Matt SienkiewiczDepartment of Marine and Environmental Systems

Marine forecasts Conduct SAR operations Atmosphere-Ocean coupled hurricane

prediction models Forecast oil slick movement

Oil

MODIS 19 JULY 2010

A warm water current that sheds anticyclonic eddies once or twice a year.

Implemented in 2005 One-day nowcast and 6-day forecast (144

hours) Curvilinear coordinate system Based on Hybrid Coordinate Ocean Model

(HYCOM) Covers entire Atlantic basin

(Mehra and Rivin, 2009)

GoM: 4-5 km

Sea surface height – satellite altimetry data Sea surface temperature – AVHRR Diurnal and Semi-diurnal tides River outflow and freshwater flux – USGS In situ measurements

◦ CTD casts◦ Argo floats

Two drifters deployed in eastern edge of Loop Current

Drifters report lat/lon every hour

87803

87806

Exit Loop Current

Four separate trajectories initialized at actual drifter location at:◦ Deployment◦ 14 Jun 00Z◦ 18 Jun 00Z◦ 21 Jun 00Z

Trajectories run out to 144th forecast hour, except on 14 Jun (96th hour)

87803

87803

16 JUN 2010

18 JU

N 2

010

24 JUN 201027 JU

N 2

010

87803

87806

87806

87806

16 JUN 2010

18 JUN

2010

24 JUN 2010

24 JUN

2010

R2 = 0.9846

3

4

21

0

0 32

1

4

50km

Mean distance from center point.

•Looking for areas in RTOFS most sensitive to error•Analysis run for entire Gulf of Mexico•Initial time 00Z on 10 Jun 2010•Run for 120 hours of forecasts

Beginning 10 JUN 2010 00Z

Max mean spread: 275.1 km

Large errors between drifters and RTOFS for Loop Current

Initial RTOFS placement of drifters outside of Loop Current

Outside edges of current in RTOFS seem more subjected to shear/eddies

Overall RTOFS made a poor display for this analysis in the Loop Current

Next Speaker: Cory Hodes