In this study, the electric field and the particle precipitation at different spatial scale sizes have been investigated by utilizing the Dynamic Explorer 2 satellite data set, focusing on conditions ...of moderately strong southward interplanetary magnetic field. Dynamic Explorer 2 data from the period between 1981 and 1983, from all universal times, seasons, and both hemispheres, have been processed and binned over geomagnetic latitude and local time. It is found that, as compared with the large‐scale (>500 km) average electric field and particle precipitation, the variabilities (i.e., departures from the large‐scale average) of electric field and particle precipitation are not negligible. Moreover, the electric field variability tends to be anticorrelated with the particle precipitation variability in the auroral regions on small scale and mesoscale (<500 km). The impacts associated with the small‐scale and mesoscale electric field and particle precipitation variabilities on Joule heating have also been addressed in this study by using the Global Ionosphere and Thermosphere Model. It is found that although Joule heating can be significantly enhanced by the small‐scale and mesoscale electric field variabilities (~27% globally), the corresponding change in the particle precipitation tends to depress such enhancement (−5% globally), which is not negligible on the dusk side (up to −17.5% locally). It is the first time that the correlation between electric field and particle precipitation variabilities on small scale and mesoscale has been quantified. Furthermore, the impact on Joule heating associated with the correlation between the small‐scale and mesoscale electric field and particle precipitation variabilities has been evaluated unprecedentedly in a general circulation model.
Plain Language Summary
At high latitudes, the electromagnetic energy from the magnetosphere dissipates into Earth's upper atmosphere, leading to both local and global changes. The accuracy of numerical simulation of Earth's upper atmosphere depends on the accuracy of the estimation of such energy input or heating, which is always challenging. The heating is closely related with the ionospheric electric field and precipitating particles from the magnetosphere. Part of the difficulty of determining the heating is that the knowledge about their structures below the model resolution (i.e., small‐scale and mesoscale variabilities) is still limited, especially about their correlation. Therefore, it is still unclear to what extent such correlation can impact the heating estimation. In this study, the correlation between small‐scale and mesoscale electric field and particle precipitation variabilities has been quantified for the first time by utilizing satellite observations. Furthermore, the impact of small‐scale and mesoscale variabilities and their correlation on the heating estimation has been evaluated unprecedentedly using a general circulation model. It is found that there can be a large localized overestimation of heating if the correlation between small‐scale and mesoscale electric field and particle precipitation variabilities is neglected. Our results can be useful for the improvement of numerical models of Earth's upper atmosphere and important for magnetosphere‐ionosphere coupling studies.
Key Points
The electric field and particle precipitation variabilities at high latitudes have been quantified
The variable electric field is anticorrelated with the variable particle precipitation on small scale and mesoscale
The reduction of Joule heating due to the anticorrelation between the small‐scale and mesoscale electric field and particle precipitation variabilities is not negligible
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Small‐scale fisheries through the wellbeing lens Weeratunge, Nireka; Béné, Christophe; Siriwardane, Rapti ...
Fish and fisheries (Oxford, England),
June 2014, Volume:
15, Issue:
2
Journal Article
Peer reviewed
Despite longstanding recognition that small‐scale fisheries make multiple contributions to economies, societies and cultures, assessing these contributions and incorporating them into policy and ...decision‐making has suffered from a lack of a comprehensive integrating ‘lens’. This paper focuses on the concept of ‘wellbeing’ as a means to accomplish this integration, thereby unravelling and better assessing complex social and economic issues within the context of fisheries governance. We emphasize the relevance of the three key components of wellbeing – the material, relational and subjective dimensions, each of which is relevant to wellbeing at scales ranging from individual, household, community, fishery to human‐ecological systems as a whole. We review nine major approaches influential in shaping current thinking and practice on wellbeing: the economics of happiness, poverty, capabilities, gender, human rights, sustainable livelihoods, vulnerability, social capital, and social wellbeing. The concept of identity is a thread that runs through the relational and subjective components of social wellbeing, as well as several other approaches and thus emerges as a critical element of small‐scale fisheries that requires explicit recognition in governance analysis. A social wellbeing lens is applied to critically review a global body of literature discussing the social, economic and political dimensions of small‐scale fishing communities, seeking to understand the relevance and value addition of applying wellbeing concepts in small‐scale fisheries.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Marine fisheries contribute to the global economy, from the catching of fish through to the provision of support services for the fishing industry. General lack of data and uncertainty about the ...level of employment in marine fisheries can lead to underestimation of fishing effort and hence over‐exploited fisheries, or result in inaccurate projections of economic and societal costs and benefits. To address this gap, a database of marine fisheries employment for 144 coastal nations was compiled. Gaps in employment data that emerged were filled using a Monte Carlo approach to estimate the number of direct and indirect fisheries jobs. We focused on estimating jobs in the small‐scale fishing sector. We characterized small‐scale fishing as (i) primarily geared towards household consumption or sale at the local level; (ii) conducted at a low level of economic activity; (iii) minimally mechanized; (iv) conducted within inshore areas; (v) minimally managed; and/or (vi) undertaken for cultural or ceremonial purposes. In total, we estimated that 260 ± 6 million people are involved in global marine fisheries, encompassing full‐time and part‐time jobs in the direct and indirect sectors, with 22 ± 0.45 million of those being small‐scale fishers. This is equivalent to 203 ± 34 million full‐time equivalent jobs. Study results can be used to improve management decision making and highlight the need to improve monitoring and reporting of the number of people employed in marine fisheries globally.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
The study is focused to understand the micro-mechanisms that govern the deformation behavior of a Ni-rich NiTi alloy at the sub-micron scale. This alloy undergoes reversible stress induced ...martensitic transformation leading to pseudoelasticity. Correspondingly, significant strain recoverability is noted. In this investigation, nanoindentation is utilized as the primary experimental tool. Various parameters including the indenter tip configuration, size and applied load levels are varied systematically. It is observed that compared to the most commonly used sharp Berkovich indenter tip, blunt spherical tip imposes reduced amount of strain and strain-gradient within the indentation volume. This opens up the window for systematically varying the sequential deformation modes in NiTi. Further in-depth analysis revealed that optimum combination of indenter tip configuration, size and applied load level is prerequisite to appreciate the pseudoelastic mechanism in NiTi. Most importantly, a tailored and simplified protocol is formulated for converting nanoindentation load-displacement response to corresponding indentation-stress-strain behavior for pseudoelastic alloy. These indentation-stress-strain curves featuring the signature deformation characteristics of NiTi alloy are realized without utilizing any specialized experimental modes. In a nutshell, this study highlights the importance of choosing adequate nanoindentation parameters for assessing the functional characteristics of pseudoelastic NiTi system at sub-micron scale. Accordingly, overall localized deformation behavior of this unique alloy is investigated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Local support is important for the longevity of conservation initiatives. The literature suggests that perceptions of ecological effectiveness, social impacts, and good governance will influence ...levels of local support for conservation. This paper examines these relationships using data from a survey of small‐scale fishermen in 11 marine protected areas from six countries in the Mediterranean Sea. The survey queried small‐scale fishermen regarding perceptions and support for conservation. We constructed composite scores for three categories of perceptions—ecological effectiveness, social impacts, and good governance—and tested the relationship with levels of support using ordinal regression models. While all three factors were positively correlated with support for conservation, perceptions of good governance and social impacts were stronger predictors of increasing support. These findings suggest that employing good governance processes and managing social impacts may be more important than ecological effectiveness for maintaining local support for conservation.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Small‐scale robots (SSRs) have emerged as promising and versatile tools in various biomedical, sensing, decontamination, and manipulation applications, as they are uniquely capable of performing ...tasks at small length scales. With the miniaturization of robots from the macroscale to millimeter‐, micrometer‐, and nanometer‐scales, the viscous and surface forces, namely adhesive forces and surface tension have become dominant. These forces significantly impact motion efficiency. Surface engineering of robots with both hydrophilic and hydrophobic functionalization presents a brand‐new pathway to overcome motion resistance and enhance the ability to target and regulate robots for various tasks. This review focuses on the current progress and future perspectives of SSRs with hydrophilic and hydrophobic modifications (including both tethered and untethered robots). The study emphasizes the distinct advantages of SSRs, such as improved maneuverability and reduced drag forces, and outlines their potential applications. With continued innovation, rational surface engineering is expected to endow SSRs with exceptional mobility and functionality, which can broaden their applications, enhance their penetration depth, reduce surface fouling, and inhibit bacterial adhesion.
Small‐scale robots (SSRs) have emerged as promising tools in a variety of biomedical, sensing, and decontamination applications. The review encompasses the basic understanding, theory, and up‐to‐date developments related to SSRs with tailored wettabilities, ranging from hydrophilic to hydrophobic.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Small‐scale magnetic holes (SSMHs) in the magnetosphere plasma sheet are investigated in this paper. A developed electron magnetohydrodynamics (EMHD) soliton model is proposed as a new approach to ...SSMHs formation. The Biermann battery effect is taken into account in resolving the magnetic evolution equation with a slow‐mode solution in the weak nonlinear regime. Statistical investigation of SSMH observation data in the plasma sheet by Cluster is carried out in comparison with the theory. We apply multispacecraft data for distinguishing sheet‐like or cylindrical SSMHs observed and clarified by the solitary wave in the EMHD model. Furthermore, the major parameters, such as amplitude, width, maximum magnetic field perturbation, and perpendicular temperature variation of the SSMHs, are found consistent with the theoretical analysis.
Key Points
One‐dimensional and 2‐D KdV equations are derived to explain SSMHs in plasma sheet
Both sheet‐like and cylindrical SSMHs are identified in observations
The KdV soliton solutions consist with statistical observations
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Overfishing may seriously impact fish populations and ecosystems. Marine protected areas (MPAs) are key tools for biodiversity conservation and fisheries management, yet the fisheries benefits remain ...debateable. Many MPAs include a fully protected area (FPA), restricting all activities, within a partially protected area (PPA) where potentially sustainable activities are permitted. An effective tool for biodiversity conservation, FPAs, can sustain local fisheries via spillover, that is the outward export of individuals from FPAs. Spillover refers to both: “ecological spillover”: outward net emigration of juveniles, subadults and/or adults from the FPA; and “fishery spillover”: the fraction of ecological spillover that directly benefits fishery yields and revenues through fishable biomass. Yet, how common is spillover remains controversial. We present a meta‐analysis of a unique global database covering 23 FPAs worldwide, using published literature and purposely collected field data, to assess the capacity of FPAs to export biomass and whether this response was mediated by specific FPA features (e.g. size, age) or species characteristics (e.g. mobility, economic value). Results show fish biomass and abundance outside FPAs was higher: (a) in locations close to FPA borders (<200 m) than further away (>200 m); (b) for species with a high commercial value; and (c) in the presence of PPA surrounding the FPA. Spillover was slightly higher in FPAs that were larger and older and for more mobile species. Based on the broadest data set compiled to date on marine species ecological spillover beyond FPAs' borders, our work highlights elements that could guide strategies to enhance local fishery management using MPAs.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
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