Tropical Storm Fred degraded to a tropical depression and then to a mere tropical wave, but given the warmth of the Gulf waters it will soon be crossing over, Fred is expected to reform and become a tropical storm again. The good news is that the latest projections show it tracking further west than previously thought, so it looks now like it will pass over the length of the State of Alabama and miss Atlanta, other than some outer bands of rainfall. Bad news for Mobile and Alabama, but good news for Georgia.
But what's this? Right behind Freddy we have Grace. Just a tropical storm now, but it's got lots of warm open water to pass over which it can use to build up strength. It's currently projected to pass over Haiti (as if that country hasn't suffered enough with this morning's 7.2-magnitude earthquake) and then beeline toward Miami. After that, it's anyone's guess where it's going, but like Fat Freddy, I hope it stays away from Atlanta.
The IPCC Sixth Assessment Report projects a greater number of the most intense hurricanes, with slower translation speeds (the speed of hurricane movement along the storm track) and higher rainfall potential for the East Coast, the Gulf Coast, and Mexico’s Pacific Coast. However, the number of all hurricanes, not just the most intense, is more difficult to predict, due to the many factors involved in hurricane formation and track forecasting.
At the location of this morning's 7.2-mag earthquake in Haiti, the Caribbean tectonic plate is moving eastward relative to the North American plate. At the location of the earthquake, motion between the Caribbean and North America plates occurs along two major east-west-trending fault systems—the Septentrional fault zone in northern Haiti and the Enriquillo-Plantain Garden fault zone to the south. The Gonâve microplate occurs between the two zones. Today's earthquake likely occurred on a north-dipping fault plane within the Enriquillo-Plantain Garden fault zone.
About 31 minutes before this morning's earthquake in Haiti, a 6.9-mag earthquake occurred off of the Alaskan Peninsula. Despite the coincidence in the timing of these two earthquakes, the large distance between the two events makes any relationship unlikely.
On January 12, 2010, a 7.0-mag earthquake occurred approximately 45 miles east of the today's earthquake. The 2010 earthquake caused substantial damage in the city of Port-au-Prince and surrounding regions, where damage from the earthquake and subsequent landslides caused over 200,000 fatalities. Although today's earthquake likely occurred within the same fault zone as the January 2010 earthquake, the 2010 earthquake occurred on an adjacent thrust fault and not directly on the main plate-boundary fault.
In addition to the 2010 earthquake, the Enriquillo-Plantain Garden fault zone also caused large earthquakes in 1860, 1770, and 1751.
There were two major earthquakes in 1751 alone. On October 18, a major earthquake caused heavy destruction in the Gulf of Azua (the eastern end of the Enriquillo fault); that earthquake also generated a tsunami. Then, on November 21, a second major earthquake destroyed Port-au-Prince.
On June 3, 1770, a major earthquake centered west of the city destroyed Port-au-Prince again. As a result of the 1751 and 1770 earthquakes, and minor earthquakes that occurred between them, local authorities required building with wood and forbade building with masonry.
On April 8, 1860, a major earthquake occurred farther west of the 2010 earthquake and was accompanied by a tsunami.
Impermanence is swift. All conditions are marked by change, and life-and-death is the great matter.
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