Kinematic Solar Wind Model

expi space weather console

ACRONYMS

Model names

HAF	Hakamada Akasofu Fry kinematic solar wind model
ISPM	Interplanetary Shock Propagation Model (solar wind model)
STOA	Shock Time of Arrival (solar wind model)

General Acronyms

AU	Astronomical Unit, ~1.5 x 10⁸ km
FA	False alarm (shock predicted but not observed during the prediction window)
HAF	Hakamada-Akasofu-Fry kinematic solar wind model
IMF	Interplanetary magnetic field
ISPM	Interplanetary Shock Propagation Model (solar wind model)
L1	The Lagrange, or Libration point between the Earth and Sun, ~0.01 AU from the Earth: the location of the ACE and SOHO satellites
Ma	Shock magnetoacoustic Mach number
MHD	Magnetohydrodynamics
PW	Prediction Window. The earliest and latest times for which a forecast is valid
SAT	Shock Arrival Time
SSI	(in HAF) Shock Searching Index as calculated by Sun et al. (a running caculation of Log(DP/ P_min) at each time step in the temporal profile of the data or model output)
SSI	(in ISPM) Shock Strength Index: = log to base 10 of the ratio of dynamic pressure jump at shock to background value. (defined in Smith and Dryer,1990)
STOA	Shock Time of Arrival (solar wind model)

Symbols

P	Dynamic Pressure, 1/2 nmv² (= 1.6726 x 10^-6 nv²) [ ]
D P	the difference in pressure during consecutive time steps (= P(t+1)-P(t))
P_min	the minimum pressure during consecutive time steps (= min(P(t), P(t+1)))
TT_obs	Observed transit time [hrs]
TT_s	Predicted transit time [hrs]
tau	input pulse duration [hrs]
T_event	Time event began
T_obs	Time shock observed at L1 satellite
DT	Tpredict-Tobs [hrs]
V_ave	Average transit speed of shock [km/s] (= 1 AU/ (T_obs-T_event))
V_s	Initial shock speed derived from Solar RadioType II radio drift [km/s. The models assume that the velocity is directed radially outward from the event site along a radial from the center of the Sun. In reality, the velocity vector can be directed elsewhere at the shock's surface and not, necessarily at this direction.
V_sw	Ambient solar wind speed [km/s]. This input is computed internally by HAF and obtained from L1 satelites by STOA. When this data is not available, STOA uses a default value of 400 km/s.
V_cme	CME velocity determined in the plane of the sky from coronagraph observations

Copyright 2006, Exploration Physics International, Inc.