Here you can find definitions and descriptions of terms used in this e-Guide.

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  • Adaptation

    The process of adjustment to actual or expected climate, and its effects.

    See also Autonomous Adaptation, EvolutionaryAdaptation, Incremental Adaptation and Transformative Adaptation


  • Adaptation approach

    The approach chosen to achieve the adaptation goals. These are largely political choices regarding the way adaptation should be implemented: e.g. by investing in blue-green or in gray infrastructure, by investments by the city or by private parties, by imposing regulations or by educating the public. Note that an approach may encompass many options for realizing the approach.

  • Adaptation approaches

    The approach chosen to achieve the adaptation goals. These are largely political choices regarding the way adaptation should be implemented: e.g. by investing in blue-green or in gray infrastructure, by investments by the city or by private parties, by imposing regulations or by educating the public. Note that an approach may encompass many options for realizing the approach.

  • Adaptation Assessment

    The practice of identifying options to adapt to climate change and evaluating them, in terms of criteria such as availability, (co-)benefits, costs, effectiveness, efficiency and feasibility

  • Adaptation Options

    The array of strategies and measures that are available and appropriate for addressing adaptation needs. They include a wide range of actions that can be categorized as structural, institutional, or social.

  • Adaptation Pathway

    See Climate Resilient Pathways

  • Adaptation Strategies

    [Adaptation Strategies] include a mix of policies and measures with the overarching objective of reducing vulnerability. Depending on the circumstances, the strategy can be set at a national level, addressing adaptation across sectors, regions and vulnerable populations, or it can be more limited, focusing on just one or two sectors or regions.

  • Adaptive capacity

    (or adaptability)

    The ability of systems, institutions, humans, and other organisms to adjust to potential damage, to take advantage of opportunities, or to respond to consequences.

  • Autonomous Adaptation

    Adaptation in response to experienced climate and its effects, without planning explicitly or consciously focused on addressing climate change. Also referred to as spontaneous adaptation.

  • Cascading Effects

    A sequence of events in which each one produces the circumstances necessary for the initiation of the next. See also Consequence Analysis.


    A sequence of events in which each individual event is the cause of the following event; all the events can be traced back to one and the same initial event

  • Climate

    Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization.

  • Climate Change

    Climate change refers to a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer.

  • Climate Model

    A numerical representation of the climate system based on the physical, chemical and biological properties of its components,\ their interactions and feedback processes, and accounting for some of its known properties.

  • Climate Projection

    A climate projection is the simulated response of the climate system to a scenario of future emission or concentration of greenhouse gases and aerosols, generally derived using climate models.

  • Climate Resilient Pathways

    Iterative processes for managing change within complex systems in order to reduce disruptions and enhance opportunities associated with climate change.

    …an iterative and ongoing approach, informed by a strategic vision, that enables experimentation and learning so that choices along pathways can be altered in response to predefined triggers.

  • Climate System

    The climate system is the highly complex system consisting of five major components: the atmosphere, the hydrosphere, the cryosphere, the lithosphere and the biosphere, and the interactions between them.

  • Co-benefits

    The positive effects that a policy or measure aimed at one objective might have on other objectives, irrespective of the net effect on overall social welfare. Co-benefits are often subject to uncertainty and depend on local circumstances and implementation practices, among other factors. Co-benefits are also referred to as ancillary benefits.

  • Coastal Flooding

    A coastal flood is when the coast is flooded by the sea. The cause of such a surge is a severe storm. The storm wind pushes the water up and creates high waves.

  • Consequence

    The outcome of an event affecting objectives.

  • Consequence Analysis

    Consequence Analysis is estimation of the effect of potential hazardous events.

  • Contextual Vulnerability

    A present inability to cope with external pressures or changes, such as changing climate conditions. Contextual vulnerability is a characteristic of social and ecological systems generated by multiple factors and processes.

  • Coping Capacity

    The ability of people, institutions, organizations, and systems, using available skills, values, beliefs, resources, and opportunities, to address, manage, and overcome adverse conditions in the short to medium term.

    The ability of people, organizations and systems, using available skills and resources, to face and manage adverse conditions, emergencies or disasters.

  • Critical Information Infrastructure

    Critical information infrastructures (‘CII’) should be understood as referring to those interconnected information systems and networks, the disruption or destruction of which would have serious impact on the health, safety, security, or economic well- being of citizens, or on the effective functioning of government or the economy.

  • Critical Infrastructure

    An asset, system or part thereof located in Member States which is essential for the maintenance of vital societal functions, health, safety, security, economic or social well-being of people, and the disruption or destruction of which would have a significant impact in a Member State as a result of the failure to maintain those functions. Organizations and facilities that are essential for the functioning of society and the economy as a whole.

  • Critical Infrastructure Dependency

    CI dependency is the relationship between two (critical infrastructure) products or services in which one product or service is required for the generation of the other product or service

  • Critical Infrastructure Element

    Part of a CI. Can have sub-elements

  • Critical Infrastructure Interdependency

    The mutual dependency of products or services.

  • Critical Infrastructure Protection (CIP)

    All activities aimed at ensuring the functionality, continuity and integrity of critical infrastructures in order to deter, mitigate and neutralise a threat, risk or vulnerability.

  • Critical Infrastructure Sector

    Economic sectors considered critical

  • Cyber Security

    Cyber-security commonly refers to the safeguards and actions that can be used to protect the cyber domain, both in the civilian and military fields, from those threats that are associated with or that may harm its interdependent networks and information infrastructure. Cyber-security strives to preserve the availability and integrity of the networks and infrastructure and the confidentiality of the information contained therein

  • Damage

    Damage classification is the evaluation and recording of damage to structures, facilities, or objects according to three (or more) categories.

  • Decision

    The result of making up one’s mind regarding a choice between alternatives

  • Decision Support

    The structure process of activities that support decision makers and other stakeholders in coping with and resolving problems they are faced with.

  • Decision Support System

    An information system that supports business or organizational decision-making activities.

    Sprague [1] defines a properly termed DSS as follows:

    1. DSS tends to be aimed at the less well structured, underspecified problem that upper level managers typically face;
    2. DSS attempts to combine the use of models or analytic techniques with traditional data access and retrieval functions;
    3. DSS specifically focuses on features which make them easy to use by non-computer-proficient people in an interactive mode; and
    4. DSS emphasizes flexibility and adaptability to accommodate changes in the environment and the decision making approach of the user.

    [1] Sprague, R;(1980). “A Framework for the Development of Decision Support Systems.” MIS Quarterly. Vol. 4, No. 4, pp.1-25.

  • Disaster Risk Management

    The systematic process of using administrative directives, organizations, and operational skills and capacities to implement strategies, policies and improved coping capacities in order to lessen the adverse impacts of hazards and the possibility of disaster.

    Note: This term is an extension of the more general term “risk management” to address the specific issue of disaster risks. Disaster risk management aims to avoid, lessen or transfer the adverse effects of hazards through activities and measures for prevention, mitigation and preparedness.

  • Disruption

    Incident, whether anticipated (e.g. hurricane) or unanticipated (e.g. a blackout or earthquake) which disrupts the normal course of operations at an organization location.

  • Driver (direct and indirect)

    Any natural or human-induced factor that directly or indirectly causes a change to a given system.

    Note: A direct driver is a driver that unequivocally influences ecosystem processes, such as climate change, and can therefore be identified and measured to differing degrees of accuracy.

    An indirect driver is a driver that operates by altering the level or rate of change of one or more direct drivers. [Important indirect drivers include changes in population, economic activity, and technology, as well as socio-political and cultural factors.]

  • Drought

    A period of abnormally dry weather long enough to cause a serious hydrological imbalance. Drought is a relative term; therefore any discussion in terms of precipitation deficit must refer to the particular precipitation-related activity that is under discussion.

  • Ecosystem-based Adaptation (EbA)

    A place-based approach that focuses on the creation, restoration and conservation of ecological structures to provide society with specific services from nature.

  • Efficiency

    The good use of time and energy in a way that does not waste any.

  • Ensemble

    A collection of model simulations characterizing a climate prediction or [climate] projection.

  • European Critical Infrastructure

    Critical infrastructure located in Member States the disruption or destruction of which would have a significant impact on at least two Member States. The significance of the impact shall be assessed in terms of cross-cutting criteria. This includes effects resulting from cross-sector dependencies on other types of infrastructure.

  • Event

    Occurrence or change of a particular set of circumstances.

    • An event can be one or more occurrences, and can have several causes.
    • An event can consist of something not happening.
    • An event can sometimes be referred to as an “incident” or “accident”.

  • Evolutionary Adaptation

    For a population or species, change in functional characteristics as a result of selection acting on heritable traits. The rate of evolutionary adaptation depends on factors such as the strength of selection, generation turnover time, and degree of outcrossing (as opposed to inbreeding).

  • Exposure

    The presence of people, livelihoods, species or ecosystems, environmental services and resources, infrastructure, or economic, social, or cultural assets in places that could be adversely affected

  • Fluvial Flooding

    Fluvial flooding occurs when a watercourse cannot cope with the water draining into it from the surrounding land. This can happen, for example, when heavy rain falls on an already waterlogged catchment.

  • Green Infrastructure

    Broadly defined as a strategically planned network of high quality natural and semi-natural areas with other environmental features, which is designed and managed to deliver a wide range of ecosystem services and protect biodiversity in both rural and urban settings.

    Green infrastructure may incorporate both landscape and water features, the latter of which may be termed ‘blue infrastructure’. Other terms include ‘green-blue infrastructure’ and ‘green and blue infrastructure

  • Grey Infrastructure

    Familiar urban infrastructure such as roads, sewer systems and storm drains is known as ‘grey infrastructure’. Such conventional infrastructure often uses engineered solutions typically designed for a single function.

  • Guide

    Advisory texts showing the most favourable pathways towards a goal

  • Hazard

    The potential occurrence of a natural or human-induced physical event or trend, or physical impact, that may cause loss of life, injury, or other health impacts, as well as damage and loss to property, infrastructure, livelihoods, service provision, and environmental resources.

    source of potential harm

    Note: In the context of climate change the term ‘hazard’ usually refers to climate-related physical events or trends or their physical impacts.

  • Heat Stress

    Heat stress occurs when the body’s means of controlling its internal temperature starts to fail. As well as air temperature, factors such as activity rate, humidity and clothing worn may lead to heat stress.

  • Heatwave

    A prolonged period of excessively hot weather, which may be accompanied by high humidity. There is no universal definition of a heatwave; the term is relative to the climate in the area with a locally identified threshold temperature.

  • Impact

    Effects on natural and human systems (…) the term impact is used primarily to refer to the effects on natural and human systems of extreme weather and events and of climate change. Impacts generally refer to effects on lives, livelihoods, health, ecosystems, economies, societies, cultures, services and infrastructure due to the interaction of climate changes of hazardous climate events occurring within a specific time period and the vulnerability of an exposed society or system.
    Note: Impacts are also referred to as consequences and outcomes

    The direct outcome of an event

  • Impact Chains

    Permit the structuring of cause – effect relationships between drivers and/or inhibitors affecting the vulnerability of a system.

    Impact chains allow for a visualization of interrelations and feedbacks, help to identify the key impacts, on which level they occur and allow visualising which climate signals may lead to them. They further help to clarify and/or validate the objectives and the scope of the vulnerability assessment and are a useful tool to involve stakeholders.

  • Incident

    Event that might be, or could lead to, an operational interruption, disruption, loss, emergency or crisis.

  • Incremental Adaptation

    Adaptation actions where the central aim is to maintain the essence and integrity of a system or process at a given scale.

  • Indicator

    quantitative, qualitative or binary variable that can be measured or described, in response to a defined criterion

  • Infrastructure

    Infrastructure refers to all public and private facilities which are considered to be necessary for adequate public services and economic development. In most cases, the infrastructure is divided into technical infrastructure (e.g. transport and communications facilities, energy and water supply or wastewater disposal) and social infrastructure (e.g. schools, hospitals, shopping or cultural facilities).1

    1 The definition of social infrastructure can vary as described in the social infrastructure entry which is divided into physical social infrastructure and institutional social infrastructure.

  • Inoperability

    The degree of function loss of an object

  • Likelihood

    The chance of a specific outcome occurring, where this might be estimated probabilistically. // chance of something happening

  • Mainstreaming

    Deliberate perturbation in the natural order of the things and undermines the status quo to radically expand and enhance the topic under consideration.

  • Maladaptation

    Actions that may lead to increased risk of adverse climate-related outcomes, increased vulnerability to climate change, or diminished welfare, now or in the future.

  • method

    Systematic procedure to achieve a particular result

  • Mitigation (of climate change)

    A human intervention to reduce the sources or enhance the sinks of greenhouse gases (GHGs) [and] human interventions to reduce the sources of other substances which may contribute directly or indirectly to limiting climate change, including, for example, the reduction of particulate matter emissions that can directly alter the radiation balance (e.g., black carbon) or measures that control emissions of carbon monoxide, nitrogen oxides, Volatile Organic Compounds and other pollutants that can alter the concentration of tropospheric ozone which has an indirect effect on the climate.

  • Organisation

    Person or group of people that has its own functions with responsibilities, authorities and relationships to achieve its objectives

    Note: The concept of organisation includes, but is not limited to sole-trader, company, corporation, firm, enterprise, authority, partnership, charity or institution, or part or combination thereof, whether incorporated or not, public or private.

  • Outcome Vulnerability

    Vulnerability as the end point of a sequence of analyses beginning with projections of future emission trends, moving on to the development of climate scenarios, and concluding with biophysical impact studies and the identification of adaptive options. Any residual consequences that remain after adaptation has taken place define the levels of vulnerability.

  • Passive Measure

    It is a type of measure which does not use energy once it has been implemented. It is normally refers to adaptation measures for buildings indoor environments.

  • Pluvial Flooding

    Occurs when heavy rainfall overwhelms the drainage capacity of the local area. It is difficult to predict and pinpoint, much more so than fluvial or coastal flooding. Can also be called surface water flooding.

  • Probabilistic Climate Projections

    These are projections of future absolute climate that assign a probability level to different climate outcomes. This projection provides an absolute value for the future climate (as opposed to giving values that are relative to a baseline period) that assign a probability level to different climate outcomes.

  • Recovery

    The restoration, and improvement where appropriate, of facilities, livelihoods and living conditions of disaster-affected communities, including efforts to reduce disaster risk factors

  • Reliability

    Property of consistent intended behaviour and results

  • Resilience

    1. The capacity of a social-ecological system to cope with a hazardous event or disturbance, responding or reorganizing in ways that maintain its essential function, identity, and structure, while also maintaining the capacity for adaptation, learning, and transformation (Arctic Council, 2013).

    2. The ability to function, survive, and thrive no matter what stresses happen and to skilfully prepare for, respond to, and manage a crisis. Finally, it should include the ability to return to normal operations as quickly as possible after a disruption.

    3. The ability of a system, community or society exposed to hazards to resist, absorb, accommodate to and recover from the effects of a hazard in a timely and efficient manner, including through the preservation and restoration of its essential basic structures and functions.

  • Risk

    The potential for consequences where something of value is at stake and where the outcome is uncertain, recognizing the diversity of values. Risk is often represented as probability of occurrence of hazardous events or trends multiplied by the impacts if these events or trends occur. Risk results from the interaction of vulnerability, exposure, and hazard.

    effect of uncertainty on objectives

    Note 1: An effect is a deviation from the expected. It can be positive, negative or both. An effect can arise as a result of a response, or failure to respond, to an opportunity or to a threat related to objectives..

    Note 2: Objectives can have different aspects and categories, and can be applied at different levels.

    Note 3: Risk is usually expressed in terms of risk sources, potential events, their consequences and their likelihood.

    Note 4: In the context of climate change risk is often represented as probability or likelihood of occurrence of hazardous events or trends multiplied by the impacts if these events or trends occur.

  • Scenario

    A plausible description of how the future may develop based on a coherent and internally consistent set of assumptions about key driving forces (e.g. rate of technological change, prices) and relationships.

  • Sensitivity

    The degree to which a system or species is affected, either adversely or beneficially, by climate variability or change. The effect may be direct … or indirect.

  • Social Infrastructure (Institutional)

    The social infrastructure includes the humans, organizations and governments that make decisions and form our economy as well as our institutions and policies.

  • Social Infrastructure (Physical)

    Schools, hospitals, shopping or cultural facilities

  • Stakeholder

    Person or organization that can affect, be affected by, or perceive themselves to be affected by a decision or activity

    Note: A decision maker can be a stakeholder.

  • Stressor (climate and non-climate)

    A climate stressor  is a condition, event, or trend related to climate variability and change that can exacerbate hazards. Increasing frequency and intensity of drought conditions can be a climate stressor for forests and crops. Rising sea level is another climate stressor.

    A non-climate stressor is a change or trend unrelated to climate that can exacerbate hazards. Altering drainage patterns and replacing open land with roads and buildings are non-climate stressors for flooding hazards. Population growth along exposed coasts is another non-climate stressor.

  • Uncertainty

    A state of incomplete knowledge that can result from a lack of information or from disagreement about what is known or even knowable

  • Urban (Urban Area)

    Urban ‘is a function of (1) sheer population size, (2) space (land area), (3) the ratio of population to space (density or concentration), and (4) economic and social organization.’

    The OECD-EU classification identifies functional urban areas beyond city boundaries, to reflect the economic geography of where people live and work… Defining urban areas as functional economic units can better guide the way national and city governments plan infrastructure, transportation, housing and schools, space for culture and recreation. Improved planning will

  • Urban Critical Infrastructure

    An asset, system or part thereof located in an urban area which is essential for the maintenance of vital societal functions, health, safety, security, economic or social well-being of people, and the disruption or destruction of which would have a significant impact in an urban area as a result of the failure to maintain those functions

  • Urban Critical Infrastructure

    An asset, system or part thereof located in an urban area which is essential for the maintenance of vital societal functions, health, safety, security, economic or social well-being of people, and the disruption or destruction of which would have a significant impact in an urban area as a result of the failure to maintain those functions

  • Urban Critical Infrastructure System

    Urban critical infrastructure from a systemic viewpoint. It is part of the urban system and simultaneously part of the national critical infrastructure system.

  • Urban Heat Island

    An urban heat island is a man-made area that’s significantly warmer than the surrounding countryside — especially at night.

  • Urban System

    System of urban areas (Urban settlements from a systemic viewpoint)

  • Wicked Problem

    A problem that is categorized by a great number of uncertainties. These include: on the stakeholders involved, the boundaries of the problem, long term organisational developments and responsibilities, amongst others.

    Figure 3: The RESIN Conceptual Framework

    Figure 3: The RESIN Conceptual Framework