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December 2008 NMDB Kiel midterm Meeting 1
Checking the simultaneous profiles on 1min data from Lomnický štít during strong CR variations
R. Langer, K. Kudela
December 2008 NMDB Kiel midterm Meeting 2
GLE list registered at Lomnicky stit NM station
List of GLEs detected by our GLE filter code
GLE / GLE onset / GLE max 60 / 1345-1350 / 1420-1425
65 / 1113-1114 / 1118-1119
69 / 0650-0655 / 0705-0710
70 / 0250-0251 / 0300-0301
December 2008 NMDB Kiel midterm Meeting 9
Method – checking algorithm
If next value is bigger than average+standard deviation of previous 10 values we check next three values to same condition, if all four values (T1 .. T4) are fulfill condition, we find GLE
December 2008 NMDB Kiel midterm Meeting 10
Table 1. a) of detected increases
Method based on 10 points prehistory
Checking algorithm condition valid in 5 or more chanels (for condition T1)
For nex two point we check if condition was valid in 6 or more chanels (for T2 > T1, T3 > T1)
GLE 065 was not detected by the checking algorithm
Mistake events are quite rare
December 2008 NMDB Kiel midterm Meeting 11
Table 1. b) of detected increases
Same method as in evaluation Table 1. a)
From the measured data not corrected to the barometric pressure
We think that barometric pressure corected data will give more mistake events (because errors in pressure measurements) during checking procedure, but result was opposite. We find more mistakes events in not corrected data (see line with DOY 341, YY 05 in table right here) .
Because that we are checking just corrected data.
December 2008 NMDB Kiel midterm Meeting 12
Table 2. of detected increases
Method based on 6 points prehistory
Checking algorithm condition valid in 5 or more chanels (for condition T1)
For nex three points we check if condition was valid in 5 or more chanels (for T2 > T1, T3 > T1, T4 > T1)
GLE 070 was not detected by the checking algorithm
Mistake events are quite often
December 2008 NMDB Kiel midterm Meeting 13
Table 3. of detected increases
Method based on 15 points prehistory
Checking algorithm condition valid in 5 or more chanels (for condition T1)
For nex three points we check if condition was valid in 5 or more chanels (for T2 > T1, T3 > T1, T4 > T1)
GLE 070 was not detected by the checking algorithm
Mistake events are quite rare
December 2008 NMDB Kiel midterm Meeting 14
Table 4. of detected increases
Method based on 10 points prehistory
Checking algorithm condition valid in 5 or more chanels (for condition T1)
For next four points we check if condition was valid in 5 or more chanels (for T2 > T1, T3 > T1, T4 > T1, T5 > T1)
GLE 060 and GLE 070 were not detected by the checking algorithm
Mistake events are very rare.
December 2008 NMDB Kiel midterm Meeting 15
Table 5. of detected increases
Method based on 10 points prehistory
Checking algorithm condition valid in 5 or more chanels (for condition T1)
For next four points we check if condition was valid in 5 or more chanels (for T2 > T1, T3 > T1, T4 > T1)
All expected GLE were detected by this checking algorithm
This algorithm we recoment to use in the future.
December 2008 NMDB Kiel midterm Meeting 16
Table 6. of detected increases in year 2001
Same algorith like showed for Table 5.
But for next four points we check if condition was valid in 5 or more chanels (for T2 > T1, T3 > T2, T4 > T3)
This was just test to improve checking method
GLE 060 was not detected by this checking algorithm
December 2008 NMDB Kiel midterm Meeting 17
Table 7. of detected increases
Same algorith like showed for Table 5.
In this case condition was T1 > average + (1.1 * standard deviation) of previous 10 values
This was just test to improve checking method
GLE 070 was not detected by this checking algorithm
December 2008 NMDB Kiel midterm Meeting 18
Table 8. of detected increases
Same algorith like showed for Table 5.
Corrected sums was taken like chanels in previous cases
Condition was stricter: for T1, T2, T3 and T4 was valid for both „chanels“ simultaneously, (for T2 > T1, T3 > T2, T4 > T3)
GLE 065 was not detected
Mistake events dont appear
December 2008 NMDB Kiel midterm Meeting 19
Table 9. of detected increases
Same algorith like showed for Table 5.
Corrected sums was taken like chanels in previous cases
Condition for T1, T2, T3 and T4 was valid for all three „chanels“ simultaneously (for T2 > T1, T3 > T2, T4 > T3)
This algorithm can be used for real time detection of GLE.
Result for calculation with three station taken like chanels are equivalent to results in Table 8.
December 2008 NMDB Kiel midterm Meeting 20
Ground level enhancement real-time alarm based on 8 high latitude NMs including those at high mountain is described by (Kuwabara et al, SW 2006a). Three level alarm system (by number of NMs exceeding threshold value above that of baseline) is suggested. Out of 10 GLEs in 2001-2005 archived data the system produced 9 correct alarms. GLE system gives earlier warning than satellite (SEC/NOAA) alert.
Number of minutes by which GLE alert precedes earliest SEC proton alert.