NOAA/NOS/OCS/Coast Survey Development Laboratory

Initialization Fields and Model Forcings for CBOFS2

Lyon Lanerolle1,2, Richard Patchen1 and Frank Aikman III1

1National Oceanic and Atmospheric Administration (NOAA)National Ocean Service/Office of Coast Survey/Coast Survey Development Laboratory

1315 East-West Highway, Silver Spring, MD 20910

2Earth Resources Technology (ERT) Inc.10810 Guilford Road, Suite 105, Annapolis Junction, MD 20701

NOAA/NOS/OCS/Coast Survey Development Laboratory

CBOFS2 Model Grid

NOAA/NOS/OCS/Coast Survey Development Laboratory

CBOFS2 Wind Speed Time-SeriesCriteria for Choosing Hindcast Period

Hurricane Isabel

NOAA/NOS/OCS/Coast Survey Development Laboratory

CBOFS2 Total River Volume DischargeCriteria for Choosing Hindcast Period

Events/Wet Periods

Dry Periods

Synoptic Hindcast simulation period : June 01, 2003 – August 31, 2005

NOAA/NOS/OCS/Coast Survey Development Laboratory

Initialization FieldsModel spun-up from rest : water elevations,

currents zero and T, S non-zeroFor latitude ≤ 39.2o N, for T, S fields used

WOA2001 climatology for the Bay axis region and for tributaries used CBP observations (blended via bi-linear interp.)

For latitude ≥ 39.2o N, for T, S fields used only CBP observations (CBP data more abundant and better)

Interpolated the T, S in the vertical linearlyInitialization date : June 01, 2003 (0000 hrs

GMT)

NOAA/NOS/OCS/Coast Survey Development Laboratory

CBOFS2 River Forcing - I

River volume discharge adjustment factors (Wen Long)

NOAA/NOS/OCS/Coast Survey Development Laboratory

CBOFS2 River Forcing - II• River volume discharges from USGS• River forcing at daily frequency• Discharges ramped-up in time over 5-day period (linearly)• Discharges distributed vertically according to parabolic profile• When rivers distributed over multiple cells, discharge scaled by cross- sectional area• Some tributaries combined (e.g. Susquehanna, Choptank, Patuxent, etc.)• Rivers non-tidal• River T and S from CBP data for 2003- 2005

NOAA/NOS/OCS/Coast Survey Development Laboratory

CBOFS2 Meteorological Forcing• NARR blended (via interpolation) observations for winds, air T, air P and RH (via DP)• Forcing fields are hourly• Avoid using NARR values on land for winds, air T, RH and down. SW• Delete NARR grid nodes near obs. to facilitate more effective blending• Winds at 10m, air T, RH at 2m and LW down, net SW, air P at surface• Use 80% of NARR SW after compar- ing with observations• Ramp-up winds over 5-days (linearly)• ROMS internally interpolates met. fields via bi-cubic interpolation

NOAA/NOS/OCS/Coast Survey Development Laboratory

CBOFS2 Open Boundary Forcing Open boundaries selected to be pinned at Duck, NC and Ocean

City, MD because of observations For water elevations on shelf boundary use ADCIRC harmonics for

tides with non-tidal contribution from two corners (interpolated) ADCIRC harmonics adjusted at two corners to match observations

exactly using ℮-5x scaling function along CBOFS2 open boundary For C & D canal water elevations, use Reedy Point total elevations On shelf boundary use ROMS reduced OB conditions so no need

for currents; at C & D OB, use currents from tidal prediction with NOS Stn. 154 (1984 survey) harmonics

For T, S on shelf boundary use WOA 2001 climatology For T, S at C & D canal boundary use values from USGS station

0142800 which is within DE Bay T, S forcing is daily and water elevation and currents is 6-minutely

(NOS standard)Forcing again ramped-up over 5-day period (linearly)