Two types of positive disturbances in the daytime mid-latitude F2-layer: Morphology and formation mechanisms

► Two types of positive F2-layer disturbances with different morphology. ► Type I is referred to those followed by quiet or positively disturbed ionospheric conditions. ► Type II related to strong geomagnetic storms and followed by negative disturbances. ► Type II daytime are mainly produced by TADs and by disturbed equatorward winds. ► Type I shows that different aeronomic parameters may play the leading role.