Journal Article

Solar Wind Forecasting for Long-term Variations of the Global Heliosphere

Dayeh, Maher A, Elliott, Heather A, Gasser, Jonathan, Opher, Merav, Singer, Kelsi N, Sokół, Justyna M

2026

Overview

The large-scale dynamics of the heliosphere is driven by solar activity and variable solar wind (SW) conditions. In situ SW observations inform time-dependent heliosphere modeling efforts but are only available up until the present day, thus restricting informed predictions to the very near future. We developed and implemented a method to provide long-term forecasting of SW parameters at 1 au. Such forecasting supports modeling efforts of the time-dependent global heliosphere by providing realistic boundary conditions for heliospheric models at the upwind model-domain boundary ahead of time in order to understand the global dynamic processes in the heliosphere such as the evolution of the termination shock (TS), heliosheath, and heliopause. Such forecasting capabilities are needed to better constrain the timing of New Horizons’ TS encounter and predict energetic neutral atom flux variation for IMAP. We analyzed SW direct measurement time series for periodicities at various timescales using Lomb–Scargle periodogram analysis. Based on identified prominent periodicities, we construct quasiperiodic functions for the SW parameters. By extrapolating these functions forward in time, we obtain a prediction of the SW evolution over the next two solar cycles. Our results indicate that the next pulse in the SW dynamic pressure, which controls the global heliosphere, will occur around 2035.

• Publisher: IOP Publishing
• Subject: Boundary conditions / Cosmic rays / Dynamic pressure / Evolution / Forecasting / Heliopause / Heliosphere / Heliospheric models / Magnetic fields / Modelling / Neutral atoms / Parameter identification / Periodic variations / Periodicities / Solar activity / Solar cycle / Solar wind / Spacecraft / Time dependence / Wind forecasting