CDMP Storm Hazard Atlas: Grenadines

1
The Grenadines Probable Storm Effects
St. Vincent
Bequia
Admiralty Bay
1
Points of Interest
Mustique
1. Admiralty Bay Deep-water harbour with
village. Values listed are for a cell out to sea
on the west, since the harbour does not appear at
this resolution
2. Hillsborough Village on a shallow lagoon.
Canouan
Mayreau
Note Waves and surges for Points of Interest
are reported from the nearest cell offshore.
Union
The projection of the illustrations is Plate
Carrée, a square grid of latitude and longitude.
Resolution is 30 arc-seconds. North-South
distances are true to scale. East-West distances
are stretched 2.3 at 12.15 degrees North, and
stretched 2.7 at 13.2 degrees North. All model
results were calculated using great-circle
distances based on the WGS84 datum.
2
Hillsborough
Note Several small islands appear co-joined at
this resolution.
Carriacou
N
Grenada

• This set of maps is part of Section 2 of the
  Atlas of Probable Storm Effects in the Caribbean
  Sea, which was sponsored by the Caribbean
  Disaster Mitigation Project (CDMP), a joint
  effort of the Organization of American States
  (OAS) and the US Agency for International
  Development (USAID). These maps are a result of
  new techniques for modeling storms and
  estimating the probabilities of storms, developed
  in part under the patronage of CDMP. Refer to
  the Atlas for explanatory materials.
• WINDS represent sustained 1-minute winds at 10 m
  above the surface, and include both surface
  friction and topographic effects at a resolution
  of 30 arc-seconds. Friction factors derive from
  a Level I land-cover classification, with water,
  forest and open land predominating. If using
  wind damage models or building codes which
  internally include surface friction or
  topographic corrections, the nearest open-water
  wind speed from one of these maps may be used as
  input. Careful judgement is advised in reading
  and applying the values.
• SURGES include astronomical tide and setups from
  pressure, wind and wave, but not wave runup.
  Surges over land are shown as elevation above sea
  level, not water depth.
• WAVES are the heights of wave crests above the
  storm surge level in open water. Shoreline
  effects do not appear at this resolution.

2
Winds
10-Year Return Time
The Grenadines
1
1. Admiralty Bay 25 m/s
2. Hillsborough 23 m/s
2
N
3
Waves
10-Year Return Time
The Grenadines
1
1. Admiralty Bay 3.1 m
2. Hillsborough 2.8 m
2
N
4
Surges
10-Year Return Time
The Grenadines
1
1. Admiralty Bay 0.1 m
2. Hillsborough 0.0 m
2
N
5
Winds
25-Year Return Time
The Grenadines
1
1. Admiralty Bay 32 m/s
2. Hillsborough 30 m/s
2
N
6
Waves
25-Year Return Time
The Grenadines
1
1. Admiralty Bay 4.1 m
2. Hillsborough 3.8 m
2
N
7
Surges
25-Year Return Time
The Grenadines
1
1. Admiralty Bay 0.2 m
2. Hillsborough 0.1 m
2
N
8
Winds
50-Year Return Time
The Grenadines
1
1. Admiralty Bay 38 m/s
2. Hillsborough 35 m/s
2
N
9
Waves
50-Year Return Time
The Grenadines
1
1. Admiralty Bay 4.7 m
2. Hillsborough 4.4 m
2
N
10
Surges
50-Year Return Time
The Grenadines
1
1. Admiralty Bay 0.3 m
2. Hillsborough 0.2 m
2
N
11
Winds
100-Year Return Time
The Grenadines
1
1. Admiralty Bay 43 m/s
2. Hillsborough 40 m/s
2
N
12
Waves
100-Year Return Time
The Grenadines
1
1. Admiralty Bay 5.4 m
2. Hillsborough 5.1 m
2
N
13
Surges
100-Year Return Time
The Grenadines
1
1. Admiralty Bay 0.4 m
2. Hillsborough 0.4 m
2
N