# DOI: https://doi.org/10.5880/Kp.0001 # LICENCE: CC BY 4.0, please cite: # 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 # 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 # The Kp index was introduced by Bartels (1949) and is produced by Geomagnetic # Observatory Niemegk, GFZ German Research Centre for Geosciences. Quietest Days Most Disturbed Days Month Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 D1 D2 D3 D4 D5 Jan 1990 27 19 7K 28A 6A 14A 18A 17A 15A 13A 24 29 30 23 22* Feb 1990 12K 9A 8A 10A 13A 3A 6A 11A 21A 26A 16 20 23 17 19 Mar 1990 17 4 16A 10A 31A 7A 9A 3A 8A 5A 21 30 26 25 12 Apr 1990 1 8 6A 7A 19A 5A 4A 16A 2A 21A 10 12 11 14 17 May 1990 16 14 17 6 15 12A 7A 28A 24A 1A 26 27 10 22 18 Jun 1990 20 17 30 16 5 21 4 22 2 3 12 14 13 9 7 Jul 1990 25 24 23 9 1 17 22 7K 31K 2 28 29 20* 19* 10* Aug 1990 5 9 8 10 28 25 4K 12A 7A 11A 23 26 22 21 30 Sep 1990 2 3 30 29A 27A 4A 8A 28A 9A 10A 11 16 15 1 22 Oct 1990 1 8 28 18 2 17K 27A 7A 25A 23A 10 11 12 15 31 Nov 1990 6 5 14 4 24 13 15 22 23 25 27 16* 28* 17* 18* Dec 1990 10 19 11 26 22 29 21 28 7 2 4* 24* 13* 5* 30* Jan 1991 7 6 14 19 22 30 29 21 20 28 24 12* 31* 25* 15* Feb 1991 18 17 16 3 6 4K 24 20 19A 26A 1 23 28* 9* 11* Mar 1991 29 11 15 3 14A 16A 18A 4A 31A 2A 24 25 26 27 30 Apr 1991 20 11 13 16 8 15 14 21 10A 23A 29 4 3 30 28 May 1991 11 18 20 12 19 6 5 7 21A 15A 31 2 25 14 17 Jun 1991 16 29 14A 28A 27A 15A 20A 3A 22A 30A 5 13 10 11 1 Jul 1991 5 26 31 28K 29 24 7A 27A 6A 30A 13 9 14 8 17 Aug 1991 10A 13A 26A 25A 24A 8A 23A 29A 9A 7A 19 20 12 2 31 Sep 1991 23 21 17 18K 24A 16A 22A 20A 12A 15A 25 1 9 27 28 Oct 1991 16 15 12 17K 13A 14A 18A 19A 11A 9A 29 28 31 2 1 Nov 1991 27A 26A 28A 25A 12A 7A 13A 30A 24A 29A 9 1 8 21 19 Dec 1991 6 7 22K 15A 25A 8A 26A 5A 31A 9A 17 27 29 21 28 Jan 1992 24 23 25 19 9A 18A 26A 21A 7A 22A 13 11 16 12 30 Feb 1992 16 15 5A 11A 6A 28A 14A 13A 12A 19A 3 9 20 21 27 Mar 1992 19 14 20 13K 6A 15A 28A 7A 3A 27A 23 9 17 24 21 Apr 1992 11 12 17 16 10 27 9 14 2K 13 3 6 8 7* 20* May 1992 17 16 14 15 6 5 26A 31A 21A 20A 10 11 22 9 8 Jun 1992 4 16 6 2 17 3K 5 14 20A 1A 8 29 12 30 11 Jul 1992 11 7 26 19 9 29 4 18 8 6 22 13 1* 28* 23* Aug 1992 3 17 31 2 25 28 30K 18 12 10A 23 22 5 20 7 Sep 1992 1 27 24 13 12 21A 14A 26A 20A 23A 17 10 9 29 3 Oct 1992 24 23 5 3 21 25A 4A 8A 7A 22A 12 15 27 1 29 Nov 1992 20 29 27 28 18A 19A 21A 17A 26A 16A 9 23 4 2 15* Dec 1992 26 25 6K 16K 5A 22A 12A 27A 23A 13A 29 28 8 17 9* Jan 1993 23 29 22A 28A 21A 24A 1A 27A 16A 18A 31 3 4 2 10 Feb 1993 15 26 27K 6 16 5 25 14K 24 19A 8 1 17 22 9 Mar 1993 5A 26A 6A 31A 19A 27A 23A 25A 10A 29A 9 24 11 15 16 Apr 1993 27 3 2 28 26 11A 1A 19A 24A 25A 5 4 21 13 15 May 1993 25 23 21 24 22 26 30 11 4 31 9 10 8 28 17* Jun 1993 21 16 18 28 1 17 20 19 22 15 4 5 24 7 10 Jul 1993 14 17 16 26 24 18 6 5 25 15 2 3 1 11 29* Aug 1993 14 1 2 23 25 11 30 13 21 24 16 27 4 17 18* Sep 1993 1 18 10 19 17 9 2 16 22 11 13 3 14 4 29 Oct 1993 15 7 30 20 16 3 5 21 4K 2A 9 27 25 10 11 Nov 1993 12 30 2 28 24 22 11K 17K 25 27A 4 5 19 18 6 Dec 1993 9 29 28 13 14 30 12 6 27A 11A 2 8 3 1 16 Jan 1994 10 9 24 5 7 25 4K 8 23A 21A 12 17 13 14 1 Feb 1994 24 1 18A 26A 27A 28A 17A 3A 23A 2A 21 8 6 7 22 Mar 1994 4 29 31 26A 5A 27A 6A 1A 28A 20A 9 7 8 10 15 Apr 1994 30 28 27 26 29 1 22A 24A 20A 25A 3 17 4 9 2 May 1994 27 21 20 22 13A 23A 26A 19A 12A 17A 2 30 3 5 29 Jun 1994 23 24 25 16 15 22 17A 9A 8A 21A 29 26 2 12 3 Jul 1994 12 10 13 26 8 11 20 5 22 9K 16 14 2 1 15 Aug 1994 8 4 2 30 7 6 3 9 5 29 13 14 12* 15* 11* Sep 1994 30 4 23 2K 20 22K 3 18 19K 24K 7 9 8 26 27* Oct 1994 21 1 27 28 17 18 16 19A 26A 20A 3 30 23 29 7 Nov 1994 25 23 24 12 8 16 22 18 13 17K 6 26 27 20 4 Dec 1994 31 22 21 4K 18 19K 30A 5A 14A 17A 24 6 2 15 25* Jan 1995 28 26 15 27 24 14 1 19 25 12 30 17 3 18 29 Feb 1995 25 22 24 10 9 23 21 5 20 17 13 28 12 14 11 Mar 1995 21 22 7 8 19 18 20 6K 24 25 12 13 1 26 11 Apr 1995 3 21 4 15 16 30 14 17K 6K 19 7 8 27 9 10 May 1995 1 21 15 10 27 14 22 11 28 29A 3 2 5 16 30 Jun 1995 13 12 8 24 9 17 11 15 14 27 19 30 1 3 20 Jul 1995 10 11 6 5 12 7 21 8 13 2 16 24 17 1* 18* Aug 1995 31 21 6 1 30 28 4 20 2 5 14 8 9 25* 10* Sep 1995 29 18 22 1 2 19 3 26 30 25 8 27 5 11 6 Oct 1995 28 29 1 26 25 15 27 14 16A 17A 4 20 8 7 18 Nov 1995 24 25 21 9 15 26 14 16K 13 23 1 6 27 2 5* Dec 1995 8 13 30 18 29 7 11 28 20 6 24 22 16 1* 4* Jan 1996 9 8 10 11 7 23 4 1 25 6K 13 14 29* 15* 20* Feb 1996 6 3 21 4 5K 1A 7A 19A 9A 8A 11 24 25* 26* 23* Mar 1996 7 2 6 1 30 31 15 29 5 3 21 11 20 13 24 Apr 1996 7 6 26 28 29 2 25 30 8K 24 17 14 19 12 18 May 1996 18 28 7 23 6 12 11 9 10 2 13* 14* 20* 4* 16* Jun 1996 13 14 25 22 1 3 9 12 26 2 6* 19* 29* 17* 18* Jul 1996 10 9 27 11 24 29 19 6 23 16 31* 8* 28* 3* 5* Aug 1996 8 10 19 12 11 18 22 21 7 4 29 25* 30* 27* 28* Sep 1996 3 30 2 6 1 5 8K 29A 7A 9A 20 10 21 26 12 Oct 1996 6 5 7 26 27 15 1 17K 4 25K 19 22 23 18 9 Nov 1996 30 2 3 1 23 8 11 7 16 22 14 13* 15* 18* 17* Dec 1996 19 6 20 5 1 8 28 26 27 24 10 11* 15* 16* 4* Jan 1997 16 6 17 4 3 5 23 24 15 14 10 28 26* 11* 27* Feb 1997 19 20 4 13 7 15 1 14 25K 5K 28 27 10 11 9 Mar 1997 9 10 20 19 23 4 11 21 31 14 29 28 26* 1* 12* Apr 1997 28 15 26 27 29 20 8 14 9 25 11 17 21 22* 18* May 1997 12 13 23 29 19 22 9 7 21 8 15 1 27 2* 16* Jun 1997 21 14 13 18 5 11 24 17 20 30 9 27* 8* 7* 3* Jul 1997 14 12 13 29 1 8 26 5 11 6 31* 7* 15* 24* 9* Aug 1997 26 6 5 19 23 27 31 25 2 8 3 28* 14* 29* 13* Sep 1997 25 19 7 26 2 1 24 23 5 20 3 10* 18 9* 4* Oct 1997 5 19 15 21 16 6 14 18 4 22 1 10 25 24 27* Nov 1997 29 27 28 21 2 20 25 12 26 19 23 22 7 6* 14* Dec 1997 27 8 28 13 9 25 26 22 14 29 30 10* 11* 18* 5* Jan 1998 15 28 26 4 23 14 3 5 19 13 7 30* 6* 20* 31* Feb 1998 26 6 16 7 24 2 25 5 3 15 18 11* 17* 28* 9* Mar 1998 8 9 19 7 18 3K 23K 24A 6A 17A 10 21 11 29 15 Apr 1998 1 5 15 2 29 6 13 19 3 18K 24 26 25 10* 17* May 1998 14 31 13 28K 6 19 27 15A 22A 26A 4 3 2 5 29 Jun 1998 17 28 30 29 1 27 13 18K 11K 12 26 24* 7* 6* 10* Jul 1998 14 8 27 20 15 19 26 13 10 7 23 16 31 24 6* Aug 1998 17 9 16 18 15 3 21K 13 2 5 27 6 26 7 28 Sep 1998 14 16 28 4 20 5 15 6 10K 7K 25 24 18 1* 26* Oct 1998 16 5 14 4 6 26 15 13 12K 31K 19 2 7 1 21 Nov 1998 11 12 1 2 4 17K 22 21 3 10K 9 8 13 14 7 Dec 1998 17 18 27 13 21 31 24 8 2 22 11 29 26* 5* 25* Jan 1999 31 19 30 3 26 12 18K 11 17 21K 13 14 23 15 8* Feb 1999 1 2 26 9 20 16 27 21 3 10 18 19 12 11 17* Mar 1999 22 16 24 27 20 21 17 23 28 26 1 4 10 29 7 Apr 1999 15 13 22 23 25 24 9 26 18 14A 17 20 29 30 28* May 1999 11 17 31 22 16 29 4 8 9 10 18 13 1 25* 2* Jun 1999 21 14 22 20 30 6 25 19 5 11 27 28 26* 9* 8* Jul 1999 4 17 5 19 16 18 9 10 13 11 30 2 31 22 21* Aug 1999 14 3 21 10 2 11 5A 8A 12A 1A 20 23 24 17 18 Sep 1999 25 24 6 5K 8A 20A 9A 2A 11A 19A 13 22 27 16 12 Oct 1999 20 7 6 19K 30 18 9K 8A 3A 1A 22 12 10 23 14 Nov 1999 27 26 29 15 4 5K 3K 2A 28A 20A 13 7 8 9 11 Dec 1999 22 21 26 14 23 20 19 15K 2 1 31 4 13 5 6*