SUB-SOLAR AREAS DURING SOLAR FLARES SEISMICALLY ACTIVE

SUMMARY

There were a series of solar flares in the moderate M-class range today. These tended to concentrate while Africa and Europe were sub-solar (near local noon). Areas which are sub-solar are expected to experience strongest triggering effects from SFE (Solar Flare effects) because the solar wind and geomagnetic radiation hit these areas head on.
The first flare (M4.6) maximized at 02:51UT. This was followed at 03:17UT by a moderate earthquake in the Queen Charlotte Island/No. Vancouver Island region. The second flare maximized at 06:12 UT and was responsible for a brief proton
Storm at the same time. This storm may have reduced global seismicity temporarily, as previous observation tends to support.
The third flare, and the largest in more than two weeks began around 09:46-09:59 UT. At the time the longitude of 32E was exactly sub-solar - that is, it was local noon when this flare occurred. Several hours later the strongest earthquake of the day (a Mb 5.5) struck in the Lake Tanganyika region of Africa. This unusual earthquake had it's epicenter at 7.7S 31.9E where it had been exactly positioned at local noon when the flare struck earlier.
The fourth flare occurred at 11:28 and maximized at 11:39 UT. Local noon
At the time of this flare was occurring in central Europe and southward to the Indian-Atlantic ridge south of Africa. As the flare effects struck the ionosphere, a Mb 4.8 earthquake occurred in Poland (at 16.2E longitude) where it was very nearly subsolar at the time. Several hours later a series of four (possibly more) earthquakes were recorded at 15.7E and 52S on the Atlantic-
Indian Ridge south of Africa, another area where SFE would have been expected to be maximized. These events were in the Mb 5.0 range.
All of the events associated with today's flares were unusual and well positioned to suggest SFE triggering of these seismic phenomena.

GLOBAL

Two earthquakes occurred in the world today (per NEIC) which were not associated with the solar activity - a Mb 5.3 in West Irian and a Mb 4.8 in the Carlsberg Ridge area of the northern Indian Ocean south of India. A list of other, lesser magnitude earthquakes accompanies this report.

U.S./CANADA

Seismicity in the western U.S. was moderate today. There were 5
Earthquakes of Ml 2.0 or greater in Central California - mostly
In the Yountville and Pinnacles regions; and several in the Simi Valley,
Area of southern California; an area which as shown considerable
Activity in recent months, often simultaneous with strong geomagnetic/
Solar events. Nine events of Ml>=2 have been recorded thus far in
Nevada/California area during the previous day.

The largest earthquake in the U.S./Canada region today occurred as a Ml 4.5 event in the northern Vancouver Island region. This event occurred about 15 minutes after the first strong solar flare (the strongest flare in more than two weeks). Vancouver is an area where strong events often occur in concert with solar events as well.

NEW ZEALAND

Moderately strong activity continued to be recorded on the IGNS
Web seismogram. A portion of this is occurring in the White Island
Region off North Island. The current eruption of this volcano is visible
From land with remote camera. See:

http://www.gns.cri.nz/geonet/volcanocam.htm

and click on the "White Island from Whakatane" image you should be able to see
that the lack of wind out there makes the steam plume visible from the land.

The IGNS on-line Seismometer can be found at:
http://www.gns.cri.nz/news/earthquakes/latest_drum.html

GEOMAGNETIC/SOLAR FIELDS

A series of moderate M-class solar flares erupted today on the sun.
These occurred from early morning until mid-day (UT). After the flares
began a proton storm started shortly after 06:00 UT. The combination of
these events apparently had significant effect on seismicity in the region
which was sub-solar at the time - Africa, Europe and South of Africa,
where a series of strong earthquakes accompanied the flares.
The most likely immediate triggering occurred with Flare # 6790
Which coincided with a moderately large, unusual earthquake of Mb 4.8
In Poland both of which started within a minute of 11:28 UT. At the time
Poland was directly sub-solar and subject to maximum triggering potential
From ionospheric effects.
The proton storm accompanied the largest flare (#6690) at about 06:12 UT.

Flare # START MAX END CLASS
6640 + 0244 0251 0256 M4.6
6690 + 0552 0612 0616 M5.1
6760 + 0946 0959 1004 M4.3
6790 + 1129 1139 1147 M4.5
6840 + 1703 1711 1718 M3.5
6850 + 2100 2107 M2.4

For general space weather conditions see:
http://sec.noaa.gov/today.html
For Solar flare data see:
http://sec.noaa.gov/ftpdir/indices/events/20020220events.txt