Bhardwaj ◽  
P. A. Khan ◽  
R. Atulkar ◽  
P. K. Purohit
Keyword(s):  
Magnetic Field ◽  
Coronal Mass Ejection ◽  
Interplanetary Magnetic Field ◽  
Geomagnetic Storm ◽  
High Latitude ◽  
Geomagnetic Field ◽  
The State ◽  
High Latitudes ◽  
Storm Events ◽  
Mass Ejection

 The fluctuations in the Interplanetary Magnetic Field significantly affect the state of geomagnetic field particularly during the Coronal Mass Ejection (CME) events. In the present investigation we have studied the influence of Interplanetary Magnetic Field changes on the geomagnetic field components at high, low and mid latitudes. To carry out this investigation we have selected three stations viz. Alibag (18.6°N, 72.7°E), Beijing MT (40.3°N, 116.2°E) and Casey (66.2°S, 110.5°E) one each in the low, mid and high latitude regions. Then we selected geomagnetic storm events of three types namely weak (-50≤Dst≤-20), moderate (100≤Dst≤-50) and intense (Dst≤-100nT). In each storm category 10 events were considered. From our study we conclude that geomagnetic field components are significantly affected by the changes in the IMF at all the three latitudinal regions during all the storm events. At the same time we also found that the magnitude of change in geomagnetic field components is highest at the high latitudes during all types of storm events while at low and mid latitude stations the magnitude of effect is approximately the same.

On the Disk Hα and Radio Observations of the 2003 October 28 Flare and Coronal Mass Ejection Event

2005 ◽  
Vol 631 (1) ◽  
pp. L97-L100 ◽  
Author(s):  
Monique Pick ◽  
Jean-Marie Malherbe ◽  
Alain Kerdraon ◽  
Dalmiro Jorge Filipe Maia
Keyword(s):  
Coronal Mass Ejection ◽  
Radio Observations ◽  
Mass Ejection ◽  
Ejection Event

scholarly journals Giant Meterwave Radio Telescope observations of an M2.8 flare: Insights into the initiation of a flare–coronal mass ejection event

Solar Physics ◽  
2003 ◽  
Vol 218 (1/2) ◽  
pp. 247-259 ◽  
Author(s):  
Prasad Subramanian ◽  
S. Ananthakrishnan ◽  
P. Janardhan ◽  
M.R. Kundu ◽  
S.M. White ◽  
...  
Keyword(s):  
Coronal Mass Ejection ◽  
Radio Telescope ◽  
Mass Ejection ◽  
Ejection Event

Quadrupolar Dimmings During a Partial Halo Coronal Mass Ejection Event

Solar Physics ◽  
2011 ◽  
Vol 270 (2) ◽  
pp. 551-559 ◽  
Author(s):  
J. Yang ◽  
Y. Jiang ◽  
R. Zheng ◽  
J. Hong ◽  
Y. Bi ◽  
...  
Keyword(s):  
Coronal Mass Ejection ◽  
Halo Coronal Mass Ejection ◽  
Mass Ejection ◽  
Ejection Event

scholarly journals Verification of real-time WSA−ENLIL+Cone simulations of CME arrival-time at the CCMC from 2010 to 2016

2018 ◽  
Vol 8 ◽  
pp. A17 ◽  
Author(s):  
Alexandra M. Wold ◽  
M. Leila Mays ◽  
Aleksandre Taktakishvili ◽  
Lan K. Jian ◽  
Dusan Odstrcil ◽  
...  
Keyword(s):  
False Alarm ◽  
Coronal Mass Ejection ◽  
Real Time ◽  
Space Weather ◽  
Prediction Error ◽  
Arrival Time ◽  
Model Verification ◽  
Time Error ◽  
Cone Model ◽  
Mass Ejection

The Wang-Sheeley-Arge (WSA)−ENLIL+Cone model is used extensively in space weather operations world-wide to model coronal mass ejection (CME) propagation. As such, it is important to assess its performance. We present validation results of the WSA−ENLIL+Cone model installed at the Community Coordinated Modeling Center (CCMC) and executed in real-time by the CCMC space weather team. CCMC uses the WSA−ENLIL+Cone model to predict CME arrivals at NASA missions throughout the inner heliosphere. In this work we compare model predicted CME arrival-times to in situ interplanetary coronal mass ejection leading edge measurements at Solar TErrestrial RElations Observatory-Ahead (STEREO-A), Solar TErrestrial RElations Observatory-Behind (STEREO-B), and Earth (Wind and ACE) for simulations completed between March 2010 and December 2016 (over 1,800 CMEs). We report hit, miss, false alarm, and correct rejection statistics for all three locations. For all predicted CME arrivals, the hit rate is 0.5, and the false alarm rate is 0.1. For the 273 events where the CME was predicted to arrive at Earth, STEREO-A, or STEREO-B, and was actually observed (hit event), the mean absolute arrival-time prediction error was 10.4 ± 0.9 h, with a tendency to early prediction error of −4.0 h. We show the dependence of the arrival-time error on CME input parameters. We also explore the impact of the multi-spacecraft observations used to initialize the model CME inputs by comparing model verification results before and after the STEREO-B communication loss (since September 2014) and STEREO-A sidelobe operations (August 2014–December 2015). There is an increase of 1.7 h in the CME arrival time error during single, or limited two-viewpoint periods, compared to the three-spacecraft viewpoint period. This trend would apply to a future space weather mission at L5 or L4 as another coronagraph viewpoint to reduce CME arrival time errors compared to a single L1 viewpoint.

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