JpGU-AGU Joint Meeting 2017

Presentation information

[EE] Oral

P (Space and Planetary Sciences) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM14] [EE] Dynamics in magnetosphere and ionosphere

Sun. May 21, 2017 9:00 AM - 10:30 AM 105 (International Conference Hall 1F)

convener:Tomoaki Hori(Graduate school of Science, University of Tokyo), Yoshimasa Tanaka(National Institute of Polar Research), Aoi Nakamizo(Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology), Mitsunori Ozaki(Faculty of Electrical and Computer Engineering, Institute of Science and Engineering, Kanazawa University), Chairperson:Atsuki Shinbori(ISEE, Nagoya Univ.), Chairperson:Shin'ya Nakano(The Institute of Statistical Mathematics), Chairperson:Shin-ichiro Oyama(ISEE, Nagoya Univ.)

10:00 AM - 10:15 AM

[PEM14-16] Dayside plasma blob: a different high-density structure from patches in the polar cap

*Qing-He Zhang1, Yu-Zhang Ma1, P. T. JAYACHANDRAN2, J. Moen3, M. Lockwood4, Yong-Liang Zhang5, Yong Wang1, D. R. Themens2 (1.Institute of Space Sciences, Shandong University, Weihai, China, 2.Physics Department, University of New Brunswick, Fredericton, New Brunswick, Canada, 3.Department of Physics, University of Oslo, Blindern, Oslo, Norway, 4.Department of Meteorology, University of Reading, Earley Gate, Post Office Box 243, RG6 6BB, UK., 5.The Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, USA)

Keywords:Polar cap patches, Dayside plasma blobs, Polar Ionosphere, Polar ionosphere-magnetosphere coupling

A new nomenclature of “dayside plasma blob/dayside blob” has been introduced to differentiate another type of enhanced density structures from polar cap patches in the polar ionosphere based on the in situ and ground based observations, by learning from the terminology of auroral blob, a plasma structure within the night-time auroral oval on the closed field lines. Comparing with the polar cap patches, which transported from dayside sunlit region with dense and cold plasma, the dayside blobs are associated with particle precipitations and aurora arcs in the polar cap with dense and hot plasma and strong field-aligned current. Notably, the dayside blobs cause more severe disturbances in the polar cap ionosphere for navigation signals than patches, which will be very useful to grade the importance of space weather phenomena in the polar cap.