The intensity and frequency of flood are continuously increasing due to climate change.
Cities
across the world are susceptible to flood causing devastating damages to infrastructure and
human life. Almost every country has taking measures to mitigate climate change primarily.
However, due to urgency posed by climate change driven flood risk requires more holistic
approach focusing on both mitigation and adaptation measures and synergy between these
measures. Theory of urban resilience to flood has proposed a paradigm shift in response to flood
by cities. Ecological resilience such as living with flood, nature-based solution for flood
adaptation, and coping with flood due to community learning and experiences are more effective
measures than engineering resilience, such as dykes, flood wall, dam, etc. This paper analyses
critically the relevance of this theory and importance of level of resilience of cities for protection
at flood rather than flood resistance.
1 Introduction
Climate change is continuously posing risks such as increase in global temperature,
sea level rise, irregular precipitation, storm surge, frequent flooding, and severe
drought resulting in risk and vulnerability to communities especially the low-income
groups, tribal and primitive groups, women, and children (Lee et al. 2020). To reduce
the climate change-related risks, many mitigation and adaptation measures have been
taken by the governments at national, provisional and city level as identified by
United Nation Framework Convention of Climate Change (UNFCC 1997). Not only
the government, but civil societies, non-profit organization (NGO), informal groups
and individual level actions are inevitable due to urgency posed by climate change
(Klein et al. 2007). Before going into the details of the current theory and framework,
it is important to understand the concept of climate change mitigation and climate
adaptation. The climate change mitigation can be attributed to the measures applied to
reduce the greenhouse gas emission, which is the primary reason for global climate
change, and increase the sink for carbon sequestration (UNFCCC; United
Nation 1997). Therefore, the mitigation efforts are primarily focused on the dual
mechanism i.e., reducing (Greenhouse Gas) GHG emission on one hand and
increasing carbon sink through green cover on the other hand. Whereas the climate
adaptation measures are taken to reduce the impact of climate change through
reduction in vulnerability and risk related to human and material loss. Previously,
maximum efforts were focused on climate change mitigation, but it is now established
that to meet the target to limit the earth temperature rise within 1.5 °C (Paris
Agreement 2016; UNFCCC), mitigation efforts will not be sufficient, and therefore,
adaptation measures are unavoidable. In recent years, there is a complete paradigm
shift from trade-off between climate mitigation and climate adaptation measures to
synergy in both approaches in cities, especially in Europe and North America.
The widely researched and applied Conventional Theory of Collective Action to
climate change mitigation emphasizes that no one will change behaviour voluntarily
to reduce GHG emission, but an external authority is required to enforce the rule to
achieve the targets (Ostrom 2010). The term “collective action” refers to decisions
taken independently with outcome affecting everyone involved. However, this theory
has two prominent limitations: (1) there is very less empirical evidence related to
socio-environmental dilemma, and (2) it does not explain sufficiently the small,
medium, and large level mitigation benefits other than that of global level
(Ostrom 2010). Ostrom (2010) proposed the Polycentric System theory to explain
climate change mitigation response from global to local level. She explains
polycentricity as connecting decision making done independently in multiple
government authorities through competitive relationship, contractual and cooperative
undertaking, and conflict resolution, so that they function coherently in a predictable
manner in a system. The Polycentric system relies on innovation, learning from each
other, trust, and cooperation among the participants to achieve effective, equitable and
sustainable outcome related to collective good, such as climate change mitigation,
even without formal government intervention (Toonen 2010). Thus, the polycentric
system considers the efforts taken by national, regional, and city level governments
along with steps taken by individual, communities, and NGOs. This theory explains
the climate mitigation measures taken at local level, such as energy efficient
construction to reduce energy bills, which ultimately reduce the GHG emission (Kates
and Wilbanks 2003). Another example is the model of Buiksloterham neighbourhood
in Amsterdam, where the community has taken measure for energy efficiency, waste
recycle and use of waste material to reduce impact of climate change.
The climate adaptation can be explained through the theory related to resilience due to
hypothesis that a resilient system is better adapted to external shock. Theory of Urban
Resilience to Flood (Liao 2012), which is explained in detailed in second part of this
paper, can be applied for climate change adaptation. The theory is related to
adaptation to the risks caused due to climate change by facing them rather resisting
them. To understand this theory, it is important to first understand the concept of
resilience. Resilience is the ability of an individual or a community to adapt and
recover from climate change or hazards (Doorn 2017; Saja et al. 2019). In this sense,
resilience can involve measures taken after the event has taken place or planning
measure implemented even before the event (Bogardi and Fekete 2018; Lopez et
al. 2019). Most of our adaptation responses are based on engineering resilience such
as constructing flood barriers to avoid extreme events, but the theory emphasizes the
need for ecological resilience acquired through nature-based solution and continuous
learning built on indigenous knowledge to lead to sustainable solutions. Nature-based
solutions have been described as the key to solving the three critical challenges of
Anthropocene: mitigating the impacts of climate change, protecting the biodiversity of
the planet, and ensuring the well-being of human beings (Seddon et al. 2020). Instead
of depending upon engineering methods to tackle the impact of climate change,
nature-based solutions try to use ‘ecosystems and the services they provide to address
climate change, natural disasters etc.’ (Cohen-Shacham et al. 2016). For example,
flood adaptation should focus on urban resilience to flood rather resistance to flood.
Such type of adaptation can also be called ecological resilience. Engineering
resilience relies on capacity of cities to bounce back after the extreme flood event,
ecological resilience is based on remaining in the same regime after such event
(Liao 2012). The concept of resist, delay, storage, and discharge-based water
management in The Netherlands (Dai et al. 2018) is a unique example of adaptation
towards sea level rise and excess flooding due to climate change. The trade-off,
synergy, and dynamics between mitigation and adaptation is explained in the last part
of the paper.
Nature-based Solutions also have the added benefit of integrating climate change
adaptation strategy with sustainability goals. For example, an engineering resilience to
urban flood may include building of dams, dykes or high level pledges to
afforestation. However, none of these is sustainable as we cannot predict that the dam
or dyke will never be breached and high level pledge for afforestation can lead to
planting of monoculture non-native invasive species of trees that cause long term
damage to soil and biodiversity and compromise carbon storage. Nature-based
solution on the other hand will include sustainable management of current forest to
prevent forest degradation and deforestation and thereby reducing the probability of
floods (Seddon et al. 2019). Similarly, the Special Report on Climate Change and
Land prepared by Intergovernmental Panel on Climate Change (IPCC 2019) noted the
impact of climate change on land degradation and concluded that climate change is
increasing pressure on land and that various forms of sustainable land management
could solve these problems (Mechler et al. 2020). Seddon et al. (2021) argue that
many of the sustainable land management practices described by the IPCC are
actually nature-based solutions.
Nature-based solutions provide a plethora of novel solutions to problems associated
with climate change. An added benefit of nature-based solutions is that it is generally
developed in close association with the community living in affected areas. In this
way, nature-based solution use community learning and community participation to
solve local problems.
