Predicting Impacts of Cyclones in South-East Africa (PICSEA)

Lead Research Organisation: University of Reading
Department Name: National Centre for Atmospheric Science

Abstract

On average, 14 tropical cyclones per year form in the southern Indian Ocean, most in the months between November and April. Of these, about 2-3 cyclones per year make landfall in southeast Africa, most often in Mozambique and Madagascar. In these countries, tropical cyclones are associated with approximately one-third of all extreme daily precipitation events, defined as days with rainfall accumulations greater than 50 mm (2 inches). Tropical cyclone landfalls in Mozambique in 2012 caused severe flooding, resulting in US$65 million in damage and 150 deaths. Two cyclone landfalls in Madagascar in early 2018 resulted in 23 deaths and displaced 21,000. The Seychelles archipelago is also affected by tropical cyclones, including category 5 (the most severe) Fantala in 2016.

Despite the vulnerability of the southeast African population to tropical cyclones and related hazards, little is known about the ability of contemporary weather and climate prediction systems to forecast cyclone tracks, intensities, and wind and rain impacts. Further, there may be particular tropical atmospheric circulation patterns that provide "windows of opportunity" for more accurate cyclone forecasts. For instance, El Nino conditions (warm equatorial Pacific Ocean temperatures) may provide the backdrop for more accurate predictions of tropical cyclones and their impacts.

The "Predicting Impacts of Cyclones in South-East Asia" (PICSEA) project addresses these shortcomings by providing the most comprehensive assessment of forecast systems to date for tropical cyclones and their effects on southeast Africa. This assessment is needed desperately to give advice to national meteorological agencies, humanitarian organisations and the growing forecast-based finance community on how best to interpret forecasts of tropical cyclones in the southern Indian Ocean. Specifically, PICSEA will determine which forecast systems, lead times and background tropical circulations lead to relatively more or less accurate tropical cyclone predictions. When should disaster management agencies trust a forecast for a landfalling tropical cyclone, and when should they not?

Initially, PICSEA will assess the accuracy of predictions of tropical cyclone tracks, intensities and associated hazards (primarily wind and rain) from three weather forecasting centres: the UK Met Office, the European Centre for Medium-range Weather Forecasts and the US National Centers for Environmental Prediction. We have 10-30 years of forecast data for each centre, including multiple realisations of each forecast. We will determine to what extent, and how far in advance, contemporary prediction systems can forecast the extreme winds and rainfall associated with tropical cyclones in southeast Africa.

Next, PICSEA will determine whether there are particular background tropical conditions, such as El Nino or La Nina, that lead to more or less accurate forecasts. We will do this by evaluating forecast accuracy conditioned on the type of background conditions. Is skill for cyclone-related hazards greater during La Nina or El Nino? Are there particular circumstances under which forecasters and disaster-management agencies should trust these forecasts more, or less?

Finally, PICSEA will work together with partner organisations -- national meteorological organisations in Mozambique, Madagascar and the Seychelles, as well as the Red Cross / Red Crescent Climate Center, a key provider of scientific advice to humanitarian organisations and the forecast-based finance community -- to develop guidance for interpreting tropical cyclone forecasts. We will work with forecasters and disaster-management agencies to improve their understanding of when they can, and cannot, trust forecast information on cyclone impacts. PICSEA will also provide training in the use of this guidance, as well as background training on tropical meteorology, for forecasters in southeast African meteorological agencies.

Planned Impact

The "Predicting Impacts of Cyclones in South-East Asia" (PICSEA) project will benefit national meteorological agencies in southeast Africa, the United Kingdom, Europe and the US; humanitarian organisations, particularly those engaged in forecast-based finance initiatives; national governments in southeast Africa; and the general population of southeast Africa.

PICSEA will provide the most comprehensive analysis to date of prediction skill for South Indian Ocean tropical cyclones, particularly for the extreme wind and rainfall hazards associated with landfalling cyclones in southeast Africa. PICSEA will assess short-range numerical weather predictions (up to 14 days ahead) for individual cyclones, as well as seasonal predictions (up to six months ahead) for basin-wide activity in the South Indian Ocean. This assessment will benefit national meteorological agencies in southeast Africa, who currently lack information on how far in advance they can trust predictions of cyclones and their associated wind and rain hazards. PICSEA will also determine whether there are "windows of opportunity" for more skilful prediction - large-scale atmospheric conditions under which certain forecast models perform more accurately than they do on average. Combined with our overall skill assessment above, identifying these windows will allow national meteorological agencies to understand when they can and cannot trust predictions of the track and intensity of cyclones, as well their wind and rainfall extremes.

This improved understanding will translate directly into more accurate warnings of landfalling tropical cyclones, issued further in advance. These improved warnings will benefit disaster management agencies in national governments in the region, who will be able to mobilise resources further in advance of impending tropical cyclone landfalls. More accurate warnings will also reduce false-alarm rates, which will contribute to greater public trust in warnings and hence to a more robust public response to warnings and evacuation orders.

National meteorological agencies in the US, Europe and the UK will benefit from our assessment of their forecast systems for South Indian Ocean tropical cyclones and their impacts. Prediction skill for cyclone activity in the South Indian Ocean is subject to far less scrutiny than activity in other basins, such as the North Atlantic and West Pacific. No study has compared the performance of contemporary models for cyclone rain and wind hazards in the South Indian Ocean, or investigated how large-scale atmospheric variability affects prediction skill. PICSEA will provide this comprehensive assessment to inform modelling centres of the atmospheric circumstances under which their systems have relatively more or less skill than those of other centres. We will report these findings through papers and international initiatives, and thus contribute to pathways for model improvements.

We will collect our scientific results on forecast skill into a set of guidelines for interpreting cyclone forecasts, developed in collaboration with national meteorological agencies and humanitarian organisations involved in forecast-based financing. These guidelines will inform the development of standard operating procedures (SOPs) for forecast-based finance, which seeks to release funding for humanitarian assistance in advance of weather-related disasters. By informing humanitarian organisations of the models, forecast lead times and atmospheric circulations when forecasts are more or less accurate, PICSEA will contribute to the design and implementation of successful forecast-based financing activities in southeast Africa.

The general public of southeast Africa will benefit from PICSEA through improved warnings of cyclone impacts, improved disaster response efforts, as well as from forecast-based finance activities that will allow humanitarian aid to be marshalled further in advance of cyclone landfalls.

Publications

10 25 50
 
Description Collaboration with DFID on Cyclone & Flood Forecasting
Geographic Reach Africa 
Policy Influence Type Implementation circular/rapid advice/letter to e.g. Ministry of Health
Impact In March 2019, the UK Department for International Development requested our help in providing emergency real-time flood forecasts for two devastating tropical cyclones in Mozambique. We provided rapid advice to DFID alongside weather & flood forecast information, which was provided to DFID and disseminated to humanitarian organisations and to the UN Office for the Coordination of Humanitarian Affairs, who included the information in their daily situation reports, which are read by humanitarians and governments worldwide. The work helped in humanitarian decision-making and response in Mozambique and feedback is that the information was invaluable in responding to these disasters. Both DFID and the UN are interested in PICSEA's research outcomes, and DFID are exploring how this work could be operationalised for future events.
 
Title Tropical Cyclone Tracks - Southern Hemisphere 
Description Database of southern hemisphere tropical cyclone tracks in ECMWF operational analysis data, 2006-2019 Database of southern hemisphere tropical cyclone tracks in UKMO HRES forecast data, 2006 - 2019 Database of southern hemisphere tropical cyclone tracks in ECMWF HRES & ENS forecast data, 2013 - 2019 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? No  
Impact These tropical cyclone track data for the southern hemisphere are essential for PICSEA research, but will also be valuable datasets for our project partners at the national weather services in Mozambique, Madagascar and the Seychelles, and for future research projects. Production of the data is ongoing. 
 
Description Collaboration on Flood Forecasting for Cyclones in Mozambique 
Organisation European Centre for Medium Range Weather Forecasting ECMWF
Country United Kingdom 
Sector Public 
PI Contribution During tropical cyclones Idai and Kenneth in Mozambique in 2019, the PICSEA research team collaborated with the above organisations, after a request from DFID, to provide emergency flood forecasts for the two cyclones in real-time. We interpreted cyclone and flood forecasts to provide expert interpretation of the potential flood impact and risk. Following this, the PICSEA research team led a research paper in collaboration with the above organisations, discussing this work and evaluating the forecasts.
Collaborator Contribution Other partners in this collaboration provided flood forecasts and model developers' expertise (ECMWF), flood inundation modelling (University of Bristol) and coordination of the bulletins and dissemination (DFID) to high-level organisations (UN OCHA) and humanitarian organisations. All partners have contributed analysis and discussion to the resulting research paper.
Impact Outputs: real-time flood forecast bulletins which contributed to humanitarian decision-making, research paper This collaboration is multi-disciplinary, including partners from the natural sciences (meteorology, hydrology), social sciences, humanitarian organisations and government/policy.
Start Year 2019
 
Description Collaboration on Flood Forecasting for Cyclones in Mozambique 
Organisation Government of the UK
Department Department for International Development (DfID)
Country United Kingdom 
Sector Public 
PI Contribution During tropical cyclones Idai and Kenneth in Mozambique in 2019, the PICSEA research team collaborated with the above organisations, after a request from DFID, to provide emergency flood forecasts for the two cyclones in real-time. We interpreted cyclone and flood forecasts to provide expert interpretation of the potential flood impact and risk. Following this, the PICSEA research team led a research paper in collaboration with the above organisations, discussing this work and evaluating the forecasts.
Collaborator Contribution Other partners in this collaboration provided flood forecasts and model developers' expertise (ECMWF), flood inundation modelling (University of Bristol) and coordination of the bulletins and dissemination (DFID) to high-level organisations (UN OCHA) and humanitarian organisations. All partners have contributed analysis and discussion to the resulting research paper.
Impact Outputs: real-time flood forecast bulletins which contributed to humanitarian decision-making, research paper This collaboration is multi-disciplinary, including partners from the natural sciences (meteorology, hydrology), social sciences, humanitarian organisations and government/policy.
Start Year 2019
 
Description Collaboration on Flood Forecasting for Cyclones in Mozambique 
Organisation University of Bristol
Country United Kingdom 
Sector Academic/University 
PI Contribution During tropical cyclones Idai and Kenneth in Mozambique in 2019, the PICSEA research team collaborated with the above organisations, after a request from DFID, to provide emergency flood forecasts for the two cyclones in real-time. We interpreted cyclone and flood forecasts to provide expert interpretation of the potential flood impact and risk. Following this, the PICSEA research team led a research paper in collaboration with the above organisations, discussing this work and evaluating the forecasts.
Collaborator Contribution Other partners in this collaboration provided flood forecasts and model developers' expertise (ECMWF), flood inundation modelling (University of Bristol) and coordination of the bulletins and dissemination (DFID) to high-level organisations (UN OCHA) and humanitarian organisations. All partners have contributed analysis and discussion to the resulting research paper.
Impact Outputs: real-time flood forecast bulletins which contributed to humanitarian decision-making, research paper This collaboration is multi-disciplinary, including partners from the natural sciences (meteorology, hydrology), social sciences, humanitarian organisations and government/policy.
Start Year 2019
 
Description Collaboration on Flood Forecasting for Cyclones in Mozambique 
Organisation University of Oxford
Country United Kingdom 
Sector Academic/University 
PI Contribution During tropical cyclones Idai and Kenneth in Mozambique in 2019, the PICSEA research team collaborated with the above organisations, after a request from DFID, to provide emergency flood forecasts for the two cyclones in real-time. We interpreted cyclone and flood forecasts to provide expert interpretation of the potential flood impact and risk. Following this, the PICSEA research team led a research paper in collaboration with the above organisations, discussing this work and evaluating the forecasts.
Collaborator Contribution Other partners in this collaboration provided flood forecasts and model developers' expertise (ECMWF), flood inundation modelling (University of Bristol) and coordination of the bulletins and dissemination (DFID) to high-level organisations (UN OCHA) and humanitarian organisations. All partners have contributed analysis and discussion to the resulting research paper.
Impact Outputs: real-time flood forecast bulletins which contributed to humanitarian decision-making, research paper This collaboration is multi-disciplinary, including partners from the natural sciences (meteorology, hydrology), social sciences, humanitarian organisations and government/policy.
Start Year 2019
 
Description Collaboration with ECMWF 
Organisation European Centre for Medium Range Weather Forecasting ECMWF
Country United Kingdom 
Sector Public 
PI Contribution Collaboration with ECMWF has spanned two awards; beginning with Rebecca Emerton's PhD research in collaboration with ECMWF, and continuing during the PICSEA project as a visiting scientist. The research from both awards contributes to the research interests of ECMWF, and Rebecca has helped to run various workshops and events at ECMWF sicne 2014, alongside contributing to scientific publications written by colleagues at ECMWF, and vice versa. During PhD research, led the development of a new component of the Global Flood Awareness System.
Collaborator Contribution ECMWF provide access to their supercomputing facilities and extensive data archives alongside the expertise of model developers and researchers at ECMWF. Colleagues at ECMWF have contributed to PICSEA research publications. During PhD research, colleagues at ECMWF provided key training on the use of the Global Flood Awareness System and development of flood forecasting models, alongside knowledge of how these systems are used across Europe and the globe. Colleagues at ECMWF contributed towards research publications associated with this award. From 2014-2018, Rebecca was also provided with a full-time desk and computer at ECMWF in order to make use of the computing facilities available there.
Impact ERA-20C 1901-2010 global 10-member river discharge reanalysis dataset. ERA-Interim 1980-present global river discharge reanalysis dataset. Various engagement activities and workshops such as the Flood Hack GloFAS hackathon. Co-authorship of several research publications. ECMWF are directly aware of ongoing research under the PICSEA project, evaluating their tropical cyclone forecasts.
Start Year 2014
 
Description Mozambique National Meteorological Service 
Organisation Meteorological Research Institute
Country Japan 
Sector Public 
PI Contribution We are collaborating with INAM (Mozambique National Meteorological Service) to provide expertise and advice on tropical cyclone forecasting for the South Indian Ocean. This includes training of INAM staff and a visiting scientist placement at the University of Reading for an INAM researcher.
Collaborator Contribution INAM have contributed their expertise in regional weather patterns, local weather forecasting and rainfall observations. We are using the latter in collaboration with INAM to evaluate forecasts of tropical cyclone rainfall, which often leads to severe flood hazards in Mozambique.
Impact No outputs yet
Start Year 2018
 
Description Media Enquiries & Radio Interviews 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact Various media interviews and responses to media enquiries, including radio interviews with BBC Radio 5 Live and BBC World Service and a fact-finding interview with NPR alongside written responses to media enquiries in the UK (The Guardian, BBC Environment) and internationally (NPR, Pravda Slovakia). These were in relation to Cyclones Idai and Kenneth in Mozambique in March and April 2019, and further interest in tropical cyclone forecasting and climate change.
Year(s) Of Engagement Activity 2019,2020
URL https://www.theguardian.com/world/2019/mar/19/climate-change-making-storms-like-idai-more-severe-say...
 
Description PICSEA Workshop & Advisory Board Meeting 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact The PICSEA research team organised and hosted a 2-day workshop on tropical cyclone research at the University of Reading. Participants attended from various UK and international institutions, including the University of Reading, UK Met Office, European Centre for Medium-Range Weather Forecasts, Department for International Development, and PICSEA project partners from the Mozambique, Seychelles and Madagascar meteorological services and Red Cross Climate Centre. This was followed by a PICSEA advisory board meeting with the PICSEA research team and project partners.
Year(s) Of Engagement Activity 2020
 
Description Tropical Cyclone Discussion Meeting 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Other audiences
Results and Impact In September 2019, PICSEA, in collaboration with the SHEAR project FATHUM, hosted a tropical cyclone discussion meeting in Maputo, Mozambique. In attendance were directors from the Mozambique national weather service, national hydrological service, national disaster management institute, Technical University and regional hydrological services. The purpose was to discuss the forecasting, decision-making and impacts surrounding cyclones Idai and Kenneth, and cyclones more generally, in Mozambique, and discuss how to strengthen existing collaborations and build new collaborations towards improved cyclone forecasting and response.
Year(s) Of Engagement Activity 2019