Empirical solar wind forecasting from the chromosphere

Recently, we (McIntosh & Leamon, 2005) correlated the inferred structure of the solar chromospheric plasma topography with in situ solar wind velocity and composition data measured at 1 AU. Specifically, the measured separation in height of the TRACE 1600Å and 1700Å UV band pass filters correlate very strongly with solar wind velocity and inversely with the ratio of ionic oxygen (O ⁷⁺/O ⁶⁺) densities. These correlations suggest that the structure of the solar wind is rooted deeper in the outer solar atmosphere than has been previously considered. We show here that the value of plasma β extrapolated from the photosphere up into the chromosphere correlates with TRACE UV band pass separation and thus to in situ solar wind velocity and composition. We present initial results of a model developed to so predict interplanetary solar wind conditions, using SOHO/MDI magnetograms with 96 minute cadence as input. Our model provides a near continuous range of solar wind speeds and composition quantities from the structure of the chromosphere and is more precise than the old "fast/ coronal hole or slow/streamer belt" estimate.