Climate Adaptation Options Research Articles

Exploring smallholder farmers’ perceptions of climate change and its adaptation options in the Dire Dawa administration zone, Eastern Ethiopia

PurposeThis study aims to explore the smallholder farmers’ perceptions of climate change and its adaptation options (changing crop variety; improved crop and livestock; soil and water conservation [SWC]; and irrigation practices) and drought indices in the Dire Dawa Administration Zone, Eastern Ethiopia.Design/methodology/approachA cross-sectional household survey was used. A structured interview schedule for respondent households for key informants and focus group discussions were used. This study used both descriptive statistics and an econometric model. The model was used to compute the determinants of climate adaptation options in the study area. Drought characterization was carried out by DrinC software.FindingsThe results revealed households adapted to selected adaptation options. The model results confirmed that education level, farm size, tropical livestock units (TLUs) and access to agricultural extension services have positive and significant impacts on changing crop variety by 0.0014%, 0.045%, 0.032% and 0.035%, respectively. The likelihood of farmers’ decisions to use adaptation strategies (family size, TLU, agricultural extension service and distance from the market) has positive and significant impacts on SWC. The reconnaissance drought index (RDI6) of ONDJFM and AMJJAS showed extreme and severe drought index values of −2.88 and −1.96, respectively.Originality/valueThis study used a locally adopted climate change adaptation intervention for smallholder farmers, revealing the importance of drought characterization indices both seasonally and annually.

Investor value orientation and environmental and social implications: a case of New Zealand agribusinesses

PurposeThis study aims to examine the value orientations of New Zealand agribusiness investors and how these orientations influence their reactions to the environmental and social implications of agribusinesses.Design/methodology/approachIn the context of the New Zealand agricultural sector, the views of investors as published in print and broadcast media between 2018 and 2022 are gathered. The study uses qualitative content analysis to analyse the data. The study is based on the value-belief-norm theory.FindingsThe study reveals that New Zealand agribusiness investors express concern about the environmental (biospheric) and social (altruistic) impacts of the agribusiness sector, prompting calls for greater transparency, climate adaptation and ethical investment options. Additionally, they actively support local businesses to benefit their communities and preserve cultural heritage. Despite these biospheric and altruistic tendencies, investors also prioritise financial and non-financial interests (egoistic). This highlights a nuanced perspective guiding their investment choices – a balance between self-interest and contributing to the greater good. This signals a shift towards socially and environmentally responsible investment practices driven by multifaceted values.Research limitations/implicationsThe findings of this study highlight the role of non-pecuniary motives, like values, in determining the relevance of environmental and social information.Practical implicationsThe study’s findings offer insight to agribusinesses on how investors’ value orientations shape their investment decisions. This understanding can guide businesses in framing a reporting strategy that enhances the likelihood of investors perceiving reporting as relevant and persuasive, thereby attracting more investments. In turn, this tailored reporting approach assists investors in making well-informed decisions in assessing the environmental and societal risks of agribusinesses.Originality/valueThe study offers a framework explaining how agribusinesses can increase the likelihood of investors finding firms reporting relevant and persuasive, leading to increased investments in environmentally and socially sustainable practices.

Prioritising climate adaptation options to minimise financial and distributional impacts of water supply disruptions

Climate-related disruptions to water supply infrastructure services incur direct financial losses to utilities (e.g. to repair damaged assets) and externalise a societal cost to domestic customers due to additional costs that they may incur (e.g. to acquire water from alternative sources). The latter often represents an uncompensated social burden, which should be properly accounted for in investment planning. Here we present a new framework for quantifying direct financial risks burdened by utilities and alternative water purchase losses incurred by domestic customers, including those in low-income groups, during flood- and drought-induced utility water supply disruptions. This framework enables the comparison of benefit-cost ratios of a portfolio of flood protection and leakage reduction for water supply systems across the island of Jamaica. A system-level optioneering analysis allows the identification of the optimal adaptation option per system. We estimate that 34% of systems would benefit from flood defences and 53% would benefit from leakage reduction to adaptation to droughts. The benefit that could be achieved by implementing all system optimised adaptation options is estimated to be 720 million Jamaican dollars per year on average, representing a substantial saving for the utility and its customers, including low-income customers. We identify options that offer strong synergies between economic and equity objectives for both types of adaptation option. The proposed framework is established to support the business case for climate adaptation in the water supply sector and to prioritise across flood and drought mitigation options. We take a first step towards mainstreaming equity considerations in water supply sector optioneering frameworks by estimating the contribution of adaptation options towards reducing household costs for low-income customers.

Comparative assessment of farmers’ perceptions on climate change: Experiences from semi-arid tropics of India

The present study was conducted to assess farmers' perceptions of the effects of climate change on their livelihoods. The aim was to compare these perceptions regarding climate trends, related effects, and adaptation options among rural communities in three Semi-Arid Tropical (SAT) villages located in Maharashtra and Andhra Pradesh, representing different agro-ecological regions. This study employed both quantitative and qualitative research methods to elicit farmers' perceptions, including farm household surveys, focus group discussions, and key informant interviews. The results of the study indicate that farm households are aware of climate change and are particularly concerned about changes in rainfall patterns and increased frequency of drought events, both in inter-seasonal and intra-seasonal distribution. Among the studied villages, Dokur experienced the most severe impacts from these changes. Furthermore, farmers perceive that natural resources such as land, water, and biodiversity have been affected due to the variations in the climate. In response to these challenges, farmers have adopted a set of adaptation options, including changes in crop selection, land management, water usage, socio-economic strategies, and collective actions. However, the study found discouraging trends in the adoption of these adaptation options, primarily due to a range of barriers that hinder their ability to adapt efficiently to climate change. This study underscores the critical need for region-specific strategic research and development programs aimed at enhancing the biophysical and socioeconomic conditions of these rural areas. Such efforts would enable these communities to improve their adaptive capacity and livelihood resilience in the face of climate-related risks and impacts. Future policies and programs should prioritize the upliftment of these fragile SAT communities, with the goal of enhancing their resilience to climate change and improving their overall quality of life.

Local and regional climate trends and variabilities in Ethiopia: Implications for climate change adaptations

Ethiopia is experiencing considerable impact of climate change and variability in the last five decades. Analyzing climate trends and variability is essential to develop effective adaptation strategies, particularly for countries vulnerable to climate change. This study analyzed trends and variabilities of climate (rainfall, maximum temperature (Tmax), and minimum temperature (Tmin)) at local and regional scales in Ethiopia. The local analysis was carried out considering each meteorological station, while the regional analyses were based on agro-ecological zones (AEZs). This study used observations from 47 rainfall and 37 temperature stations obtained from the Ethiopian Meteorological Institute (EMI) for the period of 1986 to 2020. The Modified Mann-Kendall (MMK) trend test and Theil Sen's slope estimator were used to analyze the trends and magnitudes of change, respectively, in rainfall as well as temperature. The coefficient of variation (CV) and standardized anomaly index (SAI) were also employed to evaluate rainfall and temperature variabilities. The local level analysis revealed that Bega (dry season), Kiremt (main rainy season), and annual rainfall showed increasing trend, albeit no significant, in most stations, but the rainfall in Belg (small rainy) season showed a non-significant decreasing trend. The regional levels analysis also indicated an increasing trend of Bega, Kiremt, and annual rainfall in most AEZs, while Belg rainfall showed a decreasing trend in the greater number of AEZs. The result of both local and regional levels of analysis discerned a spatially and temporally more homogeneous warming trend. Both Tmax and Tmin revealed an increasing trend in annual and seasonal scales at most meteorological stations. Likewise, an increase was recorded for mean Tmax and Tmin in entire/most AEZs. The observed trends and variabilities of rainfall and temperature have several implications for climate change adaptations. For example, the decrease in Belg rainfall in most AEZs would have a negative impact on areas that heavily depend on Belg season's rainfall for crop production. Some climate adaptation options include identifying short maturing crop varieties, soil moisture conservation, and supplemental irrigation of crops using harvested water during the main rainy season. Conversely, since the first three months of Bega season (October to December) are crop harvest season in most parts of Ethiopia, the increase in Bega rainfall would increase crop harvest loss, and hence, early planting date and identifying short maturing crops during the main rainy season are some climate adaptation strategies. Because of the increase in temperature, water demand for irrigation during Bega season will increase due to increased evapotranspiration. On the other hand, the increase in Kiremt rainfall can be harvested and used for supplemental irrigation during Bega as well as the small rainy season, particularly for early planting. In view of these findings, it is imperative to develop and implement effective climate-smart agricultural strategies specific to each agro-ecological zone (AEZ) to adapt to rainfall and temperature changes and variabilities.

Co-Cultivation and Matching of Early- and Late-Maturing Pearl Millet Varieties to Sowing Windows Can Enhance Climate-Change Adaptation in Semi-Arid Sub-Saharan Agroecosystems

In semi-arid regions, climate change has affected crop growing season length and sowing time, potentially causing low yield of the rainfed staple crop pearl millet (Pennisetum glaucum L.) and food insecurity among smallholder farmers. In this study, we used 1994–2023 rainfall data from Namibia’s semi-arid North-Central Region (NCR), receiving November–April summer rainfall, to analyze rainfall patterns and trends and their implications on the growing season to propose climate adaptation options for the region. The results revealed high annual and monthly rainfall variabilities, with nonsignificant negative trends for November–February rainfalls, implying a shortening growing season. Furthermore, we determined the effects of sowing date on grain yields of the early-maturing Okashana-2 and local landrace Kantana pearl millet varieties and the optimal sowing window for the region, using data from a two-year split-plot field experiment conducted at the University of Namibia—Ogongo Campus, NCR, during the rainy season. Cubic polynomial regression models were applied to grain-yield data sets to predict grain production for any sowing date between January and March. Both varieties produced the highest grain yields under January sowings, with Kantana exhibiting a higher yield potential than Okashana-2. Kantana, sown by 14 January, had a yield advantage of up to 36% over Okashana-2, but its yield gradually reduced with delays in sowing. Okashana-2 exhibited higher yield stability across January sowings, surpassing Kantana’s yields by up to 9.4% following the 14 January sowing. We determined the pearl millet optimal sowing window for the NCR to be from 1–7 and 1–21 January for Kantana and Okashana-2, respectively. These results suggest that co-cultivation of early and late pearl millet varieties and growing early-maturing varieties under delayed seasons could stabilize grain production in northern Namibia and enhance farmers’ climate adaptation. Policymakers for semi-arid agricultural regions could utilize this information to adjust local seed systems and extension strategies.

Tracking climate change adaptation in Eastern Africa: integrating governmental and livestock keeper perspectives

ABSTRACT Adaptation tracking is crucial for understanding progress in responding to climate change impacts across space and time. However, adaptation tracking is constrained by the lack of agreement on how to measure adaptation. While there has been significant focus on government plans and other documented adaptation as the basis for adaptation tracking, emerging literature also advocates for inclusive approaches that consider multiple experiences and priorities when designing and using adaptation tracking indicators. However, little literature empirically investigates the specifics of what this integrated approach is or what it could achieve. We address this gap using a thematic analysis of 48 focus group discussions and of government policies to compare the perspectives of livestock keepers and governments in Eastern Africa on climate risks and adaptation in livestock systems. The results show considerable similarities in how they perceive climatic hazards, impacts, adaptation strategies, goals, and adaptive capacities, highlighting elements that could be recognized as relevant by both sets of stakeholders. However, the differences underscore the value of an integrated approach as it supports the recognition of variations in climate risks and adaptation options across contexts as well as capturing diverse effects of adaptation across scales. Insights from this paper contribute to discussions on developing integrated adaptation tracking frameworks that take into account the contextual nature of climate hazards, impacts, adaptation strategies, adaptive capacities, and adaptation goals. Key policy insights Governments and livestock keepers perceive climate hazards, impacts, adaptation strategies, adaptive capacity, and adaptation goals in largely similar ways. Differences in governmental and livestock keeper perspectives provide the basis for integrating them in the development of adaptation tracking indicators. Drawing on multiple experiences, priorities, and knowledges could support more effective tracking of adaptation progress by considering the various scales and contexts within which adaptation occurs. Integration requires an adaptation tracking framework that utilizes core indicators that have broader relevance and additional ones that address the context-specificity of climate hazards, impacts, adaptive capacities, adaptation strategies, and adaptation goals.

Climate analogs can catalyze cross-regional dialogs for US specialty crop adaptation

Communication theory suggests that interactive dialog rather than information transmission is necessary for climate change action, especially for complex systems like agriculture. Climate analogs—locations whose current climate is similar to a target location’s future climate—have garnered recent interest as transmitting more relatable information; however, they have unexplored potential in facilitating meaningful dialogs, and whether the way the analogs are developed could make a difference. We developed climate context-specific analogs based on agriculturally-relevant climate metrics for US specialty crop production, and explored their potential for facilitating dialogs on climate adaptation options. Over 80% of US specialty crop counties had acceptable US analogs for the mid-twenty-first century, especially in the West and Northeast which had greater similarities in the crops produced across target-analog pairs. Western counties generally had analogs to the south, and those in other regions had them to the west. A pilot dialog of target-analog pairs showed promise in eliciting actionable adaptation insights, indicating potential value in incorporating analog-driven dialogs more broadly in climate change communication.

Why “formal” climate adaptation strategies fail in sub‐Saharan Africa: Ignoring adapters’ agency in the case of smallholding agriculture farming practices in Bono East Region of Ghana

AbstractThis paper reviewed a body of literature on climate adaptation options in sub‐Saharan Africa's (SSA) smallholding agriculture and complemented it with a case study involving experts interviews, focus group discussions, large‐scale household surveys, and farmer practices observation while drawing insight from the concept of “everyday adaptation and interrupted agency” and agency theory to assess farmer perceived limitations with climate‐smart agriculture (CSA) and climate‐wise food systems (CWFS) practices for climate adaptation in the SSA. The study noted that the narrow focus on CSA and/or CWFS as a silver bullet for climate change adaptation suitable for smallholding agriculture ignores food producers’ agency to undermine sustainable and inclusive adaptation solutions. Moreover, smallholder farmers’ everyday climate adaptation practices could be grouped into three categories; on‐farm adaptation, off‐farm adaptation, and Indigenous agroecological adaptation options. The on‐farm adaptation options are usually agriculture intensification and extensification. The off‐farm adaptation options include livelihood diversification activities, petty trading, seasonal labor jobs, and migration. The Indigenous agroecological adaptation strategy uses observing nature and weather elements to predict the onset of the rainy season. The study noted that smallholders’ adaptation options, which is an expression of their agency, are motivated by smallholders’ desire to be resilient to changing climate, increase productivity and income, and social network influence but not necessarily because the strategy is being promoted by the government or Non‐Governmental Organizations (NGOs). Therefore, we propose a sustainable food agency (SFA)—a multifaceted blended constellation of climate adaptation and mitigation strategies, as the best approach to addressing the climate crises in the SSA. The SFA allows individuals or groups to decide what climate change adaptation options best work for them to adapt to changing climate and produce and distribute their food without undermining the economic, social, and environmental bases that generate food security and nutrition for present and future generations.

Climate Resilient Water Management for Sustainable Agriculture

The management of water resources in both irrigated and rain-fed agriculture is becoming an increasingly complex worldwide due to anticipated water scarcity, and compounded by the challenges of global warming and climate change. Climate-smart water technologies viz. Drip irrigation, Central pivot irrigation, Hydrogel and SWAT method need to be judiciously applied to overcome these challenges. Agriculture is a critical sector in India and other developing countries, providing substantial employment opportunities to rural populations and supporting efforts to achieve food and nutritional security. This paper addresses the challenge of increasing food production and improving rural livelihoods while safeguarding critical water resources for sustainable use, particularly in drought-prone regions, through adaptive measures for effective water management. An integrated approach is necessary for agricultural water management through the adoption of innovative technologies such as water harvesting, micro-irrigation, and resource conservation farming to increase water-use efficiency in agriculture and other critical services to humans and animals. The study aims to enhance understanding of the potential implications of climate change and adaptation options for agricultural water management, thereby enabling them to take up adaptation challenges and develop measures to reduce the farming sector's vulnerability to climate change.

Effects of Climate Change on Streamflow in the Ayazma River Basin in the Marmara Region of Turkey

This study investigates the effects of climate change on streamflow in the Ayazma river basin located in the Marmara region of Turkey using a hydrological model. Regional Climate Model (RCM) outputs from CNRM-CM5/RCA4, EC-EARTH/RACMO22E and NorESM1-M/HIRHAM5 with the RCP4.5 and RCP8.5 emission scenarios were utilized to drive the HBV-Light (Hydrologiska Byråns Vattenbalansavdelning) hydrological model. A trend analysis was performed with the Mann–Kendall trend test for precipitation and temperature projections. A meteorological drought assessment was presented using the Standardized Precipitation–Evapotranspiration Index (SPEI) method for the worst-case scenario (i.e., RCP8.5). The calibrated and validated hydrological model was used for streamflow simulations in the basin for the period 2022–2100. The selected climate models were found to produce high precipitation projections with positive anomalies ranging from 22 to 227 mm. The increase in annual mean temperatures reached up to 1.8 °C and 2.6 °C for the RCP4.5 and RCP8.5 scenarios, respectively. The trend results showed statistically insignificant upward and downward trends in precipitation and statistically significant upward trends in temperatures at 5% significance level for both RCP scenarios. It was shown that there is a significant increase in drought intensities and durations for SPEI greater than 6 months after mid- century. Streamflow simulations showed decreasing trends for both RCP scenarios due to upward trend in temperature and, hence, evapotranspiration. Streamflow peaks obtained with the RCP8.5 scenario were generally lower than those obtained with the RCP4.5 scenario. The mean values of the streamflow simulations from the CNRM-CM5/RCA4 and NorESM1-M/HIRHAM5 outputs were approximately 2 to 10% lower than the observation mean. On the other hand, the average value obtained from the EC-EARTH/RACMO 22E outputs was significantly higher than the observation average, up to 32%. The results of this study can be useful for evaluating the impact of climate change on streamflow and developing sustainable climate adaptation options in the Ayazma river basin.

Coastal Defense Megaprojects in an Era of Sea-Level Rise: Politically Feasible Strategies or Army Corps Fantasies?

Storm surge barriers, levees, and other coastal flood defense megaprojects are currently being proposed as strategies to protect several US cities against coastal storms and rising sea levels. However, social conflict and other political factors add a layer of complexity that casts doubt on their status as practical climate adaptation options. The specific mechanisms responsible for some projects not progressing beyond initial planning stages remains unclear. In this study, we examined the outcome of two USACE storm surge barrier proposals to explore the political reasons why some coastal flood protection megaprojects break ground in the US, while others do not. Using original archive research, we concluded that storm surge barriers are politically challenging climate adaptation options because of modern environmental laws that provide avenues for expression of oppositional views within the decision process and the allure of alternative options that are more aesthetically pleasing and cheaper and faster to implement. To better allocate public resources and utilize the expertise of USACE, future flood protection megaprojects should first achieve broad support from the public, nongovernmental organizations (NGOs), and elected officials before beginning serious planning. This support could be achieved through new innovative designs that simultaneously address adverse environmental impacts and provide cobenefits (e.g., recreation). New designs should be studied to better understand the level of protection offered and their associated reliability so that USACE has confidence in their use.

Climate impacts in sport: extreme heat as a climate hazard and adaptation options

ABSTRACT Rationale The aim of this paper is to present research examining how the climate hazard of extreme heat impacts varsity-level sport athletes and facilities, current responses, and options for adaptation. Methods A sample of 30 participants from a higher education institution athletics department was used with a two-phase Delphi study method that applied two iterations of questionnaires and mixed method analysis. The institution was situated in a region with a Köppen classification of “Warm Summer Continental Climate”. Findings Heat hazards aligned primarily with slow-onset, rather than fast-onset, climate impact categories. Adapting to heat hazards aligned with incremental adaptation rather than transformative adaptation. These findings suggest climate adaptation is a new concept for university sport and so is at a pioneering stage of practice. Practical implications Identifies options for sport managers for integrating adaptation into the strategic and operational thinking of sport organizations. Research contribution This paper extends knowledge by presenting evidence of heat risks to the sport as perceived by sport managers and participants during an era of climate change. The results address gaps in the existing literature by using primary source data to add to the evidence base for sport and climate change, and by identifying options for climate adaptation.

Climate adaptation options for the 2026 Basin Plan: opportunities for managing climate risk

ABSTRACT How water resources are defined, both conceptually and legally, is central to their efficient and equitable allocation. With climate change introducing significant uncertainties to water resources management, flexible allocation frameworks are needed that can adapt to changing conditions. This paper explores options for climate-adaptive water allocation in Australia’s Murray Darling Basin. The 2026 revision of the Basin Plan may provide significant opportunities for proactive climate risk mitigation, but this depends on rigorous evaluation of policy options. The Water Act requires that the Plan’s revisions use the best available science to inform strategies that minimise the impact of climate risks. The Act also enables the use of ratios and formulas as alternatives to using long-term averages as the basis of the Plan. However, there have been limited investigations into using these alternatives. Achieving more adaptive policies depends on rigorously assessing climate risk management options. Given the far-reaching consequences of climate change, rigorous investigations are needed into reforms to the established approaches to water resources planning and to existing water entitlements and allocation regimes. At minimum, this means reassessing the total resource pool and all subsidiary targets and investigating allocation frameworks that equitably share risks between extractive users and the environment.

Future trends in compound concurrent heat extremes in Swiss cities - An assessment considering deep uncertainty and climate adaptation options

The interaction of multiple hazards across various spatial and temporal scales typically causes compound climate and extreme weather events. Compound concurrent hot day and night (CCHDNs) extremes that combine daytime and nighttime heat are of greater concern for health than individual hot days (HDs) or hot nights (HNs), even though their frequency is lower. We utilize a bottom-up exploratory approach to investigate how adaptation options and various unfolding future scenarios alleviate the impacts of the heatwaves and affect the frequency and intensity of CCHDNs. We use climate observations (1981–2020) and Switzerland's future climate model scenarios (CH2018) to analyze historical and future trends of the individual hot day followed by a hot night (HDNs, first metric), and the length and frequency of CCHDNs (second and third metrics) in the near-future (2020–2050) and far-future (2070–2100). Results show more frequent and lengthier HDNs in cities under all emission scenarios, notably significant under high emissions scenarios. The highest increase of HDNs occur in i) Lugano with 65.8 days (decade−1) in the historical period and 110 (371) days (decade−1) in near-future (far-future), ii) Geneva with historical 48 days (decade−1) to 108 (362) (decade−1), iii) Basel with 48–74 (217) days in the future, followed by iv) Bern with 15–44 (213) days and v) Zürich with 14–50 (217) days (decade−1) in the near-future and far-future, respectively. We consistently project that the CCHDNs in April–October become more likely and intense in all cities under all emission scenarios, with higher increases under the RCP8.5 scenario and after the 2050s. The frequency of compound extreme heatwaves (exceeding both historical thresholds of night and day temperatures) may increase by 3.5–7.8-fold and become 3.3–5.3-fold lengthier in all cities of Switzerland in the far-future. We find that the adaptation options targeting higher tolerance to increased minimum temperatures contribute more to reducing compound extreme events' frequency and intensity than adaptation options that address the maximum daily temperature.

Integrating justice in Nature-Based Solutions to avoid nature-enabled dispossession

Heavily featured over the last few years in global research and policy agreements, Nature-Based Solutions (NBS) remain however exposed to much debate over the ways their current design and ability to achieve both environmental goals and social needs. As they become mainstream climate mitigation and adaptation options, their capacity to deliver expected benefits, especially when contemplating equity and justice, is at least uncertain. Through a critical review of existing debates and perspectives on NBS, this paper questions their uptake and points at the frequent embeddedness of NBS in speculative and elite-based development paths in both urban and rural areas. We present an alternative, justice-oriented approach to NBS so that projects can avoid nature-enable dispossession and instead build nature-inspired justice that prioritizes the needs, identities, and livelihoods of the most ecologically and socially vulnerable residents.

Future Trends in Compound Heat Extremes in Swiss Cities - an Assessment Considering Deep Uncertainty and Climate Adaptation Options

Future Trends in Compound Heat Extremes in Swiss Cities - an Assessment Considering Deep Uncertainty and Climate Adaptation Options

Projecting global mariculture production and adaptation pathways under climate change.

The sustainability of global seafood supply to meet increasing demand is facing several challenges, including increasing consumption levels due to a growing human population, fisheries resources over-exploitation and climate change. Whilst growth in seafood production from capture fisheries is limited, global mariculture production is expanding. However, climate change poses risks to the potential seafood production from mariculture. Here, we apply a global mariculture production model that accounts for changing ocean conditions, suitable marine area for farming, fishmeal and fish oil production, farmed species dietary demand, farmed fish price and global seafood demand to project mariculture production under two climate and socio-economic scenarios. We include 85 farmed marine fish and mollusc species, representing about 70% of all mariculture production in 2015. Results show positive global mariculture production changes by the mid and end of the 21st century relative to the 2000s under the SSP1-2.6scenario with an increase of 17%±5 and 33%±6, respectively. However, under the SSP5-8.5scenario, an increase of 8%±5 is projected, with production peaking by mid-century and declining by 16%±5 towards the end of the 21st century. More than 25% of mariculture-producing nations are projected to lose 40%-90% of their current mariculture production potential under SSP5-8.5 by mid-century. Projected impacts are mainly due to the direct ocean warming effects on farmed species and suitable marine areas, and the indirect impacts of changing availability of forage fishes supplies to produce aquafeed. Fishmeal replacement with alternative protein can lower climate impacts on a subset of finfish production. However, such adaptation measures do not apply to regions dominated by non-feed-based farming (i.e. molluscs) and regions losing substantial marine areas suitable for mariculture. Our study highlights the importance of strong mitigation efforts and the need for different climate adaptation options tailored to the diversity of mariculture systems, to support climate-resilient mariculture development.

Systematic mapping of global research on climate and health: a machine learning review

SummaryBackgroundThe global literature on the links between climate change and human health is large, increasing exponentially, and it is no longer feasible to collate and synthesise using traditional systematic evidence mapping approaches. We aimed to use machine learning methods to systematically synthesise an evidence base on climate change and human health.MethodsWe used supervised machine learning and other natural language processing methods (topic modelling and geoparsing) to systematically identify and map the scientific literature on climate change and health published between Jan 1, 2013, and April 9, 2020. Only literature indexed in English were included. We searched Web of Science Core Collection, Scopus, and PubMed using title, abstract, and keywords only. We searched for papers including both a health component and an explicit mention of either climate change, climate variability, or climate change-relevant weather phenomena. We classified relevant publications according to the fields of climate research, climate drivers, health impact, date, and geography. We used supervised and unsupervised machine learning to identify and classify relevant articles in the field of climate and health, with outputs including evidence heat maps, geographical maps, and narrative synthesis of trends in climate health-related publications. We included empirical literature of any study design that reported on health pathways associated with climate impacts, mitigation, or adaptation.FindingsWe predict that there are 15 963 studies in the field of climate and health published between 2013 and 2019. Climate health literature is dominated by impact studies, with mitigation and adaptation responses and their co-benefits and co-risks remaining niche topics. Air quality and heat stress are the most frequently studied exposures, with all-cause mortality and infectious disease incidence being the most frequently studied health outcomes. Seasonality, extreme weather events, heat, and weather variability are the most frequently studied climate-related hazards. We found major gaps in evidence on climate health research for mental health, undernutrition, and maternal and child health. Geographically, the evidence base is dominated by studies from high-income countries and China, with scant evidence from low-income counties, which often suffer most from the health consequences of climate change.InterpretationOur findings show the importance and feasibility of using automated machine learning to comprehensively map the science on climate change and human health in the age of big literature. These can provide key inputs into global climate and health assessments. The scant evidence on climate change response options is concerning and could significantly hamper the design of evidence-based pathways to reduce the effects on health of climate change. In the post-2015 Paris Agreement era of climate solutions, we believe much more attention should be given to climate adaptation and mitigation options and their effects on human health.FundingForeign, Commonwealth & Development Office.

Territorial governance of managed retreat in Sweden: addressing challenges

Many climate adaptation options currently being discussed in Sweden to meet the challenge of surging seas and inland flooding advocate holding the line through various hard and soft measures to stabilize the shoreline, while managed retreat is neither considered as feasible option nor has it been explicitly researched in Sweden. However, failure to consider future flooding from climate change in municipal planning may have dangerous and costly consequences when the water does come. We suggest that managed retreat practices are challenging in Sweden, not only due to public opinions but also because of a deficit of uptake of territorial knowledge by decision-makers and difficulties in realizing flexible planning options of the shoreline. A territorial governance framework was used as a heuristic to explore the challenges to managed retreat in four urban case studies (three municipalities and one county) representing different territorial, hydrological and oceanographic environments. This was done through a series of participatory stakeholder workshops. The analysis using a territorial governance framework based on dimensions of coordination, integration, mobilization, adaptation and realization presents variations in how managed retreat barriers and opportunities are perceived among case study sites, mainly due to the differing territorial or place-based challenges. The results also indicate common challenges regardless of the case study site, including coordination challenges and unclear responsibility, the need for integrated means of addressing goal conflicts and being able to adapt flexibly to existing regulations and plans. Yet rethinking how managed retreat could boost community resilience and help to implement long-term visions was seen as a way to deal with some of the territorial challenges.