Marine scientists and climate experts have sounded an alarm ahead of this year’s hurricane season: the Gulf of Mexico Loop Current, an area of warm water that begins its journey in the Caribbean, is looking a lot like the 2005 model. As such, they’re forecasting another devastating parade of intense storms.
Joseph Kuehl, associate professor of mechanical engineering at the University of Delaware, said that while he can’t say for certain what the Loop Current will do in the next year or so, the present trends for both the near- and long-term suggest an increased potential for development of intense hurricanes.
“There are reports that, climatologically, the Gulf Stream – the western boundary current along the U.S. East Coast – is weakening,” Kuehl said. “This suggests that in the years to come, ‘loop’ states will be more present and correspondingly there would be an increased potential for the development of intense hurricanes.”
Forecasting anything concerning ocean circulation is a challenge. But predicting the movement of the Gulf of Mexico Loop Current is a much larger challenge in oceanography – and a potentially dangerous one considering its impact on the annual hurricane season, Kuehl said.
Here’s why:
- The numbers can’t always be trusted. Observational data from the real ocean must be fed into models so that the initial condition (what the circulation is right now) is correct. The problem is, getting accurate, timely data from the ocean is difficult and expensive. The ocean is a very corrosive environment, and specialized equipment is required just to survive deployment. Communication options from the ocean (surface or depths) back to shore are limited by logistics and power constraints.
- The ocean is really big. Measuring the flow or stratification in one place is not enough to initialize a model. Many measurements of many different quantities are required at many different locations.
- The Loop is dynamic. In particular, the Loop Current tends to assume one of several states and transitions between these states are abrupt and extremely sensitive to various parameters of the system (ocean topography, dissipation, Caribbean inflow, wind forcing, etc.).
- There’s little margin for error. Even if you have all the parameters of the system correct, you still cannot tell which state the system should be in, unless you know the history of the system. Basically, what this all amounts to is that above and beyond traditional ocean forecasting, a numerical model of the Gulf of Mexico Loop Current must be very meticulously constructed. At the present time, it is unclear if the inherent errors and approximations made when developing ocean forecasting models are small enough to accurately predict the Gulf of Mexico Loop Current.
