Ian Church Ocean Mapping Group University of New Brunswick US Hydro 2007 The Sixth International Discussion Group Meeting on Uncertainty Management in Hydrography

Saint John Digby St. Andrews Grand Manan Eastport 2

Tidal Range and Phase Survey Operations up to 2006 Deer Island Campobello Island The Wolves St. Andrews Eastport m 2.3 m Passamaquoddy Bay Maces Bay M2 Amplitude and Phase WebTide Scotian Shelf Model 1 Minute Phase Contours M2 Amplitude and Phase WebTide Scotian Shelf Model 1 Minute Phase Contours 8 Minute Phase Lag Through Letite Passage 0 km10 km20 km

White – 0.2m range contours. Black 1 minute phase ranges. 4 Operations 2007 Grand Manan M2 Amplitude and Phase WebTide – Scotian Shelf Model Contours: 1 Minute Phase 0.2 m Amplitude

 Tides: Observed Tides Predicted Tides Hydrodynamic Model  Sounding Datums: MSL / Geoid Local Chart Datum  Discrete Steps?  Linear Transition?  Polynomial Interpolation? Co-Tidal Interpolations Scaled Multiple of the Local Harmonic Constituents 5 We wish to establish a vertical datum which represents an offset from mean-sea-level, below which “the tide rarely falls”.

Tides in the Bay of Fundy wrt Saint John Options: Use Predicted Tides Interpolate Between Stations Outer Wood Island -15 minutes -9.5ft North Head -5 minutes -5.5ft Dipper Harbour -2 minutes -2.6ft St. Andrews +8 minutes -2.5ft St. Stephen +8 minutes -1.0ft Partridge Is. -13 minutes -0.3ft Welshpool +1 minutes -4.2ft Back Bay -7 minutes -3.8ft St. Martins +6 minutes +6.3ft Cape Enrage +5 minutes +13.2ft Hopewell Cape +8 minutes +18.5ft Moncton +45 minutes +26.2ft Advocate Harbour +5 minutes +10.3ft Saint John Primary Port 0 minutes Mean Tide – 25.3ft (7.7m) Large Tide – 29.6ft (9.0m) Margaretsville -18 minutes +7.6ft Digby -16 minutes +1.0ft Brier Island -44 minutes -8.3ft Source: Canadian Tide and Current Tables Atlantic Coast and Bay of Fundy EastPort ME USA Primary Port 6

 A Digital Replica of the Water Within a Region  Created using a Coastline and Seafloor Bathymetry  Driven Using Topex- Poseidon Tidal Observation Data and Tide Gauge Data 7 Scotian Shelf Model Bay of Fundy Nova Scotia Maine  A TIN of the Scotian Shelf, Georges Bank and the Bay of Fundy DUPONT, F.; C.G. HANNAH, D.A. GREENBERG, J.Y. CHERNIAWSKY and C.E. NAIMIE Modelling system for tides for the North–west Atlantic coastal ocean. Can. Tech. Rep. Hydrogr. Ocean Sci. 221:vii+72pp.

 Provides a Tidal Prediction for any point within the TIN  Predicted Amplitude and Phase  Tidal Currents  Accuracy 0.15 metres Amplitude 5 deg Phase 8 Dupont, F., C. G. Hannah, D. Greenberg. Modelling the sea level in the upper Bay of Fundy. Atmosphere-Ocean 43(1) 2005,

9 Meteorological Effects – Pressure, Wind/Wave Build up, etc. Non-Tidal Residuals Digby Saint John Eastport Cutler Brier Island North Head North Head Yarmouth

Cutler Naval Base - Maine Digby – Nova Scotia Eastport - Maine Brier Island – Nova Scotia 0km25km50km100km 10  All Tide Stations within the Area Display Very Similar Non-Tidal Residuals  Non-Tidal Residuals from a Single Station can be Examined

 Sounding Datum that Varies Constantly and Smoothly throughout the Entire Model Domain  Based off the Tidal Prediction at Each Node within the TIN Develop Sounding Datum Based on Hydrodynamic Model 11 Bay of Fundy Nova Scotia Maine

 Relate ISLW to Existing Chart Datum  Determine Multiplier at Local Tide Stations  Datum = Multiplier * ISLW  Indian Spring Low Water Suggested by Sir George Darwin for Indian Waters ISLW = MSL – (M 2 +S 2 +K 1 +O 1 ) 12 S2S2 M2M2 K1K1 O1O1 ISLW Datum Saint Andrews M S K O Sum3.400 Zo3.871 Multiplier1.14 Great Britain Hydrographic Office (1969). “Tides and Tidal Streams.” Chapter Two in Admiralty Manual of Hydrographic Surveying, Vol. 2, Somerset, England, 118pp.

 Datum = F*S where, If (S < 2 m) F = 0.85 If (S > 5 m) F= 1.0 Else F is linearly interpolated between the above values. 13 S2S2 M2M2 K1K1 O1O1 N2N2  Hannah, DFO S = M 2 +N 2 +S 2 +K 1 +O 1 Datum

14 RMS = 0.22 mRMS = 0.30 m 38 CHS Tide Stations

 Tidal Power Stations  Perform Repeat Surveys Prior to Installation to Observe Existing Sediment Transport 15 Deer Island Campobello Island Eastport Passamaquoddy Bay

 Provides a Smooth Sounding Datum Throughout the Model  Uniform Transitions Between Datasets  Datum Based on Varying Predicted Tides Throughout the Region Resolve Tides from Hydrodynamic Model + Non Tidal Residuals Sounding Datum based on Hydrodynamic Model Resolve Tides from Hydrodynamic Model + Non Tidal Residuals Sounding Datum based on Hydrodynamic Model 16

Ian Church

18 Day 1 = Black Day 2 = Red Hydrodynamic Model Tide Black’s Harbour Tide Wilsons Beach Tide St. Andrew’s Tide Eastport Tide Fairhaven Tide Separation30cm80cm90cm2cm35cm40cm Multibeam Sonar Swath