Physics
Scientific paper
Dec 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006agufmsm31a0303z&link_type=abstract
American Geophysical Union, Fall Meeting 2006, abstract #SM31A-0303
Physics
2700 Magnetospheric Physics (6939), 2740 Magnetospheric Configuration And Dynamics, 2776 Polar Cap Phenomena, 2784 Solar Wind/Magnetosphere Interactions, 2790 Substorms
Scientific paper
Convection and its changes are related to geomagnetic disturbances such as substorms, dynamic pressure disturbances and convection bays. Furthermore, convection is theoretically related to evolution of the Harang electric field reversal (or "discontinuity"), which has been related observationally and theoretically to these disturbances. Interplanetary measurements are generally used for studying and making associations of convection with the onsets and temporal evolution of disturbances. This is generally okay for statistical studies, but spatial structure and propagation timing errors due to the highly variable orientation of interplanetary structures create significant ambiguity for case studies and have prevented definitive understanding. Direct observation of dayside convection with high time resolution offers a potential solution to this problem. Here we introduce how we use the Sondrestrom incoherent scatter radar to observe dayside convection. Up to now, we have studied 31 6-8 hr measurement intervals. Combined with the measurements by solar wind monitors upstream of the magnetosphere, LANL geosynchronous satellite and ground magnetometers, we demonstrate that the radar observations have the ability to accurately monitor dayside convection with ~2 min resolution. Furthermore, the observations clearly show the convection changes from IMF Bz, By and solar wind dynamic pressure variations and thus shed light on how the magnetosphere and ionosphere respond to external driving. As an application, we use this technique to study the relationship between convection changes and substorm onsets. For the majority of substorms we have studied, a clear convection flow change, either flow speed decrease and/or flow direction change, is seen at substorm onset. In the future, we will use this technique to study the relationships between convection, other geomagnetic disturbances and the Harang reversal, as well as to evaluate the preceding convection strength and duration and the convection changes that lead to substorm onset.
Heinselman Craig
Lyons Larry
McCready Mary
Zou Shengrong
No associations
LandOfFree
Observation of Dayside Convection by Sondrestrom Incoherent Scatter Radar and its Application to Substorm Triggering Study does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Observation of Dayside Convection by Sondrestrom Incoherent Scatter Radar and its Application to Substorm Triggering Study, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observation of Dayside Convection by Sondrestrom Incoherent Scatter Radar and its Application to Substorm Triggering Study will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-972124