# PURPOSE: This file distributes the Kp index and ap index (one line per three-hour interval) # LICENSE: CC BY 4.0 # SOURCE: Geomagnetic Observatory Niemegk, GFZ Helmholtz Centre for Geosciences # PLEASE CITE: Matzka, J., Stolle, C., Yamazaki, Y., Bronkalla, O. and Morschhauser, A., 2021. The geomagnetic Kp index # and derived indices of geomagnetic activity. Space Weather, https://doi.org/10.1029/2020SW002641 # # Kp, ap and Ap # The three-hourly equivalent planetary amplitude ap is derived from Kp and the daily equivalent planetary amplitude Ap is the daily mean of ap. # Kp is unitless. Ap and ap are unitless and can be multiplied by 2 nT to yield the average geomagnetic disturbance at 50 degree geomagnetic latitude. # Kp, ap and Ap were introduced by Bartels (1949, 1957) and are produced by Geomagnetic Observatory Niemegk, GFZ Helmholtz Centre for Geosciences. # Described in: Matzka et al. (2021), see reference above. # Data publication: Matzka, J., Bronkalla, O., Tornow, K., Elger, K. and Stolle, C., 2021. Geomagnetic Kp index. V. 1.0. GFZ Data Services, # https://doi.org/10.5880/Kp.0001 # # Short file description (for a detailed file description, see Kp_ap_Ap_SN_F107_format.txt): # 30 header lines, all starting with # # ASCII, blank separated and fixed length, missing data indicated by -1.000 for Kp and -1 for ap # YYYY MM DD is date of UT day, hh.h is starting time in hours of interval for which Kp and ap are given # hh._m is mid time in hours of interval for which Kp and ap are given # days is days since 1932-01-01 00:00 UT to start of interval, days_m is days since 1932-01-01 00:00 UT to mid of interval # Kp, ap # D indicates if the Kp and ap values are definitive (D = 1) or preliminary (D=0) # # # # # The format for each line is (i stands for integer, f for float): #iii ii ii ff.f ff.ff fffff.fffff fffff.fffff ff.fff iiii i # The parameters in each line are: #YYY MM DD hh.h hh._m days days_m Kp ap D 2026 04 28 00.0 01.50 34451.00000 34451.06250 0.000 0 1 2026 04 28 03.0 04.50 34451.12500 34451.18750 0.667 3 1 2026 04 28 06.0 07.50 34451.25000 34451.31250 0.000 0 1 2026 04 28 09.0 10.50 34451.37500 34451.43750 0.333 2 1 2026 04 28 12.0 13.50 34451.50000 34451.56250 0.667 3 1 2026 04 28 15.0 16.50 34451.62500 34451.68750 0.667 3 1 2026 04 28 18.0 19.50 34451.75000 34451.81250 1.333 5 1 2026 04 28 21.0 22.50 34451.87500 34451.93750 0.000 0 1 2026 04 29 00.0 01.50 34452.00000 34452.06250 0.000 0 1 2026 04 29 03.0 04.50 34452.12500 34452.18750 0.000 0 1 2026 04 29 06.0 07.50 34452.25000 34452.31250 0.333 2 1 2026 04 29 09.0 10.50 34452.37500 34452.43750 0.667 3 1 2026 04 29 12.0 13.50 34452.50000 34452.56250 1.333 5 1 2026 04 29 15.0 16.50 34452.62500 34452.68750 0.333 2 1 2026 04 29 18.0 19.50 34452.75000 34452.81250 1.667 6 1 2026 04 29 21.0 22.50 34452.87500 34452.93750 1.333 5 1 2026 04 30 00.0 01.50 34453.00000 34453.06250 2.000 7 1 2026 04 30 03.0 04.50 34453.12500 34453.18750 1.333 5 1 2026 04 30 06.0 07.50 34453.25000 34453.31250 0.667 3 1 2026 04 30 09.0 10.50 34453.37500 34453.43750 1.667 6 1 2026 04 30 12.0 13.50 34453.50000 34453.56250 2.333 9 1 2026 04 30 15.0 16.50 34453.62500 34453.68750 2.667 12 1 2026 04 30 18.0 19.50 34453.75000 34453.81250 4.000 27 1 2026 04 30 21.0 22.50 34453.87500 34453.93750 4.667 39 1 2026 05 01 00.0 01.50 34454.00000 34454.06250 3.667 22 0 2026 05 01 03.0 04.50 34454.12500 34454.18750 4.333 32 0 2026 05 01 06.0 07.50 34454.25000 34454.31250 3.000 15 0 2026 05 01 09.0 10.50 34454.37500 34454.43750 1.333 5 0 2026 05 01 12.0 13.50 34454.50000 34454.56250 0.667 3 0 2026 05 01 15.0 16.50 34454.62500 34454.68750 1.667 6 0 2026 05 01 18.0 19.50 34454.75000 34454.81250 3.000 15 0 2026 05 01 21.0 22.50 34454.87500 34454.93750 1.333 5 0 2026 05 02 00.0 01.50 34455.00000 34455.06250 2.333 9 0 2026 05 02 03.0 04.50 34455.12500 34455.18750 1.333 5 0 2026 05 02 06.0 07.50 34455.25000 34455.31250 0.667 3 0 2026 05 02 09.0 10.50 34455.37500 34455.43750 1.667 6 0 2026 05 02 12.0 13.50 34455.50000 34455.56250 1.333 5 0 2026 05 02 15.0 16.50 34455.62500 34455.68750 1.000 4 0 2026 05 02 18.0 19.50 34455.75000 34455.81250 1.333 5 0 2026 05 02 21.0 22.50 34455.87500 34455.93750 2.667 12 0 2026 05 03 00.0 01.50 34456.00000 34456.06250 3.333 18 0 2026 05 03 03.0 04.50 34456.12500 34456.18750 2.333 9 0 2026 05 03 06.0 07.50 34456.25000 34456.31250 2.333 9 0 2026 05 03 09.0 10.50 34456.37500 34456.43750 0.667 3 0 2026 05 03 12.0 13.50 34456.50000 34456.56250 1.333 5 0 2026 05 03 15.0 16.50 34456.62500 34456.68750 2.667 12 0 2026 05 03 18.0 19.50 34456.75000 34456.81250 1.333 5 0 2026 05 03 21.0 22.50 34456.87500 34456.93750 1.000 4 0 2026 05 04 00.0 01.50 34457.00000 34457.06250 1.667 6 0 2026 05 04 03.0 04.50 34457.12500 34457.18750 2.000 7 0 2026 05 04 06.0 07.50 34457.25000 34457.31250 1.667 6 0 2026 05 04 09.0 10.50 34457.37500 34457.43750 2.667 12 0 2026 05 04 12.0 13.50 34457.50000 34457.56250 2.667 12 0 2026 05 04 15.0 16.50 34457.62500 34457.68750 4.000 27 0 2026 05 04 18.0 19.50 34457.75000 34457.81250 5.333 56 0 2026 05 04 21.0 22.50 34457.87500 34457.93750 4.333 32 0 2026 05 05 00.0 01.50 34458.00000 34458.06250 4.667 39 0 2026 05 05 03.0 04.50 34458.12500 34458.18750 3.667 22 0 2026 05 05 06.0 07.50 34458.25000 34458.31250 1.667 6 0 2026 05 05 09.0 10.50 34458.37500 34458.43750 1.000 4 0 2026 05 05 12.0 13.50 34458.50000 34458.56250 0.667 3 0 2026 05 05 15.0 16.50 34458.62500 34458.68750 0.333 2 0 2026 05 05 18.0 19.50 34458.75000 34458.81250 0.667 3 0 2026 05 05 21.0 22.50 34458.87500 34458.93750 1.000 4 0 2026 05 06 00.0 01.50 34459.00000 34459.06250 0.333 2 0 2026 05 06 03.0 04.50 34459.12500 34459.18750 0.000 0 0 2026 05 06 06.0 07.50 34459.25000 34459.31250 0.667 3 0 2026 05 06 09.0 10.50 34459.37500 34459.43750 0.333 2 0 2026 05 06 12.0 13.50 34459.50000 34459.56250 0.333 2 0 2026 05 06 15.0 16.50 34459.62500 34459.68750 0.667 3 0 2026 05 06 18.0 19.50 34459.75000 34459.81250 0.667 3 0 2026 05 06 21.0 22.50 34459.87500 34459.93750 0.667 3 0 2026 05 07 00.0 01.50 34460.00000 34460.06250 0.667 3 0 2026 05 07 03.0 04.50 34460.12500 34460.18750 0.667 3 0 2026 05 07 06.0 07.50 34460.25000 34460.31250 0.000 0 0 2026 05 07 09.0 10.50 34460.37500 34460.43750 0.333 2 0 2026 05 07 12.0 13.50 34460.50000 34460.56250 0.333 2 0 2026 05 07 15.0 16.50 34460.62500 34460.68750 3.333 18 0 2026 05 07 18.0 19.50 34460.75000 34460.81250 3.667 22 0 2026 05 07 21.0 22.50 34460.87500 34460.93750 2.000 7 0 2026 05 08 00.0 01.50 34461.00000 34461.06250 2.333 9 0 2026 05 08 03.0 04.50 34461.12500 34461.18750 1.000 4 0 2026 05 08 06.0 07.50 34461.25000 34461.31250 2.000 7 0 2026 05 08 09.0 10.50 34461.37500 34461.43750 3.333 18 0 2026 05 08 12.0 13.50 34461.50000 34461.56250 3.333 18 0 2026 05 08 15.0 16.50 34461.62500 34461.68750 3.667 22 0 2026 05 08 18.0 19.50 34461.75000 34461.81250 2.000 7 0 2026 05 08 21.0 22.50 34461.87500 34461.93750 3.000 15 0 2026 05 09 00.0 01.50 34462.00000 34462.06250 2.333 9 0 2026 05 09 03.0 04.50 34462.12500 34462.18750 1.333 5 0 2026 05 09 06.0 07.50 34462.25000 34462.31250 0.667 3 0 2026 05 09 09.0 10.50 34462.37500 34462.43750 1.333 5 0 2026 05 09 12.0 13.50 34462.50000 34462.56250 0.667 3 0 2026 05 09 15.0 16.50 34462.62500 34462.68750 1.333 5 0 2026 05 09 18.0 19.50 34462.75000 34462.81250 0.667 3 0 2026 05 09 21.0 22.50 34462.87500 34462.93750 0.667 3 0 2026 05 10 00.0 01.50 34463.00000 34463.06250 0.000 0 0 2026 05 10 03.0 04.50 34463.12500 34463.18750 0.667 3 0 2026 05 10 06.0 07.50 34463.25000 34463.31250 1.000 4 0 2026 05 10 09.0 10.50 34463.37500 34463.43750 0.667 3 0 2026 05 10 12.0 13.50 34463.50000 34463.56250 1.333 5 0 2026 05 10 15.0 16.50 34463.62500 34463.68750 1.333 5 0 2026 05 10 18.0 19.50 34463.75000 34463.81250 2.000 7 0 2026 05 10 21.0 22.50 34463.87500 34463.93750 1.000 4 0 2026 05 11 00.0 01.50 34464.00000 34464.06250 2.000 7 0 2026 05 11 03.0 04.50 34464.12500 34464.18750 1.333 5 0 2026 05 11 06.0 07.50 34464.25000 34464.31250 0.667 3 0 2026 05 11 09.0 10.50 34464.37500 34464.43750 0.667 3 0 2026 05 11 12.0 13.50 34464.50000 34464.56250 1.667 6 0 2026 05 11 15.0 16.50 34464.62500 34464.68750 1.000 4 0 2026 05 11 18.0 19.50 34464.75000 34464.81250 1.000 4 0 2026 05 11 21.0 22.50 34464.87500 34464.93750 0.667 3 0 2026 05 12 00.0 01.50 34465.00000 34465.06250 0.667 3 0 2026 05 12 03.0 04.50 34465.12500 34465.18750 0.667 3 0 2026 05 12 06.0 07.50 34465.25000 34465.31250 0.667 3 0 2026 05 12 09.0 10.50 34465.37500 34465.43750 0.333 2 0 2026 05 12 12.0 13.50 34465.50000 34465.56250 0.667 3 0 2026 05 12 15.0 16.50 34465.62500 34465.68750 0.667 3 0 2026 05 12 18.0 19.50 34465.75000 34465.81250 1.333 5 0 2026 05 12 21.0 22.50 34465.87500 34465.93750 0.667 3 0 2026 05 13 00.0 01.50 34466.00000 34466.06250 0.667 3 0 2026 05 13 03.0 04.50 34466.12500 34466.18750 1.333 5 0 2026 05 13 06.0 07.50 34466.25000 34466.31250 1.000 4 0 2026 05 13 09.0 10.50 34466.37500 34466.43750 1.333 5 0 2026 05 13 12.0 13.50 34466.50000 34466.56250 3.000 15 0 2026 05 13 15.0 16.50 34466.62500 34466.68750 3.000 15 0 2026 05 13 18.0 19.50 34466.75000 34466.81250 3.000 15 0 2026 05 13 21.0 22.50 34466.87500 34466.93750 3.333 18 0 2026 05 14 00.0 01.50 34467.00000 34467.06250 2.667 12 0 2026 05 14 03.0 04.50 34467.12500 34467.18750 1.333 5 0 2026 05 14 06.0 07.50 34467.25000 34467.31250 1.333 5 0 2026 05 14 09.0 10.50 34467.37500 34467.43750 0.667 3 0 2026 05 14 12.0 13.50 34467.50000 34467.56250 0.667 3 0 2026 05 14 15.0 16.50 34467.62500 34467.68750 0.667 3 0 2026 05 14 18.0 19.50 34467.75000 34467.81250 0.667 3 0 2026 05 14 21.0 22.50 34467.87500 34467.93750 1.000 4 0 2026 05 15 00.0 01.50 34468.00000 34468.06250 2.333 9 0 2026 05 15 03.0 04.50 34468.12500 34468.18750 1.667 6 0 2026 05 15 06.0 07.50 34468.25000 34468.31250 3.000 15 0 2026 05 15 09.0 10.50 34468.37500 34468.43750 3.667 22 0 2026 05 15 12.0 13.50 34468.50000 34468.56250 5.000 48 0 2026 05 15 15.0 16.50 34468.62500 34468.68750 4.667 39 0 2026 05 15 18.0 19.50 34468.75000 34468.81250 4.333 32 0 2026 05 15 21.0 22.50 34468.87500 34468.93750 6.000 80 0 2026 05 16 00.0 01.50 34469.00000 34469.06250 5.667 67 0 2026 05 16 03.0 04.50 34469.12500 34469.18750 4.667 39 0 2026 05 16 06.0 07.50 34469.25000 34469.31250 4.667 39 0 2026 05 16 09.0 10.50 34469.37500 34469.43750 4.000 27 0 2026 05 16 12.0 13.50 34469.50000 34469.56250 2.667 12 0 2026 05 16 15.0 16.50 34469.62500 34469.68750 4.333 32 0 2026 05 16 18.0 19.50 34469.75000 34469.81250 3.000 15 0 2026 05 16 21.0 22.50 34469.87500 34469.93750 3.333 18 0 2026 05 17 00.0 01.50 34470.00000 34470.06250 2.000 7 0 2026 05 17 03.0 04.50 34470.12500 34470.18750 2.000 7 0 2026 05 17 06.0 07.50 34470.25000 34470.31250 2.000 7 0 2026 05 17 09.0 10.50 34470.37500 34470.43750 2.333 9 0 2026 05 17 12.0 13.50 34470.50000 34470.56250 2.000 7 0 2026 05 17 15.0 16.50 34470.62500 34470.68750 1.667 6 0 2026 05 17 18.0 19.50 34470.75000 34470.81250 2.000 7 0 2026 05 17 21.0 22.50 34470.87500 34470.93750 1.667 6 0 2026 05 18 00.0 01.50 34471.00000 34471.06250 2.333 9 0 2026 05 18 03.0 04.50 34471.12500 34471.18750 2.000 7 0 2026 05 18 06.0 07.50 34471.25000 34471.31250 2.333 9 0 2026 05 18 09.0 10.50 34471.37500 34471.43750 1.333 5 0 2026 05 18 12.0 13.50 34471.50000 34471.56250 2.333 9 0 2026 05 18 15.0 16.50 34471.62500 34471.68750 2.000 7 0 2026 05 18 18.0 19.50 34471.75000 34471.81250 2.000 7 0 2026 05 18 21.0 22.50 34471.87500 34471.93750 3.000 15 0 2026 05 19 00.0 01.50 34472.00000 34472.06250 1.667 6 0 2026 05 19 03.0 04.50 34472.12500 34472.18750 2.667 12 0 2026 05 19 06.0 07.50 34472.25000 34472.31250 3.333 18 0 2026 05 19 09.0 10.50 34472.37500 34472.43750 3.333 18 0 2026 05 19 12.0 13.50 34472.50000 34472.56250 4.000 27 0 2026 05 19 15.0 16.50 34472.62500 34472.68750 3.667 22 0 2026 05 19 18.0 19.50 34472.75000 34472.81250 3.000 15 0 2026 05 19 21.0 22.50 34472.87500 34472.93750 3.000 15 0 2026 05 20 00.0 01.50 34473.00000 34473.06250 3.333 18 0 2026 05 20 03.0 04.50 34473.12500 34473.18750 2.667 12 0 2026 05 20 06.0 07.50 34473.25000 34473.31250 1.333 5 0 2026 05 20 09.0 10.50 34473.37500 34473.43750 0.667 3 0 2026 05 20 12.0 13.50 34473.50000 34473.56250 1.333 5 0 2026 05 20 15.0 16.50 34473.62500 34473.68750 1.000 4 0 2026 05 20 18.0 19.50 34473.75000 34473.81250 1.333 5 0 2026 05 20 21.0 22.50 34473.87500 34473.93750 2.333 9 0 2026 05 21 00.0 01.50 34474.00000 34474.06250 2.667 12 0 2026 05 21 03.0 04.50 34474.12500 34474.18750 2.000 7 0 2026 05 21 06.0 07.50 34474.25000 34474.31250 1.000 4 0 2026 05 21 09.0 10.50 34474.37500 34474.43750 1.333 5 0 2026 05 21 12.0 13.50 34474.50000 34474.56250 2.000 7 0 2026 05 21 15.0 16.50 34474.62500 34474.68750 1.000 4 0 2026 05 21 18.0 19.50 34474.75000 34474.81250 1.667 6 0 2026 05 21 21.0 22.50 34474.87500 34474.93750 1.333 5 0 2026 05 22 00.0 01.50 34475.00000 34475.06250 1.000 4 0 2026 05 22 03.0 04.50 34475.12500 34475.18750 1.333 5 0 2026 05 22 06.0 07.50 34475.25000 34475.31250 1.000 4 0 2026 05 22 09.0 10.50 34475.37500 34475.43750 1.333 5 0 2026 05 22 12.0 13.50 34475.50000 34475.56250 0.333 2 0 2026 05 22 15.0 16.50 34475.62500 34475.68750 0.667 3 0 2026 05 22 18.0 19.50 34475.75000 34475.81250 0.667 3 0 2026 05 22 21.0 22.50 34475.87500 34475.93750 2.333 9 0 2026 05 23 00.0 01.50 34476.00000 34476.06250 0.333 2 0 2026 05 23 03.0 04.50 34476.12500 34476.18750 0.667 3 0 2026 05 23 06.0 07.50 34476.25000 34476.31250 1.000 4 0 2026 05 23 09.0 10.50 34476.37500 34476.43750 0.333 2 0 2026 05 23 12.0 13.50 34476.50000 34476.56250 0.333 2 0 2026 05 23 15.0 16.50 34476.62500 34476.68750 0.000 0 0 2026 05 23 18.0 19.50 34476.75000 34476.81250 0.000 0 0 2026 05 23 21.0 22.50 34476.87500 34476.93750 0.333 2 0 2026 05 24 00.0 01.50 34477.00000 34477.06250 0.667 3 0 2026 05 24 03.0 04.50 34477.12500 34477.18750 0.667 3 0 2026 05 24 06.0 07.50 34477.25000 34477.31250 1.000 4 0 2026 05 24 09.0 10.50 34477.37500 34477.43750 1.000 4 0 2026 05 24 12.0 13.50 34477.50000 34477.56250 1.667 6 0 2026 05 24 15.0 16.50 34477.62500 34477.68750 1.000 4 0 2026 05 24 18.0 19.50 34477.75000 34477.81250 1.667 6 0 2026 05 24 21.0 22.50 34477.87500 34477.93750 1.667 6 0 2026 05 25 00.0 01.50 34478.00000 34478.06250 2.667 12 0 2026 05 25 03.0 04.50 34478.12500 34478.18750 1.667 6 0 2026 05 25 06.0 07.50 34478.25000 34478.31250 1.000 4 0 2026 05 25 09.0 10.50 34478.37500 34478.43750 1.667 6 0 2026 05 25 12.0 13.50 34478.50000 34478.56250 1.667 6 0 2026 05 25 15.0 16.50 34478.62500 34478.68750 2.000 7 0 2026 05 25 18.0 19.50 34478.75000 34478.81250 2.000 7 0 2026 05 25 21.0 22.50 34478.87500 34478.93750 2.667 12 0 2026 05 26 00.0 01.50 34479.00000 34479.06250 2.000 7 0 2026 05 26 03.0 04.50 34479.12500 34479.18750 0.667 3 0 2026 05 26 06.0 07.50 34479.25000 34479.31250 1.000 4 0 2026 05 26 09.0 10.50 34479.37500 34479.43750 1.000 4 0 2026 05 26 12.0 13.50 34479.50000 34479.56250 0.333 2 0 2026 05 26 15.0 16.50 34479.62500 34479.68750 1.333 5 0 2026 05 26 18.0 19.50 34479.75000 34479.81250 2.333 9 0 2026 05 26 21.0 22.50 34479.87500 34479.93750 3.667 22 0 2026 05 27 00.0 01.50 34480.00000 34480.06250 1.667 6 0 2026 05 27 03.0 04.50 34480.12500 34480.18750 2.333 9 0 2026 05 27 06.0 07.50 34480.25000 34480.31250 2.667 12 0 2026 05 27 09.0 10.50 34480.37500 34480.43750 1.333 5 0 2026 05 27 12.0 13.50 34480.50000 34480.56250 1.667 6 0 2026 05 27 15.0 16.50 34480.62500 34480.68750 2.667 12 0 2026 05 27 18.0 19.50 34480.75000 34480.81250 -1.000 -1 0 2026 05 27 21.0 22.50 34480.87500 34480.93750 -1.000 -1 0