Climate change articles

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    Towards drought impact-based forecasting in a multi-hazard context
    (Elsevier, 2022-01-26) Boult, Victoria L.; Black, Emily; Abdillahi, Halima Saado; Bailey, Meghan; Harris, Clare; Kilavi, Mary; Kniveton, Dominic; MacLeod, David; Mwangi, Emmah; Otieno, George; Rees, Elizabeth; Rowhani, Pedram; Taylor, Olivia; Todd, Martin C.
    The lives and livelihoods of people around the world are increasingly threatened by climate related risks as climate change increases the frequency and severity of high-impact weather. In turn, the risk of multiple hazards occurring simultaneously grows and compound impacts become more likely. The World Meteorological Organization (WMO) proposed the use of multi-hazard impact-based forecasting (IbF) to better anticipate and reduce the impacts of concurrent hazards, but as yet, there are few operational examples in the humanitarian sector. Drought is particularly susceptible to multi-hazard influences. However, challenges encountered in the development of drought IbF systems – including poor understanding of compound impacts and specific hazard-focused mandates – raise important questions for the feasibility of multi-hazard IbF as envisioned by the WMO. With these challenges in mind, we propose an interim approach in which real-time assessment of dynamic vulnerability provides a context for drought-based IbF. The incorporation of dynamic vulnerability indicators account for the local effects of non-drought hazards, whilst the use of a drought-based system facilitates effective intervention. The proposed approach will improve our understanding of compound events, enhance adoption of IbF in the humanitarian sector, and better mitigate the impacts of concurrent hazards.
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    Effect of cadmium uptake and accumulation on growth and antibacterial activity of Merwilla plumbea — An extensively used medicinal plant in South Africa
    (Elsevier, 2009-05-21) Street, R.A.; Kulkarni, M.G.; Stirk, W.A.; Southway, C.; Abdillahi, H.S.; Chinsamy, M.; Staden, J. Van
    In South Africa, heavy metal contamination of agricultural soils is on the increase primarily due to excessive application of fertilizers, sewage disposal and mining activities. The aim of this study was to investigate the effect of cadmium (Cd) on plant growth and biological activity. The medicinal plant Merwilla plumbea [Syn. Merwilla natalensis (Syn. Scilla natalensis)] was selected due to the high demand for its bulbs in the traditional medicine markets. Low levels of Cd (2 mg/L) significantly reduced fresh mass of leaves, bulbs and roots in comparison to the control. Although most of the Cd was stored in the roots, the bulbs, which are used medicinally, accumulated 7.1, 5.9 and 11.6 mg/kg when grown in sand watered weekly with 2, 5 and 10 mg Cd/L respectively. The bulbs of M. plumbea contained 24-fold more Cd than the World Health Organization guideline of 0.3 mg Cd/kg, when irrigated with 2 mg Cd/L. The bulb extracts showed increased antibacterial activity against the Gram-positive bacterium Bacillus subtilis at 2 mg Cd/L. The plants treated with 10 mg Cd/L showed an increased antibacterial activity against B. subtilis, Klebsiella pneumoniae and Staphylococcus aureus in comparison to non-Cd-treated plants (control). However, there was no change in antibacterial activity of the various extracts against the Gram-negative bacterium Escherichia coli. The ability of M. plumbea to accumulate Cd not only raises concern for consumer safety, but also the quality of medicinal plants sold may be in question.
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    Determinants of Household Willingness to Pay for Improved Water Supply: A Case Study of Baringo and Samburu Counties, Kenya
    (Researchgate, 2020-09) Kingori, Sarah; Abdillahi, Halima Saado
    Background: In Sub-Saharan Africa, the supply of affordable, accessible and safe drinking water particularly in rural areas lags behind global progress. Achieving the universal and equitable access objectives warrants an understanding of household behavior in relation to water services. Purpose of the study: The aim of the study was to investigate the factors that influence willingness to pay for improved water service provision in a rural context in Kenya. Methods: A total of 601 households in Baringo and Samburu Counties were randomly selected using probability proportional to size technique. The data was analyzed using descriptive statistics and logit regression. Results: The empirical result shows that demographic characteristics of household, water source, quality and quantity, children responsible for fetching water, water access challenges and frequency of diarrhea are significant variables that explain willingness to pay. Conclusion: The findings conclude with important policy recommendations; (i) demand-driven approaches in the design of water supply projects, (ii) enhanced water quality management, and (iii) awareness creation to achieve social and health benefits which can facilitate long-term access and sustainability.
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    Use of earth observation products to enhance humanitarian disaster response: A Case Study of KRCS Response to West Pokot Mudslides in 2019
    (Researchgate, 2020-12-01) Osunga, Michael; Makena, Betty; Abdillahi, Halima Saado
    Kenya is mostly affected by mudslides and floods during two rainfall seasons, namely March-April-May (MAM) and October-November-December (OND). These landslides, floods and mudslides more often than not lead to loss of human lives, destruction of houses, displacement of people, livestock deaths, loss livelihoods among other impacts. This paper highlights the use of earth observation satellite imageries from the Airbus foundation for-disaster impact assessment during the 2019 OND rainfall season to support effective response. On the 23rd of November 2019 during the OND rainfall season, mudslides and floods occurred in West Pokot resulting in disruption of road accessibility, loss of human lives, loss of livelihoods, houses destruction and displacement of people. Due to continuation of rainfall, roads were cut-off and hence it was difficult to access the area to determine the damage and the number of households affected. Through the partnership with Airbus foundation, International Center for Humanitarian Affairs (ICHA) at Kenya Red Cross Society (KRCS) tasked the Pleiades satellite to acquire imageries of the affected areas five days after the mudslide event. A spot 6 imagery archive captured on the 15th of May 2019 (months before the mudslide event) was downloaded from the Airbus foundation archives. A comparison of these two imageries through change detection was done in order to extract mudslide and flooding hazard extents. A hazard exposure analysis was done in order to determine houses and roads affected by the mudslide and flood hazard. Results from exposure analysis revealed over 145 houses as being destroyed and over 2.1 kilometers of roads being cut-off. Further analysis was done to determine partially and completely destroyed houses. KRCS was able to use this information for post-disaster recovery interventions such as search and rescue as well as shelter initiation of re-construction houses that were completely damaged by floods and mudslides. This study has demonstrated the valuable use of satellite imageries from the Airbus Foundation to KRCS through provision of timely and accurate information on impacts of mudslides and floods in remote and inaccessible areas in a cost-effective manner and further support effective and efficient response and recovery. It is highly recommended for KRCS and other Red Cross and Red Crescent National Societies to use earth observation satellites for post-disaster assessment especially in remote areas that are inaccessible. This by far would improve their humanitarian capacity in conducting post-disaster assessments in a cost-effective and timely manner.
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    FLOOD IMPACT-BASED FORECASTING FOR EARLY WARNING AND EARLY ACTION IN TANA RIVER BASIN, KENYA
    (Researchgate, 2019-09-03) Otieno, O.M.; Abdillahi, H. S.; Wambui, E. M.; Kiprono, K. S.
    Kenya is mostly affected by floods during the March-April-May (MAM) and October November-December (OND) rainfall. This often occurs along river basins such as the Tana river basin, leading to disruption of people’s livelihoods, loss of lives, infrastructure destruction and interruption of economic activities. This study used openly available data on flood exposure, vulnerability, lack of coping capacity, flood impacts and observed satellite rainfall to analyse and predict forecast-based impacts in Tana river. Earth observation satellites including LANDSAT, sentinel 1 and 2 were acquired based on credible flood event dates to validate flood exposure and flood events. The community risk assessment (CRA) approach was used to delineate communities at high risk of floods using combination of data on vulnerability, flood exposure and lack of coping capacity. Using an ordinary least squares (OLS) predictive model, observed satellite rainfall was used as a covariate in order to predict flood impacts on communities with high flood risk scores in Tana river. Weighted scores from the CRA dimensions were summed up with forecasted hazards from the OLS model in order to derive a flood impact-based forecast. The flood impact information is to be used in forecast-based action through early warning, early action protocols thereby reducing impacts of potential floods in communities living in high flood risk areas based on the flood risk map.
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    Mainstreaming forecast based action into national disaster risk management systems: experience from drought risk management in Kenya
    (Taylor & Francis, 2021-11-26) Mwangi, Emma; Taylor, Olivia; Todd, Martin, C.; Visman, Emma; Kniveton, Dom; Kilavi, Mary; Ndegwa, William; Otieno, George; Waruru, Shamton; Mwangi, John; Ambani, Maurine; Abdillahi, Halima; MacLeod, David; Rowhani, Pedram; Graham, Richard; Coleman, Richard
    Drought and food security crises heighten risks to lives and livelihoods in East Africa. In recent years, a shift towards acting in advance of such events has gained momentum, notably among the humanitarian and development community. This shift is premised on tools that link climate forecasts with pre-agreed actions and funding, known as Forecast-based Action (FbA), or anticipatory action more widely. While FbA approaches have been developed by a number of humanitarian agencies, the key to scaling-up is mainstreaming these approaches into national risk management systems. This paper addresses this gap in the context of drought risk management in Kenya. We analyse Kenya’s current drought management system to assess the potential usability of climate forecast information within the existing system, and outline steps towards improved usability of climate information. Further, we note the critical importance of enabling institutions and reliable financing to ensure that information can be consistently used to trigger early action. We discuss the implications of this for scaling-up FbA into national risk management systems.
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    Advancing operational flood forecasting, early warning and risk management with new emerging science: Gaps, opportunities and barriers in Kenya
    (Wiley, 2022-01-27) Kiptum, Augustine; Mwangi, Emma; Otieno, George; Njogu, Andrew; Kilavi, Mary; Mwai, Zacharia; MacLeod, Dave; Neal, Jeff; Hawker, Laurence; O'shea, Tom; Saado, Halima; Visman, Emma; Majani, Bernard; Todd, Martin, C.
    Kenya and the wider East African region suffer from significant flood risk, as illustrated by major losses of lives, livelihoods and assets in the most recent years. This is likely to increase in future as exposure rises and rain- fall intensifies under climate change. Accordingly, flood risk management is a priority action area in Kenya's national climate change adaptation planning. Here, we outline the opportunities and challenges to improve end-to-end flood early warning systems, considering the scientific, technical and institutional/governance dimensions. We demonstrate improvements in rainfall forecasts, river flow, inundation and baseline flood risk information. Notably, East Africa is a ‘sweetspot’ for rainfall predictability at sub- seasonal to seasonal timescales for extending forecast lead times beyond a few days and for ensemble flood forecasting. Further, we demonstrate coupled ensemble flow forecasting, new flood inundation simulation, vulnerability and exposure data to support Impact based Forecasting (IbF). We illustrate these advances in the case of fluvial and urban flooding and reflect on the potential for improved flood preparedness action. However, we note that, unlike for drought, there remains no national flood risk management framework in Kenya and there is need to enhance institutional capacities and arrangements to take full advantage of these scientific advances.