Statistical Similarities Between WSA‐ENLIL+Cone Model and MAVEN in Situ Observations From November 2014 to March 2016

Abstract

Normal solar wind flows and intense solar transient events interact directly with the upper Martian atmosphere due to the absence of an intrinsic global planetary magnetic field. Since the launch of the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission, there are now new means to directly observe solar wind parameters at the planet's orbital location for limited time spans. Due to MAVEN's highly elliptical orbit, in situ measurements cannot be taken while MAVEN is inside Mars' magnetosheath. To model solar wind conditions during these atmospheric and magnetospheric passages, this research project utilized the solar wind forecasting capabilities of the WSA‐ENLIL+Cone model. The model was used to simulate solar wind parameters that included magnetic field magnitude, plasma particle density, dynamic pressure, proton temperature, and velocity during a four Carrington rotation‐long segment. An additional simulation that lasted 18 Carrington rotations was then conducted. The precision of each simulation was examined for intervals when MAVEN was in the upstream solar wind, that is, with no exospheric or magnetospheric phenomena altering in situ measurements. It was determined that generalized, extensive simulations have comparable prediction capabilities as shorter, more comprehensive simulations. Generally, this study aimed to quantify the loss of detail in long‐term simulations and to determine if extended simulations can provide accurate, continuous upstream solar wind conditions when there is a lack of in situ measurements.

Upstream Solar Wind Prediction up to Mars by an Operational Solar Wind Prediction System

“…Lentz et al. (2018) also compared the model performance of WSA‐Enlil model in predicting the solar wind at Mars from late December 2015 to March 2016, and found that the model provide a MSE within the range of [1.07 × 10 4 , 1.59 × 10 4 ] km 2 /s 2 for solar wind speed, a MSE within the range of [8.00, 14.55] cm −6 for solar wind density, a MSE within the range of [7.80, 17.53] nT 2 for magnetic field. According to the RMSE of the HSA subgroup in predicting the solar wind at Mars listed in Table 3, our model provide MSE within the range of [0.94 × 10 4 , 1.03 × 10 4 ] km 2 /s 2 for solar wind speed, MSE within the range of [18.83, 22.28] cm −6 for solar wind density, MSE within the range of [14.74, 19.45] nT 2 for magnetic field.…”

Acceleration of Energetic Ions in Corotating Interaction Region near 1.5 au: Evidence from MAVEN

“…It maybe noted here that the WSA-ENLIL+Cone simulations are used only to get a general picture of what these events might have looked like on a larger scale at 1 and 1.5 AU. Though the WSA-ENLIL+Cone can provide short-term all-inclusive forecasts which are closer to the observations, the long-term forecasts may be imprecise in details (Lentz et al 2018;Falkenberg et al 2011). However, the predictions are reasonably accurate within 1 AU (Mays et al 2015); and therefore the simulations at STEREO locations (where observations are not available) are expected to be reasonable.…”