Assessment of Predictive Capabilities of L1 Monitors using Dst Index

Real-time solar wind measurements from L1 monitors allow space weather forecasters to make predictions between 15 minutes and an hour in advance. These warnings can be crucial in preserving the health and safety of astronauts and airplane passengers near the poles, and in preparing for events that affect satellites and electrical grids. Geomagnetic indices such as Disturbance Storm Time index (Dst) allow for a concise, standardized prediction and measurement system. For years, the Space Weather Prediction Center used ACE real-time solar wind data to develop its one-hour Dst forecasts, but has recently switched to primarily using DSCOVR data as its source. In this study, the performance of both orbiters in predicting Dst was assessed in an attempt to determine whether or not switching to DSCOVR data has resulted in improved forecasts. This assessment was performed by comparing Dst output from the satellites to Dst derived from ground-based magnetometers. The periods of study were chosen to encompass times when the satellites were close to each other, and when moderate to high activity was observed. Dst predictions were made using the Space Weather Modeling Framework, specifically using BATS-R-US, Ridley Ionosphere, and the Rice Convection Model.