An Advanced Surface Flux Transport Model for Space Weather

The solar magnetic field (B) plays a key role in solar and heliospheric physics and is a crucial input for Space Weather Models. This input is in the form of full-Sun maps of B. Standard observatory maps are constructed diachronically and contain data that is as much as 27 days old. Assimilative Surface Flux transport (SFT) models can improve upon this input, by incorporating known surface flows and processes to produce a continuous approximation of the state of the photospheric magnetic field, as a sequence maps. These synchronic maps can allow space weather models to produce more accurate results. To assess uncertainty and sensitivity of solutions, SFT should produce multiple map realization sequences. Presently available SFTs are based on legacy codes that computationally can provide only a small number of realizations at low resolution in a practical amount of time. None are open source. Our project will develop OFTSWA (OFT for Space Weather Applications), an advanced SFT that will acquire and assimilate magnetograms and rapidly produce multiple realizations at high resolution that estimate the present state of the Sun's surface magnetic field. It is based the Open-source Flux Transport (OFT) model. In phase I, we will extend OFT to multiple data sources and demonstrate a prototype of OFTSWA for a solar cycle with multiple realizations. In phase II, we will deliver OFTSWA to the CCMC, along with interfaces and tools that will the community to interact with OFTSWA and create map sequences for use in a variety of space weather models and applications. Within NASA, OFTSWA will be beneficial to the Community Coordinate Modeling Center (CCMC), especially as part of their support to the Moon to Mars Space weather Analysis Office. Outside NASA, NOAA Space Weather Prediction Center and the Air Force also require solar magnetic maps for Space Weather Models.
Benefits: Full-Sun maps of the solar photospheric magnetic field are a key input to Space Weather models. Twelve of the models currently available at NASA CCMC require solar magnetic maps as input (or products/results derived from them). NASA CCMC also supports NASA'a Moon to Mars (M2M) Space Weather Analysis Office with near real-time runs of Space Weather models that require solar magnetic maps. Our proposed project will create OFTSWA (Open-source Flux Transport for Space Weather Applications), an advanced SFT that will acquire and assimilate magnetograms and rapidly produce multiple realizations at high resolution that estimate the present state of the Sun's surface magnetic field. OFTSWA will provide crucial inputs for NASA Space Weather models. NOAA Space Weather Prediction Center (SWPC) runs The WSA-Enlil forecast model to predict the arrival of solar wind structures and coronal mass ejections (CMEs) at Earth. It requires full Sun magnetic maps at a cadence of one per hours. OFTSWA will provide maps with multiple realizations and high resolution, potentially improving their forecasts. Forward predictions of the solar magnetic flux are used in irradiance forecasts, which can inform Air Force models of the thermosphere/ionosphere. OFTSWA can address these requirements as well.