| タイトル | Using Polar Coronal Hole Area Measurements to Determine the Solar Polar Magnetic Field Reversal in Solar Cycle 24 |
| 本文（外部サイト） | http://hdl.handle.net/2060/20150007708 |
| 著者（英） | Pesnell, W.D.; Webber, S.A. Hess; Karna, N. |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2014-05-06 |
| 言語 | eng |
| 内容記述 | An analysis of solar polar coronal hole (PCH) areas since the launch of the Solar Dynamics Observatory (SDO) shows how the polar regions have evolved during Solar Cycle 24. We present PCH areas from mid-2010 through 2013 using data from the Atmospheric Imager Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) instruments onboard SDO. Our analysis shows that both the northern and southern PCH areas have decreased significantly in size since 2010. Linear fits to the areas derived from the magnetic-field properties indicate that, although the northern hemisphere went through polar-field reversal and reached solar-maximum conditions in mid-2012, the southern hemisphere had not reached solar-maximum conditions in the polar regions by the end of 2013. Our results show that solar-maximum conditions in each hemisphere, as measured by the area of the polar coronal holes and polar magnetic field, will be offset in time. |
| NASA分類 | Astronomy; Astrophysics; Solar Physics |
| レポートNO | GSFC-E-DAA-TN22816
GSFC-2015027P |
| 権利 | Copyright, Distribution as joint owner in the copyright |
