Forecast Verification of the 10.7 Centimeter Solar Flux and the Ap Daily Geomagnetic Activity Indices

摘要

Air Force Global Weather Central space environmental forecasts of the 10.7 centimeter solar radioflux index and the Ap daily average geomagnetic activity index were compared with persistence forecasts to check for accuracy and skill. One, two and three day forecasts were compared. The AFGWC forecasts were found to be more accurate and skillful than the persistence forecasts. The data base covered the period from 4 January 1971 through 29 April 1984. Statistics were calculated for the total data set and each individual year. Root mean square error and percentage of significant errors were used as measures of accuracy. A paired sign test was used to compare for skill. The test was run on significant errors and absolute errors. A significant error is when the difference between the forecast value and the verifying observed value (ie. the observation one, two or three days hence) is greater than ten. This thesis set out to do two things: to check the accuracy of AFGWC forecasts and persistence as a forecast and to conduct a test which would determine if the forecasters exhibited skill when compared to persistence as an unskilled forecasts.