HomeMy Public PortalAboutCC_MappingSea Level Rise and Storm
Surge
Mapping
Components
Shoreline
Change
Over
Time
Sea
Level
Rise
Storm
Surge
Sea
Level
Rise
Relevant
Literature
U.S.
Inter-‐agency
report:
NOAA
SERDP
–
itself
an
inter-‐
agency
organization
with
DOD,
EPA,
and
DOE
USGS
US
Army
Corps
Why
This
Report?
Based
in
science
Its
global
SLR
scenarios
recognized
for
SLR
vulnerability
assessments
by:
The
MA
Climate
Change
Adaptation
Report
MA
CZM
MA
DOT
Only
coordinated
interagency
effort
in
the
US
What
are
its
SLR
Scenarios?
Why
so
much
variability?
Scenario
SLR
by
2100
(2)
Summary
Highest
6.6
Derived
from
ocean
warming
and
maximum
ice
sheet
loss
Intermediate/High
3.9
Based
on
limited
ice
sheet
loss
plus
ocean
warming
Intermediate/Low
1.6
Based
primarily
on
SLR
from
ocean
warming
Lowest
0.7
Linear
extrapolaLon
of
historical
SLR
rate
derived
from
Lde
gauge
records
What
Historical
SLR?
Historic
Sea
Level
Gauge
Data
from
Boston
Harbor
2
More
Gauges:
Woods
Hole
(2.83
mm
+/-‐
0.18
mm/yr)
Nantucket
(3.58
mm
+/-‐
0.39
mm/yr)
Making
Global
SLR
Local
U.S.
National
Climate
Assessment
(2012)
estimates
future
global
SLR
Tidal
gauge
data
provide
historical
local
SLR
U.S.
Army
Corps
developed
a
Sea
Level
Change
Calculator
to
incorporate:
Future
global
SLR
estimates
with
Local
tidal
gauge
data
SLR
Scenarios
–
Boston
Gauge
Source:
U.S.
Army
Corps
of
Engineers
(USACE)
Sea
Level
Change
Curve
Calculator,
Version
2015.46
What
is
a
storm
surge?
An
abnormal
rise
of
water
generated
by
a
storm,
over
and
above
the
predicted
astronomical
tides.
Source:
NOAA
National
Hurricane
Center
Why
Storm
Surges
MaRer
Can
happen
today,
tomorrow,
next
year
Depending
on
the
storm,
surges
can
reach
10-‐15
feet
They
are
cumulative
(additive),
over:
High
tides
SLR
Coastal
change
processes
A
Storm
Surge
Model
-‐
SLOSH
The
National
Weather
Service’s
Sea,
Lake
and
Overland
Surges
from
Hurricanes
(SLOSH)
model
Computerized
numerical
model
Estimates
storm
surge
heights
resulting
from
historical,
hypothetical,
or
predicted
hurricanes
Takes
into
account
atmospheric
pressure,
size,
forward
speed,
and
track
data
Cat
2
SimulaLon,
Mean
High
Tide
SLOSH
Storm
Surge
Heights
Hurricane
Category/ Tide Mean High
(2 ft tide)
High
(5 ft tide)
1 0-2.1 ft 4.1-4.9 ft 7.1-7.8 ft
2 4.7-6.3 ft 6.6-8.2 ft 9.7-11 ft
3 8.8-10 ft 10.9-11.7 ft 14.1-14.6 ft
4 11.8-13.4 ft 13.9-15.1 ft 17.1-17.7 ft
VisualizaLons
Town-‐Wide
(GIS
and
Aerial-‐based)
Expected/extrapolated
coastal
change
SLR
Storm
surges
Landing
visualizations
(Photo-‐based)
SLR
and
storm
surges
Crosby
Landing
Saint’s
Landing
Paine’s
Creek,
Mant’s
Landing
AdapLve
Planning
ConsideraLons
Impacts
Will
Vary
Along
the
Coast
–
So
Adaptive
Plans
Will
Vary
Daily
Impacts
of
SLR
Versus
Less
Frequent,
But
Larger
Storm
Surge
Impacts
–
Daily
Nuisance
Versus
Extreme
Event
The
AdapLve
Planning
Spectrum
Do
Nothing
Vegetation
Management
Regrade/Clean
up
After
Storms
Erosion
Control
Structures
Beach
Nourishment
Managed
Retreat
Planning
ConsideraLons
Compliance
with
the
Wetlands
Protection
Act
Parking
Locations
Extent
of
Access
QuesLons?