SH32B-05
SEP modeling based on the ENLIL global heliospheric model
Wednesday, 16 December 2015: 11:20
2009 (Moscone West)
M. Leila Mays1,2, Janet G Luhmann3, Dusan Odstrcil2, Christina Lee3, Hazel M Bain3, Yan Li3, Nathan Schwadron4, Matt Gorby4, Daniel N. Baker5, Ryan M. Dewey6, Davin E Larson7, Jasper S Halekas8, John E P Connerney2, Tycho T von Rosenvinge9, Antoinette Broe Galvin10 and David J McComas11, (1)Catholic University of America, Washington, DC, United States, (2)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (3)University of California Berkeley, Berkeley, CA, United States, (4)University of New Hampshire Main Campus, Space Science Center, Durham, NH, United States, (5)University of Colorado at Boulder, Boulder, CO, United States, (6)Laboratory for Atmospheric and Space Physics, Boulder, CO, United States, (7)Space Sciences Laboratory, Berkeley, CA, United States, (8)University of Iowa, Physics and Astronomy, Iowa City, IA, United States, (9)NASA Goddard SFC, Greenbelt, MD, United States, (10)Univ of New Hampshire, Durham, NH, United States, (11)Southwest Research Institute, San Antonio, TX, United States
Abstract:
The global 3D MHD WSA-ENLIL model provides a time-dependent background heliospheric description, into which a spherical shaped CME can be inserted. Understanding gradual SEP events (often driven by CMEs) well enough to forecast their properties at a given location requires a realistic picture of the global background solar wind through which the shocks and SEPs propagate. Accurate descriptions of the heliosphere, and hence modeled SEPs, are achieved by ENLIL only when the background solar wind is well-reproduced and CME parameters are accurate. It is clear from our preliminary runs that the CMEs sometimes generate multiple shocks, some of which fade while others merge and/or strengthen as they propagate. In order to completely characterize the SEP profiles observed at locations spread in longitude with the aid of these simulations it is essential to include all of the relevant CMEs and allow enough time for the events to propagate and interact. ENLIL provides solar wind parameters and additionally one can extract the magnetic topologies of observer-connected magnetic field lines and all plasma and shock properties along those field lines. ENLIL “likelihood/all-clear” forecasting maps provide expected intensity, timing/duration of events at locations throughout the heliosphere with “possible SEP affected areas” color-coded based on shock strength. ENLIL simulations are also useful to drive SEP models such as the Solar Energetic Particle Model (SEPMOD) and Earth-Moon-Mars Radiation Environment Module (EMMREM). In this presentation we demonstrate case studies of SEP event modeling at locations spread in longitude based on WSA-ENLIL+Cone simulations.
