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Table 1 Measured and simulated parameters in Taiwan and the Czech Republic for the specific frequencies f 0

From: Ionospheric signatures of the April 25, 2015 Nepal earthquake and the relative role of compression and advection for Doppler sounding of infrasound in the ionosphere

   Taiwan (f 0 = 6.57 MHz) Czech Republic (f 0 = 3.59 MHz) Czech Republic (f 0 = 4.65 MHz) Czech Republic (f 0 = 7.04 MHz)
1 t D (s) 532.3 ± 7 449.2 ± 7 480.0 ± 8 548.8 ± 24
2 h M (km) 201.4 ± 5.1 146.4 ± 4 163.9 ± 5 209.3 ± 17
3 c S at h M (m/s) 754 ± 11 560 ± 17 626 ± 16 731 ± 32
4 h I (km) O-mode 229 ± 20 144 ± 10 178 ± 10 230 ± 10
5 h I (km) X-mode 214 ± 20 102 ± 5 157 ± 10 215 ± 10
6 RMS(f D )_max (Hz) 0.393 0.172 0.307 0.084
7 w A max (m/s) 27.7 8.64 11.89 2.14
8 w A + C max (m/s) 0.84 ± 0.42 0.28 ± 0.14 0.41 ± 0.2 0.088 ± 0.044
9 RMS(v z )_max (m/s) 3.95 × 10−3 0.087 × 10−3 0.087 × 10−3 0.087 × 10−3
10 w A /v z (7.16 ± 0.22) × 103 (106 ± 8.8) × 103 (130 ± 10.2) × 103 (30 ± 7.9) × 103
11 w A + C /v z (0.22 ± 0.11) × 103 (3.4 ± 1.7) × 103 (4.5 ± 2.2) × 103 (1.2 ± 0.6) × 103
12 w /v z (theor. max) (43.7 ± 3.0) × 103 (17.2 ± 1.8) × 103 (25.3 ± 2.6) × 103 (53.2 ± 13.6) × 103
13 w /v z (expected) (9.7 ± 1.7) × 103 (14.9 ± 1.0) × 103 (17.4 ± 0.3) × 103 (5.9 ± 6.2/4.1) × 103
  1. t D is the time delay between the seismic wave and observation of the related Doppler shift fluctuations f D , h M is the modeled height for the time t D , c S is the speed of sound, h I is the height derived from ionosonde measurements, w A , w A + C and w is the air particle oscillation velocity computed from Eqs. (7), (9), and (13), respectively (c S0 = 334 m/s in the Czech Republic and c S0 = 346 m/s in Taiwan, depending on air temperature on ground), and v z stands for the vertical velocity of ground surface motion