SUDDEN ENHANCEMENTS OF ATMOSPHERICS - SEA Month: APRIL YEAR: 2007 Observing Station: OBSERVATORY U P I C E CZECH REPUBLIC Lat.: 50 30 26.6 N Sea level: 416 m Long.: 16 00 43.5 E Frequency: 27 kHz Band pass: 308 Hz a 3 dB Chart speed: 3.4 cm/H Recorder time constant: 27 sec Date Start End Max. Imp. Def. Dur. Type REMARKS UT UT UT SEA min. 1 0740 0804 0750 1 2 24 5 UNCERTN 8 0909 0948 0921 1 2 39 2a UNCERTN 1022 1051 1037 1 2 29 2b UNCERTN 12 1550 1626 1559 1 2 36 5 15 1445 1521 1501U 1 2 36 5 16 1658 1717 1703 1 2 19 2a 25 1029 1158 1037U 1 2 89 3 1214 1254 1241U 1 2 40 3 26 0930 1004 0937 1 2 34 3 1010 1121 1053 1 2 71 3 28 1640 1722 1652 1 2 42 5 29 1338 1456 1427U 1 2 78 3 1556 1616 1605 1 2 20 6 Evaluated by J.Klimes