Candidate models for the IGRF-11th generation making use of extrapolated observatory data

摘要

Three candidate models are produced in response to the call for IGRF-11 models. A main field model around epoch 2005.0 is based on one year of ?rsted and CHAMP measurements, and is proposed for the definitive model for epoch 2005.0. A main field model around epoch 2009.5, based on two months of CHAMP measurements and extrapolated to 2010.0, is proposed as a main field model for epoch 2010.0. A secular variation model valid for 2010.0-2015.0, based on the extrapolation through exponential smoothing of observatory monthly mean values, is proposed as a predictive secular variation model. Comparison of similar extrapolations made for previous IGRF generations with actual observations are presented and discussed.