WEATHER PHENOMENA

 

Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of  the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models.  Currently the following tropical storms appear to have potential to affect seismicity in the coming week:

 

 

TROPICAL CYCLONE OMA (15P)

 

----  -------  ----------  --------  -----  ------  -------  ---------------

TC    OMA      2019-02-15  00:00 UT  15.5S  165.2E  070 kts  Vanuatu Islands       

 

TC Oma (15P) continued today in the region of northern Vanuatu with winds up to 70 kts. It is expected to track to the southwest over the next several days. Seismic enhancement in the region of Vanuatu could accompany the passage of this storm through the area. A moderate to large earthquake in the Loyalty Islands is possible as Oma passes over that region  around February 16-18.

 

 

TROPICAL CYCLONE GELENA (13S)         

 

----  -------  ----------  --------  -----  ------  -------  ---------------

TC    GELENA   2019-02-15  00:00 UT  28.2S   85.8E   050kts  East of Madagascar            

 

TC Gelena (13S) continued today east of Madagascar with winds up to 055 kts. It is expected to track to the southeast over the next week. The antipodal region at 28N  95W is antipodal to the northern Mexico and southern Texas/Oklahoma.  Antipodal triggering may occur in these regions may occur.

 

TIDAL EFFECTS ON SEISMICITY

 

 

February 15, 2019 is the eleventh day after the beginning of the new lunar month. Regions most likely to experience tidal triggering  on this day (With associated magnitude ranges; the percent change in seismicity rate over background seismicity rate on this day of the lunar month; statistical z-value and significance level) are:

 

Region Magnitude range %change z-value Significance level

 

So. Alaska MB>=3.0 9 2.7 0.02

Australia MB>=4.0 33 2.6 0.03

New Madrid MB>=0.0 34 3.4 0.01

So Indonesia MB>=4.0 42 3.1 0.01

 

Regions expected to experience reverse triggering (i.e. they are unlikely to experience a significant event at this period of the lunar cycle) are:

 

 

Region Magnitude range %change z-value Significance level

 

Geysers MB>=0.0 -6 -2.2 0.05

NE Europe MB>=4.0 -10 -2.3 0.04

Tonga MB>=4.0 -29 -2.0 0.05