This article aims to present what and how to do to promote cities planning capable of facing extreme weather events. Floods have been recurring in cities in several countries around the world, including Brazil. There is a drastic change in the Earth's climate thanks to global warming, which is contributing to the occurrence of floods in cities that are recurring in an increasingly catastrophic way in their effects. The floods that devastated some cities in western and southern Germany, Henan in China and London in England in 2021 and, currently, in Rio Grande do Sul demonstrate the vulnerability of highly populated areas to catastrophic floods. Water-related disasters caused worldwide losses of US$306 billion between 1980 and 2016. To cope with extreme weather events in cities, flood control must be carried out, which concerns all methods used to reduce or prevent the harmful effects of water action. Structural measures must be adopted with engineering works aimed at correcting and/or preventing problems arising from floods and non-structural measures which are those that seek to prevent and/or reduce the damage and consequences of floods, not through engineering works, but through the introduction of standards, regulations and programs that aim, for example, to regulate land use and occupation, implementation of alert systems and public awareness. The municipal government plays a fundamental role in preventing flooding, floods and floods in cities. To this end, a municipal development master plan must be drawn up that includes, among other measures, the adoption of solutions to minimize or eliminate the risks faced by the population, the systematic identification of risk areas in order to establish population settlement rules. Three bodies are essential in flood prevention actions in a municipality: 1) the municipal civil defense body; 2) the body responsible for the meteorological service responsible for reporting the climate forecast for the city and/or region; and, 3) community civil defense centers, which are people who work voluntarily in civil defense activities.

1. 1
HOW TO PLAN CITIES TO COPE WITH EXTREME WEATHER EVENTS
Fernando Alcoforado
Abstract: This article aims to present what and how to do to promote cities planning capable of facing extreme
climate events.
Keywords: Global warming; Global climate change; Causes of extreme weather events; Impacts of extreme
weather events on cities; How to prepare cities against extreme weather events; Cities planning required to face
extreme weather events.
1. Introduction
This article aims to present what and how to do to promote cities planning capable of
facing extreme weather events. The occurrence of floods in cities in several countries
around the world has been recurring. There is a drastic change in the Earth's climate
thanks to global warming, which is contributing to the occurrence of floods in cities that
are recurring in an increasingly catastrophic way in their effects. The floods that
devastated some cities in western and southern Germany, Henan in China and London in
England in 2021 demonstrate the vulnerability of highly populated areas to catastrophic
flooding [2].

Fernando Alcoforado, awarded the medal of Engineering Merit of the CONFEA / CREA System, member
of the Bahia Academy of Education, of the SBPC- Brazilian Society for the Progress of Science and of
IPB- Polytechnic Institute of Bahia, engineer from the UFBA Polytechnic School and doctor in Territorial
Planning and Regional Development from the University of Barcelona, college professor (Engineering,
Economy and Administration) and consultant in the areas of strategic planning, business planning, regional
planning, urban planning and energy systems, was Advisor to the Vice President of Engineering and
Technology at LIGHT S.A. Electric power distribution company from Rio de Janeiro, Strategic Planning
Coordinator of CEPED- Bahia Research and Development Center, Undersecretary of Energy of the State
of Bahia, Secretary of Planning of Salvador, is the author of the books Globalização (Editora Nobel, São
Paulo, 1997), De Collor a FHC- O Brasil e a Nova (Des)ordem Mundial (Editora Nobel, São Paulo, 1998),
Um Projeto para o Brasil (Editora Nobel, São Paulo, 2000), Os condicionantes do desenvolvimento do
Estado da Bahia (Tese de doutorado. Universidade de
Barcelona,http://www.tesisenred.net/handle/10803/1944, 2003), Globalização e Desenvolvimento (Editora
Nobel, São Paulo, 2006), Bahia- Desenvolvimento do Século XVI ao Século XX e Objetivos Estratégicos
na Era Contemporânea (EGBA, Salvador, 2008), The Necessary Conditions of the Economic and Social
Development- The Case of the State of Bahia (VDM Verlag Dr. Müller Aktiengesellschaft & Co. KG,
Saarbrücken, Germany, 2010), Aquecimento Global e Catástrofe Planetária (Viena- Editora e Gráfica,
Santa Cruz do Rio Pardo, São Paulo, 2010), Amazônia Sustentável- Para o progresso do Brasil e combate
ao aquecimento global (Viena- Editora e Gráfica, Santa Cruz do Rio Pardo, São Paulo, 2011), Os Fatores
Condicionantes do Desenvolvimento Econômico e Social (Editora CRV, Curitiba, 2012), Energia no
Mundo e no Brasil- Energia e Mudança Climática Catastrófica no Século XXI (Editora CRV, Curitiba,
2015), As Grandes Revoluções Científicas, Econômicas e Sociais que Mudaram o Mundo (Editora CRV,
Curitiba, 2016), A Invenção de um novo Brasil (Editora CRV, Curitiba, 2017), Esquerda x Direita e a sua
convergência (Associação Baiana de Imprensa, Salvador, 2018), Como inventar o futuro para mudar o
mundo (Editora CRV, Curitiba, 2019), A humanidade ameaçada e as estratégias para sua sobrevivência
(Editora Dialética, São Paulo, 2021), A escalada da ciência e da tecnologia e sua contribuição ao progresso
e à sobrevivência da humanidade (Editora CRV, Curitiba, 2022), a chapter in the book Flood Handbook
(CRC Press, Boca Raton, Florida United States, 2022), How to protect human beings from threats to their
existence and avoid the extinction of humanity (Generis Publishing, Europe, Republic of Moldova,
Chișinău, 2023) and A revolução da educação necessária ao Brasil na era contemporânea (Editora CRV,
Curitiba, 2023).

2. 2
The catastrophic floods that swept through Europe and China recently are a wake-up call
that stronger dams, dikes and drainage systems are as urgent as long-term climate change
prevention measures because once-rare weather events are increasingly increasingly
common. Drastic cuts in greenhouse gas emissions are certainly necessary to combat
climate change and will not cool the planet in the short to medium term. However, until
the Earth's climate stabilizes, each country will need to prepare its cities to face extreme
climate events [2]. In many countries, flood-prone rivers need to be carefully managed.
Defenses such as dikes, reservoirs and dams need to be used to prevent rivers from
overflowing their banks.
Governments need to admit that the infrastructure they have built in the past for cities,
even in more recent times, is vulnerable to these extreme weather events. There are
solutions that can be adopted by governments to protect cities affected by extreme
weather events as a result of global warming and the resulting global climate change,
which tends to be catastrophic. To deal with the increasingly frequent floods,
governments need to act simultaneously in three directions: the first is to combat global
climate change; the second consists of preparing cities to face extreme climate events and,
the third, consists of implementing a sustainable society at national and global levels [2].
2. Causes of extreme weather events
Extreme weather events result from global warming. Global warming is a far-reaching
climate phenomenon - an increase in the Earth's average surface temperature that has been
occurring over the past 150 years. The IPCC (Intergovernmental Panel on Climate
Change), established by the UN (United Nations), says that much of the warming
observed on the planet is due to the increase in the greenhouse effect and there is strong
evidence that global warming is due to human activity. Many meteorologists and
climatologists consider it proven that human action is actually influencing the occurrence
of the phenomenon. There is no doubt that human activity on Earth causes changes in the
environment in which we live [1]. Many scientists consider that the increase in the planet's
average temperature results from the greenhouse effect, which is responsible for the
severe effects of climate change, resulting in inclement rainfall and consequent floods.
Global warming and the consequent global climate change, which tends to worsen, are
contributing to the occurrence of intense rains and floods across the planet. Due to global
warming, the atmosphere retains more moisture, which means that when rain clouds
become dense, more water is released. By the end of the 21st century, storms of great
magnitude will be more frequent, according to a study published by the journal
Geophysical Research Letters, using computer simulations [2]. Floods are caused by
many factors such as heavy rainfall, strong winds on the water, unusually high tides,
tsunamis or dam failures, rising levels of retention ponds or other structures that contain
water. Periodic flooding occurs in many rivers, forming a surrounding region known as
the floodplain. During times of rain or snow, some of the water is retained in ponds or in
the soil, others are absorbed by grass and vegetation, some evaporate and the remainder
travels over the land as surface runoff [5].
Floods occur when lakes, riverbeds, soil and vegetation cannot absorb all the water. Water
then escapes from the land in quantities that cannot be transported to stream channels or
retained in natural ponds, lakes and artificial reservoirs. About 30% of all rainfall is in
the form of small runoffs – some of which can be increased by water from any melted
snow where it exists. River flooding is usually caused by heavy rains and sometimes
without warning, they are called flash floods. Flash floods usually result from heavy

3. 3
rainfall in a relatively small area, or if the area was already saturated with previous
precipitation [5].
Severe winds over water are another cause of flooding. Even when rain is relatively light,
the shores of lakes and bays can be flooded as a result of strong winds such as during
hurricanes that blow water into coastal areas. Another cause is the unusually high tides
that sometimes occur in coastal areas when they are inundated by unusually high tides,
especially when compounded by strong winds and storm surges [5]. Many of these
environmental impacts result from the unsustainability of society's current development
model. The unsustainability of society's current development model stems from the fact
that it is responsible for the rapid increase in global temperatures, the depletion of the
planet's natural resources and the rise in sea levels on a greater scale in the 21st century
than in 10,000 years ago since the last ice age [4].
3. The impacts of extreme weather events on cities
Floods cause many impacts. They damage property and endanger the lives of humans and
other living beings. Rapid water runoff causes soil erosion and concomitant sediment
deposition in several locations. Fish spawning grounds and other wildlife habitats can
become polluted or completely destroyed. Some high and prolonged floods can
compromise vehicle traffic in areas that do not have elevated roads. Floods can interfere
with drainage and the economic use of land, such as interfering with agriculture.
Structural damage can occur to bridge piers, sewer systems and other structures in the
flood area. Water navigation and hydroelectric power are often hampered. Financial
losses due to flooding are typically millions of dollars each year [5].
An important impact resulting from flash flooding is landslides. A landslide is a
geological and climatological phenomenon that includes a wide spectrum of ground
movements, such as rockfalls, depth slides and debris flows. Landslide is actually just
one category of so-called mass movements, which involves the detachment and transport
of soil or slope rock material. Three influencing factors can be considered in the
occurrence of landslides [2]:
• Type of soil with its constitution, granulometry and level of cohesion;
• Soil slope that defines the angle of repose, according to the weight of the layers,
granulometry and level of cohesion;
• Water-soaked soil that contributes to increasing the weight of specific layers, reducing
the level of cohesion and friction, also responsible for the consistency of the soil and
lubricating the sliding surfaces [2].
To prevent soil sliding, one of the measures is to ensure that the water that runs down the
slopes of the mountains drains and loses speed or infiltrates the soil through the use of
vegetation. Another, safer, measure is to build terraces in the form of steps to protect the
soil from rainwater. Finally, you can use cable-stayed walls, which are robust walls made
mainly with concrete and which, in parallel, require interventions in the ground to support
the work [2]. Floods that occurred in many cities around the world reveal the
incompetence and irresponsibility of public authorities in not planning the city to face
extreme weather events. It is not necessary to demonstrate that flooding causes many
extremely negative impacts.
Water-related disasters represent 90% of all disasters in number of people affected
worldwide. Social and economic costs have increased in recent decades and, according

4. 4
to speakers at the High Level Panel on Water and Natural Disasters at the 8th World
Water Forum, the trend will continue to increase if action is not taken to resolve the
problem. By 2017, water-related natural disasters caused global losses of US$306 billion.
Between 1980 and 2016, 90% of disasters are climate-related. In 2016, of global losses,
31% were due to storms, 32% attributed to flooding and 10% to extreme temperatures
[2]. Floods are responsible for the deaths of almost twice as many people as tornadoes
and hurricanes combined [2].
4. How to prepare cities against extreme weather events
To deal with extreme weather events in cities, flood control must be carried out. Flood
control concerns all methods used to reduce or prevent the harmful effects of water action.
Some of the common techniques used for flood control are the installation of rock berms
to help with the stability of slopes to hold blocks, rock rip-raps or rock fill, sand bags,
maintaining normal slopes with vegetation or applying cement. on soil with steeper slopes
and drainage construction or expansion. Other methods include dikes, dams, retention or
detention basins. After the 2005 Hurricane Katrina disaster in the United States, some
areas prefer not to have levees as flood control. Communities chose to improve drainage
structures with detention basins [6].
Some flood control methods have been practiced since ancient times. These methods
include planting vegetation to retain excess water on slopes to reduce water flow and
building alluviums (artificial channels to divert flood water), building dikes, dams,
reservoirs or tanks to store extra water during periods of flooding In many countries,
rivers subject to flooding are often carefully managed. Defenses such as dikes, reservoirs
and dams are used to prevent rivers from overflowing their banks. A dam is one of the
flood protection methods, which reduces the risk of flooding compared to other methods
as it can help prevent damage. However, it is best to combine levees with other flood
control methods to reduce the risk of a collapsed levee. When these defenses fail,
emergency measures such as sandbags or portable inflatable tubes are used. Coastal
flooding has been controlled in Europe and North America with defenses such as ocean
walls or barrier islands which are long strips of sand usually parallel to the coast [6].
The engineering works that can prevent and mitigate the effects of flooding in cities are
as follows: 1) Construction of large swimming pools, which are large underground water
tanks to store water; 2) Mandatory placement of permeable drainage floors in huge
parking lots in shopping malls, supermarkets and cinemas, to allow water infiltration into
part of the soil, with the same action being taken for monuments and spaces around
buildings; 3) Use of drains and gutters around all houses to divert rainwater to a reservoir
or disposal area; 4) Maintenance, whenever possible, of some green areas so that water is
absorbed by the soil; 5) Rectification of rivers and streams, construction of dams and
canals on large rivers that extend their containment basins; 6) Meteorological monitoring
of the city's climate to identify the occurrence of extreme events; and, 7) Implementation
of a civil defense system that must be able to at least alert people and have a scheme to
remove them from their homes in time with some belongings and accommodate them [6].
Taking care to avoid flooding in urban areas is: 1) keeping streets and sidewalks always
clean; 2) clean and unclog drains and rainwater drainage; 3) keep rain channels free of
tree branches and leaves to avoid clogging and, consequently, the return of water; 4) place
garbage bags on the sidewalks only close to the moment the garbage collection truck
arrives, preventing them from being pulled into the drain when it rains; 5) have a drainage
pump on hand if flooding cannot be avoided; and 6) use Dutch and British flood-proof

5. 5
technology as a floating amphibious house that allows it to float in the same way as a boat
[6].
Hydrology experts recommend that, to avoid flooding in urban areas, the following
measures should be adopted: 1) Combating erosion by minimizing sedimentation of
natural and constructed drainage through rigorous and extensive control of soil erosion
and irregular disposal of urban waste and construction debris, as well as the expansion of
river channels; 2) Combating soil sealing with the creation of domestic and commercial
reservoirs, as well as the expansion of green areas; 3) Prohibition of traffic on avenues
with large vehicle movements when nearby rivers overflow; 4) Implementation of
avenues covered by vegetation so that, in cases of river or stream overflow, the water
would be absorbed by the unpaved soil; 5) Construction of large swimming pools to
receive rainwater and mini swimming pools in houses and buildings; 6) Investment in
small and large streams in the urban center to receive the increase in water and act as
containment barriers; 7) Review of occupied areas with continuous land use planning;
and 8) Action and planning with the development of a plan to deal with the occurrence of
floods, as well as extreme climate variations, and construction of reservoirs capable of
storing billions of cubic meters of water and its use for non-potable purposes [6].
Correction and prevention measures to minimize damage caused by floods are classified,
according to their nature, into structural and non-structural measures. Structural measures
correspond to work that can be implemented to correct and/or prevent problems arising
from flooding. Non-structural measures are those that seek to prevent and/or reduce the
damage and consequences of floods, not through work, but through the introduction of
standards, regulations and programs that aim, for example, to discipline the use and
occupation of land, implementation of alert and population awareness systems [6].
Structural measures comprise engineering works, which can be characterized as intensive
and extensive measures [6]. Intensive measures, depending on their purpose, can be of
four types:
• Acceleration of outflow: pipelines and related works;
• Flow delay: reservoirs (retention basins), restoration of natural gutters;
• Flow diversion: bypass tunnels and diversion channels;
• Individual actions to make buildings flood-proof.
On the other hand, extensive measures correspond to small water storage in the basin,
restoration of vegetation cover and control of soil erosion along the drainage basin [6].
Structural measures can create a sense of false security and even lead to the expansion of
occupation of flood areas. Non-structural actions can be effective at lower costs and
longer horizons, as well as seeking to discipline territorial occupation, people's behavior
and economic activities [6].
Non-structural measures can be grouped as follows [6]:
• Actions to regulate land use and occupation;
• Environmental education focused on controlling diffuse pollution, erosion and waste;
• Flood insurance;
• Flood warning and forecast systems.

6. 6
By delimiting areas subject to flooding depending on the risk, it is possible to establish
zoning and the respective regulations for construction, or for possible individual
protection works (such as the installation of floodgates, watertight doors and others) to
be included in existing buildings. Likewise, some areas may be expropriated to be used
as squares, parks, parking lots and other uses [6]. In certain cases where structural
measures are technically or economically unfeasible (or even untimely), non-structural
measures, such as warning systems, can reduce the expected damage in the short term,
with small investments [6].
Issues related to structural and non-structural flood prevention measures were a
prominent topic at the 2nd Asia-Pacific Water Summit in Chiang Mai. There is a wide
gap between groups that prefer "structural" solutions to disaster management and those
that prefer "structural" solutions to disaster management "non-structural". Structural
solutions include engineered solutions such as redesigning buildings and designing
physical barriers for disaster events in order to reduce damage. Non-structural solutions
include social solutions such as early warning, evacuation planning, and emergency
response preparedness [6].
Structural groups, which are often made up of engineers, insist that only structural
solutions can prevent economic losses and contribute to the nation's development. On the
other hand, non-structural groups often warn: Do not trust engineering solutions, because
at some point they will not work. Early warnings, rapid evacuations and emergency
responses are easy investments. The term “resilience” has recently been introduced into
the dialogue on disaster management. The word implies that people must accept the
damage of a disaster and have plans in place for recovery. As you know, alert, evacuation
and emergency response can help save lives; however, it cannot protect physical
properties and assets. For structural groups, non-structural solutions are not investments.
Investments must contribute to development and therefore reduce future expenses.
Structural solutions can protect people’s lives and property [6]. It is a false dilemma to
choose between structural and non-structural measures to deal with flooding. We must
opt for both measures. Non-structural measures should be taken in conjunction with
structural measures as a precaution against the latter's failure to do so [6].
The United Nations IPCC has warned that sufficiently limiting man-made global
warming will require rapid, far-reaching and unprecedented changes in all aspects of
society in order to avoid dramatic global consequences, including rising sea levels, deaths
of coral reefs and human casualties due to extreme heat. The special report - published
by the United Nations Intergovernmental Panel on Climate Change - assessed what it will
take to limit global temperature rise to no more than 2.7°F (1.5°C) above pre-industrial
levels, according to the 2015 Paris Agreement. Scientists consider temperature to be a
tipping point at which many severe effects of global warming will be realized [7].
The IPCC report called climate change an urgent and potentially irreversible threat to
human societies and the planet, and warned that delaying action would make it impossible
to limit warming to 2.7°F (1.5°C). While the pace of change that would be needed to limit
warming to [2.7°F] can be traced back to the past, there is no historical precedent for the
scale of transitions needed, particularly toward a socially and economically sustainable
one, the report says. Resolving such issues of speed and scale would require people's
support, public sector interventions, and private sector cooperation [7].
5. Cities planning required to face extreme weather events

7. 7
To deal with extreme weather events, it is essential that governments prepare contingency
plans to evacuate populations that may be affected as a result of floods, thus minimizing
deaths and losses resulting from them. It is up to governments to inspect and monitor
dams and adopt measures to prevent their failure. A large part of the resources should be
allocated to prevention and not to cover losses as is currently the case because much less
is spent on preventing floods than on rebuilding buildings and infrastructures. The
municipal government plays a fundamental role in preventing flooding in cities. To this
end, a municipal development master plan must be drawn up that includes, among other
measures, the adoption of solutions to minimize or eliminate the risks faced by the
population, the systematic identification of risk areas in order to establish population
settlement rules. In addition, it must monitor risk areas, avoiding dangerous settlements,
apply fines when residents do not comply with recommendations, prepare an evacuation
plan with an alarm system and indicate areas that are safe for construction, based on
zoning. Every resident must be informed of what and how to do to avoid being affected
by floods [1].
Three bodies are essential in flood prevention actions in a municipality: 1) the municipal
civil defense body, which is responsible for executing, coordinating and mobilizing all
civil defense actions in the municipality, whose main task is to know and identify the
risks of disasters in the municipality, preparing the population to face them by drawing
up specific plans; 2) the body responsible for the meteorological service responsible for
reporting the climate forecast for the city and/or region; and, 3) community civil defense
centers, which are people who work voluntarily in civil defense activities, to collaborate
with the civil defense body aiming at community participation, preparing it to respond
promptly to disasters. It is up to the mayor to determine the creation of the civil defense
body [1].
Sustainability is a term used to define human actions and activities that seek to meet the
present needs of human beings without compromising the future of the next generations.
In the case of floods, sustainability is achieved in their management when the
environment affected by them is preserved for use by current and future generations with
the adoption of prevention and precautionary measures against their occurrence.
Sustainability is achieved in flood management with the development of prevention,
precautionary and risk management plans, in addition to the intensification of inspection.
To deal with flood risks, it is essential that prevention and precautionary measures are
adopted to avoid catastrophic events. The Preliminary Environmental Impact Assessment
of Floods is an important instrument for formulating civil defense plans, as it is used to
assess, predict and prevent greater economic and social damage resulting from floods. It
is worth noting that preventive or precautionary measures should underpin risk
management policies and, above all, should be present in civil defense proposals and
actions to combat floods [1].
Sea level rise is one of the best-known threats resulting from global warming and climate
change. As humanity pollutes the atmosphere with greenhouse gases, the planet warms.
As they do, ice sheets and glaciers melt and warming seawater expands, increasing the
volume of water in the world's oceans. Globally, sea level rise could have a significant
impact in the coming years. Potential impacts of sea level rise include flooding, erosion
of coastal regions, and submergence of flat regions along the mainland coast and on
islands.
According to Climate Central, a non-profit organization that analyzes and reports on
climate science, made up of scientists and science journalists, which conducts scientific

8. 8
research on climate change and energy issues throughout the 21st century, considers that
levels Global sea levels could increase by between around 61 cm and 2.13 m between
2030 and 2100 if nothing is done to prevent them. However, in some places on the planet
the sea level could rise by up to 3.5 meters. In the extreme case, sea levels could rise by
more than 7 meters if the ice caps, mountain ranges and Greenland melt [8]. The
Greenland ice sheet alone contains enough water to raise sea levels by 7 meters, according
to John Sutter's article “Climate: 9 questions on rising seas” [9]. Projecting where and
when this increase could translate into increased partial flooding and permanent flooding
is important for planning coastal regions and cities.
A new digital model, CoastalDEM, from Climate Central was used to identify flood areas
on the planet. This is a high-precision digital elevation model for coastal areas that
reduces average errors to nearly zero in NASA's widely used SRTM DEM and reveals
flood threats three times greater. CoastalDEM shows that many of the world's coastal
regions are at very low water levels and that rising sea levels could affect hundreds of
millions of people in the coming decades more than previously thought. Based on sea
level projections for 2050, the region of the planet currently home to 300 million people
will fall below the elevation of an average annual coastal flood. By 2100, the region of
the planet now home to 200 million people could be permanently below the high tide line
[8].
What to do to face rising sea levels? The First Street Foundation, which published the
article Solving for Sea Level Rise [8], offers answers with proposed solutions such as
those described below:
Solution 1: Building Seawalls
One solution that cities employ to reduce tidal and storm flooding is the construction of
seawalls. These barriers are generally built at a height of 1.52 meters to 1.83 meters above
sea level. When seawalls or breakwaters age or are damaged by constant exposure to salt
water or wave impact, they need to be reinforced or replaced. They also need to be
reinforced, replaced or built higher as sea levels continue to rise.
Solution 2: Using beaches and dunes as barriers
Similar to seawalls, beaches and dunes can act as a natural wall and reduce the impact of
ocean waves and storms. The longer the beach or the larger the dune, the more water can
be prevented from reaching homes and roads. City rulers can add sand to widen beaches
or to prevent them from eroding. Using this type of natural infrastructure can protect cities
from flooding while maintaining beaches for the community to enjoy.
Solution 3: Raising the level of highways
Raising highways above sea level can help drain water and reduce tidal flooding. To
ensure that higher roads do not channel floodwaters into homes and stores at lower
elevations, city officials often pump stormwater to remove this excess water.
Solution 4: Stormwater pumping
With higher seas, water does not drain into the ocean as easily. Drainage systems are
designed to channel excess rainwater from streets and drain it out to sea, but pressure
from rising sea levels and high tides can push too much water into these pipes, causing
water to leak into the streets. Pumps can speed up the process of removing water from
streets, sucking up floodwater and releasing it back into the sea.

9. 9
Solution 5: Updating Sewer Systems
Floods can disrupt sewage systems and, in particular, threaten septic tanks. As salt water
is corrosive, it can damage tanks and cause sewage to be expelled, creating health risks
for the population. City leaders can upgrade sewer systems so rainwater does not infiltrate
pipes and upgrade septic tanks or replace them with sewer lines.
Solution 6: Creating natural infrastructure
Coastal communities can restore natural infrastructure, which can act as a buffer against
storms and coastal flooding. Natural structures such as barrier islands, coral reefs,
mangroves, sea grass beds and salt marshes can work alone or in conjunction with built
infrastructure such as breakwaters to absorb storm surge. These projects are often cost-
effective, can improve the natural environment for the community, and save important
habitats.
Solution 7: Decreasing the land sinking
Cities can reduce land sinking by limiting groundwater pumping and starting pilot
projects to reverse land sinking by filling empty space in places where groundwater has
been pumped.
Solution 8: Planned relocation of populations
This solution is adopted in some coastal areas that are being lost to storms, rising sea
levels, erosion and land sinking. Although communities are implementing many of the
solutions available to help prevent land loss, relocation of populations in extreme cases
should be considered. This may not be the best option for all coastal communities facing
the imminent threat of sea level rise, but for some, it is the best solution to keep residents
safe.
In addition to the local solutions described above, the measures recommended by the Paris
Climate Agreement should be simultaneously adopted to reduce the global emission of
greenhouse gases (carbon dioxide, nitrous oxide, among others) to avoid global warming
of more than 2 degrees Celsius (°C) by the end of the 21st century [8].
Cities will be better able to face extreme climate events if they are transformed into smart
and sustainable cities. Building smart and sustainable cities means providing rational
management, improving the quality of life for the entire population, sustainable
development of the city and democratization of government decisions with the
participation of the entire population. Every city achieves the status of a smart city when
its managers consider it as a system and use information technology in its planning and
control process, counting on the effective support of its population. Every smart city
requires the use of information technology with the use of various devices connected to
the IoT (Internet of Things) network to manage the city's operations and services
rationally and connect with its citizens [3].
The Internet of Things (IoT, in English) refers to a technological revolution that aims to
connect everyday items used to the world wide web and is one of the main global trends
its use in the administration of a city because it is applicable in solutions ranging from
monitoring public lighting, pedestrians, cyclists, motor vehicles, public transport,
education and health services, among others. The applications of the Internet of Things
are almost endless. Furthermore, IoT will lead to a reduction in waste of public resources
in cities. Driven by the rise of 5G Internet, IoT devices can bring benefits to people,

10. 10
companies and the public sector. However, it is worth highlighting that, to be considered
an IoT solution, a city's administration system needs to have three characteristics: 1)
receive digital data originating from sensors; 2) connect to an external network; and, 3)
process information automatically, that is, without human intervention [3].
A new revolution in the media is about to occur with the use of 5G Internet across the
world, representing to date the greatest advance in communications after a long historical
process of technological evolution. 5G Internet will produce gigantic impacts on the
economy and society. It is an absolutely innovative communications platform with
features that allow machine-to-machine (M2M) communication with great efficiency,
effectiveness, reliability and security. In this sense, it is developed for the internet of
things (IoT), that is, for personal applications, but it also serves as a communications
platform for the development of new and revolutionary applications for industry, cities,
agriculture, transport and the services. The 5G Internet will be a major driver for the
development of Industry 4.0 and the advent of smart cities because it tends to accelerate
the development of technologies, such as the Internet of Things (IoT), artificial
intelligence and machine learning, whose potential will not consist of only in improving
connectivity for people, but allowing communication between objects, which can
decisively transform urban services and spaces [3].
Information technology allows city managers to interact directly with their executing
agencies and the population and monitor what is happening in the city and how the city
is evolving in real time. Information technology should be used to improve the quality,
performance and interactivity of urban services, reduce costs and resource consumption
and increase contact between citizens and government. A smart city can be better
prepared to respond to the challenges faced by its managers and its population. Every city
will achieve the status of a smart city when the objectives of humanizing the city are
achieved by improving the quality of life for the entire population, sustainable
development of the city and democratization of government decisions with the
participation of the entire population [3 ].
Improving the population's quality of life depends on the conditions of their existence in
terms of employment, housing, basic sanitation, urban infrastructure, urban mobility and
access to education, culture, health and leisure services. The sustainable development of
a city will only be achieved when the degradation of natural resources is avoided and
there are clear and comprehensive policies for sanitation, waste collection and treatment,
water management, with collection, treatment, economy and reuse, transport systems that
favor mass transport with quality and safety, actions that preserve and expand green areas,
the use of clean and renewable energy and, above all, transparent public administration
shared with organized civil society. In turn, the democratization of government decisions
with the participation of the entire population will only exist when they become involved
not only in providing data, but also decide on the city's direction [3].
Among the world's smart cities, the following stand out: 1) Amsterdam, which has, since
2009, an interconnected platform through wireless devices to improve the city's decision-
making abilities in real time, reduce traffic, save energy and improve public safety; 2)
Copenhagen, which, in 2014, won the prestigious World Smart Cities Award for its smart
city development strategy aimed at improving air quality, liveability and traffic flow; 3)
Dubai, which has a project to become a smart city by 2030, with transport initiatives that
include driverless vehicles, digitalization of government, business and customer
transactions; and, 4) Stockholm, which aims to create a green IT structure to reduce

11. 11
environmental impact, increase the energy efficiency of buildings and traffic monitoring,
among other objectives [3].
It is an imperative need to make cities smart because the city has become the main habitat
of humanity. For the first time in human history, more than half of the population lives in
cities. This number, 3.3 billion people, is expected to surpass the 5 billion mark by 2030.
At the beginning of the 20th century, the urban population did not exceed 220 million
people. Access to jobs, services, public facilities and greater economic and social well-
being is its greatest attraction for all who seek it [3]. A large part of global environmental
problems originate in cities, which makes it difficult to achieve sustainability at a global
level without making them smart [3].
Significant impacts on the environment occur due to the modes of production and
consumption in urbanized spaces. Pollution, traffic jams, violence, unemployment, etc.,
are common in cities. Water pollution is mainly caused by the release of untreated
industrial and domestic effluents. Air pollution is a major problem detected in cities that
results from the release of toxic gases into the atmosphere. The intense flow of cars and
industries is mainly responsible for this type of pollution. Other environmental problems
resulting from urbanization are soil sealing, visual pollution, noise pollution, climate
change, acid rain, lack of environmental sanitation, lack of adequate disposal and
treatment of solid waste, greenhouse effect, among others. The lack of effective urban
planning compromises the quality of life of the urban population. The disorderly growth
of cities generates the occupation of places unsuitable for housing low-income
populations, such as those with high slopes, valley bottoms, among others [3].
The accelerated urbanization and growth of cities, especially since the mid-20th century,
has promoted physiognomic changes on the planet, more than any other human activity.
It is in cities that the social, economic and environmental dimensions of sustainable
development converge most intensely, making it necessary to structure smart cities that
are designed, managed and planned in accordance with the sustainable development
model that aims to meet current needs of the Earth's population without compromising its
natural resources, bequeathing them to future generations. This means that the smart and
sustainable development model in cities must be adopted with the aim of making
economic and social factors compatible with the environment [3].
In the contemporary era, when the problems of global warming can lead to catastrophic
climate change on a planetary scale, every city needs to have a climate change adaptation
plan, especially those subject to extreme events. Coastal cities, for example, must plan
against the predictable rise in ocean levels and worry about landslides on slopes, floods,
etc., resulting from inclement rain. In short, they must have flexibility and adaptability to
new climatic requirements. It is necessary to redesign the urban growth of cities to
integrate it with the natural environment and recover its beaches and rivers that are now
compromised by the release of sewage, so that cities do not receive a hostile response
from the natural environment [3].
Significant impacts on the environment occur due to the modes of production and
consumption in urbanized spaces. Pollution, traffic jams, violence, unemployment, etc.,
are common in cities. Water pollution is mainly caused by the release of untreated
industrial and domestic effluents. Air pollution is a major problem detected in cities that
results from the release of toxic gases into the atmosphere. The intense flow of cars and
industries is mainly responsible for this type of pollution. Other environmental problems
resulting from urbanization are soil sealing, visual pollution, noise pollution, climate

12. 12
change, acid rain, lack of environmental sanitation, lack of adequate disposal and
treatment of solid waste, greenhouse effect, among others. The lack of effective urban
planning compromises the quality of life of the urban population. The disorderly growth
of cities generates the occupation of places unsuitable for housing low-income
populations, such as those with high slopes, valley bottoms, among others [3].
The accelerated urbanization and growth of cities, especially since the mid-20th century,
has promoted physiognomic changes on the planet, more than any other human activity.
It is in cities that the social, economic and environmental dimensions of sustainable
development converge most intensely, making it necessary to structure smart cities that
are designed, managed and planned in accordance with the sustainable development
model that aims to meet current needs of the Earth's population without compromising its
natural resources, bequeathing them to future generations. This means that the smart and
sustainable development model in cities must be adopted with the aim of making
economic and social factors compatible with the environment [3].
After all, what characterizes a smart and sustainable city? It is for the city to be managed
rationally with the support of the population with the use of information technology,
which ensures the population's right to urban land, housing, environmental sanitation,
urban infrastructure, transport and public services, work and to leisure, for current and
future generations and which ensures the population's right to decide on the destiny of
their city. Transforming a city into a smart city means using information technology to
facilitate city management with the collaboration of the population and counting on their
participation in decision-making. The future of cities and their populations therefore
depends on what is done to adopt a new management model with the use of information
technology, promote improved quality of life for the entire population, promote the
sustainable development of city and promote the democratization of government
decisions with the participation of the entire population [3].
The facts of life are increasingly showing the need for the paradigm that has guided the
development of human society since the 1st Industrial Revolution to be profoundly
modified. This is why the current model of society must be replaced by the sustainable
development model, among other measures. Some measures need to be implemented to
stop the current rate of global warming [4]:
• Reduce carbon emissions by 45%
By 2030, global carbon dioxide emissions are expected to be 45% lower than in 2010,
according to the report. Carbon dioxide emissions are expected to be zero by around 2075,
meaning the amount of carbon dioxide entering the atmosphere equals the amount to be
removed. By 2050, emissions of other greenhouse gases, including methane and carbon
black, must be reduced by 35% from the 2010 rate. Emissions would need to decline
rapidly in all major sectors of society, including buildings, industry, transport, energy and
agriculture, forestry and other land uses.
• Remove carbon dioxide from the air
In addition to reducing carbon dioxide emissions, reported carbon dioxide removal
measures include planting new trees and carbon capture and storage, the process by which
carbon dioxide is captured and prevented from entering the atmosphere. Most current and
potential carbon dioxide removal measures could have significant impacts on land,
energy, water or nutrients if implemented on a large scale.
• Use 85% renewable energy and stop using coal entirely

13. 13
The report recommended far-reaching changes to land use, urban planning, infrastructure
systems and energy use – changes that will be “unprecedented in terms of scale”. Climate
scientists have said that renewable energy sources will have to account for 70% to 85%
of electricity production by 2050. Coal use is expected to decline sharply and is expected
to account for almost 0% of global electricity, and gas just 8% . While recognizing the
challenges and differences between national options and circumstances, the political,
economic, social and technical viability of solar energy, wind energy and electricity
storage technologies have improved substantially in recent years. These improvements
signal a possible system transition in electricity generation.
• Plant new forests equal to the size of Canada
Scientists recommend that up to 3 million square miles of grassland and up to 1.9 million
square miles of non-grazing farmland be converted into up to 2.7 million square miles for
energy crops, which can be used to produce biofuels. This would equate to an amount of
land slightly smaller than the size of Australia. The report also recommends adding 3.9
million square miles of forests by 2050, up from 2010 — which is about the size of
Canada.
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2. ALCOFORADO, Fernando. City floods and global climate change. Available
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change-fernando-alcoforado/>.
3. ALCOFORADO, Fernando. How to build smart and sustainable cities.
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<https://www.academia.edu/61050601/HOW_TO_BUILD_SMART_AND_SU
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4. ALCOFORADO, Fernando. Catastrophic Climate Change Requires New
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Available on the website <https://www.linkedin.com/pulse/strategies-deal-
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8. FIRST STREET FOUNDATION. Solving for Sea Level Rise. Disponível no
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9. SUTTER, John. Climate: 9 questions on rising seas, Disponível no website
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climate/index.html>.