5 research outputs found
Propagating Conditions and the Time of ICME Arrival: A Comparison of the Effective Acceleration Model with ENLIL and DBEM Models
The Effective Acceleration Model (EAM) predicts the Time-of-Arrival
(ToA) of the Coronal Mass Ejection (CME) driven shock and the average
speed within the sheath at 1 AU. The model is based on the assumption
that the ambient solar wind interacts with the interplanetary CME (ICME)
resulting in constant acceleration or deceleration. The upgraded version
of the model (EAMv3), presented here, incorporates two basic
improvements: (i) a new technique for the calculation of the
acceleration (or deceleration) of the ICME from the Sun to 1 AU and (ii)
a correction for the CME plane-of-sky speed. A validation of the
upgraded EAM model is performed via comparisons to predictions from the
ensemble version of the Drag-Based model (DBEM) and the WSA-ENLIL+Cone
ensemble model. A common sample of 16 CMEs/ICMEs, in 2013 - 2014, is
used for the comparison. Basic performance metrics such as the mean
absolute error (MAE), mean error (ME) and root mean squared error (RMSE)
between observed and predicted values of ToA are presented. MAE for EAM
model was 8.7 +/- 1.6 hours while for DBEM and ENLIL was 14.3 +/- 2.2
and 12.8 +/- 1.7 hours, respectively. ME for EAM was -1.4 +/- 2.7 hours
in contrast with -9.7 +/- 3.4 and -6.1 +/- 3.3 hours from DBEM and
ENLIL. We also study the hypothesis of stronger deceleration in the
interplanetary (IP) space utilizing the EAMv3 and DBEM models. In
particularly, the DBEM model perform better when a greater value of drag
parameter, of order of a factor of 3, is used in contrast to previous
studies. EAMv3 model shows a deceleration of ICMEs at greater distances,
with a mean value of 0.72 AU