The present work uses the Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM),under geomagnetically disturbed conditions that are closely related to the southward interplanetary magnetic field(IM...The present work uses the Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM),under geomagnetically disturbed conditions that are closely related to the southward interplanetary magnetic field(IMF),to investigate how the nighttime poleward wind(30°–50°magnetic latitude and 19–22 magnetic local time)responds to subauroral polarization streams(SAPS)that commence at different universal times(UTs).The SAPS effects on the poleward winds show a remarkable UT variation,with weaker magnitudes at 00 and 12 UT than at 06 and 18 UT.The strongest poleward wind emerges when SAPS commence at 06 UT,and the weakest poleward wind develops when SAPS occur at 00 UT.A diagnostic analysis of model results shows that the pressure gradient is more prominent for the developing of the poleward wind at 00 and 12 UT.Meanwhile,the effect of ion drag is important in the modulation of the poleward wind velocity at 06 and 18 UT.This is caused by the misalignment of the geomagnetic and geographic coordinate systems,resulting in a large component of ion drag in the geographically northward(southward)direction due to channel orientation of the SAPS at 06 and 18 UT(00 and 12 UT).The Coriolis force effect induced by westward winds maximizes(minimizes)when SAPS commence at 12 UT(00 UT).The centrifugal force due to the accelerated westward winds shows similar UT variations as the Coriolis force,but with an opposite effect.展开更多
ESTABLISHED at the Nanjing Teachers’ University, members of the Loving Fund, a group of university students and teachers who participate in charitable activities to aid poor students, has gradually increased its infl...ESTABLISHED at the Nanjing Teachers’ University, members of the Loving Fund, a group of university students and teachers who participate in charitable activities to aid poor students, has gradually increased its influence throughout the university and society. In 1992, 69 new students from southern and northern Jiangsu展开更多
基金the National Science Foundation.The work is supported by the National Nature Science Foundation of China(No.s 41974182,41674153,41521063,41431073,41521062 and 42004135)the US NSF award AGS-1762141 and the US AFOSR MURI award FA9559-16-1-0364+1 种基金the NSF grant AGS-1452309The Spark Project at Wuhan University(2042020gf0024)also sponsors this work.
文摘The present work uses the Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM),under geomagnetically disturbed conditions that are closely related to the southward interplanetary magnetic field(IMF),to investigate how the nighttime poleward wind(30°–50°magnetic latitude and 19–22 magnetic local time)responds to subauroral polarization streams(SAPS)that commence at different universal times(UTs).The SAPS effects on the poleward winds show a remarkable UT variation,with weaker magnitudes at 00 and 12 UT than at 06 and 18 UT.The strongest poleward wind emerges when SAPS commence at 06 UT,and the weakest poleward wind develops when SAPS occur at 00 UT.A diagnostic analysis of model results shows that the pressure gradient is more prominent for the developing of the poleward wind at 00 and 12 UT.Meanwhile,the effect of ion drag is important in the modulation of the poleward wind velocity at 06 and 18 UT.This is caused by the misalignment of the geomagnetic and geographic coordinate systems,resulting in a large component of ion drag in the geographically northward(southward)direction due to channel orientation of the SAPS at 06 and 18 UT(00 and 12 UT).The Coriolis force effect induced by westward winds maximizes(minimizes)when SAPS commence at 12 UT(00 UT).The centrifugal force due to the accelerated westward winds shows similar UT variations as the Coriolis force,but with an opposite effect.
文摘ESTABLISHED at the Nanjing Teachers’ University, members of the Loving Fund, a group of university students and teachers who participate in charitable activities to aid poor students, has gradually increased its influence throughout the university and society. In 1992, 69 new students from southern and northern Jiangsu