Difference of TEC daily variations deduced from global ionosphere maps of different laboratories, regional North-American TEC maps US-TEC and IRI model

Yasyukevich Yu.V., Ratovskiy K.G., Polyakova A.S., Sheifler A.A.
  1. Institute of Solar-Terrestrial Physics SB RAS

Nowadays ionosphere total electron content (TEC) mapping technique is widely adopted. On the basis of this
data it is possible to study daily variations of TEC which is of interest for ionosphere physics. Global ionosphere
maps (GIM) allow us to evaluate the amplitude of daily variations, maximal and minimal TEC value, rate of
ionization increasing near the solar terminator in different regions of the Earth. Moreover there are regional
North-American ionosphere maps. However, GIM and US-TEC are calculated by different laboratories on the
basis of some techniques. Application of any techniques results in some errors and so it is interesting to compare
TEC daily variations from GIM of different laboratories and US-TEC. In the report we compare amplitude and
half-width of daily variations, rate of ionization increasing for different level of solar and geomagnetic activity.
The results are compared with IRI-2007 model data.