Coastal Flooding and Erosion from Severe Storms in a Changing Climate Qingping Zou and Dongmei Xie, University of Maine John Cannon, National Weather Service
Coastal flooding at Saco, ME Coastal Erosion Saco, ME during Patriot's Patriot's Day Storm in April 2007 Day Storm in April 2007 ----- $ 20 Million Damage Partners: Stephen Dickson (MGS), Will Perrie (BIO),Vijay Panchang (TX) Outreach Climate Change-Sea Level Rise -2 feet of sea level rise over the next 100 years for Maine
By Stephan Dickson and Peter Slovinsky (Maine Geological Survey) Climate Change -Larger and more frequent storm
Old Orchard Beach Maine
York Beach MaineYork Beach Maine Objective I
To improve the real-time wave and coastal flooding and erosion forecast at the coast of Maine during extreme storms:
! Early warning and evacuation to save lives and property
! Protect coastal infrastructure
! Safe and efficient marine operations and maritime activities
Objective II
To produce “dynamic” coastal inundation maps with and without sea level rise that include wave set-up, run-up and overtopping/splash-over :
! Identify areas threatened by coastal flooding risks
! Plan strategies to adapt to future coastal hazard in a changing climate To Build Resilient Coastal Community ! Inundation Map
By Peter Slovinsky (MGS) “Clouds-to-coast” Modelling Framework of Coastal Flood Risk
1. Weather forecasting model 2. Tide, surge & wave models 3. Surf zone models “Clouds-to-coast” Modelling Framework of Coastal Flood Risk
Atmospheric Wave, Surge, Tide Nearshore Surf Zone Models Models wave Models heights Water elevation North American UNSWAN FUNWAVE Mesoscale weather model Dune erosion Offshore Wave wave, Radiation model surge, tide stress and heights gradients WRF ADCIRC Surface wind and Coastal inundation, pressure Wave run-up splash-over and erosion Unstructured Grid for the Gulf of Maine
Grid size: 25 km offshore Bathymetry and topography 10 m Coast Node: 0.2 Million Element: 0.4 Million
Unstructured Grid for Old Orchard Beach
Old Orchard Beach Saco
Biddeford Patriot’s Day Storm of 2007
" Category II hurricane
" 70 m/s Peak gust wind
" 1 m storm surge
" 9 m wave height
" coastal flooding and severe erosion southern Maine
Created using North American Regional Reanalysis data Wave Predictions -Structure and unstructure grid
Western Maine Shelf Central Maine Shelf 44032 (E01) 44030 (B01) 8 8 Obs Obs SWAN-Sturctured SWAN-Sturctured ADCIRC-UnSWAN ADCIRC-UnSWAN 6 6
4 4 Hs (m) Hs (m)
2 2
0 0 4/15/2007 4/16/2007 4/17/2007 4/18/2007 4/15/2007 4/16/2007 4/17/2007 4/18/2007 Date Date 44032 (E01) 44030 (B01) 20 20 Obs Obs SWAN-Sturctured SWAN-Sturctured 16 16 ADCIRC-UnSWAN ADCIRC-UnSWAN 12 12 Tp (s) Tp Tp (s) Tp 8 8
4 4
0 0 4/15/2007 4/16/2007 4/17/2007 4/18/2007 4/15/2007 4/16/2007 4/17/2007 4/18/2007 Date Date Tide Predictions
OBS 8418150 ADCIRC 3 Portland, ME 2 1 0 -1 Tidal (m) level Tidal -2 OBS 8452660 ADCIRC -3 3 4/15/2007 4/16/2007 4/17/2007 4/18/2007 Newport, RI Date 2 OBS 8423898 1 ADCIRC 3 Fort Point, NH 0 2 -1
1 (m) level Tidal -2 0 -3 -1 4/15/2007 4/16/2007 4/17/2007 4/18/2007 Tidal level (m) level Tidal -2 Date -3 4/15/2007 4/16/2007 4/17/2007 4/18/2007 Date Storm Surge Predictions OBS 8418150 ADCIRC 1 Portland, ME
0.6
Surge (m) Surge 0.2
OBS 8452660 -0.2 ADCIRC 1 4/15/2007 4/16/2007 4/17/2007 4/18/2007 Date Newport, RI OBS 8423898 0.6 ADCIRC 1 Fort Point, NH
Surge (m) Surge 0.2 0.6
-0.2
Surge (m) Surge 0.2 4/15/2007 4/16/2007 4/17/2007 4/18/2007 Date
-0.2 4/15/2007 4/16/2007 4/17/2007 4/18/2007 Date Bay of Fundy
Jordan Wind and Waves Predictions Basin Scotian Shelf Wilkinson Basin Georges Basin Georges Nantucket Bank shoals
Wind Waves Wave Prediction at Casco Bay Wind and Wave Prediction -Inner Penobscot Bay
Wind Wave
19 Bay of Fundy
Jordan Wind and Surge Predictions Basin Scotian Shelf Wilkinson Basin Georges Basin Georges Nantucket Bank shoals Bay of Fundy
Jordan Coastal Inundations at Saco Bay Basin Scotian Shelf Wilkinson Basin Georges Basin Georges Nantucket Bank shoals Nearshore Circulation at Saco Bay
1200UTC 16 April 2007
Without wave With Wave Conclusions
" The predicted tide, storm surge and wave compare well with the field measurements " The model on unstructured grid improves the predicted wave height and period due to the complicated bathymetry at the GoM " The nearshore circulation was enhanced by the presence of wave " The model is capable to provide accurate real-time forecasts of wave, surge and coastal flooding 4-level nested SWAN model in GoM
! High resolution bathymetry: 90 m Gulf of Maine (DEM)
# Domain L1 L4 $ L1: Gulf of Maine L2 (11 km) L3 $ L2: Maine coast
(2.8 km)
$ L3: Penobscot Bay
(550 m)
$ L4: Inner Penobscot Bay (110 m)