I got in my publication around 30 TECU

To get a close guess, the easiest thing to do would be to sift through the Madrigal TEC maps (best candidate periods to search would be 1999-2003). There are challenges to that though, as there is always the possibility for anomalous TEC measurements due to phase leveling issues, bias issues, cycle slips, etc... The answer should be around or greater than 100TECU. Kutubuddin Ansari We've seen 30TECU even at high latitudes, so it's likely going to be much higher than that.

Thank you David R. Themens. I agree that would be a good way to come up with a value, but I've had lots of issues accessing Madrigal data in the past and figured there is likely something published already that I could simply refer to.

I've been looking at

Ionosphere Monitoring and Prediction Center Global One hour Forecast TEC Maps (https://impc.dlr.de/products/total-electron-content/forecast-tec/1-h-fc-tec-global/) and think 130 TECu would be a reasonable value.

Hi Alex,

The maximum that people are referring too was recorded by WAAS network. It's so cold "supertruth" data. Slant TEC can reach 350-400 TECU at low elevation angles. Please find below a link to a report describing this data. Of course, all what David is saying is absolutely valid. STEC values, especially at low elevation angles, are prone to multi-path effects, and the rest of the above mentioned inaccuracies. Nevertheless, in my opinion, 300 to 400 TECU in slant TEC can be considered a worst case scenario.

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080009512.pdf

Best regards,

Anton

Hello, depend on several factors, such as: solar activity, magnetic field, latitude, etc. Normally around 100 TECU.

It depends on geomagnetic latitude, solar activity and geomagnetics storms. Please check GIM-TEC maps from IGS data repository.

We've detect 53 TECU (see: Article A Comprehensive Analysis of Ionospheric Anomalies before the...