GPS L1 Iono Error

Please Note:We are aware of the issue with the TEC map on this page. The plot is not functioning correctly. A fix is currently being investigated.

Updates: Every 60 minutes

This near-real-time map shows the estimated GPS positioning error, in metres of L1, resulting from the difference between the GPS broadcast Klobuchar model of ionospheric delay and the best current estimate of 'true' ionosheric delay, as observed by ASWFC.

It is therefore representative of the ionospheric contribution to GPS position error for single-frequency GPS, which at mid-latitudes typically ranges between 1 and 5m. Both enhancements and depressions of the ionosphere can result in reduced GPS positioning accuracy.

The map shows colour contours of position error at GPS L1 (ie single frequency), in units of metres.

This product is new and under ongoing development, and your feedback is valuable to us. If you have a comment on this product, or a suggestion on ways we may improve this product or our ionospheric services in general, please contact ASWFC.