Climate Change Parameters (PDF)

Climate Change Risk Assessment Study 
TOWN OF WATERFORD , CONNECTICUT 
Preliminary Phase I Results 
October 28, 2016 

Phase I: Establish Parameters 
Goal: Develop appropriate climate change 
scenarios for: 
Tide 
Storm surge  
Heavy rainfall 
2 

Time Horizons 
Present 
2016 
• Baseline climate conditions 
• Priority adaptation strategies  
Medium Term 
2030 
• More certain climate change projections 
• Incremental and opportunistic adaptation strategies 
Longer Term 
2070 
• Less certain climate change projections 
• Large, complex, costly adaptation strategies 
3 

IMPACT OF SEA LEVEL RISE 
ON TIDE AND STORM SURGE 
4 

National Climate Assessment:  
Global Sea Level Rise (SLR) Scenarios 
Assumptions 
Scenarios 
Glacier and ice sheet melt  
Ocean thermal expansion  
Highest SLR 
High 
High 
Intermediate-High SLR 
Low 
High 
Intermediate-Low SLR 
Low 
Low 
5 

Relative SLR Projections for 
Waterford (2016-2100) 
Time horizons (year) and projections (feet) 
Scenarios 
2020 2030 2040 2050 2060 2070 2080 2090 2100 
Highest SLR 
0.1 
0.6 
1.1 
1.7 
2.4 
3.2 
4.2 
5.2 
6.3 
Intermediate-High SLR 
0.1 
0.4 
0.7 
1.1 
1.5 
2.0 
2.5 
3.2 
3.8 
Intermediate-Low SLR 
0.0 
0.1 
0.1 
0.2 
0.3 
0.4 
0.4 
0.5 
0.6 
6 
Table reports feet of relative sea level rise since 2016. 

Daily High Tide with SLR 
7 
1.4 
2.0 
4.6 
1990 
2000 
2010 
2020 
2030 
2040 
2050 
2060 
2070 
2080 
2090 
2100 
0.0 
1.0 
2.0 
3.0 
4.0 
5.0 
6.0 
7.0 
8.0 
9.0 
MEAN HIGHER HIGH WATER (MHHW) ELEVATION 
(FT. NAVD88) 
Highest SLR 
Intermediate-High SLR 
Intermediate-Low SLR 
Observed 
Observed data are from the NOAA tide gage in New London, CT. 

Niantic River Coastal Water Elevations: 
Storm Surge with SLR 
8 
10.0 
10.6 
13.3 
2016 
2030 
2070 
0.0 
2.0 
4.0 
6.0 
8.0 
10.0 
12.0 
14.0 
16.0 
18.0 
COASTAL WATER ELEVATION 
(FT. NAVD88) 
Daily 
Annual 
10-Year 
100-Year 
1,000-Year 
Hurricane Sandy 
Preliminary projections 

Present Coastal Water Elevations 
Across Waterford 
9 
10.0 
9.0 
9.1 
9.9 
Niantic River 
Niantic Bay 
Jordan River 
Thames River 
0.0 
2.0 
4.0 
6.0 
8.0 
10.0 
12.0 
14.0 
16.0 
COASTAL WATER ELEVATION  
(FT. NAVD88) 
Daily 
Annual 
10-Year 
100-Year 
1,000-Year 
Preliminary projections 

100-Year Coastal Water Elevations Across 
Waterford: Storm Surge with SLR 
10 
10.0 
10.6 
13.3 
8.0 
9.0 
10.0 
11.0 
12.0 
13.0 
14.0 
2016 
2030 
2070 
100-YEAR COASTAL WATER ELEVATION 
(FT. NAVD88) 
Niantic River 
Niantic Bay 
Jordan Cove 
Thames River 
Preliminary projections 

Developing Climate Change 
Projections for Heavy Rainfall 
1. Downscaled Data Sources 
2. Geographic Scope 
3. Emissions Scenarios 
4. Global Climate Models 
5. Temporal Variability 
11 

 
 
 
 
 
Baseline period ≈ NOAA 
Atlas 14 design storms 
Higher resolution model 
Downscaled Data Source 
12 
Geographic Scope 

Climate Models and Scenarios 
13 
Emissions Scenarios 
Global Climate Models 
1. bcc-csm1-1-m 
2. CanESM2 
3. CCSM4 
4. CNRM-CM5 
5. CSIRO-Mk3-6-0 
6. GFDL-ESM2M 
7. HadGEM2-CC365 
8. inmcm4 
9. IPSL-CM5A-MR 
10. MIROC5 
11. MRI-CGCM3 

Baseline and Projected Rainfall 
Design Storms in Waterford 
14 
10-Year 
10-Year 
10-Year 
25-Year 
25-Year 
25-Year 
100-Year 
100-Year 
100-Year 
0 
4 
8 
12 
Baseline 
2030 
2070 
Precipitation Depth (in) 

Percent Increase from Baseline 
Median 
Storm NOAA 
% Increase from 
baseline for 2030 
2030 depth 
(in) 
% Increase from 
baseline for 2070 
2070 depth 
(in) 
10-Year 
5.14 
6.1% 
5.45 
16.8% 
6.00 
25-Year 
6.19 
8.6% 
6.73 
21.4% 
7.51 
100-Year 7.81 
6.8% 
8.34 
29.5% 
10.11 
15 

Maps to be Produced in Phase II 
for Study Time Horizons 
Flood depth:  
Mean higher high water (tide) with SLR 
100-year coastal water elevation (storm 
surge) with SLR 
100-year 24 hour rainfall design storm 
Flood probability 
Coastal water elevation (storm surge) with 
SLR 
16