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Wetlands provide numerous ecosystem services essential for biodiversity conservation, climate change mitigation, and human well-being. Nevertheless, there are still no complete and uniform wetland maps providing information on the location, distribution, size, and changing status of wetlands in Africa. In this study, we used 130,000 Landsat satellite images and 270,000 sampling points evenly distributed across Africa to classify wetlands with a random forest classifier based on the Google Earth Engine (GEE) cloud platform. This resulted in the first systematic and comprehensive map of existing wetlands in Africa that quantified the area and distribution of these wetlands at a spatial resolution of 30 m, with an overall wetland producer accuracy of 90.22 % and user accuracy of 95.74 %. To address the seasonal variation in African wetlands, we used a dynamic threshold segmentation method based on the Otsu method, which can extract the extent of wetlands under different periods more accurately based on Landsat time series and African phenology data. Our results show that the total African existing wetlands extent from 2019 to 2021 (here in 2020), was approximately 1,341,500 km2, excluding shallow marine waters, comprises 3.98 % of Africa's total land area. Of these wetlands, inland wetlands account for 81 %, and coastal wetlands account for 19 %. The wetlands in Africa were symmetrically distributed around the equator and decreased with increasing latitude, accounting for 97 % of the total wetland area being within the 20°N and 20°S latitudes. African marshes were highly dynamic, expanding by 92.22 % from the dry to wet season. Our study demonstrates the substantial potential of large data samples, multiple wetland classification features (spectral-temporal, topographic, and hydrological features), and random forest classification in GEE for large-scale wetland mapping. The resulting wetland maps provide new baseline data for large-scale monitoring of seasonal dynamics and long-term trends in African wetlands. [ABSTRACT FROM AUTHOR]

Efforts to avoid the acceleration of global warming have tended to focus on countries with high CO 2 emissions levels and large populations, with a high level of economic development or industrialization. African countries, which often do not conform to such criteria, are more vulnerable to climate change due to their dependence on climate-sensitive industries and their limited infrastructure and technological capacity to cope with its impacts. The long-term economic growth rates projected for Africa's rapid development period will, further, make Africa a potential emission hotspot in the near future. Here, for the first time, we built an energy-related emissions inventory for 19 African countries for 2010–2019, which addresses emissions from 47 economic sectors and 5 energy types, making it the most comprehensive of its kind. The degree of decoupling of economy and emissions, and drivers of CO 2 emission changes are also examined. Most African countries experienced rapid growth in CO 2 emissions, with an average annual growth rate of 5.5% for fossil fuel-related CO 2 emissions and 6.0% for unsustainable biomass-related CO 2 emissions. Only two countries, South Africa and Tanzania, have achieved a strong decoupling of economic growth from CO 2 emissions. Economic and population are the most important drivers of emissions, while energy intensity has been identified as a key factor in mitigating CO 2 emissions, especially for those countries that have reached strong or weak decoupling. The findings from this study provide essential insights that could guide the development of low-carbon policies and strategies in Africa. • We provide energy-related emission inventories for 19 African countries from 2010 to 2019. • African countries experienced rapid growth in CO2 emissions. • Two countries achieved strong decoupling of GDP from CO2 emissions. • Economic and population growth are the most important drivers of emissions. [ABSTRACT FROM AUTHOR]

Local governments are expected now more than ever to lead climate action planning as climate change intensifies and urbanization increases rapidly. However, studies indicate limitations in the comprehensiveness and level of integration of adaptation and mitigation in existing climate action plans. To develop suitable climate action plans that are comprehensive and consistent with globally accepted standards and benchmarks, this study proposed an Urban Climate Action Planning framework and pilot-tested it with 257 urban climate action plans. Overall, 43 criteria are included in the framework across three stages of climate planning. The pilot test revealed that more than half of the sampled plans have a medium level of suitability, with 39% having a weak level of suitability. About 51% of plans from Europe have a weak level of suitability. Surprisingly, none of the plans sampled from Africa and Latin America achieved a weak level of suitability despite lacking a significant share of global climate research and development funding. A Kruskal-Wallis test shows a statistically significant association between stages of climate planning and (a) city types (p-value of 0.004326) and (b) year of adoption or publication of climate plans and suitability scores (p-value of 0.0001027). Urban climate action plans adopted or published more recently (2018–2022) are likely more suitable than those adopted or published earlier. The sampled urban climate action plans from the Global South had higher average suitability scores than those from the Global North. The study presents key findings and considerations for urban climate action planning and future research. [Display omitted] • A framework for assessing the suitability of Climate Action Plans (CAPs) is proposed. • The framework is used to pilot-test the suitability of 257 urban CAPs. • Suitability analysis is done across city types, regions, and the global divide. • Most sampled plans achieved a medium level of suitability. • The CAPs lack criteria related to implementation and monitoring. [ABSTRACT FROM AUTHOR]

The ongoing global warming is projected to persist throughout the entire century if effective mitigation measures are not put in place. The warming is associated with occurrence of extreme climate events that are prone over Africa. This study uses model data from 24 CMIP6 modeling centers to investigate future changes in extreme climate events over Africa under 1.5 °C, 2.0 °C and 3.0 °C global warming levels (GWLs). The amplified impact in extreme climate events by additional is computed relative to GWL1.5 °C. The models generally simulate observed climate extremes well, with the ensemble mean minimizing data uncertainties. The entire continent is projected to get warmer with the Sahara, Kalahari and parts of the Mediterranean depicting relatively higher temperatures. Both Rx1day and Rx5day are projected to increase over the continent except for the northern and southern regions of the continent. Rx5day is projected to increase by 4–10% for GWL1.5 and GWL3.0 °C. In comparison, an additional 0.5 °C warming between GWL2.0 °C and GWL1.5 °C will lead to an increase of about 43% impact for the climate extremes. An additional GWL1.5 °C (GWL3.0 °C) could result in about 68% increment in climate extremes. The amplified impact of global warming will result in devastating socioeconomic impacts over Africa. This stresses the need of formulating and implementing more ambitious climate change mitigation measures in effort to limit global warming to 1.5 °C. • Future changes in extreme climate are projected over Sahara, Kalahari and parts of the Mediterranean region. • Higher increase in Rx5day compared to Rx1day is projected for GWL1.5 – GWL3.0 °C. • Additional 0.5 °C (GWL1.5 °C) warming will lead to an increase of about 43% (68%) impact for the climate extremes. [ABSTRACT FROM AUTHOR]

• Amplification effects of higher air temperature on the range of changes in flood frequency and magnitude are projected. • Southeast Eurasia, Africa, and South America are hotspots with higher flood defense pressures. • Most watersheds worldwide would face increasing pressures from current flood defense standards in warming climates. Floods usually threaten human lives and cause serious economic losses, which can be more severe with global warming. Therefore, it is a salient challenge to find out how global flood characteristic changes and whether current flood protection standards will face more pressures. This study aims to characterize changes in global floods and explicit flood defense pressures in warming climates of 1.5–3.0 °C above pre-industrial levels by running four well-calibrated lumped hydrological models using bias-corrected Global Climate Model (GCM) simulations for 9045 watersheds worldwide. The results show that global warming from 1.5 to 3.0 °C has increasingly dominated all continents, with amplification effects on changes of flood frequency and magnitude. Southeast Eurasia, Africa, and South America are hotspots of changes for significant proportions of watersheds with larger flood patterns and greater changing extents than others. For example, for the 3.0 °C warming period under the combination of shared socioeconomic pathway 2 and representative concentration pathway 4.5 (SSP245) scenario, the regionally averaged 50-year flood magnitude will increase by 25.6 %, 30.6 %, and 16.4 % for these regions, respectively. The increases in occurrence and magnitude indicate that current flood protection standards will face increasing pressures in future warming climates. The design-level flood frequency is projected to increase for about 47 %, 55 %, 70 %, and 74 % of watersheds in 1.5, 2.0, 2.5, and 3.0 °C warming periods under the SSP245 scenario. However, large uncertainty are observed for the change of flood characteristics dominated by GCMs and their interactions with SSP scenarios and hydrological models. This study implies that the current flood defense standards should be enhanced and climate adaptation and mitigation strategies should be proposed to cope the change of future flood. Floods usually threaten human lives and cause serious economic losses, which can be more severe in the context of global warming. It is a salient challenge to find out how global flood risk changes and whether current flood protection standards will face more pressures. This study aims to characterize changes in global floods and explicit flood defense pressures in warming climates of 1.5, 2.0, 2.5, and 3.0 °C above pre-industrial levels. Here we show that amplification effects of higher air temperature on the range of changes in flood frequency and magnitude are projected. Southeast Eurasia, Africa, and South America are hotspots of changes for significant proportions of watersheds with larger flood patterns and greater changing extents than others. Most watersheds worldwide is likely to face increasing flood defense pressures in warming climates. Our findings could improve the understanding of future flood conditions under the warming climates and provide information to mitigation and adaptation policymaking. [ABSTRACT FROM AUTHOR]

Despite renewed efforts to combat climate change, it remains uncertain how economies will achieve emission reduction by 2050. Among different decarbonisation strategies, knowledge about the potential role and contributions of social movements to curbing carbon emissions has been limited. This study aims to shed light on the diverse contributions of social movements to staying within the global carbon budget, as well as on the specific outcomes and strategies employed in protests against hydrocarbon activities. For this purpose, we conduct a systematic literature review of 57 empirical cases of social movements contesting fossil fuel projects in 29 countries. Based on an exploratory approach, we identify a series of different movement strategies and a range of qualitative contributions that support staying within the carbon budget. These include raising awareness of risks and strategies, enhancing corporate responsibility, being informed about policy changes, laws and regulations, fostering just energy transitions, energy democracy, divestment, alternative market solutions, and forcing the postponement or cancellation of targeted hydrocarbon activities. While the institutional means are widely used and seem to support policy change and regulation, these strategies are not used to deliver awareness or postponement outcomes. Similarly, while movements tend to rely on civil disobedience to stop hydrocarbon projects in the short term, they rely on multiple strategies to cancel them in the longer term. Our study also indicates significant knowledge gaps in the literature, particularly, cases in Africa and Central Asia, women's participation in these movements, in addition to more quantitative assessments of the actual emissions reduced by social movements. [ABSTRACT FROM AUTHOR]

Formally adopting climate change mitigation policies does not necessarily translate to tangible change on the ground. Here, we analyse 31 semi-structured interviews with climate policy government officials and consultants from 11 low-income and lower-middle income countries (LMICs) as well as the respective climate policy context, and find high average degrees of perceived discrepancies between formally adopted climate change mitigation policies and their actual implementation. Our results suggest that for our LMIC sample, both the global political process to limit climate change and domestic environmental threats have been key to drive the formal adoption of climate change mitigation policies, but have had limited effect on implementation. By contrast, momentum for implementation of climate change mitigation initiatives and projects on the ground emerges where climate policies are firmly embedded within economic and social development policies, the economy and society are comparably well-positioned to embrace the associated change, and where they have been governed by cross-ministerial institutions capable of implementing wider climate-compatible development pathways. Thus, to help translate climate policy into action, national LMIC governments and the international community need to find context-specific ways to successfully integrate climate with economic and social development policies, identify and build on feasible opportunities and competitive advantages through which the local economy can benefit from green growth, build adequate social capital, and actively create institutional spaces and processes for well-equipped and meaningful cross-ministerial co-benefit governance. The importance of unlocking co-benefits for implementing climate policies underlines both the urgency with which the international community needs to increase finance for LMICs for climate change mitigation, as well as the associated development opportunities. [ABSTRACT FROM AUTHOR]

Crassulacean Acid Metabolism (CAM) plants have the potential to provide future-proof biomass growth under increasingly stressed climatic conditions. Using active cultivation and anaerobic digestion, CAM plants can be grown and fermented to produce biogas or hydrolysed to extract valuable volatile fatty acids (VFAs) which can be applied to a range of uses: energy provision, protein and bioplastic production, carbon sequestration. However, an understanding of the spatial potential for CAM plants to be actively grown and harvested for bio-economic uses across Africa is unknown. A combined conservative assessment which incorporates three key dimensions is lacking from the literature: i) where can CAM plants physiologically grow? ii) where can CAM plants be cultivated without competing with existing land use? and iii) where lies the greatest energy demand? Answering these three questions and mapping the spatial variability between these aspects is essential to the future bioplastics/protein sector and opportunity to capitalise on generating sustainable energy which can connect off-grid rural and peri-urban communities whilst also achieving climate change mitigation targets. Using Opuntia ficus-indica as an example, this study compares two measures of land suitability estimation based on ecophysiological requirements and social, environmental and land-use masks. Focusing on abandoned land, conservative baseline estimates suggest that c.28–55 million hectares of land may be suitable for active CAM cultivation, with the potential to repurpose degraded lands and provide alternative bio-economic livelihoods to communities across semi-arid regions of Africa. [ABSTRACT FROM AUTHOR]