Will hurricanes spread Gulf oil inland?

With the 2010 hurricane season just around the corner (June1-Nov 30th) there has been considerable speculation as to what will happen if/when a hurricane strikes the oil slick area in the Gulf of Mexico.

NASA MODIS satellite image shows growing oil slick off the Mississippi Delta on May 11th.

(click for bigger image)

This year there may be increased reason for concern. Hurricane forecasters expect an above average number of Atlantic hurricanes this year. And already tropical Atlantic SST's are running as much as 2 degrees C above average in the main development area (MDA) for Atlantic Hurricanes off the African coast.

The record warm water temperatures support the notion of increased Atlantic hurricane activity this year.

Tropcal Atlantic SST anomalies shows record warm water in the eastern Atlantic.

Here's what meteorologists know and don't know about hurricanes interacting with the Gulf of Mexico oil spill.

What we think we know:

Hurricane development & intensity

-According to Dennis Feltgen from the National Hurricane Center, the oil slick wouldn't affect a hurricane's intensity or track. The circulations are too big and too well established, and hurricanes are driven by steering currents far above the ocean's surface.

-Oil on the ocean's surface DOES suppress evaporation of sea water. That could act to suppress tropical storm development as evaporation is a primary driver of tropical cyclone development.

Oil spill containment:

-High winds and rough seas would likely stop containment efforts destroy containment booms, opening shores to oil.

-Storm surges would likely carry increased volumes of oil to inland bays and beaches.

What we don't know:

-There is the possibility that hurricane force winds could lift oil off the sea surface and send it airborne in a blowing oily sea spray. If the oil and dispersant is aerosolized, it could be carried far inland and become a threat to crops and human health. We don't know what kind of wind speeds it would take to do this, and how far the toxic oily spray could travel. This is likely a worst case scenario.

-Will the Gulf Loop Current tap into the oil slick and drive it around Florida and toward the east coast? This may increase the likelihood of a hurricane impact over an oil slicked area.

Gulf of Mexico "Loop Current" may push oil eastward over time.

Bottom line: A hurricane over a major oil spill has never happened before in human history. We are literally in uncharted waters here. This is like a big lab experiment that may take place over the next 6 months. We just don't know how an oil slick this size and hurricanes will interact.

We may find out in the coming months.

PH