Hurricanes are among the costliest and deadliest natural disasters in the world. Understanding how both hurricane frequencies and intensities vary from year to year as well as how this is manifested in changes in damages that occur is a topic of great interest to meteorologists, public and private decision makers and the general public alike.

Previous research into long-term trends in hurricane-caused damage alongthe United States coast has suggested that damage has been quickly increasing within the last two decades, even after considering inflation. However, to best capture the year to year variability in tropical cyclone damage, consideration must also be given toward two additional factors: coastal population changes and changes in wealth. Both population and wealth have increased dramatically over the last several decades and act to enhance the recent hurricane damages preferentially over those occurring previously. More appropriate trends in the United States hurricane damages are calculated when a normalization of the damages are done to take into account inflation, and changes in coastal population and wealth. Such normalization provides quite a different picture both in the total damage produced and the decade to decade changes of such damage. Similar work is progressing on normalized hurricane damages in Cuba and other countries.

Accurate records of Atlantic and U.S. landfalling hurricanes extend backto the mid-1940s and the turn of the century because of aircraft reconnaissance and instrumented weather stations along the U.S. coasts, respectively. Such long-term records are not exceeded elsewhere in the tropics. The Atlantic hurricane, U.S. landfalling hurricane and U.S. normalized coastal damage time series are examined for interannual trends and multidecadal variability. Various environmental factors including Caribbean sea level pressures and 200mb zonal winds, the stratospheric Quasi-Biennial Oscillation, the El Niño-Southern Oscillation, African West Sahel rainfall and Atlantic sea surface temperatures, are analyzed for interannual links to the Atlantic hurricane activity. All show significant, concurrent relationships to the frequency, intensity and duration of Atlantic hurricanes. Additionally, variations in the El Niño-Southern Oscillation and African West Sahel rainfall are significantly linked to changes in U.S. tropical cyclone-caused damages. Finally, it is observed that much of the multidecadal hurricane activity can be linked to the Atlantic Multidecadal Mode - an empirical orthogonal function pattern derived from a global sea surface temperature record. Such linkages may allow for prediction of Atlantic hurricane activity on a multidecadal basis.

As part of the National Oceanographic Partnership Program Year of the Ocean (YOTO) contribution, a total of 32 WOCE surface drifters have to date been launched in the southwestern Caribbean Sea using vessels of the Colombian Navy. These deployments consist of groups of eight surface drifters launched nominally every three-four months on a line between Cartagena and San Andres Island. All drifters gave been drogued at a depth of 15 m and are designed to report surface positions and temperatures. This launch program is planned to continue through at least the next year with launches of six floats roughly every three months. These drifter tracks can be found at Web pages for the NOPP drifters (www.drifters.doe.gov), the IAS oceanography page (IASlinks.org) or the Intra-Americas Sea Initiative page (www.rsmas.miami.edu/groups/IASI/IASIhome.htm).

The purpose of these deployments is to explore the structure and variability of a prominent circulation feature in the southwestern Caribbean known as the Panama-Colombia Gyre (PCG). This cyclonic gyre has been revealed by the drifter tracks obtained so far to be a permanent feature of the circulation but one that shows considerable seasonal and shorter-term variability as well. Retention times for drifters launched in the PCG are order several months. As can be seen from a companion presentation (Wilson and Leaman) very few drifters from the open Caribbean find their way into the PCG; however, a large number of PCG drifters exit the PCG at various locations and times, and a significant number of these become trapped in shelf waters south of Cuba. This latter fact has implications for biological problems of larval transport and interconnectivity of coastal habitats.

Observed drifter tracks are compared to numerical surface drifters "deployed" in a high-resolution isopycnic-coordinate numerical model (MICOM model, E. Chassignet, RSMAS). Similar seasonal variability is observed in both real and numerical drifter trajectories; in particular, a deformation of the flow field in late summer has beenobserved in the model as well as in two sequential years of drifter observations. Over longer periods, numerical drifter concentrations in the PCG decrease until a balance is achieved between northward Ekman advection and diffusion of drifters from the interior.

South Florida coastal ecosystems consist of a collection of distinct marine environments that are strongly connected by their circulation and exchange processes on a regional scale, and by oceanic boundary currents to remote upstream regions of the Gulf of Mexico and Caribbean. Circulation and exchange of coastal waters depend on the interplay of local responses to different forcing in different subregions. We present new observations to describe the circulation and exchange processes characteristic to each subregion and their effect on transport trajectories that provide the regional linkages for the spread of waterborne materials, as well as recruitment pathways from offshore spawns to nearshore nurseries. The combined local responses to the different forcing tends to form a recirculating current system that strongly connects the entire south Florida coastal region. The recirculation system is supported by wind forced currents on the southwest Florida shelf, western Florida Bay and Keys coastal zone, combined with a mean slope driven current toward the southeast that couples the Gulf and Atlantic coastal waters, as well as offshore boundary currents and eddies that intensify countercurrents along the Keys. The south Florida recirculation system forms a larval retention zone and recruitment pathway for pelagic larvae spawned in the Florida Keys coastal waters or foreign imports transported from remote sources.