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Predictions of the Climate Change-Driven Exodus of the Town of Tangier, the Last Offshore Island Fishing Community in Virginia's Chesapeake Bay

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Abstract

Sea-level rise (SLR) has been confirmed to be accelerating globally due to human-influence driven climate change. Multiple studies suggest many coastal communities will soon be inundated by SLR. Prior to inundation, habitable uplands above the high tide line first convert to uninhabitable wetlands, forcing human exodus. Habitability, not the land's presence above the low tide line, drives exodus. We determined the time left for uplands of the Town of Tangier of VA, USA to be converted to wetlands, analyzed local sea level rise data to determine the best local SLR scenario (low, mid, or high) fit, then compared upland conversion rate to the rate of population decline. The upland landmass constituting the Town of Tangier declined from 32.8 to 12.5 ha (1967–2019), accelerating over time, with complete conversion to wetlands predicted by 2051. The US Army Corps of Engineers (USACE) high SLR curve is the best fit to the local tide gauge's raw data (1967–2020), indicating local sea level rise has rapidly accelerated in recent decades, concomitant with the rate of wetland conversion. The Town's population, in decline since the 1930s, accelerated rapidly after 1980 and trended downward in tandem with the conversion of the Town's uplands to wetlands. We also estimated costs to relocate the Town as well as for a conceptual plan to provide long-term stability to the Town and Island of Tangier.
ORIGINAL RESEARCH
published: 08 November 2021
doi: 10.3389/fclim.2021.779774
Frontiers in Climate | www.frontiersin.org 1November 2021 | Volume 3 | Article 779774
Edited by:
Swadhin Kumar Behera,
Japan Agency for Marine-Earth
Science and Technology
(JAMSTEC), Japan
Reviewed by:
Hajime Kayanne,
The University of Tokyo, Japan
Shion Sekizawa,
The University of Tokyo, Japan
*Correspondence:
David Schulte
David.M.Schulte@usace.army.mil
These authors have contributed
equally to this work and share first
authorship
Specialty section:
This article was submitted to
Predictions and Projections,
a section of the journal
Frontiers in Climate
Received: 19 September 2021
Accepted: 20 October 2021
Published: 08 November 2021
Citation:
Wu Z and Schulte D (2021)
Predictions of the Climate
Change-Driven Exodus of the Town of
Tangier, the Last Offshore Island
Fishing Community in Virginia’s
Chesapeake Bay.
Front. Clim. 3:779774.
doi: 10.3389/fclim.2021.779774
Predictions of the Climate
Change-Driven Exodus of the Town
of Tangier, the Last Offshore Island
Fishing Community in Virginia’s
Chesapeake Bay
Zehao Wu and David Schulte*
Biogenic Solutions Consulting, LLC, Newport News, VA, United States
Sea-level rise (SLR) has been confirmed to be accelerating globally due to human-
influence driven climate change. Multiple studies suggest many coastal communities will
soon be inundated by SLR. Prior to inundation, habitable uplands above the high tide
line first convert to uninhabitable wetlands, forcing human exodus. Habitability, not the
land’s presence above the low tide line, drives exodus. We determined the time left for
uplands of the Town of Tangier of VA, USA to be converted to wetlands, analyzed local
sea level rise data to determine the best local SLR scenario (low, mid, or high) fit, then
compared upland conversion rate to the rate of population decline. The upland landmass
constituting the Town of Tangier declined from 32.8 to 12.5 ha (1967–2019), accelerating
over time, with complete conversion to wetlands predicted by 2051. The US Army Corps
of Engineers (USACE) high SLR curve is the best fit to the local tide gauge’s raw data
(1967–2020), indicating local sea level rise has rapidly accelerated in recent decades,
concomitant with the rate of wetland conversion. The Town’s population, in decline since
the 1930s, accelerated rapidly after 1980 and trended downward in tandem with the
conversion of the Town’s uplands to wetlands. We also estimated costs to relocate the
Town as well as for a conceptual plan to provide long-term stability to the Town and
Island of Tangier.
Keywords: sea level rise, Tangier Island, exodus, population, climate change, uplands, wetlands, conversion
INTRODUCTION
The Intergovernmental Panel on Climate Change [IPCC Sixth Assessment Report (AR6)] asserted
that “It is unequivocal that human influence has warmed the atmosphere, ocean and land.
Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred
(IPCC, 2021). The IPCC also noted that since the beginning of the Industrial Revolution, the global
mean sea level rise (SLR) rose significantly and has been accelerating, posing an existential threat to
many island (Farbotko, 2010) and coastal communities. The inhabited Tangier Island, in the middle
of Chesapeake Bay, USA, is one of those threatened islands and is the focus of this study (Figure 1).
The Chesapeake Bay is the largest estuary in the United States, located on the Mid-Atlantic
region of the East Coast, separated from the Atlantic Ocean by the Delmarva Peninsula (see
Wu and Schulte Climate Change-Driven Tangier Exodus
FIGURE 1 | Location and configuration of the Tangier Island and the Town of
Tangier, in Virginia waters of Chesapeake Bay, USA. Source: Schulte et al.
(2015).
Supplementary Figure 1), lands occupied by the State of
Delaware, and the Eastern Shore region of the State of Maryland
and the Commonwealth of Virginia. The Bay’s northern half lies
within the borders of the State of Maryland, the southern half
within the Commonwealth of Virginia. It is a drowned river
valley, inundated as glaciers melting at the end of the last Ice Age.
Most of its waters are shallow, with the average depth being 7 m
and the deepest waters are 53 m. At the time of initial European
settlement (1600s), the Bay had hundreds of islands (1–800 ha
in size); however, few of the islands were ever inhabited with
a permanent population, mostly due to the lack of sufficient
habitable uplands. Since the 1600s, more than 500 islands have
been lost to SLR and erosion, this loss continues to this day
(Cronin, 2005). One of the permanently settled islands is now the
last remaining inhabited offshore island in Virginias Bay waters,
the Town of Tangier, on Tangier Island. Tangier Island lies near
the end of a sunken peninsula that was inundated as the last
Ice Age ended and waters rose due to glacial melting. Being an
offshore Island, Tangier does not have a significant source of sand,
unlike a barrier island. Tangier and other islands ranging north
along the highest points of the former peninsula are typically
entirely composed of sand, silts and clay, which also extends 10 m
below the Islands and Bay bottom. Underneath the first 10 m
of sediments is typically sand with clay lenses and occasional
FIGURE 2 | The three upland ridges of the Town of Tangier’s upland area in
1967–2015 visualizing the extent of conversion. Map created using Esri
ArcGIS, ArcMap 10.8. Source: USDA Farm Service Agency. Area found within
the red rectangle of Figure 1.
shell deposits until bedrock which is found much further below.
The only hard substrate in the local area are oyster reefs, which
range from intertidal to 10 m below the surface. Water depths
around the island are shallow, typically <5 m deep within 1 km
of the shoreline, with deeper channels of drowned river valleys
with waters <10 m deep located offshore on both the East and
West side of Tangier Island. Local tides are semi-diurnal with an
average range of 0.37 m. The Island, originally settled in the 1770s
by European colonists as a farming community, held significant
forested uplands at the time but is now made up of mostly
estuarine wetlands and three (seven at settlement) major sandy
upland ridges (Heywood and Pope, 2009; Yarrington, 2020).
Farming is now no longer possible due to the lack of suitable
land to do so and most of the trees on the Island, including
the Town, have died due to saltwater intrusion. The Town has
been primarily a fishing community (fishers are locally known
as “watermen”) since the mid-1800s, due to the higher potential
income earned by fishing vs. farming (Cronin, 2005; Yarrington,
2020). As of 2020, the island is estimated to have a population
of 436 (US Census Bureau, 2020), having shrunk from a peak of
over 1,100 people in the early 1900s.
The Town consists of three upland ridges, from west to
east, respectively: West, Main, and Canton (Figure 2). Their
topography is mostly flat; however, there are several patches
of higher ground, concentrated mostly on Canton and the
northern tip of the Main ridge (Tangier Planning Commission,
1996) that range up to 1.51 m above mean higher high water
(MHHW). Most of the Town’s uplands are <1.0 meters above
MHHW, lying within the US Federal Emergency Management
Agency (FEMA) flood zone AE, a special flood hazard area
well within the 100-year flood plain, and the highest ground
in the Town is classed as Zone X (1.0 m MHW), which is
a moderate flood risk area, lying between the 100 year and
500-year flood plain (Figure 3). The entire Tangier airport
was elevated using dredged material and it currently one of
the highest points on the Island, much of it lying in Zone
Frontiers in Climate | www.frontiersin.org 2November 2021 | Volume 3 | Article 779774
Wu and Schulte Climate Change-Driven Tangier Exodus
FIGURE 3 | FEMA flood map depicting the highest uplands (flood zone X) of the Town of Tangier in brown, and illustrating the whole island, including the majority of
the Town’s uplands is considered to be in flood zone AE. Source: FEMA (2021). Area found within the red rectangle of Figure 1.
FIGURE 4 | Regressions of the upland to wetland conversion rate of the three
upland ridges [West (triangles), main (open circles), and Canton (filled circles)].
West Ridge: (y= −5.04x2+18,715x – 1,72,00,000), (r2=0.994 and p<
0.05 for all parameters). Main Ridge: (y= −30.4x2+119133x –
11,70,00,000), (r2=0.97 and p<0.05 for all parameters). Canton Ridge:
(y= −552x +11,30,000), (r2=0.991 and p<0.05 for all parameters).
X. Outside of the Town, the remaining lands are in flood
zone VE, classed as lands <1.0 m above MHHW and also
vulnerable to storm waves. Due to the man-made characteristics
of the airport uplands, this area will not be considered as
FIGURE 5 | Low (blue), mid (green), high (red) SLR curves of the USACE
compared with the raw data of Sewell’s Point Tide Gauge (black) from
1967–2020. The equation for Sewell’s point raw data is y=0.00005765x2
0.223x +216.869 (r2=0.57 and p<0.05 for all parameters).
part of the natural, original ridges and was not included in
our measurements.
Analysis in the AR6 report states that “Global mean sea level
increased by 0.20 [0.15 to 0.25] m between 1901 and 2018. The
average rate of sea level rise was 1.3 [0.6 to 2.1] mm yr1between
Frontiers in Climate | www.frontiersin.org 3November 2021 | Volume 3 | Article 779774
Wu and Schulte Climate Change-Driven Tangier Exodus
FIGURE 6 | Regression of both the population decline and the overall rate of wetland conversion of all three ridges combined for the Town of Tangier. The filled circles
and the solid line represents the population decline. The open circle and the dashed line represent the overall wetland conversion rate. Population decline regression:
(y= −1,49,913.413 – 0.042x2+159.404x), (r2=0.96 and p<0.05 for all parameters). Overall wetland conversion rate regression: (y= −12,72,18,187.167 –
34.086x2+1,31,885.035x), (r2=0.99 and p<0.05).
1901 and 1971, increasing to 1.9 [0.8 to 2.9] mm yr1between
1971 and 2006, and further increasing to 3.7 [3.2 to 4.2] mm yr1
between 2006 and 2018 (high confidence).” Human influence
was cited as the unequivocal main driver of these SLR increases
since at least 1971 (IPCC, 2021). Locally, the RSLR (relative sea-
level rise) has been higher than the global mean, due to a SLR
“hotspot” that exists on the East coast of North America (Koeberl
et al., 1996; Kleinoksy et al., 2007; Barbosa and Silva, 2009; Yin
et al., 2009; Boon et al., 2010; Sallenger et al., 2012). The Southern
Chesapeake Bay region of this “hotspot” has a higher relative
rate of sea level rise (RSLR of 5.9 mm/yr from 1967 to 2019,
6.35 mm yr1from 2010 to 2020) compared to global mean
SLR (NOAA, 2020; IPCC, 2021), accelerating in tandem with the
global mean rate.
The amount of time until the southern Chesapeake Bay RSLR
converts the Town’s remaining uplands into wetlands, a process
known as Upland to Wetland Conversion, determines how long
the Town has until it will very likely have to be abandoned, due
to the lack of upland suitable for human habitation. Following
this conversion but prior to inundation, the Island will consist
entirely of wetlands. Prior studies (Kirwan et al., 2016; Schieder
et al., 2018; Schuerch et al., 2018) have shown that the wetland
area can stay relatively static in the Chesapeake Bay area, but
this is due to SLR converting nearby uplands to wetlands at a
similar rate that wave erosion and SLR destroy them (Schieder
et al., 2018) or sufficient sediment supply to maintain elevation
(Kirwan et al., 2016). However, in certain areas, wetlands are
lost during this process (Beckett et al., 2016). Unfortunately,
though this process may help maintain the wetland acreage
of the Island, it is at the expense of the Town’s Uplands,
which will not be replaced naturally due to lack of a source of
sediment to maintain present elevation. The conversion directly
threatens the inhabitants of the Town, as they will likely leave
as the Town is converted from habitable uplands to inhabitable
wetlands because there is nowhere else on the Island to build
housing above the high tide line other than the three ridges
currently inhabited.
Schulte et al. (2015) found that the Island has lost 66.75%
of its total landmass since 1850 (Schulte et al., 2015) due to
a combination of coastal erosion and RSLR, and predicted
that the Island would need to be abandoned between 2030
and 2065 due to additional loss of land from the Island’s
perimeter, stating that the Town of Tangier’s people would
be among the Continental USAs first climate change refugees.
However, they did not assess direct impacts of RSLR to
the Town itself, which is the main purpose of the present
study. The Schulte et al. (2015) study gained significant media
attention for Tangier Island and Town (Duhaime-Ross, 2016;
Gertner, 2016; Gray, 2017; Testa, 2018). This media attention
resulted in then-President Trump contacting Tangier’s mayor
and hypothesizing that Tangier Island had “hundreds of years
more” (Gray, 2017), a view shared by most of the Tangier
Islanders. We will assess this hypothesis, along with our own.
The majority of the Islanders deny the impact of climate
change and RSLR on the Island and Town, as did then-
President Trump, instead attributing the land losses experienced
since initial settlement-present entirely to coastal erosion. This
has contributed to the misinformation about climate change
regarding the reality, present severity, and predicted future
impacts of climate change and stimulated our interest in
conducting the present study.
Frontiers in Climate | www.frontiersin.org 4November 2021 | Volume 3 | Article 779774
Wu and Schulte Climate Change-Driven Tangier Exodus
FIGURE 7 | LIDAR survey of the southern portion of Tangier Island and the
Town of Tangier (2 feet =0.61 m, 4 feet =1.22 m, 6 feet =1.83 m). Source:
Accomac County. Imagery is from 2017.
Because the Town lies on upland ridges almost entirely inland
of the island’s shoreline, they are in large part (except for the
southern tip of West Ridge) protected from coastal erosion
and any loss of their area can be fully attributed to RSLR
(Figure 2). The present study will determine first whether there
has been any loss of uplands, and if so, the extent of and how
long the Town’s uplands have before complete conversion into
wetlands, which are not habitable land. Our hypotheses are that,
one: a significant amount of Town’s uplands have already been
converted to wetlands, two: that the time of full conversion to
wetlands will lie within the estimate by Schulte et al. (2015) for
Town abandonment, three: local RSLR is no longer following
the USACE’s low curve and will better fit the high curve, which
is causing the acceleration in wetland conversion, and four:
the Town’s population decline is correlated to the decline in
habitable uplands.
MATERIALS AND METHODS
High-resolution aerial photographs of Tangier Island were
extracted and analyzed with ArcGIS—a geo-referencing tool
provided by the Environmental Systems Research Institute (Esri).
The aerial imagery was provided by the US Geological Survey
(USGS), Esri, National Oceanic and Atmospheric Administration
(NOAA), US Department of Agriculture Farm Service Agency
(USDA), and the Commonwealth of Virginia. The earliest aerial
photograph with enough clarity to discern wetlands from the
Town of Tangier’s uplands was taken in 1967. Photographs
of similar quality were acquired from the years 1970, 1994,
2007, 2008, 2011, 2013, 2014, 2015, 2016, and 2019 and are
the subject of our analysis and the basis for our predictions for
The Town’s future (see Supplementary Figures 212). We were
able to measure accurately the upland areas from the 2016 and
2019 aerial imagery. Unfortunately, we were unable to extract the
2016 and 2019 imagery with high enough resolution from the
image owner to be presented on the map (Figure 2) illustrating
the upland area change up to 2019 but the underlying image is
from 2015.
To calculate the Town of Tangier’s rate of upland to wetland
conversion over time (1967–2019), we utilized the ArcGIS
Measure Tool to measure upland areas from the time series
imagery. The tool is controlled with the mouse cursor, and it
measures the area of the enclosed shape drawn. This is used to
trace around every patch of uplands of the three ridges to measure
the upland areas. Our study seeks to determine when the Town
will be abandoned due to the loss of all uplands for housing
and support infrastructure (the churches, school, medical facility,
shops, restaurants, water treatment, transportation, etc.). So,
therefore, only impacts of RSLR to the three inhabited ridges
of the Town of Tangier (32.8 ha in 1967) were considered,
uninhabitable areas were excluded. Uplands from each image
over time were determined and area calculated, including any
fragments of uplands that were separated within a given ridge
due to the upland to wetland conversion. The images came
from multiple authoritative sources, so we match the scaling
of each aerial image to ensure accuracy. The matching of the
scale was done by matching the shoreline of the island and
prominent landmarks on each map, such as school, church
and town hall. The means of discerning wetlands from uplands
we used in this study was a combination of wetland/upland
indicators. Wetland indicators include marsh vegetation and
dead upland vegetation and in black/white imagery, dark land
coloration. Upland indicators include trees and lawn grass and/or
lighter coloration in black and white images. Site visits were
conducted to confirm the presence of wetlands and uplands
as estimated via image interpretation at a haphazardly selected
number of sites within the Town (see a subset of these
photos at Supplementary Photos 16). The rate of upland to
wetland conversion of each ridge was calculated. Additionally,
the mean rate of conversion of all ridges was calculated to
model a regression that was compared to the regression of the
population data.
The ridge that will endure the longest was used to
project the year in which Tangier Island will have no
upland left and the Town abandoned. Data analysis was done
through Microsoft Excel and the statistical analysis program,
SigmaPlot. Then, we conducted an analysis of the Sewell’s
Point, located 95 km South of Tangier in Virginia waters
of southern Chesapeake Bay (see Supplementary Figure 13),
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Wu and Schulte Climate Change-Driven Tangier Exodus
tide gauge’s raw data (1967–2020) with the sea-level rise
curves predicted from the USACE’s sea level change curve
calculator (US Army Corps of Engineers, 2021)1to determine
the relationship of the raw Sewell’s Point’s RSLR data to the
three USACE’s sea-level rise curve scenarios (low, mid or
high) in order to determine how the raw data of local RSLR
is trending.
Finally, we also estimated the cost of and conceptualized a plan
to relocate and one to rescue Tangier Island, the Town and its
inhabitants. Estimates were developed referencing similar efforts
by the US Federal government in saving similar small coastal
communities from sea-level rise.
RESULTS
The extent of the Town of Tangier’s uplands converted
into wetlands due to sea level rise has been extreme since
1967, especially that of the West Ridge (Figure 2). Overall,
the Town’s uplands have lost 61.88% of its original 1967
upland area. The West Ridge has lost (71.81%), Main
Ridge (56.64%) and Canton Ridge (61.23%) from 1967–
2019 due to upland to wetland conversion (Figures 2,
4). The majority of individual properties in the Town
now hold some wetlands. Some properties have been
converted almost entirely to wetlands, in such cases the
home and any support structures (storage sheds, walkways,
parking platforms) on the property have been raised (see
Supplementary Photos).
We fit regressions to the data of the three ridges to predict
the upland lifespan of the Town of Tangier’s three ridges.
The best fits (highest r2, all parameters had p<0.05) were
quadratic for West and Main Ridge and linear for Canton
Ridge. The regressions for each ridge, respectively, predicted that
if upland to wetland conversion and RSLR were to continue
as predicted, the year of full conversion to wetlands is: 2051
(Canton Ridge), 2035 (Main Ridge) and 2033 (West Ridge),
(Figure 4). Canton Ridge, despite being the smallest in area
of the three, holds the largest extent of land higher than
1 m above mean high water (MHW) and the only uplands
outside the airport 1.2 meters or higher (peak height is 1.5 m
MHW). Our analysis of the Sewell’s Point tidal gauge raw
data suggests that the RSLR of the Chesapeake Bay area
is as of now between the USACE’s high and middle RSLR
curve, trending toward the high curve if RSLR continues to
accelerate (Figure 5).
From our analysis of the Town population, we predict that
the Town will reach a population of 0 by the year 2053,
tracking quite similarly with the overall wetland conversion rate
of the three ridges’ uplands combined curve (Figure 6). This
result is consistent with our prediction with the full conversion
of the last Town uplands by 2051 (Figure 4). To confirm
our findings of the current upland extent, we compared our
findings (Figure 2) to the results of a recent light detection
and ranging (LIDAR) survey done over the southern portion
of Tangier Island that includes the Town (Figure 7) and noted
1https://cwbi-app.sec.usace.army.mil/rccslc/slcc_calc.html
that our estimation of upland location was confirmed by the
LIDAR survey, though it must be noted that the transition
from wetlands to upland does not occur precisely at the 2-foot
(0.6096 m) contour.
DISCUSSION
Our analysis confirms that the Town of Tangier has already been
severely impacted by climate-change-induced SLR. The West
Ridge is converting the fastest, however, the curve of the Main
ridge appears to be more aggressive compared to the West Ridge.
Canton, which our analysis shows will last the longest due to its
possession of the highest ground on the Island, was also the first
ridge to be settled by European colonists, likely due to its higher
elevation, which provides more protection against hurricane-
induced flooding. Main and West Ridge were initially where
much of the early farming occurred (Hall, 1939). We reason that
the much larger upland area of the Middle ridge has allowed for it
to endure its more aggressive conversion rate. The southernmost
tip of West Ridge converted from uplands to wetlands between
1970 and 1982 (Historic Aerials, 2021), resulting in the loss of
several homes. It was further impacted by coastal erosion and
continuing RSLR and is now underwater. Erosion is not a factor
due to the inshore position of the three upland ridges except
for this small area (Figure 2). This area was located south of
the shoreline revetment built to protect the airport and is the
shoreline of Tangier Island that experiences the highest rate of
land loss (Schulte et al., 2015), so this is not surprising. It provides
a modern-day prelude of the fate of the rest of the Town. The
conversion of all three ridges lies within the Schulte et al. (2015)
estimate of the Islands habitability and provides an alarming
timeline for the Town of Tangier, not just the Island as a whole.
Even if stones were placed surrounding the Island, halting coastal
erosion, this abandonment due to sea-level rise would still occur.
Stones alone will not be able to halt the rising water seeping up
through the sandy uplands of the Town. Due to this, the Town
of Tangier will have to be relocated earlier than estimations based
on inundation.
The data and analysis suggest there is also a significant
relationship between the decline in habitable uplands and
the number of citizens of the Town of Tangier, despite the
majority of the citizen’s steadfast refusal to accept climate change
as real. Based on the regression of the rate of population
decline (Figure 6), by 2053 the people of the Town of Tangier
will complete their exodus. While it is likely that a host of
factors drive this decline, such as difficulties in young people
obtaining commercial fishing licenses and associated gear, lack
of employment on the island, and the internet, which ended the
Town’s isolation, some of these have a link to sea-level rise as,
for example, there are no open uplands that could be developed
for new commercial or residential use. There is also a sense of
frustration, futility and abandonment for the state and Federal
governments by the Islanders, which also encourages Islanders
to move off the Island. There is good reason the Islanders hold
such feelings. For example, the stone revetment that was built
in 1989 using funds from Tangier Islanders, state and Federal
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Wu and Schulte Climate Change-Driven Tangier Exodus
governments to protect the Tangier Airport was requested by
the Tangier Islanders decades before, around 1960 (Yarrington,
2020). The only new business of consequence in recent years is a
nearshore oyster aquaculture operation. Older adults, who have
seen the decline in extent and quality of the lands of the Town
of Tangier, also tend to encourage their children to leave the
Island. Many young people do so and as a result, the remaining
population of the Town of Tangier is also aging (Swift, 2018).
These social issues should be addressed if a large-scale
intervention to restore the Town is undertaken. For example, aid
in obtaining a commercial fishing license and associated fishing
gear for young people who wish to follow the path of their
ancestors and become watermen, efforts to increase tourism, and
expansion of aquaculture in Tangier’s nearshore waters, could
be considered.
The data also supports our fourth hypothesis and rejects
the alternative, that the Town of Tangier and the Island “has
hundreds of years more (Gray, 2017).” They have but a few short
decades. It is also possible that the final exodus of the Town’s
citizens could occur earlier than final conversion of all uplands.
Once infrastructure such as the Churches, grocery store, school
and others become too difficult to maintain, due to flood-related
expenses, impacts and lack of dry land, or there becomes too
few people to support their maintenance, these facilities will have
to close. This would accelerate the exodus of the last Tangier
Islanders from their home.
As noted, additional actions beyond placing stones at
vulnerable points of the Island’s perimeter will be needed if the
Town of Tangier is to be saved from rising waters. The Town
will need to be raised, or it will soon need to be abandoned. The
Schulte et al. (2015) study proposed an interim plan to buy the
island some time, mainly by supplying sediment to the western
shore of the island and protecting the most vulnerable shorelines
with additional stone at an estimated cost of 30–50 million USD.
This approach did not assess the long-term costs associated with
saving the Town, which needs to be elevated to remain habitable
as sea level rises. We will estimate these costs, as well as estimate
the cost of relocating the Town of Tangier and its people. The
Town has a complete infrastructure, including utilities, roads,
fuel storage, commercial fishing facilities, homes, churches,
cemeteries and educational, recreational, and tourism-related
infrastructure. Regarding abandonment of the Town and exodus
of its people, all of this will need to be either decommissioned and
removed (utilities) to possibly be relocated physically (homes,
churches, cemeteries, the school) or simply abandoned (homes,
cemeteries, and structures with non-toxic materials). Physically
relocating over 400 people, all their homes and belongings, and
decommissioning the Town will be an expensive undertaking.
Several USA Federal government estimates of costs (US Army
Corps of Engineers, 2004; US Government Accountability Office,
(GAO), 2009) to relocate for small coastal towns in similar,
dire climate-change driven situations include: the Towns of
Shishmaref (pop. 563), (100–200 million USD), Newtok (pop.
354), (80–130 million USD), and Kivalina, AK (pop. 374), (95–
125 million USD); the Quinault Nation (pop. 600), (60–100
million USD) in WA, and Isle de Jean Charles (pop. 99), (48
million USD), LA. Due to the size of the Town of Tangier, its
extensive infrastructure, and its offshore island nature, relocating
the Town will likely be on the higher end of these estimates, from
100 to 200 million USD.
What about saving the Town? We estimate it would cost
roughly 250–350 million USD to fully protect and restore the
Town of Tangier and Tangier Island. Primary, necessary actions
included in this estimate are applying protective stone along
all vulnerable shorelines of the Island (a significant portion of
the shoreline would not need such protection), raising the 35
ha of the three ridges by 3 m using sand dredged from the
bottom of Chesapeake Bay, retrofits of plumbing and electrical
throughout the Town, and raising the system of one-lane roads
for transportation.
Recommended secondary actions to further aid Tangier Island
and increase longevity would include the use of Natural and
Nature-Based Features (NNBF), which can be effectively used
to enhance local ecosystems and nearby built infrastructure’s
resilience against SLR (Narayan et al., 2016; Whitfield et al.,
2020). Estimated costs were developed for NNBF restoration at
Tangier Island, based on current literature (Bridges et al., 2015;
Aerts, 2018). All NNBF considered either are present, though
significantly reduced in extent compared to historical conditions,
or were once present but are currently extirpated. While these
NNBF are not the primary means to save the Town, they will
assist in improving the long-term stability of the Island and Town
and greatly increase their ecological value. There are still remnant
dunes south of the West Ridge and in a few other areas, including
the uninhabited Uppards. At initial European settlement, the
Island still held extensive forested areas, though today these are
entirely extirpated except for a small area on the easternmost
sub-islet of Tangier, which was actively restored by placement
of dredged material to elevate the land, then planted with trees.
Oyster reefs are still common, especially subtidal. Intertidal reefs
were exploited by Native Americans pre-European colonization
as well as by early European settlers as evidenced by shell middens
scattered over the Island (Yarrington, 2020). We recommend
thin spray dredging, an application of a 10–15 cm thick layer of
material on top of existing wetlands to slow inundation by raising
the elevation of the wetland and enhance vegetative growth
(Ford et al., 1999; Ray, 2007; VanZomeren and Piercy, 2019) at
an estimated cost of 5–10,000 USD/ha. Restoring several areas
of former uplands on abandoned lands North of the Town as
dunes at an estimated cost of 15–30,000 USD/ha, then creating
maritime forested uplands behind them on newly elevated land
behind the dunes at the cost of 15–50,000 USD/ha would help
protect the Town from severe winter storms coming from a
more northern direction, known as a Nor’easter in the USA.
A final recommended action for Tangier Island and the Town
is to construct nearshore, low-intertidal, high-relief oyster reefs
at an estimated cost of 100,000–300,000 USD/ha, depending on
materials used and height of the restored reef to help protect the
unarmored shorelines from wave energy and associated coastal
erosion (Wilberg et al., 2019) on the east side of the Island.
These costs, whether to save or abandon the Town and Island
of Tangier are substantial, but it can and has been done before.
For example, in Maryland, Poplar Island, whose area reduced to 5
acres by 1993 by a combination of erosion and RSLR, is currently
Frontiers in Climate | www.frontiersin.org 7November 2021 | Volume 3 | Article 779774
Wu and Schulte Climate Change-Driven Tangier Exodus
being restored to its 1,840 footprint of 1,715 acres at a cost of
1.4 billion USD. This Island, similar to Tangier, was also settled
by European colonists and was permanently settled. The Town
on Poplar Island was known as Valliant, which persisted until the
1920s when it was abandoned due to rising waters and erosion-
driven loss of land. The restoration effort for Poplar Island is not
intended to make the island habitable, but for wildlife habitat
enhancement. This undertaking is driven by the need to maintain
the depth of the main shipping channel leading to Baltimore
Harbor, Maryland. This restoration effort is the least expensive
means to dispose of locally dredged material by disposing of
dredged materials at the Poplar Island site (USACE, 2021). That
Poplar Island is being restored as a wildlife habitat, and is not
intended for permanent human settlement, while the continuing
decline of Tangier Island and its Town proceeds is a source of
much consternation in the Town populace (Gertner, 2016; Swift,
2018; Yarrington, 2020). The issue here is simple economics:
there is a need to cheaply dispose of dredged material near Poplar
Island, which has stimulated its restoration efforts. Unfortunately
for Tangier, there is no such need, a fact which may seal the fate
of the Town of Tangier.
Lastly, this study suggests that the current sea level rise
trend in the Chesapeake Bay has been recently trending toward
the USACE’s high curve (Figure 5) in agreement with recent
acceleration in global mean SLR (IPCC, 2021). This is an
alarming trend that, unless bold, collective, worldwide human
intervention to slow carbon emissions becomes a priority for
humanity, will continue to accelerate. Our study also suggests
that coastal protection infrastructure built in the near future
will likely need to consider and prioritize means to counter
the higher-range SLR scenarios for their region, rather than
using a low or mid-range scenarios, which appear increasingly
optimistic. The latest IPCC report (2021) predicts we have
only a short time (10–15 years) left to significantly reduce
carbon emissions worldwide to avoid the worst-case scenario
of exceeding 1.5C. Our study supports these grim findings
and suggests that the Town of Tangier is in its end times.
Abandonment of the Town and exodus of its people will almost
certainly occur in within a few decades due to accelerating sea-
level rise without significant human intervention. The Town of
Tangier’s citizens will join the growing numbers of humanity
forced to relocate due to climate change, becoming climate
change refugees. That this is happening such a short distance
away (150 km) from the Capital of the USA in Washington
DC and proceeding apace with little aid despite all the media
attention Tangier Island and the Town have had should alarm
us all.
If the Town and Island of Tangier are saved via human
intervention or abandoned to rising waters and its people
relocated to the mainland is beyond the scope of the present
study, but it is a choice that will soon need to be made by
policymakers. The choices they make will soon define how
our fellow Americans in the USA most vulnerable to climate
change, which are often Native American, minority, or low-
income such as the isolated fishing community of Tangier, will
have their needs addressed—or ignored. The same holds true
for many coastal communities throughout the world (Loughry
and McAdam, 2008). Ultimately, the actions we take (or don’t
take) collectively will determine how many more towns and
cities will end up like the Town of Tangier in coming decades.
As a local example: In Chesapeake Bay, Holland Island, once
a thriving community of 360, is now a sand bar covered by
high tide. Abandoned in 1922 due to land losses caused by
erosion and RSLR, desperate attempts were made to preserve
the last of its lands for decades. These lands after 1922 were
mostly a seabird rookery but included several graveyards and
the last house standing. By 2010, this last home succumbed to
the rising waters of the Bay, by 2012 the graveyards and rookery
(Foley and Rue, 2015; White, 2015). A similar loss of graveyards
recently occurred at the formerly inhabited ridge of Tangier
Island, Canaan, abandoned in the 1930s due to its isolation,
erosion and RSLR, the bones of the formerly buried now scattered
over the shore (Mayfield, 2017; Swift, 2018). Soon, the rest of the
Town of Tangier will be uninhabitable due to sea level rise. The
question we pose for policymakers is: “What will it take for you
to act?”
DATA AVAILABILITY STATEMENT
The raw data supporting the conclusions of this article will be
made available by the authors, without undue reservation.
AUTHOR CONTRIBUTIONS
ZW and DS contributed to study conception and design. ZW
collected the island imagery and related data. DS collected
the data related to sea level rise and performed statistical
analysis on local sea level rise and population decline. ZW
performed the statistical analysis on upland conversion, wrote
the first draft of the manuscript, except for the sea level
rise and section on costs of Town/Island abandonment, and
conceptual restoration plan which was written by DS. Both
authors contributed to manuscript revision, read and approved
the submitted version.
SUPPLEMENTARY MATERIAL
The Supplementary Material for this article can be found
online at: https://www.frontiersin.org/articles/10.3389/fclim.
2021.779774/full#supplementary-material
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Conflict of Interest: ZW and DS are employed by Biogenic Solutions
Consulting, LLC.
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Copyright © 2021 Wu and Schulte. This is an open-access article distributed
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Frontiers in Climate | www.frontiersin.org 9November 2021 | Volume 3 | Article 779774
... Scientists predict that Tangier will soon need to be abandoned; full "wetland conversion" is predicted by 2051, putting predictions of the island's necessary abandonment at the 2040s. Scientists at the U.S. Army Corps of Engineers division in Norfolk suggest multiple causes for Tangier's subsidence, including anthropogenic sea-level rise, groundwater pumping on mainland Virginia, and effects from a meteor strike 35.5 million years ago at the mouth of the bay (Schulte et al., 2015;Wu & Schulte, 2021;cf. Mills et al., 2005). ...
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