Professor Willem Landman (University of Pretoria) - Principle Investigator

Dr Nkanyiso Mbatha (University of Zululand)

Prof Hector Chikoore (North West University)

Prof Jennifer Fitchett (University of the Witwatersrand)

Dr Joel Botai (South African Weather Bureau)

Dr Neville Sweijd (Alliance for Collaboration on Climate & Earth Systems Science)

1.      Science content

Extreme climate events (ECEs) take the form of defined exceedances of various climate parameters relative to climatological averages of the annual climate cycle (heat/cold, drought/floods, wind). Impacts of ECEs vary with geographical and temporal scale and intensity. The exceedances of these parameters, in isolation or combination, can cause natural disasters which have devastating impacts in all sectors of the economy and society – including health, agriculture, infrastructure and logistics. The intensification of ECEs is projected to proceed with climate change. Thus their frequency, duration, amplitude (power), geographical scale, temporal occurrence (aseasonal events) and duration will continue to trend. The impact may manifest in increased frequency and scales of wildfire direct (hail, wind and drought) and indirect (disease and pest outbreaks) damage to crops, increased (or decreased) incidence of infectious disease, and disruption to economic activity (e.g. port operations). This project will establish a new trans-institutional and multi-disciplinary research consortium to make a contribution to evidence-based climate services.  Scientifically the research will test the hypothesis that there is a statistically observable intensification of ECEs in South Africa and will commence with a modest set of four case studies, to standardise the approach to assessment of ECEs in real-world settings with actionable outputs.

 2.      Relevance and impact

ECEs have become a prominent feature of life in South Africa. Recent events such as the Cape Town Table mountain fire, the southern Cape Floods, The Knysna Fire, the Western Cape, Northern Cape and Eastern Cape droughts, flooding in Limpopo, the malaria surge in 2017 and many others illustrate the devastating impact these can have on life and limb. While some disparate and sectoral efforts are underway to address early warning and long term trends in these ECE effects, a holistic, standardised, unified and formally institutionalised system for the scientific evidence base for management of ECEs is still lacking. Global warming and climate change science projects that the intensity of these ECEs will increase in time, and evidence exists that this is already taking place. Given that South Africa has developed a Climate Change National Adaptation plan, and is implementing a National Climate Services Framework, this project lays a foundation for developing best science practice for assessing, predicting and projecting the trajectory of trends of ECEs in South Africa. Working with key national agencies such as the MRC, ARC, SAWS, CSIR and the DRMC, the project will ensure that the outputs are properly institutionalized for optimal outcomes.

3.      Human Capacity Development

There are three aspects to the strategy for HCD is this project. Firstly the project will ensure that the expertise available to this large consortium are used across the project by dedicating one work package to training and HCD (WP1 – toolbox). This will provide the entire team, including those working in the respective agencies (ARC, MRC and SAWS) with targeted capacity development.  Secondly, this project seeks to provide emerging researchers, black researchers and female researchers with opportunities to play a leadership role in the project. Hence 4 of the 6 of our management team comprises researchers from these categories. We have also made an effort to recruit emerging researchers to the consortium, and so the project will ensure that there is a healthy mix of experienced researchers working closely with less experienced researchers. The third element of the capacity building is then the more traditional means of HCD which is the recruitment and qualification of research students into the project (we envisage 4 PhDs and 8 Masters students) from this work. It is also necessary to note that the project is also designed to be interdisciplinary in the need to research the social and economic impacts of ECEs.

 4.      Science content

4.1 Problem statement / introduction  

Climate parameters including heat, precipitation, wind, and humidity, vary in space and time, and within climatologic limits. Parameter exceedances beyond the climatological thresholds, periodically lead to extreme weather conditions. These conditions can themselves facilitate  and exacerbate natural disasters such as fires, flooding, droughts, and other forms of weather related disruptions. Conceptually, an exceedance of a one or a combination climate parameters together with its impact on human and/or natural systems, is referred to as an Extreme Climate Event (ECE).

ECEs are by definition rare and unpredictable climate phenomena, classified by meteorological characteristics and socio-economic consequences (Stott et al., 2016). A growing body of literature on a range of ECEs is emerging both globally and locally, tracking their spatial distribution, frequency and intensity. Central to this is on-going discourse regarding the definitions of ECEs (McPhillips et al., 2018). For drought, the distinction between dry conditions and drought is crucial in delineating the event from the seasonal normal and interannual variation, and a key component of the WMO Lincoln Declaration on Drought (Fitchett, 2019). For extreme temperature events, definitions of temperature, heat and physiological heat stress are important. For tropical cyclones, regional terminology (Hurricanes, Typhoons, Cyclones), and thresholds differentiating tropical storms from cyclones are important in regional comparison. To classify and quantify ECEs, both as climatological phenomena and as drivers of socio-economic disasters, there have also been considerable efforts towards the development and refinement of indices. For example, the WMO Commission for Climatology and Indices Expert team on Sector-Specific Climate Indices ET-SCI has developed ClimPACT2 software, for the calculation of a range of indices for ECEs (Alexander et al., 2017). Individual event-specific indices, such as the SPEI for drought in agricultural settings have been developed in parallel to these, and continue to be used (Begueria et al., 2014). More simplistic definitions of percentile exceedances are also still employed, with continued engagement regarding the thresholds which would constitute an ECE (Easterling et al., 2000). A challenge with this approach is that while a technical definition of an ECE has value, often climate parameter variability approaching these thresholds, but not exceeding them, may have impacts which are just as devastating. Hence it is important to be able to adapt definitions of an ECE to its context. For example, although standard definitions of heat waves exist, it is known that sub-event extremely hot days can have significant impacts on health.

Climate change has heightened the urgency of this research, increasing the variability, power, and frequency of ECEs (Diffenbaugh et al., 2017). Analyses of trends in ECEs in South Africa reveal increases in both hot and cold extreme temperature events, the intensity and poleward displacement of tropical cyclones, and the incidence of intense and prolonged drought events (Wright et al. 2021). Within the past five years alone, the region has experienced the Day Zero drought in Cape Town (Sousa et al., 2018), the 2017 drought in the Kruger National Park (Malherbe et al., 2020), and ongoing drought conditions in the Eastern Cape Province (Mahlalela et al., 2020). Tropical Cyclone Dineo, Idai and Eloise have induced flooding in northern and northeastern South Africa (Bopape et al., 2021). Record high winter temperatures in the Eastern Cape and record high maximum temperatures in Cape Town were both recorded in 2019 (van der Walt and Fitchett, 2021). Coupled heat and dry conditions are among factors driving an increase in fire events (Abatzoglou et al., 2019; Goss et al., 2020) with some notable examples in South Africa (e.g. the Knysna fire of 2017) . These ECEs, as individual events, and characteristic of an evolving climate system of “presses and pulses'', are detrimental to human health (Wright et al., 2021), and have significant impacts on natural ecosystems (Harris et al., 2018), agriculture (Cogato et al, 2019), and logistics (Doll et al., 2014).

Despite the heightened awareness regarding ECEs and the development of sector-specific indices, little research has been conducted on the specific impacts of the incidence of ECEs on the agriculture, health, logistics and land use sectors in South Africa. Indeed, where research has explored the ECE as a climatological system, sectoral impacts are mentioned in passing (eg. Sousa et al., 2018; Bopape et al., 2021; van der Walt and Fitchett, 2021). This is in part due to the absence of a tool box for the identification, classification and quantification of not only the ECE, but the coupled sectoral impacts, as part of a broader disaster-risk approach (Mukwenha et al., 2021).

ECEs are at the sharp end of climate change manifestation and numerous reports and reviews project an intensification of ECEs in the coming years and decades. Globally the threat from ECEs has been receiving special attention from global institutions and programmes. The UN Office for Disaster Risk Reduction, has published Sendai Framework for Disaster Risk Reduction 2015-2030 (UNODIR, 2015) regards climate change as a fundamental source of disaster risk. The IPCC has produced a Special Report entitled Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (Field et al. 2012). Therein is a chapter dedicated to trends in ECEs and their impacts, calling for dedicated attention to these phenomena (Seneviratne , 2012). These reports have been considered at a continental scale (CDKN, 2012) and the South African government has published the National Climate Change Adaptation Strategy (NAS, 2019)  which is, at its heart, concerned about the projection, prediction and mitigation of the impact of ECEs and resulting natural disasters. Furthermore, South Africa is party to a number of programmes and projects (e.g. SASSCAL, WCSSP, iDEWS) which all have climate services components. With a developing emphasis on climate services (sectorally-based) and the conceptualisation of an evidence-based National Climate Services Framework (being implemented by SAWS), the moment is opportune for the establishment of a scientific collaboration among researchers who can give effect to this idea. 

Since the study and application of knowledge regarding the assessment, prediction and projection of ECEs is a multidisciplinary undertaking, requiring the collaboration among statistical analysts, climate modellers, weather forecasters, geographers and sectoral specialists (e.g. crop modellers, infectious disease experts), it is important that a unified platform is established. This will not only bring together disparate efforts focussed on sector-specific or various categories of ECEs, but will provide a common resource (and training) for developing standardized (yet tailored) approaches to their assessment and projection. By incorporating the sectoral research agencies including SAWS, ARC, MRC and the DRMC (and potentially others as the work progresses) the outputs of this work will have a natural home. Importantly the SAWS has an important role to play as the official provider of weather and climate advisories. 

 4.2 Strategic orientation.

This proposal represents the progression of the focus of this ACCESS GCGC programme from basic science to more applied work, implementing a refreshed consortium of researches (with an emphasis on emerging, black and woman researchers) in fulfilment of its mandate form the DSI Outcome 10, to develop: A Functional Climate Change Network. 

W.r.t to section 1 of the call, this proposal manifests outcomes expressed of international (e.g. IPCC and Sendai Framework) and local policy developments, focussing capacity with a trans-disciplinary approach to address environmental issues that “increasingly threaten the very fabric of modern human society”.  W.r.t. section 2, the proposal draws on the notion that “South Africa is also subject to the early impacts of global climate change that appear to be interacting with natural long term climate variability that has been an historical feature impinging upon this region”. W.r.t section 3.2, this project provides for continuity in the ESS efforts (ACCESS) and will, through the case studies, develop targeted observational and modelling capacity. The new consortium forges cooperation and collaboration among a range of individuals and entities from universities, and statutory research and information providing agencies. One of the key goals of the project is to “systematize information w.r.t the evolving national and international risks” (as manifesting in ECEs and their drivers), and “facilitate its access to a wide range of users and decision makers nationally and internationally”.

W.r.t Section 3.3, the proposal addresses drivers of ECEs that emanate from, and impact on, all elements of the earth system, across multi-time scales. The ECEs focus matches precisely with the objective on “the links between climate and earth system processes (trends and cycles and their impacts)” and “extremes and frequency of occurrence”. The proposal will provide “innovative means of using new knowledge for policy, impact, practice and regulation (fostering links to policy and decision-making)”. W.r.t section 3.4, the proposal will develop existing capacity within state agencies (contribute to the development of a capable state), develop new capacity through postgraduate research students, and the leadership of the project (management team) incorporates researchers from designated transformation categories (including 4 HBUs). W.r.t section 3.5, the proposal, focusing on drivers and impacts of ECEs, seeks to “optimize socio-economic benefits through improving scientific understanding of global change”.

The proposal relates specifically to variability at all-time scales (Focus Areas Part 2, section 1), seeks to quantify trends and develop a predictive understanding of socially-relevant impacts of ECEs. Regarding the ESSRP Concept note, this proposal leads directly from the ACyS concept of the ACCESS programme and addresses the concern that, “aspects such as weather systems driving extreme events (fire storms, super droughts, floods) and their repercussions for society and for the ecosystems needs a significant amount of further work”.

This project incorporates the vision for the iDEWS Bureau, and is designed to assist SAWS in updating the operational Fire Index and developing a Multi-Hazard Early Warning System. 

Work-package 1 - Agriculture

WP1 focusses on tools and methods for assessing the ECE likelihoods causing damage or reduced crop production. Drought and flood events have impacts on production and hence forecast approaches, incorporating ECE likelihood, are essential. Building on previous work producing real-time forecast systems for seasonal rainfall and end-of-season crop yield on several farms in summer rainfall regions, the work uses data spanning several decades supplied by the farmers, enabling co-produced sets of forecast products. Moreover, a measure of financial implications according to hindcast probabilities is included.  The work in this WP will expand the number of farms, explore additional statistical models and use and compare results with physical crop models, enabling the linkage to the effects of ECEs through the growing season. An additional component will be to examine the impact of ECEs on the livelihoods of subsistence farmers in the Eastern Cape.

Work-package 2 - Logistics

WP2 is focussed on the reportedly increasing disruptions of port operations that occur due to extreme winds (among other less common causes), typically during summer months and some winter storms. These impact shipping lines, port schedules, stevedores, crane operations (Transnet), freight agencies, shipping agents and customers who require goods to move in and out of the port for manufacturing or retails operations.  The work-package will acquire relevant wind records and data from all the stakeholders in the port and surrounding points for the analysis of the trends in extreme winds. Stakeholder consultation will be required to both understand the problems and needs and to tailor assessments and analysis in order to produce useful information for management and strategic planning interventions.  The economic impact of the disruptions will also be assessed and the methods developed here will be applied to similar assessments in other ports along the coast.

Work package 3 - Health

WP3 focuses on the role of ECEs in contributing to ill-health directly, in the case of heat stress, and the implications for the policy interplay between climate and health. The heat-stress project will involve the calculation of biometeorological indices including the UTCI and PET, and the integration of health data and historical news accounts of heat-stress related mortality and morbidity to assess the climatic thresholds for adverse health outcomes.  The policy project will interrogate existing policy in both the climate and health spheres, and through stakeholder engagement, make recommendations towards developments which would facilitate improved preparedness for health challenges associated with ECEs.

Work package 4 – Land Management

WP4 focuses on Land Management in the context of intensification of wildfires and fire risk in selected areas of South Africa. Fire events are linked to specific meteorological conditions including ECEs such as dry and very hot conditions, as those associated with berg wind conditions over the south coast. Once ignited, strong winds fan runaway fires affecting efforts to contain and extinguish them. The recent Table Mountain fires remind of increasing fire risk and the importance of fire management practices that are informed by science. The more frequent and often underreported fires in dense informal settlements have not received research attention comparable to wildfires on plantations or grasslands.  In addition to a present day fire climatology, this research will analyse case studies of big wildfire events and the occurrence of fires in dense informal settlements. The future of fire risk (danger) will be determined via an ensemble of CMIP6 models under SSP5 scenario whilst socio-economic impacts and costs of fire events are evaluated. Key outputs include improvement of forecasting and management of fire events in South Africa.

Work package 5 - Delivery and dissemination

WP5 focuses on delivery of information generated from this project and from future work on other ECEs and natural disasters. There are several official state agencies that issue a range of information to the public including the DRMC, SAWS and others. This work-package will use the work generated here to evaluate the type of information produced in this project (and related information from elsewhere) and, via consultation, assess the legal and institutional landscape that exists for dissemination of climate service related information. Additionally, a national conference on ECEs and Natural Disasters (with workshops), the WP will produce a report with recommendations on a range of dissemination options (institutional arrangements and processes) and methodologies to ensure that an effective and efficient system is identified for future application.

Key Questions

WPs 1-5: Sectoral case studies – this set of questions will be refined for each case study at the commencement of the project.

Q2.1 What is the narrative of the sectoral ECEs under consideration, what has been published, what systems are already in place for their assessment and prediction and in which way are they deficient?

Q2.2 Is the definition of an ECE useful?  How should it be modified (for real world application)?

Q2.3 Who are the key agencies and stakeholders in this sector w.r.t impact of ECEs?

Q2.4 What are the user-oriented specifications and requirements for early warning of ECEs?

Q2.5 What data exists for assessment of the occurrence and intensity? From which sources?

Q2.6 What are the climate and weather configurations at ranging scales (and their evolution) that are associated with the ECEs?

Q2.7 What data exists for assessing the impact of ECEs in this sector and what are the quantified impacts?

Q2.8 What are the confounding factors to account for in assessment of impact?

Q2.9 What are the trends in the sectoral ECEs and their likely impact?

Q2.10 What are the optimal means or methods of prediction and projection of ECEs at relevant time scales?

Q2.11 What are the predictions and projections of the sectoral ECE?

Q2.12 What systems should be developed for the delivery of ECE information in this sector?