Sprite-Attributed Infrasonic Chirps
During a particular night of May 1995 an unusual type of infrasonic signatures: few seconds in duration, rising in frequency from about 0.5 - 8 Hz was observed. Since the observations were associated with the passage of an intense thunderstorm area, it was plausible to assume that the phenomenon could be related to the thunderstorm activity. One possibility was that the infrasonic chirps were produced by the high-altitude transient luminous event such as a red sprite. That particular night was studied in detail and results were presented several years later (Liszka 2003, 2004). The occurrence of infrasonic emissions from sprites was recently confirmed by simultaneous optical observations of sprites and infrasound over Europe (Farges et al., 2005), the long-term trend of sprite-associated infrasound signatures has been studied using the data from the Swedish-Finnish Infrasound Network (Liszka and Hobara, 2006).
The present page contains results of observations of infrasonic chirps from Jämtön-station, where the chirps are most frequent. Approximate geographic coordinates of Jämtön station are: 65.8N, 22.5E.
The list of observations and the atlas of wavelet scalograms will be continuously updated.
References:
Farges, T., E. Blanc, A. Le Pichon, T. Neubert, and T. H. Allin, 2005, Identification of infrasound produced by sprites during the Sprite2003 campaign,
Geophys. Res. Lett., 32, doi:10.1029/2004GL021212
Liszka, L., 2003, On the Possible Infrasound Generation by Sprites. Paper presented at the AGU Fall Meeting, 2003, San Francisco.
Liszka, L., 2004, On the possible infrasound generation by sprites,
Journ. of Low Frequency Noise, Vibration and Active Control, 23, 85-93.
Liszka, L. and Hobara, Y., 2006, Sprite-attributed infrasonic chirps - their detection, occurrence and properties between 1994 and 2004, JASTP, 68, 1179-1188.
Time scale (in sec) of plots corresponding to the first 32 dilations:
| Dilation | Time scale (s) |
|---|
| 1 | 0.1112 |
| 2 | 0.1186507 |
| 3 | 0.1266007 |
| 4 | 0.1350833 |
| 5 | 0.1441342 |
| 6 | 0.1537917 |
| 7 | 0.1640961 |
| 8 | 0.175091 |
| 9 | 0.1868227 |
| 10 | 0.1993403 |
| 11 | 0.2126967 |
| 12 | 0.226948 |
| 13 | 0.2421542 |
| 14 | 0.2583792 |
| 15 | 0.2756914 |
| 16 | 0.2941635 |
| 17 | 0.3138733 |
| 18 | 0.3349037 |
| 19 | 0.3573432 |
| 20 | 0.3812862 |
| 21 | 0.4068335 |
| 22 | 0.4340925 |
| 23 | 0.463178 |
| 24 | 0.4942122 |
| 25 | 0.5273259 |
| 26 | 0.5626583 |
| 27 | 0.600358 |
| 28 | 0.6405837 |
| 29 | 0.6835046 |
| 30 | 0.7293015 |
| 31 | 0.7781668 |
| 32 | 0.8303062 |
Summary of infrasonic chirps data, explanation of columns:
| Column | Description |
|---|
| 1. | File name (without the first character which is the station name - here all "J") |
| 2. | Year |
| 3. | Month |
| 4. | Day |
| 5. | Time Z at the beginning of a chirp (UT in minutes after midnight) |
| 6. | Slope SL of the chirp in the time scale. elapsed time domain SL = HLEN/DIFF |
| 7. | Duration of the chirp in number of samples, HLEN |
| 8. | STARTD start dilation of the chirp; see the table of time scale values corresponding to each dilation number |
| 9. | DIFF, the difference between the last and first dilation number +1 |
| 10. | Time Z corresponding to the maximum cross-correlation between microphones within the array |
| 11. | Azimuth of arrival at the maximum cross-correlation |
| 12. | Phase velocity at the maximum cross-correlation |
| 13. | Average amplitude (in arbitrary A/D units) at the maximum cross-correlation |
| 14. | The maximum product of all 3 cross-correlations within the array |
List of observed chirps:
Col 1 2 3 4 5 6 7 8 9 10 11 12 13 14
5010336 1995 01 03 1086.965 4.7 52 24 11 1087.024 97.4 331.0 13747 0.5267
5011132 1995 01 11 962.856 8.1 65 30 8 962.915 99.6 330.2 16012 0.5523
5052638 1995 05 26 1151.940 8.3 58 16 7 1151.999 163.9 329.5 10697 0.5051
5052640 1995 05 26 1209.384 7.2 87 21 12 1209.399 161.8 331.6 7358 0.4943
5052640 1995 05 26 1218.834 6.8 82 22 12 1218.864 131.9 339.9 7052 0.3331
5052641 1995 05 26 1230.568 7.6 61 15 8 1230.568 164.1 329.4 7967 0.4745
5052641 1995 05 26 1239.119 7.5 97 19 13 1239.193 128.0 339.1 6818 0.2619
5052641 1995 05 26 1242.184 8.3 75 15 9 1242.258 163.1 330.4 6320 0.3793
5052641 1995 05 26 1243.594 8.2 74 21 9 1243.668 163.1 329.2 12205 0.5680
5052641 1995 05 26 1243.594 7.8 47 12 6 1243.668 163.1 329.2 12205 0.5680
5052641 1995 05 26 1244.687 6.6 46 24 7 1244.731 142.5 343.0 6075 0.3396
5052641 1995 05 26 1245.567 7.0 49 14 7 1245.581 163.1 328.1 12199 0.5303
5052641 1995 05 26 1246.794 7.8 70 16 9 1246.808 160.6 329.1 6376 0.3145
5052641 1995 05 26 1248.584 7.3 66 19 9 1248.614 127.6 348.8 5027 0.1608
5052641 1995 05 26 1249.246 7.0 42 11 6 1249.291 163.3 330.9 10817 0.4952
5052641 1995 05 26 1250.790 8.2 107 19 13 1250.819 163.6 328.9 15359 0.5665
5052641 1995 05 26 1257.700 5.9 53 16 9 1257.700 125.2 352.5 6305 0.2820
5052642 1995 05 26 1268.199 5.9 53 25 9 1268.244 131.2 329.5 11606 0.5368
5052642 1995 05 26 1268.781 6.5 39 15 6 1268.781 158.9 326.5 9967 0.3412
5052642 1995 05 26 1272.635 5.9 89 21 15 1272.665 158.9 330.4 9863 0.3632
5052642 1995 05 26 1277.643 5.3 48 17 9 1277.672 121.9 349.6 6996 0.3327
5052642 1995 05 26 1283.937 5.1 36 16 7 1283.937 122.4 349.9 6006 0.2213
5052643 1995 05 26 1290.768 6.0 54 21 9 1290.827 123.3 349.1 8194 0.4892
5052643 1995 05 26 1296.248 5.7 91 22 16 1296.248 134.5 333.8 7109 0.3521
5052643 1995 05 26 1302.235 4.7 80 23 17 1302.280 156.4 327.4 7326 0.3121
5052643 1995 05 26 1313.213 5.9 47 14 8 1313.257 118.3 351.7 8891 0.4036
5090300 1995 09 03 26.982 3.9 77 28 20 27.027 179.5 325.0 6170 0.5348
5090341 1995 09 03 1245.608 8.0 64 23 8 1245.668 184.2 327.5 5328 0.3696
5090341 1995 09 03 1247.642 6.3 95 23 15 1247.642 184.6 324.0 12779 0.6155
5090341 1995 09 03 1249.903 5.8 93 22 16 1249.903 184.7 327.0 11978 0.5013
5090342 1995 09 03 1270.729 5.2 62 20 12 1270.773 186.6 324.9 8312 0.4089
5090342 1995 09 03 1286.735 5.1 77 21 15 1286.750 185.6 328.5 6960 0.4273
5111632 1995 11 16 970.632 4.9 74 30 15 970.706 98.3 332.8 17245 0.5129
5112819 1995 11 28 586.185 2.7 48 29 18 586.230 195.3 304.0 12095 0.6147
5122032 1995 12 20 968.689 7.6 99 30 13 968.719 100.5 320.1 20654 0.6257
5122132 1995 12 21 982.099 6.1 98 30 16 982.129 99.4 315.4 16912 0.5759
6011724 1996 01 17 722.438 4.1 57 30 14 722.497 99.4 339.5 13675 0.5684
6020532 1996 02 05 967.332 4.8 62 30 13 967.332 98.5 340.7 11110 0.5684
6022018 1996 02 20 546.932 11.9 119 25 10 546.977 197.7 300.0 23212 0.5927
6022112 1996 02 21 371.554 4.0 48 26 12 371.613 197.7 307.3 10767 0.5229
6031318 1996 03 13 545.602 10.4 114 25 11 545.943 195.7 320.7 12466 0.4468
6031518 1996 03 15 544.380 5.7 86 24 15 544.572 169.2 321.7 19713 0.5729
6031518 1996 03 15 544.555 5.7 68 21 12 544.555 169.2 321.6 19977 0.5705
6031518 1996 03 15 545.201 5.4 86 24 16 545.231 169.1 321.3 18343 0.5483
6031520 1996 03 15 625.510 4.8 86 25 18 625.555 168.0 325.4 23037 0.6295
6031520 1996 03 15 625.546 4.7 47 17 10 625.828 168.1 326.0 18349 0.5935
6031520 1996 03 15 625.668 4.6 65 22 14 625.949 168.1 326.0 18349 0.5935
6031520 1996 03 15 625.825 4.7 84 24 18 625.869 168.0 325.9 18547 0.5927
6062021 1996 06 20 639.830 5.4 76 28 14 639.874 176.8 315.2 11322 0.4952
6062030 1996 06 20 914.754 5.8 46 14 8 914.754 170.9 325.4 5508 0.2430
6062031 1996 06 20 948.906 4.4 53 18 12 948.951 155.4 324.9 11128 0.4268
7060615 1997 06 06 456.588 4.9 64 30 13 456.618 184.1 320.8 14736 0.5118
7122323 1997 12 23 715.964 7.3 66 26 9 716.231 98.2 333.9 16841 0.5901
7122323 1997 12 23 716.192 7.0 84 28 12 716.251 97.9 335.0 18885 0.5884
8011209 1998 01 12 275.240 4.3 47 29 11 275.314 101.3 328.7 9470 0.5864
8012024 1998 01 20 736.331 8.2 74 23 9 736.390 122.4 320.4 16765 0.5084
8012035 1998 01 20 1069.312 3.3 50 29 15 1069.342 199.7 302.6 13118 0.5715
8020124 1998 02 01 732.651 4.3 43 27 10 732.666 205.8 301.0 9228 0.6017
8020124 1998 02 01 733.622 4.8 43 27 9 733.637 205.6 305.0 9608 0.6204
8020133 1998 02 01 1003.156 5.2 52 26 10 1003.201 205.8 295.4 7058 0.4958
8020133 1998 02 01 1005.331 5.8 58 25 10 1005.345 205.6 303.2 7804 0.5796
8020133 1998 02 01 1005.685 5.0 60 27 12 1006.026 205.6 294.8 10335 0.6128
8020133 1998 02 01 1005.986 5.5 60 26 11 1006.060 206.2 294.3 10392 0.6316
8020133 1998 02 01 1006.063 5.2 57 26 11 1006.122 206.1 295.2 10026 0.6267
8020133 1998 02 01 1006.145 5.7 51 26 9 1006.160 206.0 296.0 9876 0.6376
8062745 1998 06 27 1369.304 6.9 90 25 13 1369.348 176.7 320.8 4027 0.2414
8071229 1998 07 12 873.598 4.0 48 19 12 873.657 125.8 349.6 4972 0.2302
8071229 1998 07 12 893.689 3.8 45 22 12 893.719 134.8 343.8 5750 0.3400
8071230 1998 07 12 903.500 3.7 66 24 18 903.544 165.4 332.7 13022 0.5765
8071230 1998 07 12 907.160 3.5 35 18 10 907.190 131.9 345.3 8507 0.3734
8071230 1998 07 12 913.517 3.7 44 19 12 913.531 132.9 340.9 6930 0.2969
8071230 1998 07 12 916.085 2.6 37 20 14 916.159 145.4 348.5 8986 0.3869
9011101 1999 01 11 44.193 5.0 60 26 12 44.207 196.1 338.3 6432 0.6673
9012723 1999 01 27 717.681 6.8 81 27 12 717.756 117.9 297.7 9047 0.6279
9012724 1999 01 27 737.908 8.3 58 26 7 737.938 117.7 296.2 8321 0.6616
9021021 1999 02 10 649.691 7.0 77 28 11 649.720 154.7 336.4 5808 0.5856
9021025 1999 02 10 759.278 4.9 44 24 9 759.278 169.6 341.6 18088 0.4593
9021125 1999 02 11 758.358 7.1 50 26 7 758.447 175.0 340.6 6033 0.5721
9031224 1999 03 12 737.358 4.3 47 30 11 737.388 178.0 342.8 11599 0.6517
9041425 1999 04 14 773.202 6.6 59 23 9 773.202 176.6 342.7 5243 0.5606
9042125 1999 04 21 762.791 9.9 79 30 8 762.806 172.9 370.4 6955 0.4007
9060423 1999 06 04 703.586 3.6 50 24 14 703.631 176.3 340.9 3559 0.4563
0062128 2000 06 21 854.671 6.6 59 15 9 854.686 183.5 345.6 5230 0.3280
0062632 2000 06 26 988.291 3.9 58 25 15 988.320 140.5 331.5 3922 0.3077
0100925 2000 10 09 768.451 6.1 79 24 13 768.481 185.1 353.9 14410 0.5072
1022732 2001 02 27 987.495 7.4 52 27 7 987.540 92.6 298.4 13739 0.6284
1031611 2001 03 16 338.111 3.6 36 25 10 338.111 40.8 314.6 3365 0.4705
1031611 2001 03 16 344.952 4.7 52 28 11 344.952 39.5 321.1 14445 0.4966
1040515 2001 04 05 467.983 5.5 55 25 10 468.072 162.2 342.6 17189 0.5530
1040515 2001 04 05 468.071 6.1 55 25 9 468.071 162.3 343.3 17161 0.5725
1040517 2001 04 05 527.469 4.5 63 26 14 527.558 165.6 339.3 21108 0.5126
1040517 2001 04 05 527.944 7.0 77 25 11 528.004 164.4 340.8 18661 0.6236
1042317 2001 04 23 530.106 5.9 77 20 13 530.135 167.9 339.0 5984 0.5052
1042421 2001 04 24 659.667 5.2 57 17 11 659.741 167.8 334.1 3645 0.3982
1042638 2001 04 26 1159.511 5.1 56 21 11 1159.526 105.0 322.0 3475 0.3807
1060824 2001 06 08 734.840 6.8 68 25 10 734.869 158.7 349.9 11461 0.4984
1071120 2001 07 11 625.320 4.1 45 17 11 625.350 150.3 365.5 8746 0.5253
1071120 2001 07 11 628.881 4.2 51 18 12 628.910 148.5 361.3 7193 0.5643
1121420 2001 12 14 620.050 5.7 57 30 10 620.109 103.2 303.3 13675 0.6269
2012828 2002 01 28 847.210 5.1 36 28 7 847.240 203.1 363.7 2916 0.2626
2012828 2002 01 28 848.891 4.6 37 28 8 848.920 199.5 339.9 3052 0.2660
2012828 2002 01 28 850.328 3.9 39 26 10 850.387 203.8 346.9 3074 0.2645
2012828 2002 01 28 852.189 3.8 45 27 12 852.219 205.0 342.5 3171 0.3308
2012828 2002 01 28 855.020 4.4 35 27 8 855.080 203.2 329.1 3308 0.2932
2012828 2002 01 28 856.407 4.0 36 26 9 856.422 206.1 335.7 3426 0.3410
2012828 2002 01 28 857.745 4.6 37 25 8 857.760 205.3 334.8 3420 0.3157
2012828 2002 01 28 859.055 4.0 44 27 11 859.084 203.9 342.9 3527 0.2421
2012828 2002 01 28 860.741 5.1 36 26 7 860.770 205.8 336.2 3483 0.3279
2012828 2002 01 28 863.226 3.8 42 27 11 863.256 203.3 332.0 3521 0.2973
2012828 2002 01 28 864.528 3.7 44 28 12 864.557 205.5 325.2 3672 0.3485
2051514 2002 05 15 438.044 6.6 53 17 8 438.118 169.9 347.9 14183 0.2332
2051516 2002 05 15 504.201 5.7 80 20 14 504.290 165.7 344.2 17894 0.4315
2070524 2002 07 05 735.569 5.6 95 30 17 735.614 181.0 356.6 11207 0.6585
3041201 2003 04 12 44.665 6.9 69 20 10 44.709 142.6 344.2 8921 0.3743
3041201 2003 04 12 44.808 7.0 63 20 9 44.808 139.6 343.1 8502 0.3688
3051314 2003 05 13 446.310 7.0 49 18 7 446.606 165.4 348.9 9853 0.5242
3051419 2003 05 14 586.158 7.2 65 30 9 586.218 166.8 365.5 8848 0.5421
3112542 2003 11 25 1264.219 5.9 71 30 12 1264.279 89.7 276.5 9051 0.6057
4042015 2004 04 20 461.937 4.0 56 22 14 461.952 165.4 344.8 8023 0.4688
4050413 2004 05 04 410.332 8.1 73 16 9 410.406 164.4 344.7 10211 0.4147
4050712 2004 05 07 361.883 7.6 99 19 13 361.913 164.2 346.0 6773 0.4822
4122733 2004 12 27 1019.442 2.4 39 26 16 1019.501 196.1 350.6 7065 0.4707
5013136 2005 01 31 1089.182 2.8 39 25 14 1089.182 195.9 350.9 8108 0.4649
5050524 2005 05 05 749.139 7.0 112 22 16 749.183 163.8 347.1 13046 0.4508
5120118 2005 12 01 552.316 5.2 57 29 11 552.331 207.8 378.8 4063 0.3783
6011011 2006 01 10 337.031 3.3 49 28 15 337.120 194.5 351.8 8556 0.5598
6021117 2006 02 11 527.925 6.3 69 29 11 527.955 202.2 415.0 4076 0.2415
6021118 2006 02 11 552.428 4.8 58 27 12 552.457 202.0 392.5 3917 0.2995
6021119 2006 02 11 594.301 3.8 64 30 17 594.345 204.3 407.9 4032 0.3081
6021216 2006 02 12 502.456 6.4 58 25 9 502.456 200.5 421.3 3788 0.2984
6021417 2006 02 14 513.943 5.1 41 25 8 513.957 206.9 362.2 4590 0.2090
6021417 2006 02 14 536.319 6.3 44 25 7 536.333 201.6 397.8 4243 0.1509
6021420 2006 02 14 608.206 5.6 50 26 9 608.220 198.3 365.2 3952 0.2084
6021420 2006 02 14 610.330 6.2 37 24 6 610.344 205.2 351.6 4255 0.3329
6021421 2006 02 14 645.964 6.1 43 25 7 646.038 204.8 325.5 3775 0.1787
6022122 2006 02 21 671.306 3.0 42 26 14 671.306 257.6 373.0 6613 0.5051
6030323 2006 03 03 706.510 3.8 42 30 11 706.510 179.6 357.2 7164 0.5505
6030326 2006 03 03 790.055 6.6 53 29 8 790.099 163.6 345.1 4050 0.2105
6030416 2006 03 04 483.409 3.7 41 22 11 483.409 156.2 336.0 5922 0.3960
6032712 2006 03 27 376.028 6.6 46 18 7 376.087 139.5 335.6 4840 0.3771
6042513 2006 04 25 400.453 4.0 48 19 12 400.453 165.4 338.2 9973 0.4913
6042526 2006 04 25 804.569 6.7 67 21 10 804.584 166.4 352.0 9698 0.3844
6042613 2006 04 26 398.985 8.6 103 18 12 398.985 168.0 341.5 11617 0.3759
6042812 2006 04 28 383.834 7.9 127 23 16 383.879 166.1 337.1 13366 0.5021
6043012 2006 04 30 376.850 7.5 60 14 8 376.850 168.6 343.6 6815 0.3016
6050212 2006 05 02 377.050 9.7 155 22 16 377.050 163.9 359.6 12815 0.4456
6050417 2006 05 04 519.289 4.7 47 17 10 519.319 164.2 344.9 6974 0.5202
7022322 2007 02 23 674.395 11.6 93 30 8 674.455 164.5 350.9 3700 0.6410
7022324 2007 02 23 749.596 8.4 143 30 17 749.907 180.7 330.8 7120 0.4798
7030526 2007 03 05 782.537 6.9 62 30 9 782.552 163.0 338.2 7835 0.6088
7051525 2007 05 15 777.601 3.3 40 20 12 777.645 152.8 353.1 5805 0.4100
8042919 2008 04 29 598.651 4.7 47 16 10 598.695 166.5 340.4 3960 0.5598
8050112 2008 05 01 388.550 9.1 73 14 8 388.580 165.2 342.0 5036 0.5567
8050119 2008 05 01 598.612 6.5 72 18 11 598.627 166.3 343.9 2770 0.4560
8050125 2008 05 01 779.687 7.7 77 19 10 779.820 165.7 344.3 4199 0.5554
9021146 2009 02 11 1398.660 3.6 57 29 16 1398.705 195.8 339.8 5491 0.6640
9022024 2009 02 20 738.589 4.9 59 30 12 738.633 181.1 360.8 10033 0.6104
9032702 2009 03 27 61.031 4.2 42 26 10 61.090 195.0 336.8 1339 0.1856
9040933 2009 04 09 992.756 9.7 58 29 6 992.800 160.5 361.2 2852 0.3060
9042617 2009 04 26 522.875 7.0 42 12 6 522.919 166.7 342.9 2973 0.4288
9042712 2009 04 27 379.469 5.1 56 17 11 379.469 167.4 335.2 6287 0.5338
9042725 2009 04 27 775.431 5.4 43 14 8 775.445 166.9 337.8 5284 0.5448
9050230 2009 05 02 900.655 8.0 88 17 11 900.684 164.6 342.2 3063 0.4776
9052726 2009 05 27 795.966 6.9 90 22 13 795.981 163.7 352.8 5486 0.5642
Atlas of wavelet-scalograms
All scalogram are presented as dilation no. - sample no. graphs. The dilation no. may be converted to the time scale. The absolute time of each chirp may be obtained from the above table.
HTML by Jan Karlsson ( jk_&_irf_dot_se )
This page was updated
Tuesday, 10-Nov-2009 15:40:26 CET.
