EARLY WARNING IN SOUTHERN AFRICA:

Transcription

1 EARLY WARNING IN SOUTHERN AFRICA: Enhancing the Meteorological Early Warning System Eugene Poolman South African Weather Service

2 OUTLINE OF PRESENTATION Impact of Climate Change Meteorological Early Warning Systems in Southern Africa Challenges for Early Warning Systems

3 IMPACT OF CLIMATE CHANGE Sources: Climate Change: an Extreme Event Prof Bruce Hewitson CAMEX, 2006 World Meteorological Organization Climate Change and Sustainable Development Dr David Griggs, UK Met Office Commonwealth Conference on Disaster Mitigation, 2005

4 Climate Change is real..

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6 Why such a dramatic change? Impact of Human Activities on Natural Climate Variability Model simulations of observed global mean temperature anomalies: Only natural forcing Both natural and anthropogenic forcing

7 Increasing Impact of Natural Disasters No. reported disasters No. reported killed (thousands) Damage (US$ billion) 's 1980's 1990's

8 Global-average surface temperature projected to increase by 1.4 ºC to 5.8 ºC by 2100 under all scenarios Higher maximum temperatures, more heatwaves, dryer summers (very likely) Damage to crops, heat stress on livestock Decreased agricultural productivity, increased wildfires Water supply problems More heavy rainfall, more intense precipitation events (very likely) more river flooding, landslides, mudslides, damage to property, insurance costs Higher minimum temperatures, fewer cold extremes (very likely) extended range of pests and diseases Higher sea level (very likely) more coastal flooding

9 Impact on Africa Impact is worse on vulnerable developing countries more flood and drought prone Lower capacity to adapt Likely to impact disproportionately upon the poorest countries exacerbating inequities in health status and access to adequate food, clean water

10 Impact on Africa continued. Unprecedented events are increasing in frequency Intensity of weather events is likely to increase Africa will almost certainly warm more than global, annual mean Annual rainfall likely to decrease in North Africa Winter rainfall is projected to decrease in much of western Southern Africa Annual mean rainfall projected to increase in tropical and East Africa

11 THE METEOROLOGICAL EARLY WARNING SYSTEM IN SOUTHERN AFRICA

12 Southern Africa: Region Of Extremes Most important natural disasters in Southern Africa: Droughts, Floods, Windstorms, Epidemics

13 Weather Services aim to reduce the risk through early warning Of the 14 SADC countries, 9 are Least Developing Countries (of 49 globally) - Increased vulnerability - Reduced coping capacity Increased Disaster Risk World map indicating: High, Medium, and Low Human Development Index, 2003

14 The Role of Early Warning Systems (EWS) Approximately 80% of natural disasters worldwide are weather related The objective of early warning: to empower threatened communities to act in sufficient time and manner to reduce loss of life and damage to property.. (ISDR) According to the Secretary General of the WMO: Timely and accurate forecasts and warnings of natural hazards coupled with adequate local preparedness planning are fundamental requirements for disaster reduction Optimal response to natural disasters requires effective coordination and cooperation between responsible agencies, institutions, officials, the media

15 Principles for the application of EWS (ISDR) To be effective, EWS should be components of a broader programme of national hazard mitigation and vulnerability reduction Within each country, the sole responsibility for issuing early warnings should rest with an agency(s) designated by Government Warning-language, derived from technical information, must be understandable and relevant A considerable responsibility at local levels to communicate warnings received to those at risk in detail, and for facilitating community actions to prevent loss and damage Thus, an effective EWS is an end-to-end process

16 EWS in Cycle of Disaster Management (Wilhite 2005)

17 Four Components of an Early Warning System 1. Risk Knowledge 2. Warning Service 4. Response capability 3. Dissemination

18 NMHS Main Participants In EWS Key national agencies to issue early warnings Usually the single authoritative voice for early warning information Communities EWS will fail if communities are not involved in risk assessment, dissemination, preparedness and response Capacity Building! Authorities Concerned with Impact Emergency management departments, disaster management centres Responsible for declaring disasters Coordinate response and recovery activities Undertake preventative mitigation and preparedness activities Political Role Players, administrators Their support is crucial to make it work Link all participants! Keep them involved and informed

19 Effective Early Warning Systems Continued scientific developments Increase lead time, use new technology, better dissemination Involve stakeholders: Better understanding of their needs, increased ownership Capacity building Warning presentation and communication Concise, understandable and actionable Consistent and credible Must address the risk of end-users, advising on reaction Response: everyone at risk must Receive warning, believe it, react timely Verification

20 EWS in Africa All countries have a Weather Service issuing weather forecasts The process and use of warnings differ between countries, depending state of weather service and disaster management structures

21 WMO launch a Severe Weather Forecast Demonstration Project in Southern Africa Nov 2006 To develop integrated EWS in countries To test EWS in an operational environment Involve global weather centres, regional weather centres (SAWS) National weather centres (Mozambique, Zimbabwe, Tanzania, Botswana, Madagascar)

22 The South African Weather Early Warning System

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24 Systems Forecasting Productd Forecast Uncertainty Increasing the Lead-time 3-Month Season Outlook 2 Days 0 6 Hours Warnings Detail Warnings Observations NWP GCM & Ensembles -Satellite -Regional -Statistical Models -Radar -Mesoscale GCM Ensembles -Lightning -Ensembles -MOS -Weather Data -MOS

25 Systems Forecasting Productd Forecast Uncertainty Increasing the Lead-time 14 Days Month 3-Month Season 2 Days 7 Days Advisories Guidance Outlook 0 6 Hours Warnings Detail Warnings Observations NWP Ensembles GCM & Ensembles -Satellite -Radar -Lightning -Regional -Mesoscale -Ensembles -Medium range -Ensembles -MOS -Ensembles -MOS -Ensembles -MOS -Statistical Models GCM Ensembles -MOS -Weather Data -MOS

26 Technology For Early Warning

27 Warning and Advisory Coordination and Dissemination Coordination between forecasting offices Dissemination to Disaster Management The Question: How effective NDMC, do we reach the Media, local communities? DWAF Does the end-to-end warning MDMC system work optimally? RFO PDMC PDMC RFO Are we able to target the relevant flooded areas early enough? RFO NFC RFO MDMC PDMC PDMC MDMC MDMC

28 CHALLENGES TO EARLY WARNING SERVICES

29 Challenges to EWS

30 1. Monitoring and Forecasting Is there a sound scientific basis for making forecasts? Observation network of SAWS Scientific interpretation and decision making of weather forecasters == SAWS are spending a lot of money in this area Can accurate and timely warnings be generated? Warning guiding and decision making systems = SA is in need of a Flash Flood Guidance system

31 Warning On Flash Floods Too much water, too little time Current warnings for FF: heavy rain with potential for flash floods Ignore underlying hydrological conditions Need for a rainfall & hydro based FFG system at time of flood to determine basins in danger Integration with Disaster Management Centers

32 Central American Flash Flood Guidance System

33 2. Dissemination of understandable warnings to those at risk Do warnings reach those at risk? Collaboration between SAWS and Disaster Management Centres crucial Is the warnings understandable and useful that enable proper responses?

34 4. Preparedness to act, response capacity Do communities understand their risks? Do they know how to react? What are their coping capacities? The role of disaster managers on the ground is critical

35 SUMMARY There were tremendous developments in all the components of the EWS recently EWS is a crucial component in disaster management An excellent nowcast is useless if a warning was not issued timeously to communities at risk Warnings not reacted upon by end-user, are indicative of a failed EWS Form strong partnerships between all role players! Enhance EWS = flash flood warning system