Preliminary Survey of Early Warning Systems
Background Document in Support of the UN Secretary General Kofi Annan Report to the General Assembly
29 July 2005
Geneva, Switzerland
Contributed by
World Meteorological Organization

Overview

In response to the first phase of the Global Early Warning Survey requested by the UN Secretary General, Kofi Annan, WMO conducted a simple overview survey based on knowledge and experience of its ten WMO programmes to provide feedback into the progress report of the Secretary-General to the General Assembly in September 2005. In this report we provide our assessment of the current capabilities, major gaps and needs related to the four stages of Early Warning Systems, including i) risk identification (observation, monitoring, detecting), ii) forecasting and operational warnings, iii) warning dissemination, and iv) response at national to local levels. This assessment is provided for a number of hazards including tornados, flash floods, flood (river basin flooding), severe storms, heat waves, cold spells, tropical cyclones (hurricanes and typhoons), storm surges, locust, forest fires, droughts, mud and land slides, air pollution, dispersion of chemical spills, volcanic ash, nuclear accidents, through air and water.

WMO, as a specialized agency of the United Nations, works through the National Meteorological and Hydrological Services (NMHSs) to ensure that, among other things, issues related to effective operational early warnings for weather-, water-, and climate-related hazards are addressed effectively across political boundaries. WMO and its 187 Members, through its 10 international scientific and technical programmes, and its global network of three World Meteorological Centres (WMCs) and 40 Regional Specialized Meteorological Centres (RMSCs) — operated by NMHSs, its Global Observing System (GOS), Global Telecommunication System (GTS) and Global Data-Processing and Forecasting System (GDPFS) — provides around the clock operational capabilities, along with international and regional collaborations and coordination to support the early warning activities of the NMHSs at the national level. WMO’s GOS enables the observation and collection of weather, water and climate information from around the globe. Through this system, data are collected from 16 satellites, hundreds of ocean buoys, over 150,000 aircraft, 7,000 ship reports and nearly 10,000 land-based stations. NMHSs make and collect observations in their countries. These observations along with more than 50,000 weather reports and several thousand charts and digital products are disseminated daily through the WMO GTS, which interconnects meteorological centres around the globe. The WMO GDPFS ensures the cooperation of world, regional and national centres to process data and provide routinely countries with analyses and forecasts, including early warnings of severe events. Based on the analyses and forecasts provided by WMCs and RSMCs, NMHSs develop and provide early warnings adapted to local conditions and needs, when natural hazards threaten their country. Finally, through eight RSMCs, WMO supports its Members and international organizations to respond to large-scale trans-boundary environmental emergencies caused by major nuclear accidents, volcanic eruptions, chemical accidents, and wild fires.

The infrastructures of NMHSs undoubtedly constitute a considerable asset to the international community, in their efforts to deal with disaster response. This is because they are operational 24/7 organizations that have their government’s mandates for the issuance of around-the-clock early warnings for a wide rage of hazards related to weather and water. Significant capabilities for observing, detecting, monitoring, forecasting and issuance of early warning for these hazards have been developed within the NMHSs of the countries. However, the capabilities and resources of the NMHSs significantly vary from country to country.

There are major common gaps, particularly in developing and least developed countries in the chain of early warning system. While there is need for developing and improving sustainable technical capacity related to observing, monitoring, detecting and forecasting, and warning issuance capabilities of the National Meteorological Services, there are gaps in, i) linkages between the National Meteorological and Hydrological Services and the emergency management authorities and the media, ii) alert mechanisms from national authorities to local level, iii) availability of national to local emergency policy and preparedness plans, iv) education and public outreach programmes and other capacities that would enable the public to know how to respond to warnings. The following paragraphs provide a short summary of each hazard describing them, what the current capabilities are, and the major gaps and needs related to the different stages of Early Warning Systems.

Review of Existing Capabilities and Gaps for Early Warning for Different Hazards

Severe storms

Tornadoes, lightning, hailstorms, high wind, dust storms, waterspouts and heavy precipitation are examples of these events.

Tornados are most common in sub-tropical to mid-latitude regions, but have killed people on every continent except Antarctica. Tornadoes produce the strongest surface winds on Earth reaching 500 km/h. They can impact areas extending from meters to tens of kilometres. Tornado warning lead-times if any are very short. Detection and forecasting capabilities of tornadoes have been developed and are operational in a few developed countries like the United States, where warnings are issued with lead-times of up to 15 minutes. However, there are significant gaps in such capacities in developing and least developed countries.

Hailstorms - During severe hailstorms, hailstones can be 10 cm or more in diameter and can fall at speeds of 150 km/h or more. Hailstorms occur mostly in the mid-latitudes in heavy thunderstorms and can lay a path of destruction from a few to tens of kilometres. Warning lead-times can vary from none to a few hours, as forecasting hail is challenging owning to their localized nature. In developing and least developed countries there are major gaps along the entire chain of the early warning system.

Severe windstorms occur throughout the middle latitudes and are generally most frequent and intense during winter with gales lasting up to several days and extending to 1,000 km or more. Severe storms are observed and detected through the Global Observing System (GOS) of WMO and are communicated, through the WMO Global Telecommunication System (GTS), to 16 Regional Specialized Meteorological Centres, who develop forecasts and bulletins and disseminate to NMHSs in their region. NMHSs issue severe winter storm warnings in the country.

Sand and dust storms affect mainly desert areas and can range in size from 10’s to 1000’s of kilometres. Warning lead times are normally up to 3 days and are based on Satellite and ground observational data but these capabilities are not yet operational.

Heavy Precipitation (rain and snow) can affect areas from tens to hundreds of kilometres. Warning lead-times range from a few hours to a day. Early warning capabilities exist mostly in the developed and some developing countries but significant gaps exist in the least developed countries.

Flash floods

Flash floods are localized events, which occur as a sudden response to severe precipitation or ice melt and occur in almost all regions. Observation, monitoring and forecasting technologies exists in a few developed countries like the United States, Canada and Central Europe; however, these capabilities are inadequate in other countries.

Floods (river basin flooding)

Floods are among the most common and most devastating natural disasters and affect all regions. Technologies for observing, detecting, monitoring and forecasting of floods exist and have been demonstrated, however, these capabilities can be further enhanced through stronger integration of meteorological and hydrological forecasts. These capacities differ among countries and their National Meteorological and Hydrological Services. In countries with functioning flood warning services, dissemination of forecasts and warnings could reach to the district and sub-district levels; however, major gaps exist in reaching the community level. Within developing and least developed countries, there are gaps along the entire early warning system chain from observation to the ability to respond at the community level.

Heat waves

Heat waves are prolonged periods of extreme temperature and humidity that persist for a few days to weeks. They are most deadly in mid-latitude regions, especially urban areas. They affect all regions and can extend from hundreds of kilometres to portions of a continent. Computer weather models and Heat Health Warning Systems (HHWS) are used to forecast this hazard and provide warning lead-times of 1-3 days. Major gaps exist because short-term heat and health warnings are only issued in a limited number of cities and countries and where these capabilities are available, there is a lack of understanding of what the heat wave indices mean and what response is to be taken. Additionally, in most countries there is a lack or absence of coordination from national to local civil authorities.

Cold spells

Loss of life resulting from cold spells are greater among people aged 60 or older in regions with warmer winters, where people are less likely to have heating. Maximum temperatures of 4 to 5°C below normal resulted in more than 2500 fatalities in India in December 2002. Cold spells in Mongolia killed over 750000 cattle during the winter of 2001-2002. Cold spells are prolonged periods of extreme cold temperatures from days to weeks. Warning lead times are based on weather observations and 1-3 day forecasts. Warnings are only issued in a limited number of cities and countries.

Tropical cyclones

Tropical cyclones (also known as hurricanes and typhoons) are spawned in the warm tropical oceans with the strongest having sustained winds greater than 195 km/h and wind gusts greater than 280 km/h. Some can grow to a radius of more than 300 km before they decay, over either land or cooler water. Tropical cyclones have the potential to leave swath of destruction from strong winds and heavy rainfalls. In 1998, Hurricane Mitch struck Nicaragua, Honduras and Guatemala: 11 000 dead and widespread flooding. Through the World Meteorological Organization’s operational Global Tropical Cyclone Warning System, including an operational observing network, 6 tropical cyclone Regional Specialized Meteorological Centres (RSMCs), 5 Tropical Cyclone Warning Centres and the National Meteorological Services, tropical cyclone are observed, monitored and forecasted every day of the year, in all regions. Forecasts of severity, path and land fall are issued around the clock by the RSMCs and issued to the National Meteorological Services of countries at risk, who then issue the warning for their countries with warning lead-times of at least 24 hours. There are continued efforts to improve further the forecasting capabilities (tropical cyclone tracks, etc). While in many countries, these warnings are integrated in the emergency preparedness and response plans, significant gaps exist in the developing and least developed countries. Also, there is need for continued improvement of tropical cyclone forecasting capabilities.

Storm surges

Storm surges are experienced in all coastal regions and can affect areas from tens to hundreds of kilometres and are mostly associated with tropical cyclones. Warning lead times are at least 24 hours. Forecasting of storm surges and the associated coastal flooding are generally carried out by national meteorological and hydrological services and gaps are found in countries where their National Meteorological and Hydrological services have limited capacity. Overall, there is need for building technical capacity for forecasting of storm surge and related coastal flooding and linking this information with the emergency preparedness and response authorities, particularly in the developing and least-developed countries. Bangladesh serves as another excellent example in its decade-long effort to establish integrated early warning services to safeguard its population from hazards as a result of tropical cyclones, storm surges, tidal and riverine floods. It is mainly due to the largely successful implementation of improved observational and communication systems, close cooperation between the NMHSs, development of nationwide alert mechanisms built on a network of over 5,000 volunteers and other alert mechanisms to deliver critical warnings and advisories to communities at-risk. This mechanism combined with culturally-based educational and preparedness programmes and emergency planning activities such as building of shelters in the coastal areas have proven to be highly effective in saving many lives.

Locust

Locust swarms are normally experienced in the regions of Saharan and Sub-Saharan Africa, South West Asia, and regions of Australia. General Warning bulletins and advisories are produced mainly through National Locust Control Centres and only a few National Meteorological Services are involved in their dissemination. Warning lead times are on the order of less than a month for an initial outbreak to 3 to 6 months in a plague. Potential for locust swarms are anticipated through detection of their food sources via utilization of satellite and ground based observations. Warning capabilities can be improved if these capabilities are linked to operational weather forecasts. However, there are significant gaps for the developing and least developed countries as there is need to build technical capacity within the National Meteorological Services to be able to link and provide these capabilities to the National Locust Centres. Other gaps include integration of warnings with prevention strategies to take appropriate control measures to reduce the swarms. Finally, since locust swarms are major regional issue, enhanced regional coordination can help in reducing the risk of locust swarms across national boundaries.

Forest fires

All regions experience forest fires and the devastation can extend from a few to thousands of kilometres in size. Warnings are based upon a fire weather index or fire danger rating and lead-times for the highest fire danger are normally 4-6 hours, however, using forecasted weather data, as much as 14 days of early warning can be provided. Warning lead-times are based on meteorological monitoring and forecasting along with satellite imagery and ground based WMO GAW aerosol measurements. Numerous early warning systems for wild land fire are currently in operation; however no internationally accepted system exists. Within the least developed countries, there are major gaps along the entire early warning system chain from observation to the ability to respond at the community level.

Droughts

Droughts can be experienced in all regions and can affect areas from tens to thousands of kilometres and can persist for months to years. The primary cause is deficiency of rainfall and timing, distribution, and intensity of this deficiency in relation to existing reserves, demand and water use. Temperature and evaporation may aggravate the severity and duration. Early warning capabilities can range from a few weeks to several months and are based upon current observations that are integrated with meteorological forecasts. Most National Meteorological and Hydrological Services monitor drought and or produce some kind of drought index but collaboration varies by country. Bulletins and advisories are only starting to be issued mainly by the developed countries. At the national and local level, only a few countries have drought plans that integrate drought monitoring with policy actions.

Mud and landslides

Heavy rain or snowmelt often triggers mudflows and landslides, and steep terrain is usually involved. Landslides send large amounts of earth, rock, sand or mud flowing swiftly down mountainsides, especially those denuded by wild land fires. Mudflows are essentially super wet, fast-moving landslides. The resulting river of mud, reaching 50 km/h or more, accumulates and hurls trees, boulders, other massive debris that crushes with tremendous impact. Worst natural disaster ever in Venezuela occurred in 1999 where landslides and mudflows shot down Avila Mountain, washing away towns, killing an estimated 15,000 to 20,000 people, and resulting in almost US$ 2 billion in damages. Early warning capacities exist only in a few developed countries where warning lead-times range from none to a few hours.

Chemical spill dispersion

All regions can be affected by chemical spills. They are experienced mainly in the vicinity of industrial transportation corridors and can extend from local to hundreds of kilometres. Warning lead times are from minutes to hours and are based on observational data, satellite imagery and meteorological and oceanographic forecasts. Capabilities in observation, monitoring, forecasting, and dissemination vary by country but major gaps are found in the least developed countries.

Volcanic ash dispersion

Volcanic ash is experienced mainly in the mountainous volcanic regions but can affect large areas on the order of hundreds to thousands of kilometres. Warning lead times are generally tens of minutes to hours and are based on observational and forecast data. Through the global network of volcano observatories, which is coordinated by the World Organization of the Volcano Observatories, only a small percent of the 500 known active volcanoes are monitored, and not all continuously. A number of ground-based, airborne, and space based observation of volcanic ash cloud are used by WMO Members but their number and frequency need to be enhanced and new sensors need to be developed.