Tsunami occurring prior to the historical record or for which there are no written observations. Paleotsunami research is based primarily on the identification, mapping, and dating of tsunami deposits found in coastal areas, and their correlation with similar sediments found elsewhere locally, regionally, or across ocean basins. As work in this field continues it may provide important new information about past tsunamis to aid in the assessment of the tsunami hazard.


Occurs when decision-making and development activities are participatory.


The quality of an approach to development and/or government in which the underlying principle is that the key stakeholders (and especially the proposed beneficiaries) of a policy or intervention are closely involved in the process of identifying problems and priorities and have considerable control over the related activities of analysis, planning and the implementation of solutions. To facilitate this approach there are a variety of participatory methods or techniques that can be used.

Participatory Activitiessee participatory.


Participatory Developmentsee participatory.


Participatory Methods

These are methods that are used to encourage people’s participation in the processes of identifying/analyzing livelihood opportunities and problems, setting priorities and planning, implementing solutions, and monitoring and evaluating changes and impacts. They are very important for understanding livelihoods and are designed so as to promote learning and empower people in their dealings with external agencies and institutions.

PartnershipsRefers, in the SL Approach, to Partnerships in the development process.


Passenger Liner

Very large ships built to transport lots of people. They have many bedrooms (cabins) and eating areas. They are like floating hotels.

Patch Reef

 A mound like or flat-topped organic reef, generally less than 1 km across, frequently forming part of a larger reef complex


 Dark-brown to black, fibrous material produced by plants which grow in marshes or bogs. When exposed on the beach face, it indicates long-term erosion and landward barrier migration.


Rounded lumps of rock. These were broken off the cliff and made round by the waves rolling them up and down the beach.


capable of living any place from top to bottom in the oceanic water column; not restricted to living at the bottom.

People centered

Sustainable poverty elimination will be achieved only if external support focuses on what matters to people, understands the differences between groups of people and works with them in a way that fits in with their current livelihood strategies, social environment and ability to adapt.
Perched Beach - Beach or fillet of sand retained above the otherwise normal profile level by a submerged dike or sill.

Perched Beach

 A beach or fillet of sand retained above the otherwise normal profile level by a submerged dike

Photic Zone

The zone extending downward from the ocean surface within which the light is sufficient to sustain photosynthesis. The depth of this layer varies with water clarity, time of year and cloud clover, but is about 100m in the open ocean.It may be considered the depth to which all light is filtered out except for about one percent and may be calculated as about two and a half-times the depth of a secchi disk reading.


 The science of deducing the physical dimensions of objects from measurements on images (usually photographs) of the objects


An assemblage of photographs, each of which shows part of a region, put together in such a way that each point in the region appears once and only once in the assemblage, and scale variation is minimized


A vertical structure that support the spans of a bridge. Pier structures are sometimes referred to as jetties.
Pile - Long, heavy section of timber, concrete or metal driven or jetted into the earth or seabed as support or protection.
Pile, Sheet - Pile with a generally slender, flat cross section driven into the ground or seabed and meshed or interlocked with like members to form a diaphragm, wall, or bulkhead.

Plunge Point

For a plunging wave, the point at which the wave curls over and falls.The final breaking point of the waves just before they rush up on the beach

Pocket beach

A beach located between two headlands

Point source pollution

pollution that is discharged from a fixed location such as the end of a pipe.


One of the components of Policy, Institutions and Processes (PIPs), Policy can be thought of as a course or principle of action designed to achieve particular goals or targets. These tend to be broader and less specific than those of the programmes and projects used to implement Policy.


A contaminant that in a certain concentration or amount will adversely alter the physical, chemical, or biological properties of the environment-includes pathogens, heavy metals, carcinogens, oxygen-demanding materials, and all other harmful substances, including dredged spoil, solid waste, incinerator residue, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, and industrial, municipal, and agricultural wastes discharged into coastal waters.


Polluter pays principle

Political/economic principle stating that polluters should pay the full environmental costs of an activity. Some experts extend the principle to state that users that should pay the full social costs of an activity, but this is not universally accepted.

Polluter-pays Principle

 The principle adopted by the OECD countries in 1972, requires that the polluter should bear the costs that pollution damage or pollution control impose upon society


The man-made or man-induced alteration of the chemical, physical, biological, or radiological integrity of an aquatic ecosystem.

POPs(persistent organic pollutants)

 A diverse group of chemicals that persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effects to human health and the environment. A group of twelve POPs (the "dirty dozen") have been initially selected for international action by the International Programme on Chemical Safety (IPCS).


A coastal town where ships and boats come and go.

Post project evaluation

A procedure to review the performance of a project with respect to its original objectives and the manner in which the project was carried out.
potentially active beach.

Precautionary approach

 The essence of the approach is expressed in Principle 15 of the Rio Declaration that states "Where there are threats of serious or irreversible damage, lack of scientific certainty shall not be used as a reason to postponing cost-effective measures to prevent environmental degradation." The approach is concerned with avoiding risk that has not been assessed, i.e. uncertainty

Present value PV

The value of a stream of benefits or costs when discounted back to the present time.

Primary productionThe amount of plant life produced in a given area or environment


Primary waste treatment

A process that removes material that floats or will settle in sewage, accomplished by using screens to catch the floating objects and settling tanks for heavy matter, and often including chlorination; removes of about 30% of BOD and less than half of metals and toxic organics.



The likelihood of some event occurring.

Problem formulation

The first phase of ecological risk assessment, which includes a preliminary description of exposure and ecological effects, scientific data and data needs, key factors to be considered, and the scope and objectives of the assessment. This phase produces the risk hypotheses, conceptual model and analysis plan, around which the rest of the assessment develops.

Process approach

An approach to interventions in which broad objectives for change may be identified and agreed but the exact means by which these objectives will be achieved may, at the outset, be unknown and unknowable. Such interventions are approached in an exploratory mode. Implementation takes place in successive, defined, iterative stages with future activities being planned in the light of results gained as implementation proceeds.



One of the components of Policy, Institutions and Processes (PIPs). ‘Processes’ attempts to capture the dynamic element of policies and institutions and avoid a ‘snapshot’ approach. It refers to how things are done rather than what is done. It also refers to the ways policies and institutions change and/or interact with broader processes of change.


A programme is a set of activities designed to achieve a specific purpose. The term may describe a mix of projects, training and capacity building, budgetary support and policy dialogue. A programme may focus on a region – such as southern Africa –, a country, or an area within a country. It may be multi-sectoral or focus on a single sector.

Project Scope

The range of activities and issues addressed by a project.

Protected area

a natural area of land or water set aside by governmental action, as a right of ownership, to protect its resources from degradation.