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Early Warning

Early Warning System

Definition from the United Nations International Strategy for Disaster Reduction (UNISDR) - An integrated system of hazard monitoring, forecasting and prediction, disaster risk assessment, communication and preparedness activities systems and processes that enable individuals, communities, governments, businesses and others to take timely action to reduce disaster risks in advance of hazardous events.

The four key elements of the system to work effectively are:
(1) Disaster risk knowledge based on the systematic collection of data and disaster risk assessments;
(2) Detection, monitoring, analysis and forecasting of the hazards and possible consequences;
(3) Dissemination and communication, by an official source, of authoritative, timely, accurate and actionable warnings and associated information on likelihood and impact;
(4) Preparedness at all levels to respond to the warnings received.

Failure in one component or a lack of coordination across them could lead to the failure of the whole system.

Risk knowledge

Risks arise from the combination of the hazards and the vulnerabilities to hazards that are present. Assessments of risk require systematic collection and analysis of data and should take into account the dynamics and variability of hazards and vulnerabilities that arise from processes such as urbanization, rural land-use change, environmental degradation and climate change. Risk assessments and risk maps help to motivate people, prioritize early warning system needs and guide preparations for response and disaster prevention activities.
Monitoring and warning service
Warning services lie at the core of the system. They must have a sound scientific basis for predicting and forecasting and must reliably operate twenty-four hours a day. Continuous monitoring of hazard parameters and precursors is necessary to generate accurate warnings in a timely fashion. Warning services for the different hazards should be coordinated where possible to gain the benefit of shared institutional, procedural and communication networks

Dissemination and communication

Warnings must get to those at risk. For people to understand warnings, they must contain clear, useful information that enables proper responses. Regional, national and community-level communication channels and tools must be pre-identified and one authoritative voice established. The use of multiple communication channels is necessary to ensure everyone is reached and to avoid the failure of any one channel, as well as to reinforce the warning message.

Response capability

Communities must also respect the warning service and know how to react to warnings. This requires systematic education and preparedness programs led by disaster management authorities. It is essential that disaster management plans are in place and are well practiced and tested. The community should be well informed on options for safe behavior and on means to avoid damage and loss of property.
Multi-hazard early warning systems (UNISDR)

This system address several hazards and/or impacts of similar or different type in contexts where hazardous events may occur alone, simultaneously, cascading or cumulatively over time, and taking into account the potential interrelated effects. A multi-hazard early warning system with the ability to warn of one or more hazards increases the efficiency and consistency of warnings through coordinated and compatible mechanisms and capacities, involving multiple disciplines for updated and accurate hazards identification and monitoring for multiple hazards.

People Centered Early warning systems
The objective of people-centered early warning systems is to empower individuals and communities threatened by hazards to act in sufficient time and in an appropriate manner so as to reduce the possibility of personal injury, loss of life, damage to property and the environment and loss of livelihoods.

To develop early warning systems, the contribution and coordination of a wide range of individuals are required. These include:
1. Communities - particularly those most vulnerable, are central to people-centered early warning systems. Their input to system design and their ability to respond ultimately determines the extent of risk associated with natural hazards. They should be aware of the hazards and the related effects to which they are exposed and be able to take specific actions to minimize the threat of loss or damage.
2. Local Governments - usually have direct responsibilities for citizen safety and considerable knowledge of the hazards to which their communities are exposed. They must be actively involved in the design and maintenance of early warning systems and understand advisory information received to be able to advise, instruct, or engage the local population in a manner that increases their safety and reduces the possible loss of resources on which the community depends.
3. National governments - are responsible for policies and frameworks that facilitate early warning and usually also for the technical systems for preparing and issuing timely warnings. They have responsibility to ensure that warnings and related responses address all of the population, particularly the most vulnerable. They also provide support to local governments and communities to develop their operational capabilities and to translate early warning knowledge into local risk reduction practices.
4. Regional Institutions and Organizations - provide specialized knowledge and advice in support of national efforts to develop or sustain operational capabilities of countries that share a common geographical environment. Regional organizations are crucial to linking international capabilities to the particular needs of individual countries and in facilitating effective early warning practices among adjacent countries.
5. International Bodies - provide support for national early warning activities and foster the exchange of data and knowledge between individual countries. Support may include the provision of advisory information, technical cooperation and policy and organizational support necessary to ensure the development and operational capabilities of national authorities or agencies responsible for early warning practice.
6. Non-Governmental Organizations - (NGOs) including volunteers involving organizations play a critical role in raising awareness among individuals and organizations involved in early warning and in the implementation of early warning systems, particularly at the community level. In addition, they play an important advocacy role to help ensure that early warning stays on the agenda of government policy makers.
7. The private Sector - has a diverse role to play in early warning, including developing early warning capabilities in their own organizations. The media plays an important role in improving the disaster consciousness of the general population and by disseminating early warnings. In addition, the private sector has a large untapped potential to help provide skilled services in the form of technical manpower, know-how or donations (in-kind and cash) of goods or services, especially for the communication, dissemination and response elements of early warning.
8. The Science Community - has a central and critical role in providing specialized scientific and technical input to assist governments and communities in developing effective early warning systems. Their expertise is fundamental to analyzing natural hazard risks facing communities, supporting the design of scientific and systematic monitoring and warning services, supporting data exchange, translating scientific or technical information to comprehensible messages and to the dissemination of understandable warnings to those at risk.
Natural hazard monitoring and forecasting are carried out by specialized scientific agencies. At national level, government agencies, research organizations and universities are usually the main parties involved. At the international level, specialized agencies of the United Nations work extensively with relevant national agencies to coordinate the development of technical capacities for monitoring, detecting and warnings for a wide range of hazards and their impacts.

Benefits of Early warning systems:
1. Reduction in loss of life
2. Early notification of emergency system
3. Orderly disruption of social and economic facilities
4. Improved traffic control
5. Reduced public stress

Impacts of Natural disasters on regional countries;
On September 18th 2017, the powerful Hurricane Maria devastated Dominica. Early warning systems from the National Hurricane center monitored the hurricane before it intercepted the island.
On September 20th 2017, the powerful Hurricane Maria also devastated the island of Puerto Rico. Early warning systems from the National Hurricane center monitored the hurricane after it made landfall on Dominica and prior to it intercepting the island of Puerto Rico.
Hurricanes are monitored globally by a number of weather satellites operated by the United States of America. Military aircraft are flown around the storms (Hurricane Hunters) which are probed with sensors that transmit data to computers at the US National Hurricane Centre in Miami, which in turn provide forecasting and prediction of their intended paths, strengths, loads and the likely effects of their impact upon any country or region.

Examples of early warning systems

These are some of the early warning systems used in the Caribbean:
Rain and river gauges with electromechanical transducers providing signaling that are automatically transmitted to a central computer where processing is done and the appropriate response is initiated. This type of telemetry is widely used to provide early warning for flooding from river overflow and rain inundation.
Satellite tracking of weather systems which is globally transmitted in real time on weather channels and which is then rebroadcast by local television and cable service providers for early consumption and evasive action by threatened populations. This early warning system has undoubtedly saved millions of lives over the past decade or so, as death tolls from weather systems were considerably higher before its development.
The Tsunami Warning System is perhaps the most safety critical of all warning networks, as it must rapidly report any occurrence of undersea activity likely to produce tsunami at any point throughout the world in to allow sufficient time for evasive action. This utilizes state of the art digital communication technology in order to fulfill its mandate.
Satellite imagery is used to detect forest fires and unusual migration of population in some countries where this is a potential hazard. These pictures also give indications of performance of crops, which provide warning of impending famine and its associated epidemic implications. Bridge failure and Sea wall breaches are sometimes predicted or pre-empted by the use of electromechanical transducers, which use telemetry to signal creep. This warning system saves untold lives as buses and trucks with large numbers of people cross hundreds of times per day.
Human reporting of unusual or potentially dangerous situation is however the most widely used and effective early warning systems. This is so because it is driven by personal interest, understanding and prioritization of the potential dangers, where technological means may sometimes appear foreign to some cultures. This type of warning system is both formal and informal. Simple reporting to the authorities by members of the community is done daily, while Health Ministries, social and humanitarian workers, scientific projects, and other government agencies have monitoring and reporting systems, which provide the most basic and reliable type of warnings. This class of warning usually utilizes the most basic communications technology.

Good Practices in Early Warning Systems:
Philippines: December 2012 in response to typhoon Bopha
Through the introduction of new, automated rainfall and flood prediction systems as part of project “Nationwide Operational Assessment of Hazards” (NOAH), which helped to provide accurate forecasts and timely warnings, they were able to assist in the evacuation of over 167,000 persons. The number of deaths also reduced drastically from 1400 in a similar event that occurred previously to 200. The project includes dissemination through television and the Internet of real-time satellite, Doppler radar, and other weather information enabling people to see not only wind speed and location of incoming weather disturbance but also the possible amount of precipitation. Improvements in alert systems and communication with affected communities are also being achieved. This being seen as a crucial measure given that the country experiences about 20 typhoons per year (
Due to the devastating effects of past disasters such as Hurricane Flora, which caused 1200 casualties and US $ 300,000,000 in damages, Cuba saw the need for implementing effective early warning systems as a way to mitigate future disasters. Early warning systems have helped to reduce the impacts of disasters as seen in the recent Hurricane Irma which was reported to have a total of 10 casualties as compared to Flora. In updating the existing early warning system, Cuba recognized the need for a collaborative approach incorporating all key stakeholders from government officials to citizens for an effective, people-centered holistic system to be achieved. Measures adopted in this automation process include:
• The recognition of the need for a legal framework to regulate the functioning of the early warning system. Policies and agreements have been established which govern their Multi-Hazard Early Warning System (MHEWS)
• The recognition of the need for risk knowledge and conducting regularised risk assessments at both a national and local level which can then be disseminated to relevant authorities for corrective action to be undertaken. The Environment
Agency of the Ministry of Science, Technology and the Environment is responsible for utilising risk information in emergency planning and warning
• Recognition of the need for public education to aid in the overall outcomes of early warning systems. In this way, the public can be informed on measures that should be undertaken both before and after issuing an early warning, so that they are constantly prepared.
• Recognition of the need for strong partnership between the Cuban Meteorological Service, The Media and The Civil Defense
• Implementation of crucial technology needed for an effective early warning system: 8 Meteorological Radars have been established nationwide covering the entire country, 63 Municipal Radio Stations, and 15 Provincial TV stations for disseminating information which cover more than 95% of national territory and reaching most of the population.
• Establishment of a systematic process for the recognition, analysis and dissemination of Early Warning messages from Global Bodies such as the World Meteorological Organisation to the National Meteorological Centers and then relevant authorities (citizens, civil defense etc.), in a way that is simple, detailed and easily understood by any one person:

World Meteorological Organisation

The CREWS initiative:

The Climate Risk and Early Warning Systems (CREWS) initiative is an international partnership which seeks to strengthen risk information and early warning systems in vulnerable countries, and to provide financing to increase the capacity of Least Developed Countries and Small Island Developing States that are exposed to extreme climate events. Its aim is to generate effective, impact-based, multi-hazard, gender-informed early warnings by enabling countries to access additional resources from the Green Climate Fund and other sources. Partnering organisations include the World Meteorological organisation, the United (UNISDR), the Global Facility for Disaster risk Reduction (GFDRR) and the World Bank. CREWS provides a means through which countries can sustainably invest in early warning system technology and upgrading existing forecasting services and aims to mobilize US $100 million dollars by 2020. CREWS has provided funding for countries such as Niger, Fiji, Papa New Guinea, and Samoa for the improvement of operational hydro-meteorological forecasts and early warning.

Recently CREWS has embarked on a new project within the Caribbean to review the effectiveness of the current early warning systems giving the recent circumstances of the previous hurricane season which wreaked havoc in several islands in 2017. These will be led by the Caribbean Institute of Meteorology and Hydrology (CIMH) and the Caribbean Disaster Emergency Management Agency (CDEMA). A funding of US $5.5 million is said to be pipelined for the Caribbean region.

Other Useful links for Early Warning systems: (early Warning System Checklist UNISDR) (Examples of early warning systems for Biological Hazards issued by the World Health Organisation) (Assessment of MHEWS in the Caribbean)


Links CREWS initiative:

Hazard Maps         Emergency Contacts