000007512 001__ 7512
000007512 005__ 20250204104337.0
000007512 0247_ $$2DOI$$a10.3847/1538-4357/ad53c6 
000007512 037__ $$aSCART-2025-0111
000007512 100__ $$aSamara, E
000007512 245__ $$aCalibrating the WSA Model in EUHFORIA Based on Parker Solar Probe Observations
000007512 260__ $$c2024
000007512 520__ $$aWe employ Parker Solar Probe (PSP) observations during the latest solar minimum period (years 2018–2021) to calibrate the version of the Wang–Sheeley–Arge (WSA) coronal model used in the European Heliospheric Forecasting Information Asset (EUHFORIA). WSA provides a set of boundary conditions at 0.1 au necessary to initiate the heliospheric part of EUHFORIA, namely, the domain extending beyond the solar Alfvénic point. To calibrate WSA, we observationally constrain four constants in the WSA semiempirical formula based on PSP observations. We show how the updated (after the calibration) WSA boundary conditions at 0.1 au are compared to PSP observations at similar distances, and we further propagate these conditions in the heliosphere according to EUHFORIA's magnetohydrodynamic (MHD) approach. We assess the predictions at Earth based on the dynamic time-warping technique. Our findings suggest that, for the period of interest, the WSA configurations that resembled optimally the PSP observations close to the Sun were different from the ones needed to provide better predictions at Earth. One reason for this discrepancy can be attributed to the scarcity of fast solar wind velocities recorded by PSP. The calibration of the model was performed based on unexpectedly slow velocities that did not allow us to achieve generally and globally improved solar wind predictions compared to older studies. Other reasons can be attributed to missing physical processes from the heliospheric part of EUHFORIA but also the fact that the currently employed WSA relationship, as coupled to the heliospheric MHD domain, may need a global reformulation beyond that of just updating the four constant factors that were taken into account in this study.
000007512 594__ $$aNO
000007512 6531_ $$aSolar wind
000007512 6531_ $$aMagnetohydrodynamics
000007512 6531_ $$aHeliosphere
000007512 6531_ $$aSpace weather
000007512 700__ $$aArge, C. N
000007512 700__ $$aPinto, R. F
000007512 700__ $$aMagdalenić, J
000007512 700__ $$aWijsen, N
000007512 700__ $$aStevens, M. L
000007512 700__ $$aRodriguez, L
000007512 700__ $$aPoedts, S
000007512 773__ $$c17$$n1$$pThe Astrophysical Journal$$v971$$y2024
000007512 8560_ $$fpavai.valliappan@ksb-orb.be
000007512 905__ $$apublished in
000007512 980__ $$aREFERD