Editor’s Choice Articles

The City of Palma de Mallorca has been historically affected by flood events, with the latest flood of great magnitude occurring in 1962. After decades without large flooding events, since the start of the 21st century, 28 floods have been identified within the city boundaries. As change in the spatial location of these events has been observed, a research to identify where the floods are located nowadays and which causes can be related to such distribution has been undertaken. Six types of floods were identified and the events classified accordingly, with the deficient planned infrastructures, flat urban areas without defined drainage and coastal sectors the three most common types. The results highlight the importance of the urban sprawl and malpractices related to flood risk areas, thus increasing the occurrence of floods of less spatial impact but with greater disturbance on the daily activity of the city inhabitants. Nevertheless, some uncertainties are identified in this research, demonstrating the need of further investigations. Full article

According to the United Nations (2020), since the 1980s, the global overall rate of water use has grown by 1% per year, and it is projected that, by 2050, humanity’s water footprint could exceed 30% of current levels. This situation is in stark contrast to the path toward the Sustainable Development Goals, especially Goal 6, “clean water and sanitation”, which also influences Goal 14, “life below water”, and Goal 15, “life on land”. This is because the availability of water directly affects the food security and production capacity of each Country, and therefore its management is a crucial issue worthy of particular attention. Problems related to water security are particularly evident in the Mediterranean area, which is already facing high environmental challenges. It is an area severely affected by global warming; thus, it is one of the most vulnerable environments to climate change globally. It follows that the improper management of water resources could further worsen an already alarming situation. This research aims to study the main water-related challenges that Mediterranean Countries face, highlighting the significant problems that weaken each Country. In this regard, the indicators relating to Goal 6 were considered, to define each Country’s current state. However, for a correct understanding, the main problems these Countries face were researched through a critical review of the literature (Scopus, Google Scholar, Web of Science). In this way, we were able to underline the effects of human activities on the hydrosphere and the repercussions on various ecosystems, following the drivers-pressures-state-impact-response causal framework. The results suggest that there is still a long way for Mediterranean Countries to progress toward Agenda 2030, as they face problems related to chemical (nitrate, microplastics, heavy metals, pesticides, etc.) and biological (E. coli and other microorganisms) pollution, as well as saline aquifers, absent or obsolete infrastructures, and transboundary basins. Hence, this study aims to provide valuable tools for a better evaluation of water management in Mediterranean Countries. Full article

Due to their authentic urban and architectural character, the Medinas of Tunis and Marrakesh became listed among the United Nations educational, scientific, and cultural organization (UNESCO) heritage sites in 1979 and 1985, respectively. Nowadays, the urbanization of the surrounding green areas and the climate change impacts on cities are degrading the Medinas’ livability and their characteristic heritage. On the other hand, scientific knowledge and data about the green system in the dense urban cores of Medinas in the Maghreb region is still not a widely apprehended theme in the scientific domain. This research objective is to initiate nature-based and sustainable solutions in these cities by demonstrating the application of the urban green infrastructure (UGI) approach. As a research methodology, an analysis of the historical green system development in the Medinas is given to highlight their tangible and intangible values. The analysis goes over three periods: first, the medieval Islamic era, then the modern period during the French colony, and the contemporary city as a unique urban landscape. Finally, the study proposes a design guideline to prove the applicability of the UGI in the given historical morphologies by implementing the retained historical values of the historic green heritage in Medinas and the aspects of the site. Full article

Bats populations and their habitats are currently threatened globally, but particular declines have been seen across Europe. The contingent valuation method is commonly used to assign an economic value to species conservation through a willingness to pay (WTP) surveys. We carried out face-to-face interviews of a representative to the Greek population sample (n = 1131) and used a multiple-bounded discrete choice approach to estimate WTP for bat conservation. More than half of the Greek population was supportive of bat conservation (54.6%). Mean WTP was estimated at €21.71, and the total amount that could be collected was €105.6 million, after considering the number of taxpayers and the proportion of supportive people. There was an interplay between emotions, with likeability being the most important positive predictor of support, and fear the most important negative predictor of WTP for bat conservation. Among sociodemographics, older participants, with higher education, farmers, and pet owners showed the highest support, while those with higher education, farmers, and consumptive recreationists offered the highest bid for bat conservation. Participants drew information about bats mostly from informal sources, such as friends, movies, novels, and comics. Our study allowed for the estimation of public support and necessary funds for bat conservation, which are valuable for successful conservation management. Findings will also be critical for the design and implementation of effective education and outreach programs, aimed at increasing knowledge about bats and ultimately support for bat conservation actions. Full article

Bushfires are an integral part of the forest regeneration cycle in Australia. However, from the perspective of a natural disaster, the impact of bushfires on human settlements and the environment is massive. In Australia, bushfires are the most disastrous natural hazards. According to the records of the Parliament of Australia, the recent catastrophic bushfires in NSW and Victoria burnt out over 10 million hectares of land, a figure more significant than any previous bushfire damage on record. After the deadly 2009 Black Saturday bushfires, which killed 173 people in Victoria, public attention to bushfires reached a new peak. Due to the disastrous consequences of bushfires, scientists have explored various methods to mitigate or even avoid bushfire damage, including the use of bushfire alerts. The present study adds satellite imagery and GIS-based semi-real-time bushfire contents to various bushfire warnings issued by government authorities. The new product will disseminate graphical bushfire contents to rural Australians through social media, using Google Maps. This low-cost Media GIS content can be delivered through highly popular smartphone networks in Australia through social media (Facebook and Twitter). We expect its success to encourage people to participate in disaster mitigation efforts as contributors in a participatory GIS network. This paper presents a case study to demonstrate the production process and the quality of media GIS content and further discusses the potential of using social media through the mobile network of Australia while paying attention to mobile blackspots. Media GIS content has the potential to link with the public information systems of local fire management services, disseminate contents through a mobile app, and develop into a fully automated media GIS content system to expand the service beyond bushfires. Full article

The Sustainable Development Goals (SDGs) and their indicators provide opportunities to best combine the available knowledge and data to monitor and estimate different metrics and track their progress. The overall picture can be complex as some indicators are often interconnected (e.g., rural and/or urban development with a water body’s status). Two factors can play a crucial role in achieving the SDGs: the use of new technologies for database building and multidisciplinary studies and understanding. This study aims to explore these factors, highlight their importance and provide an example as guidance of their proper and combinative use. Ireland is used as an example of a data-scarce case with poor–slow progress, especially on the environmental SDGs. Two “non-reported” SDG indicators (lack of data) are selected and estimated in this work using freely available data (remote sensing, satellite imagery) and geospatial software for the first time in the country. The results show improvements in rural and urban development; however, this is accompanied by negative environmental consequences. A more holistic approach is needed and a broader conceptual model is presented to avoid any misleading interpretations of the study of SDGs. The transition to the modern technological and multidisciplinary evolution requires respective knowledge and understanding, strongly based on complex systems analysis. Full article

Air pollution continues to be of concern for Bulgarian cities, mainly due to particulate matter of aerodynamic diameter smaller than 10 μm (PM₁₀). There is public and expert interest in the improvement of two operational air quality modeling systems: the Bulgarian Chemical Weather Forecast System (BgCWFS) and the Local Air Quality Management System (LAQMS) for the city of Plovdiv. The aim of the study is to investigate the effects of satellite data assimilation in BgCWFS on surface concentrations over Bulgaria (resolution 9 km), to downscale BgCWFS output to LAQMS (resolution 250 m), and to examine effects on PM₁₀ in Plovdiv. Data from the Global Ozone Monitoring Experiment-2 (GOME-2) (MetOP satellites) for aerosols, nitrogen dioxide (NO₂), and sulfur dioxide (SO₂) were assimilated in BgCWFS using objective analysis. Simulation experiments with and without satellite data were conducted for a summer and a winter month. The comparison to surface observations in the country showed improvement of results when using satellite data, especially in the summer due to mineral dust events captured by satellites. The decrease in the normalized mean bias (NMB) over the two months was 43% (PM₁₀) and 73% (SO₂). The LAQMS estimated background contributions to PM₁₀ in the city as 32%. The absolute NMB by LAQMS decreased by 38%. Full article

Mountainous regions present numerous obstacles to agriculture. These include the terrain, which is associated with surface erosion, as well as surface runoff, which washes away plant nutrients and weak soil. Spatial analysis is currently used in the study of various stochastic variables, especially those of high priority for soil water properties. Small watershed and basin-scale models were used to simulate the quantity of surface run-off, groundwater and predict the environmental impact of land use and land management practices. A new generation of the distributed hydrological models has greatly broadened simulation fields to soil and water diversified situations. The study also measured declines in slope and grain size distribution, factors impacting surface erosion and surface runoff. Multivariate statistics (canonical analysis) showed that soil moisture was most correlated both with agricultural land and forests, which is why it was used to create the model of spatial distribution. The model showed that salinity has the smallest forecast error in modeling, and thus best corresponds with the soil moisture. It is important to make a correct diagnosis of soil properties, and the degree of degradation. The assessment of the physiographic parameters of a basin will contribute to the development of proper usage and determine the quality of the water in the soil, which will be essential for forest resources and agricultural land in mountain areas exposed to surface erosion. Full article

Natural resources are gradually coming under continuous and increasing pressure due to anthropogenic interventions and climate variabilities. The result of these pressures is reflected in the sustainability of natural resources. Significant scientific efforts during the recent years focus on mitigating the effects of these pressures and on increasing the sustainability of natural resources. Hence, there is a need to develop specific indices and indicators that will reveal the areas having the highest risks. The Water and Land Resources Degradation Index (WLDI) was developed for this purpose. WLDI consists of eleven indicators and its outcome results from the spatiotemporal performance of these indicators. The WLDI is based on the Standardized Drought Vulnerability Index (SDVI) and the Environmentally Sensitive Areas Index (ESAI). The WLDI is applied for the period from October 1983 to September 1996, considering Greece as a study area. The results of the application of this index reveal the areas with the highest risks, especially in the agricultural sector, with less than the needed water quantities due to extensive periods of droughts. This index could be used by scientists, but also by policy makers, to better and more sustainably manage environmental pressures. Full article

This study aimed to reconstruct the sedimentation rates over time and identify the changing sources of sediment in a major hydropower reservoir in Tanzania, the Nyumba ya Mungu (NYM). Fallout ²¹⁰Pb measurements were used to estimate age of sediment deposits and broad changes in sedimentation rates were reconstructed. Sedimentation peaks were cross referenced to geochemical profiles of allogenic and autogenic elemental constituents of the sediment column to confirm a causal link. Finally, geochemical fingerprinting of the sediment cores and potential sources were compared using a Bayesian mixing model (MixSIAR) to attribute the dominant riverine and land use sources to the reservoir together with changes through recent decades. Reservoir sedimentation generally increased from 0.1 g cm⁻² yr⁻¹ in the lower sediment column to 1.7 g cm⁻² yr⁻¹ in the most recent deposits. These results correlated to changes in allogenic and autogenic tracers. The model output pointed to one of two major tributaries, the Kikuletwa River with 60.3%, as the dominant source of sediment to the entire reservoir, while the other tributary, Ruvu River, contributed approximately 39.7%. However, downcore unmixing results indicated that the latest increases in sedimentation seem to be mainly driven by an increased contribution from the Ruvu River. Cultivated land (CU) was shown to be the main land use source of riverine sediment, accounting for 38.4% and 44.6% in Kikuletwa and Ruvu rivers respectively. This study explicitly demonstrated that the integration of sediment tracing and dating tools can be used for quantifying the dominant source of sediment infilling in East African hydropower reservoirs. The results underscore the necessity for catchment-wide management plans that target the reduction of both hillslope erosion reduction and the sediment connectivity from hillslope source areas to rivers and reservoirs, which will help to maintain and enhance food, water and energy security in Eastern Africa. Full article

The present study investigated the effect of biomass burning on the water cycle using a case study of the Chari–Logone Catchment of the Lake Chad Basin (LCB). The Chari–Logone catchment was selected because it supplies over 90% of the water input to the lake, which is the largest basin in central Africa. Two water balance simulations, one considering burning and one without, were compared from the years 2003 to 2011. For a more comprehensive assessment of the effects of burning, albedo change, which has been shown to have a significant impact on a number of environmental factors, was used as a model input for calculating potential evapotranspiration (ET). Analysis of the burning scenario showed that burning grassland, which comprises almost 75% of the total Chari–Logone land cover, causes increased ET and runoff during the dry season (November–March). Recent studies have demonstrated that there is an increasing trend in the LCB of converting shrubland, grassland, and wetlands to cropland. This change from grassland to cropland has the potential to decrease the amount of water available to water bodies during the winter. All vegetative classes in a burning scenario showed a decrease in ET during the wet season. Although a decrease in annual precipitation in global circulation processes such as the El Niño Southern Oscillation would cause droughts and induce wildfires in the Sahel, the present study shows that a decrease in ET by the human-induced burning would cause a severe decrease in precipitation as well. Full article

World Heritage is the pinnacle of the recognition of the natural, aesthetic, and cultural value of a place on the planet. Since its inception in 1972, over 1100 sites have received World Heritage status. Many of these places are being challenged by the effects of climate change. Urgent action is needed to build the resilience and adaptive capacity of World Heritage sites in the face of climate change threats to come. The Wet Tropics of Queensland World Heritage Area (WTWHA) is one of the most effectively regulated and managed protected Areas in the world. This includes the scientific evidence upon which that regulation and management is based. However, there is growing evidence that climate change impacts are a clear and present threat to the Outstanding Universal Value (OUV) upon which the listing is based. This challenges the very concept of OUV and points to the business-as-usual regulation and management not being sufficient to deal with the threat. It also calls for quantum changes in the approaches to protecting natural and cultural heritage and the OUV in World Heritage Areas. This WTWHA case study gives insights into the journey travelled and the pathways that need to be laid out to protect our most cherished internationally recognised natural and cultural landscapes. We demonstrate the importance of evidence in support of advocacy and management action to address the clear impacts of climate change on species, ecosystems, people, and societies living in the WTWHA. The strategic and climate adaptation plans provide the framework upon which these actions take place. Community engagement in the delivery of mitigation, adaptation, and resilience policy is key to the long-term future of the WTWHA. Full article

Machine learning (ML), as an artificial intelligence tool, has acquired significant progress in data-driven research in Earth sciences. Land Surface Models (LSMs) are important components of the climate models, which help to capture the water, energy, and momentum exchange between the land surface and the atmosphere, providing lower boundary conditions to the atmospheric models. The objectives of this review paper are to highlight the areas of improvement in land modeling using ML and discuss the crucial ML techniques in detail. Literature searches were conducted using the relevant key words to obtain an extensive list of articles. The bibliographic lists of these articles were also considered. To date, ML-based techniques have been able to upgrade the performance of LSMs and reduce uncertainties by improving evapotranspiration and heat fluxes estimation, parameter optimization, better crop yield prediction, and model benchmarking. Widely used ML techniques used for these purposes include Artificial Neural Networks and Random Forests. We conclude that further improvements in land modeling are possible in terms of high-resolution data preparation, parameter calibration, uncertainty reduction, efficient model performance, and data assimilation using ML. In addition to the traditional techniques, convolutional neural networks, long short-term memory, and other deep learning methods can be implemented. Full article

Streamflow and sediment flux variations in a mountain river basin directly affect the downstream biodiversity and ecological processes. Precipitation is expected to be one of the main drivers of these variations in the Himalayas. However, such relations have not been explored for the mountain river basin, Nepal. This paper explores the variation in streamflow and sediment flux from 2006 to 2019 in central Nepal’s Kali Gandaki River basin and correlates them to precipitation indices computed from 77 stations across the basin. Nine precipitation indices and four other ratio-based indices are used for comparison. Percentage contributions of maximum 1-day, consecutive 3-day, 5-day and 7-day precipitation to the annual precipitation provide information on the severity of precipitation extremeness. We found that maximum suspended sediment concentration had a significant positive correlation with the maximum consecutive 3-day precipitation. In contrast, average suspended sediment concentration had significant positive correlations with all ratio-based precipitation indices. The existing sediment erosion trend, driven by the amount, intensity, and frequency of extreme precipitation, demands urgency in sediment source management on the Nepal Himalaya’s mountain slopes. The increment in extreme sediment transports partially resulted from anthropogenic interventions, especially landslides triggered by poorly-constructed roads, and the changing nature of extreme precipitation driven by climate variability. Full article

The transportation sector of Senegal is dominated by the road subsector, which relies on fossil fuels: gasoline and diesel. Their combustion generates substances such as carbon dioxide, methane, nitrous oxide, and many others responsible for climate change, which has negative impacts on the environment, human health, and activities. This study is based on data collected from Senegal’s official reports on transport and energy, and Intergovernmental Panel on Climate Change (IPCC) greenhouse gases’ analysis methods. In the period 2000–2013, growing emissions were experienced, reaching up to 2.38 × 10⁶ tCO₂-eq in 2013. The aging vehicle fleet (~20 years old on average), made up of light-duty vehicles (around 85%), a fast-growing number of imported cars, and the predominance of diesel engines (around 59%) are the aggravating factors. Beyond climate change, other gaseous substances resulting from the combustion of fuels such as carbon monoxide (CO), sulfur oxide (SO₂), and particle matters (PMs) contribute to the deterioration of the outdoor air quality. Therefore, it is becoming urgent to monitor the evolution of these emissions and take appropriate measures to reduce their concentrations in the atmosphere. The Government of Senegal has taken a step forward through the modernization of transport infrastructure, and the creation of a center dedicated to the monitoring of outdoor air quality (Centre de Gestion de la Qualité de l’Air—CGQA) and a center in charge of the technical control of vehicles (Centre de Contrôle Technique des Véhicules Automobiles—CCTVA) in Dakar, but much remains to be done. Full article

(1) Background: Human activity is warming the planet and destabilizing the climate through greenhouse gas emissions, which underscores the need for climate communication to overcome barriers to action. (2) Methods: We launched a five-month campaign that included questionnaires (n = 500) and one-on-one interviews (n = 24) to assess climate change sentiment, engagement, adaptation, as well as understand who climate outreach reaches and the observations and concerns such groups report across the U.S. so as to better understand the local context of climate change and enable more effective climate communication and outreach in the future. (3) Results: Results showed outreach efforts to mostly reach college educated Caucasians who identified as Democrats. “Future generations” was the most frequently ranked climate concern, with the economy, property value, and national security ranked last. Communities frequently observed hotter temperatures, increased flooding, and species impacts. Among “climate-concerned” individuals, the majority reported never contacting a local politician about climate change. College students least frequently reported climate change as a top priority and reported a low frequency of civic engagement on the issue. In-person interviews highlighted climate impacts disproportionately affecting low-income communities and communities of color, such as heat-related mortality and gentrification. Climate adaptation strategies were underway, but mostly among farmers, ecologists, and non-governmental organizations (NGO) workers. (4) Discussion: This study helps inform elected officials, urban planners, and climate communicators as it relates to the allocation of resources for climate adaptation and education, and highlights key knowledge gaps that deserve focus by future outreach efforts. Full article