Showing papers in "Regional Environmental Change in 2020"

Regional climate downscaling over Europe: perspectives from the EURO-CORDEX community

Abstract: The European CORDEX (EURO-CORDEX) initiative is a large voluntary effort that seeks to advance regional climate and Earth system science in Europe. As part of the World Climate Research Programme (WCRP) - Coordinated Regional Downscaling Experiment (CORDEX), it shares the broader goals of providing a model evaluation and climate projection framework and improving communication with both the General Circulation Model (GCM) and climate data user communities. EURO-CORDEX oversees the design and coordination of ongoing ensembles of regional climate projections of unprecedented size and resolution (0.11° EUR-11 and 0.44° EUR-44 domains). Additionally, the inclusion of empirical-statistical downscaling allows investigation of much larger multi-model ensembles. These complementary approaches provide a foundation for scientific studies within the climate research community and others. The value of the EURO-CORDEX ensemble is shown via numerous peer-reviewed studies and its use in the development of climate services. Evaluations of the EUR-44 and EUR-11 ensembles also show the benefits of higher resolution. However, significant challenges remain. To further advance scientific understanding, two flagship pilot studies (FPS) were initiated. The first investigates local-regional phenomena at convection-permitting scales over central Europe and the Mediterranean in collaboration with the Med-CORDEX community. The second investigates the impacts of land cover changes on European climate across spatial and temporal scales. Over the coming years, the EURO-CORDEX community looks forward to closer collaboration with other communities, new advances, supporting international initiatives such as the IPCC reports, and continuing to provide the basis for research on regional climate impacts and adaptation in Europe.

Climate change vulnerability, water resources and social implications in North Africa

Abstract: North Africa is considered a climate change hot spot. Existing studies either focus on the physical aspects of climate change or discuss the social ones. The present article aims to address this divide by assessing and comparing the climate change vulnerability of Algeria, Egypt, Libya, Morocco, and Tunisia and linking it to its social implications. The vulnerability assessment focuses on climate change exposure, water resources, sensitivity, and adaptive capacity. The results suggest that all countries are exposed to strong temperature increases and a high drought risk under climate change. Algeria is most vulnerable to climate change, mainly due to the country’s high sensitivity. Across North Africa, the combination of climate change and strong population growth is very likely to further aggravate the already scarce water situation. The so-called Arab Spring has shown that social unrest is partly caused by unmet basic needs of the population for food and water. Thus, climate change may become an indirect driver of social instability in North Africa. To mitigate the impact of climate change, it is important to reduce economic and livelihood dependence on rain-fed agriculture, strengthen sustainable land use practices, and increase the adaptive capacity. Further, increased regional cooperation and sub-national vulnerability assessments are needed.

Climate change in the Eastern Amazon: crop-pollinator and occurrence-restricted bees are potentially more affected

Abstract: There is pressing need to anticipate the impacts of climate change on species and their functional contributions to ecosystem processes. Our objective is to evaluate the potential bee response to climate change considering (1) response traits—body size, nest site, and sociality; (2) contributions to ecosystem services (effect trait)—crop pollination; and (3) bees’ size of current occurrence area. We analyzed 216 species occurring at the Carajas National Forest (Eastern Amazon, Para, Brazil), using two different algorithms and geographically explicit data. We modeled the current occurrence area of bees and projected their range shift under future climate change scenarios through species distribution modeling. We then tested the relationship of potential loss of occurrence area with bee traits and current occurrence area. Our projections show that 95% of bee species will face a decline in their total occurrence area, and only 15 to 4% will find climatically suitable habitats in Carajas. The results indicate an overall reduction in suitable areas for all traits analyzed. Bees presenting medium and restricted geographic distributions, as well as vital crop pollinators, will experience significantly higher losses in occurrence area. The potentially remaining species will be the wide-range habitat generalists, and the decline in crop-pollinator species will probably pose negative impact on pollination service. The north of Para presented the greatest future climatic suitability and can be considered for conservation purposes. These findings emphasize the detrimental effects on biodiversity and agricultural production by climate change and provide data to support conservation planning.

Defining the solution space to accelerate climate change adaptation

Abstract: Decision makers need better insights about solutions to accelerate adaptation efforts. Defining the concept of solution space and revealing the forces and strategies that influence this space will enable decision makers to define pathways for adaptation action.

Determinants of food insecurity among smallholder farmer households in Central America: recurrent versus extreme weather-driven events

Abstract: To ensure food security among rural communities under a changing climate, policymakers need information on the prevalence and determinants of food insecurity, the role of extreme weather events in exacerbating food insecurity, and the strategies that farmers use to cope with food insecurity. Using household surveys in Guatemala and Honduras, we explore the prevalence of food insecurity among smallholder farmers on both a recurrent (seasonal) and episodic (resulting from extreme weather events) basis, analyze the factors associated with both types of food insecurity, and document farmer coping strategies. Of the 439 households surveyed, 56% experienced recurrent food insecurity, 36% experienced episodic food insecurity due to extreme weather events, and 24% experienced both types. Food insecurity among smallholder farmers was correlated with sociodemographic factors (e.g., age, education, migration) and asset ownership. The factors affecting food insecurity differed between type and prevalence of food insecurity. Our results highlight the urgent need for policies and programs to help smallholder farmers improve their overall food security and resilience to extreme weather shocks. Such policies should focus on enhancing farmer education levels, securing land tenure, empowering women, promoting generational knowledge exchange, and providing emergency food support in the lean season or following extreme weather events.

Dynamics and drivers of land use and land cover changes in Bangladesh

Abstract: Bangladesh has undergone dramatic land use and land cover changes (LULCC) in recent years, but no quantitative analysis of LULCC drivers at the national scale exists so far. Here, we quantified the drivers of major LULCC in combination with biophysical and socioeconomic observations at the sub-district level. We used Landsat satellite data to interpret LULCC from 2000 to 2010 and employed a Global Surface Water Dataset to account for the influences of water seasonality. The results suggest that major LULCC in Bangladesh occur between agricultural land and waterbodies and between forest and shrubland. Exclusion of seasonal waterbodies can improve the accuracy of our LULCC results and driver analysis. Although the gross gain and loss of agricultural land are large on the local scale, the net change (gross gain minus gross loss) at a country scale is almost negligible. Climate dynamics and extreme events and changes in urban and rural households were driving the changes from forest to shrubland in the southeast region. The conversion from agricultural land to standing waterbodies in the southwest region was mainly driven by urban household dynamics, population growth, distance to cities and major roads, and precipitation dynamics. This study, which is the first effort accounting for water seasonality and quantifying biophysical and socioeconomic drivers of LULCC at the national scale, provides a perspective on overall LULCC and underlying drivers over a decadal time scale and national spatial scale and can serve as a scientific basis for developing land policies in Bangladesh.

Earth Observation for agricultural drought monitoring in the Pannonian Basin (southeastern Europe): current state and future directions

Abstract: The Pannonian Basin in southeastern Europe is heavily used for rain-fed agriculture. The region experienced several droughts in the last years, causing major yield losses. Ongoing climate change, characterised by increasing temperatures and potential evapotranspiration, and by changes in precipitation distribution will likely increase the frequency and intensity of drought episodes in the future. Hence, ongoing monitoring of droughts and estimation of their impact on agriculture is necessary to adapt agricultural practices to changing weather and climate extremes. Several regional initiatives, projects and online tools have been established to facilitate drought monitoring and management in the Pannonian Basin. However, reliable systems to forecast potential drought impacts on plant productivity and agricultural yields at monthly to seasonal scales are only in their infancy, as plant response to climatic extremes is still poorly understood. With the increasing availability of high-resolution and long-term Earth Observation (EO) data and recent progress in machine learning and artificial intelligence, further improvements in drought monitoring and impact prediction capacities are expected. Here we review the current state of drought monitoring in the Pannonian Basin, identify EO-based variables to potentially improve regional drought impact monitoring and outline future perspectives for seasonal forecasts of drought impacts on agriculture.

Escalating environmental summer heat exposure—a future threat for the European workforce

Abstract: Heat exposure constitutes a major threat for European workers, with significant impacts on the workers’ health and productivity. Climate projections over the next decades show a continuous and accelerated warming over Europe together with longer, more intense and more frequent heatwaves on regional and local scales. In this work, we assess the increased risk in future occupational heat stress levels using the wet bulb globe temperature (WBGT), an index adopted by the International Standards Organization as regulatory index to measure the heat exposure of working people. Our results show that, in large parts of Europe, future heat exposure will indeed exceed critical levels for physically active humans far more often than in today’s climate, and labour productivity might be largely reduced in southern Europe. European industries should adapt to the projected changes to prevent major consequences for the workers’ health and to preserve economic productivity.

The relation of climate extremes with global warming in the Mediterranean region and its north versus south contrast

Abstract: This study uses the results of 28 CMIP5 global climate projections to link regional climate extremes in the Mediterranean region to the global mean annual surface temperature change. It shows that global warming will further increase the existing difference in intensity of precipitation and hydrological extremes between north and south Mediterranean areas (SMed and NMed, respectively), while the increase/decrease of warm/cold temperature extremes will be only marginally larger in the SMed. The Simple daily precipitation intensity index (SDII) and the total precipitation during very wet days (R95pTOT) are already larger in the NMed than in the SMed; they will increase with global warming at a rate of approximately 0.1 mm/K and 5 mm/K, respectively, in the NMed, with no significant change in the SMed. The maximum number of consecutive dry days (CDD) is already larger in the SMed than in the NMed and will increase more in the former than in the latter (rates are about 8 days/K and 5 days/K, respectively). Global warming will not affect the difference of maximum number of consecutive wet days (CWD), which is presently larger in the NMed than in the SMed and will decrease at a similar rate (about 0.5 days/K) in both areas. Changes of temperature extremes (warm nights, TN90p, and cold days, TX10p) will be similar in the north and south Mediterranean, though marginally larger in several areas of the SMed than in the NMed. Their increase will be dramatic and with a 4 K global warming almost all nights will be warm and there will be no cold days.

Climate change impacts on water resources in the Mediterranean

Abstract: More than ever, there is a need to understand and predict the trajectory of the environment and human societies in the prism of climate and its evolution in one of the most historyand biodiversity-rich regions. Indeed, global warming is occurring at a greater pace in the Mediterranean region than in other parts of the world, inducing marked changes in temperatures and precipitation but also other climate variables (Lionello and Scarascia 2018). There is a strong need to assess the potential impacts of this climate change in different sectors such as agriculture, energy production, or water resources but also their possible societal repercussions. In particular, for countries located in the south and east of the Mediterranean basin, the potential impacts can be very strong (Cramer et al. 2018). In this context, the MISTRALS (Mediterranean Integrated Studies at Regional and Local Scales) initiative was launched in 2008 and ended in 2020. The MISTRALS program was devoted to the study of the Mediterranean basin and its environment, with the objective to better understand the impact of global changes in this region and to anticipate its evolution over a century. More than 1000 scientists participate in the different MISTRALS programs, from different countries around the Mediterranean and spanning a great variety of scientific domains includingmarine and terrestrial ecosystems, fishing, climate, geology, agriculture, freshwater availability, economics, and sociology. This Topical Collection includes contributions from an international conference held in Montpellier, France, in October 2017. The goal of this conference was to present recent results on climate change impacts in the Mediterranean region produced within the various MISTRALS programs and also to improve the interactions between climate modelers and the different scientific communities working on climate change impacts. The papers of this Topical Collection are representative of the diversity of topics covered during the conference. They can be organized in three main categories: the first related to the sustainability of groundwater resources facing increasing aridity, the second about the main climate drivers and the third about their impacts on water resources and agriculture.

How warmer and drier will the Mediterranean region be at the end of the twenty-first century?

Abstract: Nearly all regions in the world are projected to become dryer in a warming climate Here, we investigate the Mediterranean region, often referred to as a climate change “hot spot” From regional climate simulations, it is shown that although enhanced warming and drying over land is projected, the spatial pattern displays high variability Indeed, drying is largely caused by enhanced warming over land However, in Northern Europe, soil moisture alleviates warming induced drying by up to 50% due to humidity uptake from land In already arid regions, the Mediterranean Sea is generally the only humidity source, and drying is only due to land warming However, over Sahara and the Iberian Peninsula, enhanced warming over land is insufficient to explain the extreme drying These regions are also isolated from humidity advection by heat lows, which are cyclonic circulation anomalies associated with surface heating over land The cyclonic circulation scales with the temperature gradient between land and ocean which increases with climate change, reinforcing the cyclonic circulation over Sahara and the Iberian Peninsula, both diverting the zonal advection of humidity to the south of the Iberian Peninsula The dynamics are therefore key in the warming and drying of the Mediterranean region, with extreme aridification over the Sahara and Iberian Peninsula In these regions, the risk for human health due to the thermal load which accounts for air temperature and humidity is therefore projected to increase significantly with climate change at a level of extreme danger

The interplay between structural flood protection, population density, and flood mortality along the Jamuna River, Bangladesh

Abstract: Levees protect floodplain areas from frequent flooding, but they can paradoxically contribute to more severe flood losses. The construction or reinforcement of levees can attract more assets and people in flood-prone area, thereby increasing the potential flood damage when levees eventually fail. Moreover, structural protection measures can generate a sense of complacency, which can reduce preparedness, thereby increasing flood mortality rates. We explore these phenomena in the Jamuna River floodplain in Bangladesh. In this study area, different levels of flood protection have co-existed alongside each other since the 1960s, with a levee being constructed only on the right bank and its maintenance being assured only in certain places. Primary and secondary data on population density, human settlements, and flood fatalities were collected to carry out a comparative analysis of two urban areas and two rural areas with different flood protection levels. We found that the higher the level of flood protection, the higher the increase of population density over the past decades as well as the number of assets exposed to flooding. Our results also show that flood mortality rates associated with the 2017 flooding in Bangladesh were lower in the areas with lower protection level. This empirical analysis of the unintended consequences of structural flood protection is relevant for the making of sustainable policies of disaster risk reduction and adaptation to climate change in rapidly changing environments.

The impact of climate change on a Mediterranean shallow lake: insights based on catchment and lake modelling

Abstract: Shallow lakes in the semi-arid climate zone of the Mediterranean are sensitive to drought due to the low annual precipitation and high evaporation. Changes in precipitation and temperature as projected by climate change scenarios will have an effect on the hydrology of these shallow lakes with secondary effects on nutrient dynamics and ecological state. In this study, we used a combined modelling approach that included the catchment model Soil and Water Assessment Tool (SWAT) and the lake model PCLake to study the possible effects of several climate scenarios on a shallow lake in semi-arid central Anatolia, Turkey. Our results show that lower precipitation and higher temperatures may reduce inflow rates and water levels drastically. Diffuse nutrient loading depended highly on precipitation and thus decreased as well. The lake model predicts an interaction between external nutrient loading and water levels. Low water levels benefited submerged macrophytes if nutrient concentrations were low, but low inflow rates and high evaporation during dry periods increased in-lake nutrient concentrations and chlorophyll-a. Cyanobacteria biomass was also higher in the drier and warmer scenarios. Overall, the results show that lower hydraulic loads and reduced flushing rates as a result of drier and warmer conditions lead to lower water levels and higher in-lake nutrient concentrations unless nutrient loading decreased as well. This implies that catchment-scale nutrient management is essential to maintain low nutrient concentrations in the lakes with increasing temperature and decreasing precipitation in a dry climate.

A typology of community flood resilience

Abstract: Flood risk is increasing worldwide and there is a growing need to better understand the co-benefits of investments in disaster resilience. Utilizing a multinational community flood resilience dataset, this paper takes a systems approach to understanding community-level flood resilience. Using a cluster analysis and bivariate correlation methods, we develop a typology of community flood resilience capacity based on community characteristics and five capitals (human, financial, natural, physical, and social). Our results reinforce the importance of context-specific policymaking and give recommendations of four distinct clusters to investigate the relationship between flood resilience and prevailing development conditions. We especially find that communities with higher interactions between their capital capacities tend to have higher flood resilience levels. Additionally, there are indications that stronger interactions between community capacities can help to induce multiple co-benefits when investing in disaster resilience. Our results also have important policy implications on the individual community level. For example, based on our results, we suggest that communities with lower flood resilience capacities and interactions can best build resilience on leveraging their relatively higher human capital capacities to strengthen the financial and social capitals. Negative effects might happen for urban communities when co-benefits of natural and physical capital are not fully integrated. The highest flood resilience capacity is found in communities with a well-balanced household income distribution which is likely a contributing factor to the importance of financial capital for this cluster. Our results emphasize the importance of an integrative approach to management when implementing systematic flood disaster resilience metrics and development measures.

Impacts of climate change on viticulture in Argentina

Abstract: Climate change is expected to impact considerably on viticultural zoning. In this work, impacts of future climate on Argentinean winegrowing regions are assessed using climatic projections from the IPSL-CM5A-MR model for the near (2015–2039) and the far (2075–2099) future under two emission scenarios (RCP4.5, RCP8.5). Four bioclimatic indices were assessed for exploring possible geographical shifts and suitability changes of Argentinean winegrowing regions. These geographical and suitability changes, assessed in terms of changes in vineyards location, varieties selection, and quality and quantity of grapevines, were considered as challenges and/or opportunities depending on the winegrowing region, the temporal horizon and the emission scenario. Results show a significant southwestward and higher altitude displacement of winegrowing regions, mainly for 2075–2099 under RCP8.5 scenario. Accordingly, the Argentinean viticulture may face both opportunities and/or challenges due to projected warmer climate conditions. Winegrowing regions of cold climates could be favoured, while winegrowing regions of warm climates could be disadvantaged, mainly for 2075–2099 under RCP8.5. Therefore, warmer climate conditions might be beneficial for maintaining the current grapevine varieties with their current grape quality or for cultivating new grapevine varieties in the new projected winegrowing areas; or they might be harmful for maintaining the current grapevine varieties with their yields and quality over most of current grapevine growing areas, but especially in the projected warmest ones. Summarizing, the results allow for understanding how temperature and precipitation changes could affect the future geographical distribution of Argentinean winegrowing areas and their suitability characteristics, useful information for planning adaptation in the coming decades.

Climate resilience of the top ten wheat producers in the Mediterranean and the Middle East

Abstract: Wheat is the main staple crop and an important commodity in the Mediterranean and the Middle East. These are among the few areas in the world where the climate is suitable for growing durum wheat but also are among the most rapidly warming ones, according to the available scenarios of climate projections. How much food security and market stability in the Mediterranean and the Middle East, both depending on wheat production and its interannual variability, are going to be compromised by global warming is an overarching question. To contribute in addressing it, we use a recently established indicator to quantify crop production climate resilience. We present a methodological framework allowing to compute the annual production resilience indicator from nonstationary time series. We apply this approach on the wheat production of the 10 most important producers in the Mediterranean and the Middle East. Our findings shows that if no adaptation will take place, wheat production reliability in the Mediterranean and the Middle East will be threatened by climate change already at 1.5 °C global warming. Average climate-related wheat production losses will exceed the worst past event even if the 2 °C mitigation target is met. These results call for urgent action on adaptation to climate change and support further efforts for mitigation, fully consistently with the Paris Agreement recommendations.

Participatory modelling for conceptualizing social-ecological system dynamics in the Bangladesh delta

Abstract: The concept of complex social-ecological systems (SES) as a means for capturing system dynamics properties (e.g. interactions and feedbacks) has gained attention in policymaking and advancing evidence in understanding complex systems. In contexts with limited data, conceptual system dynamic models offer a promising entry point to overcome challenges in understanding SES dynamics, which is essential for managing the long-term sustainability of SES and human wellbeing. Here, we build on previous work focused on agricultural production and use participatory approaches to develop a conceptual System Dynamics (SD) model for the south-west coastal SES in Bangladesh encompassing multiple forms of livelihood (fisheries, shrimp farming and forests, as well as agriculture). Using qualitative methods, including focus group discussions with farmers, fishermen, shrimp farmers and forest people, as well as expert consultations, we identified interactions, feedback loops and thresholds for the SES. The conceptual system model developed independently by stakeholders is consistent with a model developed using an empirical approach and literature review. Feedback loops are identified for the ecological (e.g. climate and water, mangrove and salinity) and social (e.g. shrimp farming and mangrove, agricultural (e.g. crops) production and subsidy) sub-systems in the Bangladesh delta. The biophysical thresholds that impact social conditions include river water discharge (1500 to 2000 m3 s−1), climate (28 °C) and soil salinity (~4 to ~10 dS m−1). Exceeding these thresholds suggests that SES may lose resilience in the near future and increase the likelihood of regime shifts. Findings of this study contribute to the management of the deltaic ecosystem and provide specific policy recommendations for improving environmental sustainability and human well-being in the Bangladesh delta and can be further used as inputs into system dynamic modelling to simulate changes in this SES.

Predicting impacts of climate variability on Banj oak ( Quercus leucotrichophora A. Camus) forests: understanding future implications for Central Himalayas

Abstract: Climate variability is one of the most powerful drivers that have resulted in loss of forest ecosystems. Quercus leucotrichophora (A. Camus) (Banj oak) is a keystone tree in moist temperate forests of Central Himalayas. Banj oak forests have high biodiversity, soil organic matter, and water holding capacity that supports human well-being. Climate variability coupled with anthropogenic pressure has affected the regeneration and succession patterns in these forests. Conservation of Banj oak is a socio-ecological challenge and will require an interdisciplinary approach. In the present study, we have assessed the impact of climate variability on the ecological niche of Q. leucotrichophora using the Maximum Entropy model (MaxEnt). The occurrence locations of the tree species were obtained from primary survey and published works (1984 to 2018). CMIP5 (Couple Model Inter-comparison Project)-derived bioclimatic variables were used as predictor variables in the modeling. The predictions were done following four IPCC RCP (Representative Concentration Pathway) scenarios for the future periods of 2050 and 2070. Our results show that the estimated potential habitats of the Q. leucotrichophora are likely to decline by 84–99%. Shift of the species from its present habitats due to climate variability reflects unusual patterns and demands climate adaptive management for forest landscape restoration (FLR) through active community involvement in the region. The study provides information about the suitable niches for the species of Banj oak forests and addresses the growing concern of spring-shed rejuvenation using climate adaptive FLR in Central Himalayas.

Extreme heat and drought in 1473 and their impacts in Europe in the context of the early 1470s

Abstract: Droughts and heatwaves are both dangerous natural hazards with a potential significant impact on human societies. In order to understand these hazards, it is important to examine such extreme events in the past. During the years 1471 to 1474, warm and dry weather conditions are described in most parts of Europe. Until now, these extraordinary years have not been examined in depth. Moreover, in spring 1473, a great drought and heat occurred in Europe. This heatwave facilitated a fast phenological development. During the summer and the autumn, temperatures were unusually high, and extremely dry weather conditions continued. In many places, the harvest began remarkably early, and there was abundant wine of a good quality. Fruit trees even bloomed for the second time in autumn. The heat and drought had a considerable impact on the environment and also caused damage to agriculture and society, including water shortages, harvest failures and rising food prices. The weather conditions of the years from 1471 to 1474 were outstanding during the fifteenth century and the heatwave and drought, as well as impacts on environment, economy, and society in the year 1473, were comparable to—if not more severe—than those in the year 1540. Learning from past climate anomalies like the 1473 drought in Europe is important for evaluating more recent and future climate extremes under increasing anthropogenic pressure.

Large zonal and temporal shifts in crops and cultivars coincide with warmer growing seasons in Finland

Abstract: In Finland, crop choices are limited, and cultivation is only possible in the regions where production risks and uncertainties are manageable. Climate change progresses rapidly at high latitudes and the thermal growing season is projected to become substantially longer in the future. This study aimed to monitor the regional shifts in major, secondary, minor and novel crops during 1996–2016 in Finland. We used long-term data from the Finnish Food Agency and evaluated changes in time to reach maturity of cultivars of model crops by using official variety trial data. Substantial changes were recorded in cultivation areas of crops, including expansion into new regions. Some of the traditional major crops such as oats (− 20%, i.e. − 75,700 ha from 1996 to 2016), barley (− 19%, − 105,700 ha) and potatoes (− 28%, − 4000 ha) have paved the way for emergent crops like faba beans (increase in area from 58 to 14,800 ha), peas (from 5700 to 13,400 ha), caraway (from 1900 to 18,400 ha) and spring oilseed rape (from 700 to 27,800 ha). Expansion per se was primarily enabled by climate warming, but success requires well-adapted cultivars, existing or emerging markets and industries or exports as well as motivating prices, policy support and valued ecosystem services.

Responses of soil nutrients to vegetation restoration in China

Abstract: Although vegetation restoration is known to improve soil quality and increase soil microbial activity, its effects on soil nutrients remain largely uncertain because of the complex relationship between plant growth and nutrient cycling. In order to evaluate the responses of soil nutrients to vegetation restoration, we used a standardized procedure to collect 586 and 395 observations for soil total nitrogen (TN) and total phosphorus (TP) in the top 30 cm of soil from 101 published field studies to conduct a meta-analysis in China. Our results revealed that soil TN and TP increased by 47% and 25% following vegetation restoration. Restoration actions made a larger contribution to recovery soil nutrients, and the recovery effects depended on land use history more than restoration approach and age. Vegetation restoration, especially on farmland with broadleaf species, could provide substantial opportunities for TN and TP sequestrations in the top 30 cm of soil. Passive approach (restoration by natural succession) performed better than active approach (restoration with human intervention) for enhancing soil TP content, but the recovery levels of soil TN were insignificantly different between two restoration approaches. Meanwhile, soil TN significantly increased with time after restoration. Soil nutrient dynamics were largely controlled by soil properties and were closely coupled with SOC stock dynamics. The magnitude and direction of the dynamics of soil TN and TP differed among four ecological regions, indicating geographical and climatic heterogeneities had significant impacts on soil nutrient recovery. Dynamics of soil nutrients were significantly influenced by soil properties, geographical locations, and climatic characteristics of the study sites, and these findings could facilitate priority setting and selection of treatment methods for vegetation restoration to enhance soil nutrients.

Machine learning for research on climate change adaptation policy integration: an exploratory UK case study

Abstract: Understanding how climate change adaptation is integrated into existing policy sectors and organizations is critical to ensure timely and effective climate actions across multiple levels and scales. Studying climate change adaptation policy has become increasingly difficult, particularly given the increasing volume of potentially relevant data available, the validity of existing methods handling large volumes of data, and comprehensiveness of assessing processes of integration across all sectors and public sector organizations over time. This article explores the use of machine learning to assist researchers when conducting adaptation policy research using text as data. We briefly introduce machine learning for text analysis, present the steps of training and testing a neural network model to classify policy texts using data from the UK, and demonstrate its usefulness with quantitative and qualitative illustrations. We conclude the article by reflecting on the merits and pitfalls of using machine learning in our case study and in general for researching climate change adaptation policy.

Multi-dimensional well-being associated with economic dependence on ecosystem services in deltaic social-ecological systems of Bangladesh

Abstract: While the benefits humans gain from ecosystem functions and processes are critical in natural resource-dependent societies with persistent poverty, ecosystem services as a pathway out of poverty remain an elusive goal, contingent on the ecosystem and mediated by social processes. Here, we investigate three emerging dimensions of the ecosystem service-poverty relationship: economic contribution of provisioning ecosystem services to the household livelihood mix, social-ecological systems producing different bundles of ecosystem services and material wealth versus reported life satisfaction. We analyse these relationships in Bangladesh, using data from a bespoke 1586-household survey, stratified by seven social-ecological systems in the delta coastal region. We create poverty lines to ensure comparability with traditional poverty measures that overlook environmental factors and subjective measurements of well-being. We find that any contribution of ecosystem service-based income to the livelihood mix decreases the likelihood of the incidence of poverty, and of individuals reporting dissatisfaction. We find no relationship between the incidence of material poverty and the specific social-ecological systems, from agriculture to fishery-dominated systems. However, the probability of the household head being dissatisfied was significantly associated with social-ecological system. Individuals living in areas dominated by export-oriented shrimp aquaculture reported lower levels of life satisfaction as an element of their perceived well-being. These results highlight the need for social policy on poverty that accounts for the diversity of outcomes across social-ecological systems, including subjective as well as material dimensions of well-being. National poverty reduction that degrades ecosystem services can have negative implications for the subjective well-being of local populations.

Contrasting development trajectories for coastal Bangladesh to the end of century

Abstract: Bangladesh is one of the most climate-sensitive countries globally, creating significant challenges for future development. Here we apply an integrated assessment model — Delta Dynamic Integrated Emulator Model (ΔDIEM) — to the south-west coastal zone of Bangladesh to explore the outcomes of four contrasting and plausible development trajectories under different climate and socio-economic scenarios: (1) embankment rehabilitation; (2) build elevation via controlled sedimentation; (3) planned migration (managed retreat) and (4) ‘do nothing’ (unplanned migration and abandonment). Embankment rehabilitation reduces flood risk, but at a high economic cost and enhancing waterlogging. Planned and unplanned migration combined with limited infrastructure management and governance both result in significant abandonment. Building elevation through sedimentation has the potential for increased environmental and economic sustainability but raises equity issues. Poverty and inequality persist across all scenarios, and outmigration from the coastal zone continues, although the magnitude is sensitive to assumptions about sea-level rise, socio-economic development and development trajectory. Integrated assessment tools linking the environment, people and policy choices, such as the ΔDIEM used here, highlight the complex interactions occurring in a dynamic delta environment. Such analysis supports informed management, development and adaptation.

Increased human pressures on the alpine ecosystem along the Qinghai-Tibet Railway

Abstract: Construction of the Qinghai-Tibet Railway (QTR) increased the links between inland China and the Qinghai-Tibet Plateau (QTP). The QTR accelerated surrounding tourism, boosted the local economy and led to rapid development of livestock raising. To assess how distance from the railway and different regions has influenced the impact of the QTR on the alpine ecosystem, human footprint maps were produced to indicate human pressures, and the normalized difference vegetation index (NDVI), an index of vegetation greenness, was used to characterize the growth of alpine vegetation. The construction and operation of the QTR have increased human pressures, while the establishment of nature reserves has effectively reduced human pressures. The QTR contributes significantly to the increased human pressures in the Tibetan region compared with the Qinghai region and exerts negative impacts on alpine vegetation. Although the warmer and wetter climate trend has proven beneficial in enhancing alpine vegetation greenness, the declining trend of alpine vegetation has been stronger in regions with more intensive human pressures, especially in the grazing areas and the tourist areas around Lhasa. These results suggest that the impact of the QTR on alpine vegetation in Tibet is greater than that in Qinghai and that the spatial extent of the indirect impact of the QTR in Tibet is confined to approximately 30 km from the railway. These results will provide guidance and a theoretical basis for the protection of the alpine environment on the QTP under intensified anthropogenic influence.

Understanding the economic impact of interacting carbon pricing and renewable energy policy in China

Abstract: Climate change is posing risks for human and natural systems, and one of the most important questions faced by policy makers is to reduce such risks and impacts through adaption and mitigation actions. As the country with the highest CO2 emissions, China is facing unprecedented challenges: climate change, energy structure transformation and socio-economic development all pose complex dilemmas for policy makers. The Chinese government has introduced energy policy and emission reduction measures to achieve its climate change mitigation targets. However, overlap between these measures may generate great uncertainty about their performance. By using a multi-regional computable general equilibrium (CGE) model, this study examines the economic impacts of implementing a nationwide carbon market and a renewable energy subsidy in the power sector in China. The study finds that a renewable energy policy would increase the economic cost of reducing greenhouse gas emissions and lead to a lower carbon price level if a carbon pricing mechanism were in place. However, the combination of the two policies indeed shows advantages in achieving emission reduction targets and renewable energy promotion targets. While an emission trading scheme is necessary for reducing emissions effectively, a renewable energy policy could promote the large-scale use of renewable energy in the electricity sector. In addition, the adoption of a renewable energy policy could yield substantial inter-regional capital inflow to central and western regions. This would improve low-carbon investment in less developed regions, and thus an appropriately designed policy mix would be sensible.

Community perception, adaptation and resilience to extreme weather in the Yucatan Peninsula, Mexico

Abstract: Perceptions of climate change, the impacts of and responses to climatic variability and extreme weather are explored in three communities in the Yucatan Peninsula, Mexico, in relation to livelihood resilience. These communities provide examples of the most common livelihood strategies across the region: small-scale fisheries (San Felipe) and semi-subsistence small-holder farming (Tzucacab and Calakmul). Although the perception that annual rainfall is reducing is not supported by instrumental records, changes in the timing of vital summer rainfall and an intensification of the mid-summer drought (canicula) are confirmed. The impact of both droughts and hurricanes on livelihoods and crop yields was reported across all communities, although the severity varied. Changes in traditional milpa cultivation were seen to be driven by less reliable rainfall but also by changes in Mexico’s agricultural and wider economic policies. Diversification was a common adaptation response across all communities and respondents, resulting in profound changes in livelihood strategies. Government attempts to reduce vulnerability were found to lack continuity, be hard to access and too orientated toward commercial scale producers. Population growth, higher temperatures and reduced summer rainfall will increase the pressures on communities reliant on small-scale farming and fishing, and a more nuanced understanding of both impacts and adaptations is required for improved livelihood resilience. Greater recognition of such local-scale adaptation strategies should underpin the developing Mexican National Adaptation Policy and provide a template for approaches internationally as adaptation becomes an increasingly important part of the global strategy to cope with climate change.

Determinants for decoupling economic growth from carbon dioxide emissions in China

Abstract: Understanding how CO2 emissions and economic growth can be decoupled and what drives this relationship is key to achieving long-term sustainable development. Current methods to decompose emissions and growth usually follow an approach known as the index decomposition method, which essentially decomposes changes in the Tapio decoupling elastic index (TDEI), a commonly used index describing the decoupling relationship, into different factors. However, in this method, it is difficult to separate technical efficiency from behavioral effects. To address this problem, we developed a novel decomposition approach by combining the TDEI with production-theoretical decomposition analysis. We then investigated the determinants for decoupling economic growth from CO2 emissions in China from 2011 to 2016. The results showed that (1) the overall decoupling states changed for different consecutive years in this period; (2) the decoupling states between economic growth and potential carbon factor, potential energy intensity, and energy usage technological change were negative factors while the decoupling states between economic growth and per capita GDP, population scale, CO2 emission technological change, technical efficiencies of energy usage, and CO2 emission were positive factors for the overall decoupling state; and (3) the differences in decoupling states were associated with the driving factors for changes in CO2 emissions. The variations in the decoupling states may partially be attributed to industrial structure, the efficiency of energy usage in provinces, and the “new normal” period in which the economic growth slows down. We advise fostering of diversified environment-friendly consumption hotspots.

Distribution of rose hip (Rosa canina L.) under current and future climate conditions

Abstract: This study aims to model the potential distribution areas of the species Rosa canina L. (rose hip) and to predict and analyse possible future changes in its distribution under given climate change scenarios. Nineteen bioclimatic variables from the WorldClim database were applied to 180 known species presence locations and the potential distribution area of the species under current conditions was identified using MaxEnt. To determine the future geographical distribution of the species under the impact of climate change, the Community Climate System Model (CCSM ver. 4) was used. The climate change scenarios were taken from the Representative Concentration Pathway (RCP) 4.5 and RCP 8.5 scenarios for 2050 and 2070 developed in line with the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. In addition, change analysis was carried out to identify the precise differences of area and location between the current and future potential distributions of the species, specifying habitat gains, habitat losses and stable habitats. Finally, a jackknife test was carried out to determine which individual bioclimatic variables affect the geographical distribution of the species the most. The study found that areas totalling 170,596 km2 are currently ‘highly suitable’ for Rosa canina L., but that this area will contract to 114,474 km2 by 2070 in the RCP 4.5 scenario and to 41,146 km2 by 2070 in the RCP 8.5 scenario. The mean temperature of the wettest quarter was the most influential bioclimatic variable affecting the distribution of the species.

Towards adaptation pathways for atoll islands. Insights from the Maldives

Abstract: Coastal areas host a significant part of the world population and of humankind’s adaptation needs in the face of effects of climate change, especially sea-level rise and ocean warming and acidification. Atoll islands illustrate frontline situations due to their biophysical (low elevation, small land area, 360°-exposure to waves, limited natural resources and fragile ecosystems) and human (high population densities in urban environments, low level of development, limited technical and financial capacities) characteristics. In these contexts, it is urgent to understand the space for societal adaptation and based on this, identify robust and context-specific adaptation strategies. This essay builds on the hypothesis that, given the nature of atoll islands, understanding the way and extent to which local human-driven disturbances affect the reef-island system’s capacity to provide coastal protection services, is a relevant entry point. Using the case of the Maldives, we propose to combine five types of adaptation into a generic adaptation pathway, and apply it to atoll island types going from no to highly disturbed environments. This work highlights two major conclusions: first, that diverse island profiles require different adaptation pathways; second, that in contexts under high human pressure, the window of opportunities for diversified adaptation strategies is closing fast.