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Start date: 2024Subject: search.filters.subject.SDG-13: Climate action

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    Spatio-temporal trends in daily precipitation extremes over the Enkangala escarpment of South Africa: 1961–2021
    (Springer, 2025-02) Abubakar, Hadisu Bello; Scholes, Mary C.; Engelbrecht, Francois A.
    The Intergovernmental Panel on Climate Change in its Sixth Assessment Report reported that increases in extreme weather events can already be detected in every region in the world. For eastern southern Africa the report provides evidence of an increasing trend in extreme precipitation events, but more research is needed to understand how this change is manifesting over regions as diverse as South Africa’s eastern escarpment and northern Mozambique. This study evaluates the trends in extreme precipitation over the Enkangala Escarpment, part of South Africa’s eastern escarpment, over the period 1961 to 2021. Daily precipitation data covering 22 stations with fewer than 10% missing values over 61 years were obtained from the South African Weather Service. A total of twelve extreme events precipitation indices were computed using the ClimPACT2 package, and a time series trend analysis was performed using the Trend Free Whitening Mann Kendal test and a field significance test. The results indicate significant increasing trends in nine out of the twelve extreme events indices that were investigated. The three indices which have shown significant decreasing trends include Consecutive Wet days (CWD) at (0.03 day/year total annual rainfall (PRCPTOT) (0.61 mm/decade) and the annual count of days when precipitation≥10 mm (R10mm) of 0.32 days/decade. Indices such Rx1 days, Rx3 days and Rx5 days exhibited increasing trends of 0.2 days/decade each. Other indices with an increasing trend are CDD (3.6 day/decade), R20mm (0.2 days/decade) and R30mm (0.2 days/decade). The R95p (11.2 mm/decade) and R99p (6.0 mm/decade) indices, and Simple Daily Intensity Index(0.4 mm/decade) also exhibit positive trends over the study period. Overall the analysis is indicative of a change in the nature of rainfall over the Enkangala escarpment of South Africa, with annual rainfall totals, the number of consecutive wet days and the frequency of events with smaller thresholds such as 10 mm/day decreasing, but with extreme events of larger thresholds occurring more frequently. That is, when it rains, it tends to rain more intensely than in the past. The use of a field significance test was useful to formalise when relatively small but spatially homogeneous trends detected at separate weather stations yield statistical significance. The findings of the paper are relevant to decision and policy in multiple of socio-economic sectors active in South Africa’s eastern escarpment.
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    The synergetic effect of drought and land use changes on Ethiopian Rift Valley Northwestern Escarpment livelihood systems
    (Springer, 2025-02) Gidey, Eskinder; Mhangara, Paidamwoyo; Nasir, Jemal; Zeleke, Tesfaye; Assefa, Engdawork; Kahsay, Shishay; Birhane, Emiru
    Climate change has significantly impacted smallholder farmers in developing countries, where most livelihoods rely on rain-fed agricultural systems. The Northwestern Escarpment of the Ethiopian Rift Valley (NEERV) is among Ethiopia’s most drought-vulnerable areas and is highly affected by land use and land cover change (LULCC). This study aimed to analyze the synergistic impacts of drought and LULCC in the three major livelihood zones (LZs) of NEERV between 1983 and 2019. The study used socioeconomic, climatic, and earth observation datasets. Utilizing a mix of socioeconomic, climatic, and earth observation datasets, this paper investigated the combined effects of these factors on three major livelihood zones: Alagie-Ofla (ALOFLZ), Tsirare catchment (TCLZ), and Raya Valley (RVLZ). The analysis revealed significant rainfall variability, with annual fluctuations between 31 and 50% and seasonal variations ranging from 39 to 99%. This variability has contributed to frequent drought occurrences, with intervals of approximately 2.13 years in ALOFLZ, 2.2 years in TCLZ, and 2.13 years in RVLZ. There has been a notable increase in cultivated and built-up areas across all zones. The study found that drought and LULCC have severely impacted agricultural productivity and local ecosystems, with the most pronounced effects observed in RVLZ, TCLZ, and ALOFLZ. The findings highlight a critical need for integrated approaches to manage and monitor the synergistic impacts of drought and LULCC. The study underscores the importance of enhancing drought and LULCC monitoring systems to improve resilience and adaptability in vulnerable regions. The research contributes to a deeper understanding of how these intertwined factors exacerbate environmental and socioeconomic challenges, offering valuable insights into policy and management strategies for mitigating their effects. Recommendations include enhancing the current drought and LULCC monitoring systems to improve predictions and mitigation efforts, thus bolstering resilience and adaptability among affected communities.
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    The Care-Climate Nexus - A Conceptual Framework
    (2025-01) Phalatse, Sonia; Taylor, Julia; Valodia, Imraan
    As is widely acknowledged and evidenced, climate change threatens food security and sovereignty; water availability, accessibility and quality; health and livelihoods. Where women bear the primary responsibility of unpaid care work such as food provision, water collection, and care for the young, sick and elderly, climate change disproportionately disadvantages them. This applies to the work of care and, more broadly, to social reproduction. Climate change thus contributes to an ongoing crisis of care, exacerbating the injustices associated with women carrying a disproportionate share of unpaid care. As such, fostering a value for care could be a means through which social and environmental inequalities are equally addressed in an ecological transition. This paper expands on the conceptual linkages of a care-climate nexus, with the aim of supporting climate policy.
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    Key barriers to green building implementation in South Africa
    (University of the Witwatersrand, Johannesburg, 2024-07) Mompati, Lerato; Mandlate, Mike; Kabini, Karabo; Nomvalo, Usiphe; Laryea, Samuel; Li, Baizhan; Essah, Emmanuel Adu; Mensah, Sarfo; Liu, Hong; Yao, Runming
    Due to climate change, South Africa is faced with economic and health challenges. Adopting green building technologies reduces the amount of energy usage, however the implementation of green building in South Africa has been slow. This research aimed to identify the barriers on the implementation of green building and the methods that can be adopted to enhance the growth of green building in South Africa. A qualitative research method was be adopted. The open-ended interviews were conducted with built environment professionals. The main barriers of green building implementation are: initial high cost, lack of awareness, lack of incentives, and resistance to change. Recommendations to enhance the growth of green building practices in South Africa include: updating building codes, expanding training programs, fostering collaboration between the public and private sectors, offering financial incentives, promoting the re-purposing of existing structures, and using performance-based contracts. The paper has highlighted the key barriers of green building implementation in South Africa and developed a database of the relevant studies which can further guide future researchers, stakeholders and policymakers in this area.
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    Impacts of heat exposure in utero on longterm health and social outcomes: a systematic review
    (BioMed Central (BMC), 2024) Norris, Shane; Brink, Nicholas; Lakhoo, Darshnika P.; Solarin, Ijeoma; Maimela, Gloria; von Dadelszen, Peter; Chersich, Matthew F.
    Background: Climate change, particularly global warming, is amongst the greatest threats to human health. While short-term effects of heat exposure in pregnancy, such as preterm birth, are well documented, long-term effects have received less attention. This review aims to systematically assess evidence on the long-term impacts on the foetus of heat exposure in utero. Methods: A search was conducted in August 2019 and updated in April 2023 in MEDLINE(PubMed). We included studies on the relationship of environmental heat exposure during pregnancy and any long-term outcomes. Risk of bias was assessed using tools developed by the Joanna-Briggs Institute, and the evidence was appraised using the GRADE approach. Synthesis without Meta-Analysis (SWiM) guidelines were used. Results: Eighteen thousand six hundred twenty one records were screened, with 29 studies included across six outcome groups. Studies were mostly conducted in high-income countries (n=16/25), in cooler climates. All studies were observational, with 17 cohort, 5 case-control and 8 cross-sectional studies. The timeline of the data is from 1913 to 2019, and individuals ranged in age from neonates to adults, and the elderly. Increasing heat exposure during pregnancy was associated with decreased earnings and lower educational attainment (n=4/6), as well as worsened cardiovascular (n=3/6), respiratory (n=3/3), psychiatric (n=7/12) and anthropometric (n=2/2) outcomes, possibly culminating in increased overall mortality (n=2/3). The effect on female infants was greater than on males in 8 of 9 studies differentiating by sex. The quality of evidence was low in respiratory and longevity outcome groups to very low in all others. Conclusions Increasing heat exposure was associated with a multitude of detrimental outcomes across diverse body systems. The biological pathways involved are yet to be elucidated, but could include epigenetic and developmental perturbations, through interactions with the placenta and inflammation. This highlights the need for further research into the long-term effects of heat exposure, biological pathways, and possible adaptation strategies in studies, particularly in neglected regions. Heat exposure in-utero has the potential to compound existing health and social inequalities. Poor study design of the included studies constrains the conclusions of this review, with heterogenous exposure measures and outcomes rendering comparisons across contexts/studies difficult.