UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN - 2020 Report
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UNDERSTANDING CLIMATE 2020 Report
CHANGE IN SAINT JOHN
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 1
2020 Report
PUBLISHED BY:
-
ATLANTIC COASTAL ACTION
PROGRAM [ACAP] SAINT JOHN INC.
139 PRINCE EDWARD STREET, SUITE 323
SAINT JOHN, NEW BRUNSWICK
CANADA
E2L - 3S3
TEL: (506) 652-2227
FAX: (506) 801-3810
E-MAIL: OFFICE@ACAPSJ.ORG
WEB: WWW.ACAPSJ.ORG
Reproduction of this report in part or
in full requires written permission from
Atlantic Coastal Action Program [ACAP]
Saint John Inc.
2
PUBLISHED
BY: INTRODUCTION
Climate Change is one of the greatest challenges facing also discussed. Understanding how Climate Change will
human civilization today. It directly affects fundamental affect the community is critical for developing effective
needs like food, water, and shelter. In Canada, the strategies and reducing negative outcomes.
rate of warming is nearly twice the global average and As a coastal city, sea level rise is of great concern for
impacts are already being felt. This report is intended to Saint John. Predictions suggest that a Higher High Water
be a resource for residents, businesses, developers and Large Tide (HHWLT) can be expected to be 6.2 m by 2100
Council members who are eager to learn more about the for a 100 year return period. Sea level rise projection data
changing environment in Saint John, New Brunswick, for various flooding scenarios are provided in this report
Canada. and social and environmental impacts are discussed.
The primary challenges posed to Saint John as a The largest challenge for areas impacted by sea level
result of Climate Change include increasing temperature, rise is the high economic cost associated with damage,
sea level rise, and higher intensity precipitation events. relocation, or long-term monitoring. Strong partnerships
These result in severe inland and coastal flooding, between multiple stakeholders will be required to protect
accelerated rates of coastal erosion, and loss of land. This public and industrial spaces against rising sea level.
report introduces Climate Change science and describes Climate Change compounds reoccurring challenges
the predicted weather changes for Saint John. These experienced in Saint John around water: changes in
changes include warmer annual temperatures, warmer seasonal riverine flooding, overflow from precipitation
winters, increases in rainfall events, rising sea levels, and events, and sea level rise. This report discusses challenges
changes to storm frequency and intensity. around freshwater availability and quality. Supporting
Inland flooding, a historical climate-related challenge healthy communities requires actions to ensure a safe
for Saint John, is discussed as the result of changing water supply is available.
seasonal temperature and precipitation patterns. The City of Saint John must develop adaptation
The benefits of green infrastructure or low impact strategies to reduce the negative impacts associated with
development strategies are investigated as a solution Climate Change. In Spring 2020, ACAP Saint John will
to reduce the risk of property damage from flooding. release the Climate Change Adaptation Plan for Saint
The impacts of extreme weather events, including post- John, which will provide recommendations to reduce
tropical storms, ice storms, and wildfires in Saint John are risks and increase the resilience of the community.
TABLE OF CONTENTS
1..................................................................................................................................................................Table of Contents
2.................................................................................................................................................................................Glossary
3...................................................................................................................................................................List of Acronyms
5..............................................................................................................................................Climate Change in Saint John
9..........................................................................................................................................................................Temperature
13........................................................................................................................................................................Precipitation
15.................................................................................................................................................................Extreme Weather
19.............................................................................................................................................................Sea Level Rise (SLR)
25...............................................................................................................................................................................Flooding
29.....................................................................................................................................Urban Water Quality and Security
32...........................................................................................................................................................................Next Steps
33...........................................................................................................................................................................References
35............................................................................................................................................APPENDIX A: CLIMATE DATA
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 1
GLOSSARY
Adaptation Coastal Squeeze to have a GWP of 1 over predicted water levels over
Initiatives and measures A form of coastal habitat a 100-year time period, a 19 year period.
that reduce the loss, where intertidal methane is estimated to
vulnerability of human and habitats such as salt have a GWP of 28-36 over
natural systems to actual marshes, mudflats or 100 years and nitrous oxide Inland Flooding
or anticipated Climate sand dunes are lost or is estimated to have a Flooding experienced
Change effects. deteriorated due to high GWP of 298 (United States as a result of heavy
water levels. In response Environmental Protection precipitation events or
to sea level rise, defence Agency, 2017). high river flows occurring
Aquifer structures (i.e. a sea wall) in natural and built
A subsurface layer of can prevent the inward environments.
rock that holds water. The migration of land. Greenhouse Gas (GHG)
pores and cracks in the Compounds that can
rock allow water to be absorb infrared radiation Low Impact Development
stored until it is pumped to Ecosystem and trap heat in the (LID)
the surface for use. A system of living atmosphere, contributing Urban infrastructure
organisms interacting to The Greenhouse Effect. installed with an emphasis
with each other and their on conservation of
Blue Infrastructure physical environment natural features with
Landscape elements linked ranging from very small Green Infrastructure the intention to reduce
to water bodies, such as spatial scales to entire Development that utilizes urban challenges around
pools, ponds, artificial regions, i.e. coastlines and and promotes the benefits stormwater management.
buffer basins or water watersheds. of ecosystem services
courses. including stormwater
management, water Mitigation
Flood filtration, carbon storage, Any policy, regulation, or
Climate A significant rise of water enhanced biodiversity, and project-based measure
The average weather level in a stream, lake, community well-being. that contributes to the
measured by the reservoir or a coastal stabilization or reduction
statistical description region from excessive of greenhouse gas
of mean variability of rain, severe storms, rapid Grey Infrastructure concentrations including
wind, precipitation, snow or ice melt, blocked Engineering and building renewable energy
temperatures etc. over watercourses, failure of projects that are made programs, and energy
time ranging from months dams, land subsidence from concrete and/or efficiency plans.
to thousands or millions of or storm surges that steel and are typically
years. inundates natural or built impervious in urban
landscapes within city settings. Resilience
boundaries. The capacity of a system,
Climate Change community or society
The long-term changes in Harmful Algal Blooms exposed to hazards
climate variables, such as Flood Risk (HABs) to adapt, by resisting
precipitation, temperature, The combination of Occur when colonies of or changing in order
sea level, lake levels, and hazards and vulnerability algae grow to produce to reach and maintain
changes in the frequency to floods that have a high toxic or harmful effects an acceptable level of
and intensity of extreme probability to occur and/ on people, fish, shellfish, functioning and structure.
weather events. or have significant impact marine mammals, and
on property, health, or birds.
livelihoods. Saltwater-Freshwater
Coastal Erosion Interface
The process of removal Higher High Water Large The boundary beneath
and transport of soil and/ Global Warming Potential Tide (HHWLT) the Earth’s surface
or rock from shorelines as (GWP) A representation of the where saltwater and
a result of weathering by A ratio of how much heat storm surge impacts freshwater meet as a
streams, glaciers, waves, a gas traps in a specific associated with the moon gradual transition zone
or high winds. time frame relative to CO2 cycle on the high tide. It where water becomes
(IPCC, 2014). For instance, is determined by taking more saline as it moves
where CO2 is estimated the average of highest seawards.
2
Saltwater Intrusion or snowmelt that flows Vulnerability Watershed
The process of seawater across the landscape and The likelihood of a system An area delineated
infiltrating coastal is not stored or taken up suffering an adverse topographically were all
groundwater systems, by plants. This can be rain, impact of Climate Change precipitation drains to one
mixing with a local melting snow or ice that when exposed to extreme point or outlet.
freshwater supply. washes off hard surfaces. weather.
Urban Heat Island (UHI)
Storm Surge Stakeholders Water Security The warming effect of
A localized, temporary A party, including The capacity of a city built urban spaces on air
rise in water occurring residents, businesses, to protect urban water temperature in comparison
during specific weather developers, First Nations, quality and availability to to surrounding rural areas.
conditions. NGOs, academics, and sustain livelihoods, well-
City staff and Councillors being and socio-economic
Stormwater Runoff who have an interest in a development.
Water from precipitation specific issue.
LIST OF ACRONYMS
AR5..........................................................................................................................................IPCC Fifth Assessment Report
AR6......................................................................................................................................... IPCC Sixth Assessment Report
DFAA................................................................................................................. Disaster Financial Assistance Arrangements
ECCC...................................................................................................................Environment and Climate Change Canada
FTC......................................................................................................................................................... Freeze-Thaw Cycles
GCMs.......................................................................................................................................... General Circulation Models
GHG..............................................................................................................................................................Greenhouse Gas
GNB....................................................................................................................................... Government of New Brunswick
GWP............................................................................................................................................... Global Warming Potential
HABs.................................................................................................................................................... Harmful Algal Blooms
HHWLT................................................................................................................................... Higher High Water Large Tide
IPCC................................................................................................................. Intergovernmental Panel on Climate Change
LID.................................................................................................................................................. Low Impact Development
NBDELG...................................................................... New Brunswick Department of Environment and Local Government
NB EMO................................................................................................ New Brunswick Emergency Measures Organization
RCP...........................................................................................................................Representative Concentration Pathway
UHI..............................................................................................................................................................Urban Heat Island
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 3
4
1. CLIMATE CHANGE IN SAINT JOHN
Climate Change has by The Greenhouse
become a regular focus Effect, which acts to
of media across the world regulate temperature What is the difference between
and more so than ever by trapping greenhouse adaptation & mitigation?
there is positive action gases (Figure 1). This
being taken by local natural process controls
communities, nations, the Earth’s temperature Adaptation:
and municipalities to and has allowed for Process of adjustment to actual or expected climate
prepare and adapt to ecosystems to develop and its effects. In human systems, adaptation seeks
changing conditions. The and diversify. GHG to moderate harm or exploit beneficial opportunities.
City of Saint John has emissions come from In natural systems, human intervention may facilitate
an opportunity to adapt both natural and man- adjustment to expected climate and its effects.
to the changing climate made sources and include
and continue to develop carbon dioxide (CO2), Mitigation:
as a thriving community. methane, water vapour, Human intervention to reduce the sources or enhance
This chapter is intended nitrous oxides, ozone, the sinks of GHGs. (IPCC, n.d.)
to introduce Climate hydrofluorocarbons,
Change science including perfluorocarbons and
greenhouse gases sulphur hexafluoride.
(GHGs), climate modelling Each of these gases has
terminology and the a specific capacity for
changes projected for warming the atmosphere
Saint John. called the global warming
potential (IPCC, 2001).
CO₂ and other gases
While CO2 is often the
in the atmosphere
1.1 Introduction to focus of Climate Change trap heat, keeping the
Climate Change conversations, each earth warm.
Science of these gases play a
significant role in The
The Intergovernmental Greenhouse Effect. Some sunlight that
In the atmosphere, hits the earth is
Panel on Climate Change
GHGs can be transformed reflected.
(IPCC), established in Some become heat.
1988, is a United Nations by chemical processes
scientific body and and released beyond
the foremost authority the atmosphere, but
on Climate Change most are trapped, left to
science. In 2014, the Fifth absorb incoming solar
Scientific Assessment energy and keep the
Report (AR5) was planet’s surface warm.
released emphasizing the The dramatic increase
severity of our warming in GHG emissions by
climate system. The humans, or anthropogenic
Sixth Assessment Report sources, has enhanced
(AR6), scheduled to be The Greenhouse Effect,
released in 2021, will trapping heat in the
provide stakeholders with atmosphere and resulting
modern solutions and in warmer temperatures
updates about successful that alter atmospheric
strategies to reduce and hydrologic processes.
Climate Change impacts. Higher concentrations
of GHGs in the
atmosphere have led to
1.1.1 The Greenhouse 2016 being the world’s
hottest year on record
Effect
(World Meteorological
Organization, 2020). This Figure 1: The Greenhouse Effect, where the sun’s heat is trapped in
The global climate the atmosphere by higher quantities of greenhouse gas emissions
aligns with a trend in
system is maintained (Mathematics of Planet Earth, 2012).
global warming that has
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 5
been observed over the 2001). For this report,
last 60 years confirming the climate data was
athat our climate is generated using outputs Weather is defined as the fluctuating
changing with abnormal from 24 climate models state of the atmosphere characterized
rapidity (Figure 2). by national weather by temperature, wind, precipitation, and
services and research clouds, and can only predictable over hours,
organizations from days, or weeks. Climate is the average
1.1.2 Climate Modelling nine countries (Roy and variability of these elements (or weather)
Huard, 2016). To generate over time. Climate can be observed over
The components and realistic projections, different scales, ranging from months to
interactions of the an emission scenario is thousands or millions of years.
climate system can be applied during climate
studied and simulated modelling to represent the
using climate models. concentration of GHGs
The General Circulation that will be involved in
Model (GCM) is the the system. The data in
starting point for scientists this report is based on the
who will use numerous highest emission scenario
models to generate (RCP 8.5), which is closest
accurate data (IPCC, to current trends.
NASA Goddard Institute NOAA National Center for
for Space Studies Environmental Information
Temperature Anomaly (ºC) Hadley Center/Climatic Japanese Meteorological
Research Unit Agency
Figure 2: Temperature trends from 1880-2020 (National
Aeronautics Space Agency, 2017).
6
What is
a Baseline?
To generate future
climate, a baseline
of historical
data is required.
Reports will refer
to this baseline
when discussing
the anticipated
changes. For
example: 1.5
degrees Celsius of
warming compared
to 2005 levels,
where 2005 levels
represent the
historical data. The
baseline period
should be the same
length of time as
the projected term
and is most often a
30 year period.
1.2 Conclusion
Chapter One has provided
a brief overview of Climate
Change science and
modelling. The subsequent
chapters will describe the
climate projections for
Saint John and discuss the
associated impacts.
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 7
8
2. TEMPERATURE
The average annual temperature in New Brunswick, 2071-2100 (Figure 4 A & B). Average winter temperatures
relative to 1990 levels has increased by 1.1°C over the will increase from -5.4°C up to -1°C by 2071-2100 resulting
last 30 years (NBDELG, 2018a). Compared to the same in more freeze-thaw days (Figure 4 C & D). The projection
1990 baseline, annual temperatures in the province are data shows the annual number of freeze-thaw days
expected to increase 3.5°C by 2080 (Roy and Huard, will peak mid-century (2011-2040) and then decline as
2016). In the Greater Saint John Area, hotter summers mean winter temperatures approach zero in the late
and shorter, warmer winters can be expected in the century (Roy and Huard, 2016). Winter temperatures
future decades. Temperature projections are displayed in hovering around zero degrees can be dangerous due to
Figures 3 and 4 and climate data is available in Appendix the threat of freezing-rain events which are challenging
A (Table 1). The annual temperature in the Greater Saint to predict. Weather alerts provided by Environment and
John Area is expected to rise from 5.7°C up to 9.1°C by Climate Change Canada (ECCC) are critical for ensuring
2071-2100 (Figure 3). Mean summer temperature could communities are prepared and safe during periods of
rise 3.4°C by 2071-2100 with an increase in the number of unpredictable weather conditions.
hot days (above 25°C) from 9.5 in 1971-2005 to 70 days in
Average Annual Temperature
Change For Saint John
Figure 3: Average annual temperature change for Saint John up to the year 2100 by the Atlantic Climate Adaptation Solutions
Association (ACASA) New Brunswick Climate Futures Projections (Roy and Huard, 2016).
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 9Temperature Changes For Saint John Up To The Year 2100 10
Figure 4: Temperature changes for Saint John up to the year 2100. (A) Average summer temperature projections. (B) The number
of hot days where temperatures exceed 25°C. (C) Average winter temperature projections. (D) The number of freeze-thaw days
where temperatures hover around zero degrees.
Did you know?
Freeze-thaw days occur when the daily maximum temperature is greater than 0°Cand the daily
minimum temperature is less than 0°C. These freeze-thaw cycles (FTCs) are associated with ice
and slush conditions which can directly result in damage to built infrastructure. Indirect impacts are
challenging to predict and include increased use of road salt and changes to ecological cycles. FTCs are
significant for plants or animal species that require stable temperatures for dormancy or are sensitive
to cold spells. The production of maple syrup is an example of an industry that relies on FTCs and will
need to adapt to these changing climate conditions (Roy and Huard, 2016).
In urban spaces, concrete infrastructure and dark experiencing dangerous extreme heat events. In Saint
surfaces absorb heat resulting in higher air temperatures John, the UHI effect is moderated by the coastal setting.
when compared to the surrounding rural areas. In climate As temperatures increase, monitoring and education
science, this is known as the Urban Heat Island (UHI) around heat related illness will be necessary to avoid
effect (Figure 5). Residential and commercial heating and hazards associated with heat and the UHI effect.
cooling systems, vehicles and other appliances generate As the average annual temperature increases,
heat and contribute to the UHI. In combination with Saint John will experience earlier snowmelt, mid-winter
increasing annual temperatures, many large cities are thaws, and ice breakups which can lead to significant
The Urban Heat Island Effect
Figure 5: The Urban Heat Island effect: heat is absorbed and
held by concrete and asphalt in cities. Tall buildings and lack of
vegetation prevent heat from dissipating and diminish natural
shade and evaporative cooling (Warren and Lemmen, 2004).
infrastructure damage when combined with intense Brunswick communities are beginning to adjust to the
rainfall (NBDELG, 2014). In 2018 and 2019, Saint John impacts of warmer temperatures, however education and
experienced extensive inland flooding due to the awareness about adaptation will be needed to reduce the
combination of spring freshet and extreme rainfall. New health risks of warmer temperatures in Saint John.
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 1112
3. PRECIPITATION
Precipitation trends tend to vary more than temperature, 6; NBDELG, 2018a, Roy & Huard, 2016). This means that
making patterns of rainfall in the Greater Saint John area more precipitation will be falling during shorter periods,
difficult to predict. Climate models project that New increasing the amount of stormwater that will be running
Brunswick will experience an extension of dry periods through sewer infrastructure and into nearby waterways.
and an increase in heavy precipitation events resulting The type of seasonal precipitation (rain, snow, sleet,
in a net increase in mean annual precipitation (Figure hail, etc.) in the Greater Saint John area is expected to
Projected changes to precipitation
in Saint John
change. As temperatures rise, the annual number of
snow days will decrease which correlates to an increase Figure 6: Projected changes to precipitation in Saint John.
in rain days and may result in more flooding than An increase in annual precipitation is anticipated (A) and
historically observed (Roy and Huard, 2016). River flows changes in the annual number of rain days and snow days
will become more variable as spring peak flow will occur are shown (B) and (C). Precipitation projections up to the
earlier and summer minimal flows will be lower. During year 2100 by the Atlantic Climate Adaptation Solutions
summer months, rivers may experience an increase in Association (ACASA) New Brunswick Climate Futures
periods of very low or zero flow that can have significant Projections (Roy and Huard, 2016).
ecological impact (NBDELG, n.d.). Climate data is
available in Appendix A (Table 2).
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 1314
4. EXTREME WEATHER
Extreme weather events are controlled by changes in communities. Most notable were damages in 2008, 2018,
atmospheric temperature, pressure and moisture. They and 2019 when heavy rain events coincided with the
are expected to become more frequent and intense melting of record-breaking snowfall (NBDELG, n.d.).
as a result of changing climate. For every 1°C rise in Projection trends show an increase in the annual
temperature the amount of moisture in the atmosphere temperature and precipitation in Saint John, however
increases by 7% or more (Daigle, 2012). In response to emphasis must be placed on the extremes of each
increased moisture, New Brunswick can expect 10 to 20% variable, for example days of extreme heat or heavy
more extreme rainfall events per year (Canadian Center precipitation events. The impacts of extreme wind,
for Climate Modeling and Analysis, 2017). Historically, including power outages and fallen trees are already
extreme rainfall events (50 millimetres or more over experienced throughout the City. Preparedness is
a 24-hour period) have caused millions of dollars in essential to avoid injury and respond quickly as extreme
flood damage in Saint John, as well as within outlying wind events will continue to be experienced.
Natural disasters recorded in Figure 7: Natural disasters recorded in Atlantic Canada from
1900-2005, retrieved from Atlantic Climate Adaptation Solutions
Atlantic Canada from 1900-2005 Association (2011).
From 1900-2005, Atlantic Canada experienced In 2017, a survey was conducted by the Conservation
approximately 53 flooding events, 16 hurricanes, and Council of New Brunswick after post-tropical storm
13 winter storms (Figure 7). With shifting hydrological Arthur, which hit the Maritimes in July 2014. The
conditions and warming temperatures, Saint John responses highlighted gaps in emergency preparedness
can expect an increase in the intensity and frequency that should be addressed in all New Brunswick
of heavy precipitation, high winds, storm surges, municipalities (Comeau, 2017). The biggest concerns
summer convective storms (thunderstorms, hail storms, for the citizens who participated were power loss, food,
hurricanes), and severe winter storms. These events water, downed trees, and blocked roads. Municipal
are often associated with high damage and recovery staffing and a lack of qualified contractors to conduct
costs, emphasizing the importance of preparedness and cleanup was also recognized as a significant issue.
adaptation. Learning from past extreme weather events
can provide insights necessary to lessen future impacts.
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 154.1 Frequency and Despite a general trend trend in more severe compounded by higher sea
Economic Costs of increased frequency, weather events. Over six levels these events can lead
anticipating extreme years (2009-2015) the total to power outages, flooding,
Canadian municipalities weather events continues of DFAA costs associated and isolation which
have experienced significant to be a challenge. Unlike with extreme weather was can result in significant
increases in the costs overall temperature and greater than the previous economic and public
associated with property precipitation trends, 39 fiscal years combined. health risks (NBDELG,
damage and emergency windstorms, heavy In those years, flooding n.d.). During the winter, ice
response caused by precipitation, heat waves, accounted for 75% of all storms create hazardous
more frequent extreme forest fires, drought, expenditures (Moudrak conditions for citizens
weather events (Moudrak and ice storms are not and Feltmate, 2017). travelling throughout
and Feltmate, 2017). accurately represented the City. As the winter
Public Safety Canada has through climate models, temperature increases
found that the number especially on a regional 4.2 Post-tropical closer to zero degrees
of incidences where scale (Université Virtuelle Storms, Hurricanes and Celcius more freezing rain
provinces and territories Environnement et Ice Storms and ice accumulation is
have required or obtained Développement Durable, anticipated.
Disaster Financial Assistance 2016). Without an accurate The City of Saint John is
Arrangements (DFAA) model, the statistics from at risk to damages from Figure 8: Number of
significantly increased DFAA and the Insurance natural disasters in
post-tropical storms and
Bureau of Canada highlight Canada requiring DFAA
between 1970 and 2015, hurricanes which bring
the need for municipalities from 1970-2015
well in excess of population strong winds and heavy (Moudrak and Feltmate,
growth (Figure 8). to prepare for an increasing precipitation. When 2017).
Number of Tropical Storms,
Number of Hurricanes and Sum Number of Tropical
Storms
Number of Hurricanes Sum
Figure 9: Frequency of tropical storms and hurricanes in the North Atlantic region since 1850 displaying cyclic variations but an
overall increase (ACAP Saint John, 2016).
164.2.1 Tropical storms, 4.2.2 Ice Storms 4.3 Drought and Increased fire hazard
hurricanes and post- Wildfires in New Brunswick will
tropical storms As a result of increased threaten infrastructure and
temperature and Climate Change is ecosystems and reduce
A tropical storm describes precipitation, freezing expected to impact air quality. To adapt, the
a storm system with a rain, and ice storm events temperature and Government of New
low-pressure centre that will create new challenges precipitation extremes in Brunswick recommends
develops over tropical for municipalities. During the Greater Saint John maintaining air quality
or subtropical waters in January of 2017, a multi-day area. This means that tracking and advisory
the Atlantic Ocean. If ice storm along the coast warmer temperatures programs, increasing the
temperature conditions are of New Brunswick led to may be experienced in number of health studies
suitable, a tropical storm road closures, downed combination with periods to better understand the
can develop into a tropical trees and powerlines, of heavy precipitation or risks of forest fire smoke,
cyclone, commonly resulting in power outages with periods of minimal and to promote appropriate
known as a hurricane. A for over 300,000 residents. precipitation. These forest fire risk prevention
post-tropical describes Extended power outages changes will have severe or mitigation behavior on a
a storm that maintains from ice accumulation on impacts such as increased municipal level (NBDELG,
strong winds and heavy power lines and fallen trees drought stress on crops n.d.). In Saint John, similar
precipitation but does not are especially dangerous and shortages of drinking wildfire adaptation is
qualify as a tropical storm during cold temperatures. water (NBDELG, n.d.). The necessary for properties
as it no longer exists in Following this event, City of Saint John is at with large woodlots and
tropical regions. the Government of New low risk to these impacts park spaces.
This type of storm Brunswick developed a due to the availability
system develops when sea series of recommendations of drinking water from
surface temperatures are to reduce vulnerability surface reservoirs. 4.4 Conclusion
above 25°C (NOAA, 2019). during these types of
As a result of increases storms (GNB, 2017). As the frequency and
in both annual surface In Saint John, winter The IPCC defines severity of extreme
temperatures and sea temperatures will increase drought as a weather events increases,
surface temperatures, creating ideal conditions period of dry adaptation strategies must
more frequent and severe for freezing rain events weather that leads be taken to reduce negative
storms are predicted and ice storms. When to an abnormal impacts on municipalities.
around the world. Trends in combined with poor Results from the public
balance of water
the North Atlantic support visibility, low temperatures survey conducted by the
and high winds, the
in the system
this prediction showing Conservation Council of
presence of ice can be (IPCC, n.d).
an increase in the number New Brunswick provides
of tropical storms and extremely hazardous for several recommendations
hurricanes compared to residents (NOAA, n.d.-a). Drought conditions create for municipalities to reduce
historical events a(Figure Adaptation strategies dry and warm forested vulnerability to extreme
9). This trend emphasizes to reduce the hazards regions, providing fuel weather. Some adaptations
the need for adaptation associated with ice storms for wildfires to break out. include: cyclical tree
and preparedness in the include tree trimming Occurrence of wildfires trimming around power
Greater Saint John area. around power lines in Canada’s boreal forest lines to reduce potential
and education around is the highest observed in power outages; backup
emergency preparedness. human history, resulting power options with
in evacuations and stress the capacity to sustain
on remote communities residents for 3 to 7 days;
(WMO, 2019). Recent and training for emergency
studies suggest that the officials to handle mental
number of forest fires in health impacts that may
Canada will increase by require additional support
25% by 2030 and by 75 (Comeau, 2017). Exploring
to 140% by the end of the response and recovery from
century (Wotton, Nock, more recent storm events
& Flannigan, 2010). By the including post-tropical
year 2040, wildfires in storm Dorian (September
Canada may last an average 2019) can help identify
Figure 10: The conditions of 30 days and burn 1.5 where support is required
after an ice storm can times more forest area to build resilience to these
be extremely hazardous compared to the late 1990’s types of extreme weather.
for pedestrians and (Government of Canada,
motorists (Photo: ACAP 2018).
Saint John).
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 1718
5. SEA LEVEL RISE (SLR)
Global sea level is predicted
to rise by a maximum of
0.98 metres by 2100 (Daigle,
2012; IPCC, 2014). Between
1911 to 2000, sea level
increased by approximately
30 centimetres
(International Council
for Local Environmental
Initiatives Canada, n.d.).
Research suggests the
levels will continue to
rise by approximately
86 centimetres (+/- 38
centimetres) by the end of
the century (Daigle, 2014).
As a result, New Brunswick
will face more frequent and
permanent coastal flooding.
5.0.1 Why is the sea level
rising?
The rising sea level in Saint
John can be attributed to
a combination of melting
polar ice, warming ocean
temperatures and vertical
crustal movement. The
addition of freshwater
from melting ice caps
has a direct effect on sea
level. An increase in ocean
temperatures results in the
thermal expansion of water,
meaning water molecules
will take up more space
and contribute to rising
water levels. Lastly, the
geologic setting of Saint
John has a large role in
understanding sea level
rise. During the last ice-
age, the weight of glaciers
located over Quebec and
the St. Lawrence River put
pressure on Earth’s crust.
This resulted in crustal uplift
throughout Nova Scotia
and southeastern New
Brunswick (Koohzare et al.,
2007). When the pressure
of the ice was removed,
the crust began to subside Figure 11: The process of crustal subsidence being experienced in Saint John due to the pressure
to its original position. from glaciers during the most recent ice age (Henton et al, 2006).
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 19Saint John experiences return periods (Figure 12). 2017). Sea level rise data average. The cost of
a gradual subsidence Total sea level is the sum of can be found in Appendix A damages to homes in New
of approximately 0.4 Higher High Water Large (Table 3). Brunswick are expected
millimetres per year Tide (HHWLT), anticipated Sea level rise has to reach $730 to $1,830
(Daigle, 2014) (Figure 11). regional sea level rise, many impacts including per resident per year by
and highest storm surge coastal erosion, coastal the year 2050 (NBDELG,
amplitude. Using different squeeze, changing tidal 2014). To adapt to Climate
5.0.2 SLR Predictions return periods provides a amplitude, and increased Change, the City of Saint
for Saint John range of severity that can storm surge. Ultimately, John must take action to
be anticipated depending these can result in protect coastlines and
Flooding scenarios up to on the intensity of storm significant flooding events reduce the hazardous
the year 2100 have been events. The flooding and the permanent loss of impacts of sea level rise.
projected for coastal scenarios also include the land and habitat. The costs
communities in southeast glacial collapse of the West of coastal flooding are 100 Year
New Brunswick (Daigle, Antarctic ice sheet, which higher in New Brunswick 50 Year
2017). This research could result in further sea than any other Atlantic
level rise of approximately province and five times 5 Year
provides values for total
sea level over different 65 cm (Figure 12B; Daigle, higher than the Canadian 1 Year
Figure 12: (A) Flooding Scenarios for Saint John from 2010 to 2100, expressed as the total sea level for various return periods.
(B) Flooding scenarios include the collapse of the West Antarctic ice sheet which by the year 2100, would cause sea levels to
rise substantially more than projections suggest (Daigle, 2017). In both (A) and (B), an increase in sea level is observed.
20Return periods
express the
probability of a
flood or storm
event. For example,
a 1 in 100-year
event has a 1%
chance of occurring
in any given year;
a 1 in 5-year event
has a 20% chance
of occurring; and
a 1-year or annual
event is likely to
occur every year.
Return periods are
calculated based
on current weather
patterns and do not
include changes in
future climate. A 1
in 100-year event
could become a 1 in
50-year event as the
climate changes.
Figure 13: Shoreline erosion at Sand Cove Road in West Saint John (Photo: ACAP Saint John).
5.1 Coastal Erosion of an area. Red Head 14). Each strategy will increased risk of coastal
Road, Sand Cove Road, have different risks and erosion, flooding and
Sea level rise will not Bayshore Beach, Sheldon costs specific to the rate infrastructure damage
only lead to more severe Point Road and Lorneville of erosion. The expense (NBDELG, n.d.). Properties
flooding but will also Cove have already been of accommodation and in high risk erosion zones
increase erosion of identified as experiencing protection strategies are vulnerable to seawater
coastline areas. Coastal coastal erosion in Saint may also deter property contamination in drinking
erosion can threaten John (Figure 13). New owners, leaving retreat as wells and permanent loss
homes, businesses, Brunswick coastlines are the only option. of land. Ultimately, coastal
bridges, roads, and eroding at 0.59 to 0.88 Grey infrastructure in erosion, exacerbated
historic sites in coastal metres per year due to sea Saint John was designed by sea level rise and
zones. Roads and railways level rise and sensitivity to accommodate a 0.7 increased storm surge,
built near shorelines are to storm surges (O’Carroll metre rise in sea level. leads to negative impacts
now recognized to be and Bérubé, n.d.). In areas However, with sea level on harbours, native
vulnerable to coastal that experience instability, rise projected to reach species, and nearby homes
erosion and flooding. slope movement can be 0.86 metres rise by and businesses (NBDELG,
Repairs and consolidation hazardous depending on the year 2100, the City 2014; Lemmen et al., 2016).
of embankments, bridges, the amount of material needs to recognize the
abandoning old roads, being shifted. Monitoring
and relocating routes are of areas experiencing high
expensive adaptation erosion is of significant Hard protection infrastructure includes
responses (Université importance, in order to
dykes, seawalls, rock armouring, or
Virtuelle Environnement et warn residents about
high risk areas that geosystems that consolidate retreating
Développement Durable,
2016). Aside from the may pose danger to coastal zones. Soft infrastructure can be
high costs of damage, commuters, residents, or measures such as heightened conservation
coastal erosion can cut recreationists. efforts or reinstating vegetation
off essential supply In critical areas, the (bioengineering) that will buffer shoreline
chains, limit opportunities City has the option to protection for beaches and wetlands (i.e.
in tourism, curb new protect, accommodate planting willows, maintaining mangroves, or
development, and increase or retreat and accept beach renourishment).
ecological sensitivity the loss of land (Figure
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 21Flood Mitigation Strategies
For Sea Level Rise
Figure 14: Flood mitigation strategies for sea level rise (Lemmen et al., 2016). Sea level rise
describes the
average increase
5.2 Coastal Squeeze marshes, mudflats, and 2018). These corridors in water due to
sand dunes from migrating control the migration melting glaciers,
Coastal squeeze is a term inward (Pontee, 2013). of displaced species, increasing water
that describes the inland Figure 15 shows three reducing the risk of wildlife temperature and
movement of coastal coastal squeeze situations in urban spaces. Educating geologic setting.
wetlands as sea level rises. including (a) where there is homeowners and Storm surge is
As environmental factors, no obstruction, (b) where developers about coastal a temporary
such as wind or waves, a barrier to migration is squeeze can help prevent rise in water
alter the landscape, coastal in place, and (c) where habitat loss by transitioning
occurring during
habitat will naturally a natural obstruction to commercial and residential
landward migration exists. lawns into natural coastal specific weather
reestablish further inland as
an extension of the existing Available plantings (Powell, 2018). conditions.
habitat. The progression of conservation techniques to By monitoring species Problematic
coastal squeeze depends protect ecosystems include movements and coastal situations arise
on the presence of hard coastal restoration and erosion, the negative when these two
infrastructure or natural development of migration impacts of coastal squeeze are combined.
barriers can prevent salt corridors (Borchert et al., can be reduced.
225.3 Storm Surge that have caused severe flood water storage, 5.4 Conclusion
damage to communities storm surge buffering and
Storm surge describes around the Bay of Fundy, coastal erosion control. Adaptations to protect
the temporary rise of such as the Saxby Gale of Research indicates that urban areas or relocate
water levels instigated by 1869 and the Groundhog storm surge amplitude infrastructure due to
severe weather conditions. Day Storm of 1976 where can be reduced by sea level rise are often
Often, a strong onshore tides rose up to 2.5 approximately one foot expensive and involve
wind combined with a metres above predicted for every 1.6 kilometres of collaboration between
low atmospheric pressure levels (Desplanque and vegetated wetland that multiple stakeholders.
system will intensify wave Mossman, 1999). When exists between a coast The challenges created by
amplitudes resulting in high water is experienced and urban development coastal erosion, coastal
shoreline flooding (Natural in combination with (NOAA, n.d.-b). In squeeze, and storm
Resources Canada, 2007). heavier annual situations where natural surge are site specific
Storm surge events pose precipitation the likelihood conservation will not and require long term
a significant financial risk of a 1 in 100-year flooding accommodate projected monitoring. As the water
to the City due to flood event from storm surge storm surge levels, levels rise, the City will
damage, road closures, increases (Public Health the City can use hard have to evaluate and
loss of property, habitat Agency of Canada, 2018). infrastructure (i.e. dykes prioritize the options for
loss, landslides, and debris Conservation of coastal and sea walls) to prepare maintaining the coastline
flow. habitats is a Climate for the coastal impacts. and relocating at-risk
There are several well Change adaptation infrastructure.
documented storm surges strategy that can provide
Predicting storm surge levels can be difficult, but there are tools available for early warning. For
instance, the Smart Atlantic Saint John Inshore Weather buoy has collected meteorological and
oceanographic data since 2015. The buoy enhances public safety and operational efficiency of
harbour activity by providing online access to real-time weather and directional wave data.
No Seawall Present - Saltmarsh Can Migrate Landward
Landward erosion of
seaward edge due to New marsh created
rising sea level
Seawall Present - Landward Migration Prevented
Sea wall Reclaimed land typically
prevents migration used for agriculture
Landward erosion of
seaward edge due to
rising sea level Habatat squeezed
Saltmarsh Sea wall
Naturally rising land - Landward migration prevented Naturally rising land prevents migratio n
Landward erosion of
seaward edge due to
rising sea level Habatat squeezed
Figure 15: Habitat migration scenarios under sea level rise: (a) No seawall is present and new marsh land is created, (b) A seawall
prevents migration and habitat is lost, (c) Naturally rising land prevents migration and habitat is lost (Savard et al, 2016).
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 2324
6. FLOODING
Flooding is the most 6.1 Damage to Urban naturally soak back into least 30 cm below the
frequent natural disaster Built Environment the surface. This makes lowest building openings,
in Atlantic Canada. urban environments ensuring backup power is
Between 2007 and 2017 As discussed in Chapter especially vulnerable to available for wastewater
the Government of 3, Climate Change is flooding and puts pressure pumping stations, building
New Brunswick spent expected to increase on stormwater systems driveways to slope away
$185 million on disaster precipitation resulting in to transport the water from homes and garages,
recovery primarily from more frequent and severe elsewhere. In Saint John, installing backwater valves
flooding events. The Flood flooding in Saint John. facilities vulnerable to in basements, and having
Risk Reduction Strategy Adaptive approaches to flooding include residential heating, ventilation, and
for New Brunswick planning, development and commercial buildings, air conditioning (HVAC)
aims to build resilience and infrastructure sewage treatment, systems installed above
through accurate hazard management can reduce water services, power grade to avoid destruction
identification, old the damage associated generation, industrial or damage to property
infrastructure retrofits, with flood events. activity, communications, (Moudrak and Feltmate,
new infrastructure and healthcare services. 2017).
regulations, and informed The City of Saint
mitigation practices John can plan to reduce
6.1.1 Grey Infrastructure
(GNB, 2014b). In Saint flooding risks by adjusting
John, there are two types building standards to
The term grey
of flooding that can be account for 1 in 100-year
infrastructure is used to
expected: inland flooding storm water levels. The
describe infrastructure
from heavy precipitation Intact Center on Climate
that has low infiltration
and high river flows; and Adaptation provides
capacity and easily
coastal flooding due to sea recommendations for
becomes flooded
level rise or storm surge. municipalities and
during periods of high
This chapter will discuss homeowners to reduce
runoff (Depietri and
inland flooding in Saint flooding in urban
McPhearson, 2017).
John. spaces. A few of their
Municipal infrastructure
suggestions include:
is mostly impermeable,
designing roads to be at
meaning water does not
Figure 16: Road closure during the 2019 spring freshet flooding Figure 17: Grey infrastructure in Saint John includes roads,
of the St. John River (Photo: ACAP Saint John). bridges, railways, buildings, stormwater drainage, and sewers.
These images depict the low infiltration capacity in urban areas
(Photo: ACAP Saint John).
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 256.1.2 Green Figure 18: In 2019, ACAP
Infrastructure Saint John installed a
rain garden on Queen
Square West as a pilot
Green infrastructure, also project for the City.
known as Low Impact Green infrastructure can
Development (LID), include implementing
refers to stormwater rainfall capture systems,
management methods permeable pavement,
that promote infiltration green roofs, bioswales,
and retention rather than and rain gardens (Photo:
methods that focus on ACAP Saint John).
directing surface runoff
into water treatment
facilities, storage ponds, or natural asset restoration 6.1.3 Hybrid Approach infrastructure) to be the
natural systems (Buckland- can be more cost most effective at reducing
Nicks, 2016). Studies effective to maintain then risk in complex urban
The value of grey and
have shown that green engineered structures systems. An example of
green climate adaptation
infrastructure significantly (Depietri and McPhearson, this hybrid approach is
solutions has been
mitigates flooding risk in 2017). Besides the cost, a wetland restoration
assessed by researchers
urban spaces (Depietri the co-benefits of natural coupled with engineering
Depietri and McPhearson
and McPhearson, 2017). In assets include a range of measures (i.e. a small
(2007), who highlight
watersheds with greater ecosystem services that levee, bioswales, rain
the dependence of cities
than 25% impermeable provide flood and erosion gardens, green roofs, or
on natural ecosystems
surfaces, the likelihood control, heat moderation, street trees) to enhance
for urban disaster risk
of a 1 in 100-year flood is pollination, carbon dioxide flood protection while
reduction. The findings
increased to a likelihood of storage, and enhancement taking advantage of low
suggest a hybrid approach
1 in 5 (Trice, 2017). of community well-being. impact development
(green infrastructure
For municipalities, (Table 1).
integrated with grey
green infrastructure and
Hybrid or mixed
Grey Green and Blue
approaches
Blend of biological- Biophysical,
Hard, engineering physical and Ecosystems and their
structures engineering structures services
Allows for some Mainly relying on
Very limited role of ecosystem functions existing or restored
ecosystem functions mediated by ecosystem fuctions and
technological solutions water bodies
e.g. biowales; porous e.g. wetlands
e.g. canals, pipes and pavement; green restoration; installation
tunnels of the drainage roofs; rain gardens; of grass and riparian
system; dikes; constructed wetlands; buffers; urban trees;
wastewater treatment Sustainable Urban stream restoration;
plants; water filtration Drainage Systems rivers, lakes, ponds,
Table 1: Grey, hybrid,
plants or green and blue
(SUDS) oceans and seas infrastructure adaptation
options (Depietri and
McPhearson, 2017).
266.2 Planning for result including property
Flooding damage or contamination
from combined sewer
Flood risk mapping overflows. Green or hybrid
technologies can be used infrastructure approaches
to estimate the extent are recommended as
of potential flooding proactive adaptation
under different scenarios. practices.
These resources are
extremely useful for
emergency preparedness
and adaptation planning.
The Climate Change
Adaptation Plan for Saint
John by ACAP Saint John
will use flood risk mapping
to identify roadways,
residential and commercial
lots, industrial sites, and
other areas at risk for
flooding. These maps can
be used by the City to limit
development in at-risk
areas.
Aside from
development restrictions
in flood-prone areas,
early warning systems
play an increasingly
important role in flood risk
preparedness. The New
Brunswick Emergency
Measures Organization
(NB EMO) has developed
a River Watch program to
alert residents to potential
flooding events and
provide a flood forecasting
system to predict high
water levels on the
Wǝlastǝkw (St. John River)
up to two days in advance.
6.3 Conclusion
In the coming century,
Saint John will experience
higher river flows and
heavier precipitation
creating flooding
challenges that we are not
currently prepared for.
Flood risk mapping will
play a significant role in
restricting development
and building awareness
for homeowners living in
floodplains. Adaptation
is required to reduce the
negative impacts that can
UNDERSTANDING CLIMATE CHANGE IN SAINT JOHN 2728
7. URBAN WATER QUALITY AND SECURITY
The quality and availability world (Giudice & Broster, in precipitation patterns 7.2.1 Cyanobacteria
of drinking water is of 2006). This has a direct can diminish freshwater
primary concern for effect on human health supplies (Government Cyanobacteria, sometimes
municipalities who rely and industrial sectors of New Brunswick, referred to as blue-green
on local aquifers and (including agriculture, n.d.). Warmer annual algae, has been observed
surface ponds to sustain forestry, and fisheries) temperatures and lower in New Brunswick
residential needs. In Saint resulting in increased summer river levels waterways, and can
John, drinking water is demand on freshwater can alter water quality, release cyanotoxins which
sourced privately from resources. In Saint creating more favourable are toxic to both humans
wells or through Saint John, surface reservoirs conditions for bacterial and animals. Exposure
John Water, which is for drinking water are growth and harmful algal can result in itchy
sourced from surface monitored for saltwater blooms (HABs). As well, eyes and skin, rashes,
reservoirs in Spruce Lake intrusion. increased stormwater blisters, nausea, fever,
and Loch Lomond. Various strategies runoff can introduce vomiting, gastrointestinal
can be employed by local pollutants, viruses, and issues, headaches, and/
governments in areas sewage backup into or dizziness (NBDELG,
According to the impacted by saltwater drinking water reservoirs 2018b). If drinking
United Nations, intrusion. Desalination (Fann et al., 2016). water reservoirs are
plants are facilities where In Saint John, contaminated by
water security is
salt and minerals are flooding of stormwater cyanobacteria, the water
the capacity of removed from saline systems can cause is unsafe for consumption
a population to water. City planners may combined sanitary and until the bloom has
ensure sustainable favour relocation and stormwater systems to subsided. Using water
access, changes to zoning laws backup and contaminate contaminated with
availability and over desalination because waterways. After a cyanobacteria to bathe,
quality of water of its costliness which heavy rainfall, faecal wash clothes, or clean
necessary to is estimated to $0.25 to coliform levels are is not recommended.
“sustaining $0.50 per resident per commonly observed above In addition, fish from
livelihoods, day in Canada (Université recommended guidelines contaminated waters
Virtuelle Environnement (ACAP Saint John, should not be consumed.
human well-
et Développement 2017). Increased effort Monitoring and education
being, and Durable, 2016). Saltwater to separate combined around cyanobacteria is
socio-economic intrusion is a growing sewer infrastructure and necessary to ensure the
development, concern in Saint John, monitoring of waterways safety of residents in Saint
for ensuring specifically the West Side are actions required to John.
protection against drinking water supply. By improve water quality in
water-borne observing invasive species, Saint John. Processing
pollution and groundwater quality, and water through a treatment 7.3 Ocean Warming and
water-related changes in coastal habitats facility can reduce Acidification
disasters, and and species, City officials hazards in municipal
could be alerted about drinking water sources. Similar to the atmosphere,
for preserving
changes in the saltwater- However, when detected, Earth’s oceans absorb
ecosystems” freshwater interface toxins can be costly to
(United Nations CO2 from the atmosphere.
before the most severe remove (United States As a result of increased
Water, 2013). impacts are felt. Environmental Protection GHG emissions, excess
Agency, 2018). Routine CO2 dissolves in oceans
monitoring is undertaken where it breaks down to
7.1 Saltwater Intrusion 7.2 Water Quality and by Saint John Water to carbonic acid, carbonates
Availability reduce health hazards that and bicarbonate. Higher
Saltwater intrusion occurs can result from exposure CO2 quantities have
when seawater enters into Other than saltwater or consumption. caused ocean acidity to
the coastal groundwater intrusion, changing climate rise by 30% since the
system and is a recognized conditions pose significant beginning of the industrial
hazard to coastal risk to urban water quality revolution (Université
communities around the and availability. Changes Virtuelle Environnement et
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