EMMA magnetometer data for the April 2023 geomagnetic storm event

This data set contains daily files of 1-sec geomagnetic field variations from stations of the European quasi-Meridional Magnetometer Array (EMMA) recorded during the April 2023 geomagnetic storm event (namely, for the reference day, 17 April, and the period 22-26 April. Due to missing data, KIL is only included for 26 April and MUO only for 17 and 26 April). You can find more information on EMMA, including QuickLook plots at http://tihany.epss.hu/plasmon/. List of EMMA stations (April 2023), including their geodetic and magnetic coordinates (AACGM evaluated at 120 km altitutde), and the corresponding L-values Code Name geo. lat. (°) geo. long. (°) aacgm lat.* (°) cgm long. (°) L-value KEV Kevo 69.76 27.01 67.22 107.16 6.67 MAS Masi 69.46 23.70 67.01 104.21 6.56 KIL Kilpisjärvi 69.06 20.77 66.69 101.53 6.39 IVA Ivalo 68.56 27.29 66.00 106.67 6.05 MUO Muonio 68.02 23.53 65.55 103.20 5.84 SOD Sodankylä 67.37 26.63 64.81 105.46 5.52 PEL Pello 66.90 24.08 64.39 103.05 5.35 RAN Raniu 65.90 26.41 63.32 104.54 4.96 OUJ Oulujärvi 64.52 27.23 61.89 104.63 4.50 HAN Hankasalmi 62.25 26.60 59.55 103.20 3.89 NUR Nurmijärvi 60.50 24.65 57.75 100.88 3.51 TAR Tartu 58.26 26.46 55.39 101.81 3.10 BRZ Birzai 56.21 24.75 53.21 99.74 2.79 SUW Suwalki 54.01 23.18 50.82 97.80 2.51 BEL Belsk 51.83 20.80 48.40 95.18 2.27 ZAG Zagorzyce 50.28 20.58 46.67 94.68 2.12 VYH Vyhne 48.49 18.84 44.59 92.77 1.97 THY Tihany 46.90 17.89 42.73 91.64 1.85 CST Castello Tesino 46.05 11.65 41.46 85.90 1.78 LOP Lonjsko Polje 45.41 16.66 40.83 90.38 1.75 RNC Ranchio 43.97 12.08 38.95 85.94 1.65 AQU L'Aquila 42.38 13.32 37.08 86.82 1.57