Inner heliosphere MHD modeling system applicable to space weather forecasting for the other planets

Abstract

We developed a magnetohydrodynamic (MHD) solar wind model which can be used for practical use in real-time space weather forecasting at Earth's orbit and those of other planets. The MHD simulation covering 3 years (2007)(2008)(2009)) was performed to test the accuracy, and the numerical results show reasonable agreement with in situ measurements of the solar wind at Earth's orbit and with measurements at Venus and Mars by Venus Express and Mars Express, respectively. The comparison also shows that the numerical results can be used to detect stream interfaces, which is useful for space weather forecast of killer electrons in the outer Van Allen belt.

Magnetohydrodynamic simulation of interplanetary propagation of multiple coronal mass ejections with internal magnetic flux rope (SUSANOO‐CME)

“…The 1 order of magnitude higher background density (seen in 27 October in Figure d) can be the cause of the delay of the shock arrival. The background density is specified as a function of modeled solar wind velocity in our model [ Shiota et al , ]. However, the modeled solar wind speed during 27 October is much lower than the observed one (Figure c).…”

“…Many research groups have developed different types of MHD simulation and compared the results to the measured the solar wind in the inner heliosphere [e.g., Pizzo , ; Usmanov , , ; Riley et al , ; Odstrcil , ; Roussev et al , ; Detman et al , ; Cohen et al , ; Owens et al , ; MacNeice , ; Nakamizo et al , ; Pahud et al , ; Feng et al , ; Merkin et al , ; Yang et al , ; Hayashi , ]. Recently, we developed a new MHD model of the background solar wind in the inner heliosphere based on the time series of daily synoptic observations of the photospheric magnetic field (hereafter, SUSANOO‐SW model (Space‐weather‐forecast‐Usable System Anchored by Numerical Operations and Observations, Solar Wind model) [ Shiota et al , ]. The time profile of the estimated solar wind MHD parameters sampled at several planets show reasonable agreement with in situ measurements.…”

Radiation dose forecast of WASAVIES during ground‐level enhancement

“…The physics‐based forward model as shown in section 2 works just after the detection of GLE onset by the GLE alarm system [ Kuwabara et al ., ]. We use the reconstructed solar wind structures [ Shiota et al ., ] in real time by Space‐weather‐forecast‐Usable System Anchored by Numerical Operations and Observations (SUSANOO) project (http://st4a.stelab.nagoya-u.ac.jp/susanoo/) to select the slow‐ or fast‐type Parker spiral for the pitch angle sampling, and we use the current Kp index to make the T89 magnetic field. The mean free path of 1 GeV proton is fixed at 0.4 AU, and Figure gives the possible injection profiles by dotted areas for a given heliolongitude.…”

Japanese space weather research activities

“…Forecasting and Modeling Activity . Recently, ISEE has developed a numerical space weather forecast system Space weather‐forecast Usable System Anchored by Numerical Operations and Observations (SUSANOO) including a solar wind MHD model in the inner heliosphere [ Shiota et al ., ] (Figure ) and radiation belt [ Miyoshi et al ., ]. Using daily solar photospheric magnetic field observations, the solar wind MHD model simulates the solar wind variations for the next 7 days, which are used to drive the radiation belt model to forecast the space radiation.…”