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“Feeling stressed?” a critical analysis of the regulatory prescribed stress tests for financial services in the UK
Get PDFThis paper captures a qualitative review of the regulatory prescribed stress tests for UK financial services designed by the Bank of England and the Prudential Regulation Authority (PRA)/Financial Conduct Authority (FCA) after the Global Financial Crisis. It presents a critical analysis of the use of stress testing as part of supervisory practices for UK banking institutions and insurance undertakings, commenting on their qualitative characteristics, after looking at the regulatory prescribed stress tests from three key categories: the macroeconomic scenarios for banks, denoted as the bank stress tests (BST), the insurance stress tests (IST), and the biennial exploratory scenarios (BES). In this study, five trends describing regulatory prescribed stress are identified: (1) the regulatory collaboration, (2) cross-industry stress tests, (3) exploratory scenarios, (4) reporting and disclosure requirements, and (5) the underlying modelling capabilities and tools. The associated challenges of (A) governance, (B) frequency, (C) individual disclosures, (D) data and modelling, and (E) capabilities and skillset from participating institutions underpinning these stresses are highlighted, shaping the policy recommendations for future exercises. These address the gaps identified from existing stress tests towards the effective prudential supervision of UK financial services, based on each scenario category, for improvements and advances to practices
Decreasing importance of carbon-climate feedbacks in the Southern Ocean in a warming climate
Get PDFThe Southern Ocean is an important CO2 sink, mitigating climate change, but its future evolution is uncertain due to the confounding effects of stratospheric ozone recovery and climate change on ocean circulation. Using an Earth System Model, we quantify the relative influence of ozone-depleting substances and greenhouse gas emissions on this sink from 1950 to 2100. Ozone effects dominated changes in ocean circulation during 1950–2000, but not this century, implying that past trends cannot serve as proxies for future changes. Despite substantial future circulation changes induced by climate change, their effect on the CO 2 sink decreases over the 21st century because of compensating factors. Thus, the Southern Ocean is unlikely to be a major future source of amplifying carbon-climate feedbacks this century
Perceptions of fishers and Fisheries Officers of a fishing ban in Mpulungu, Lake Tanganyika, Zambia
No full textFishing bans are widely used as fisheries management tools, yet their effect on vulnerable fishing communities is poorly understood. We explored perceptions of fishers and Fisheries Officers regarding a first‐ever fishing ban on Lake Tanganyika, Zambia. Opinions were collected from 184 fishers and 16 Fisheries Officers using structured and semi‐structured questionnaires. Fishers' livelihoods and social well‐being were significantly disrupted, with 92.5% reporting income loss, 77.5% facing unemployment, and 68.8% suffering economic hardship. Hunger (37.5%), divorce (37.5%), and theft (25.0%) were also reported. In response, many fishers adopted coping strategies such as farming (45%), trading (40%), and brick‐molding (30%). Fisheries Officers identified key implementation challenges, notably illegal fishing (87.5%), resistance from fishers (81.3%), and untimely funding (68.8%), but they also noted opportunities such as promoting sustainable fishing (93.8%) and enhancing platforms for extension services (62.5%). Alternative fishing areas did not significantly influence support for the ban, whereas having alternative income sources reduced the likelihood of support for the ban. Support for the ban was significantly associated with perceived positive opportunities and education level. We conclude that fishing bans can enhance sustainability, but their success depends on providing alternative livelihoods for fishers and timely institutional support. Further research is needed on the effects of fishing bans on other stakeholders, like traders, transporters, and processors
The May 2024 event in the context of auroral activity over the past 375 yr
Get PDFWe survey 223,916 auroral records from the Northern Hemisphere observed between January 1650 and July 2024, making full allowance for the secular change in the geomagnetic field. We generate criteria for defining extreme auroral events that are met on 0.015% and 0.023% of nights since 1650 and 1790, respectively. After discussing biases and trends in the data, we compare the event of 10-11 May 2024 with other extreme events and investigate the connections to geomagnetic and sunspot activity. Ranking the events by the lowest geomagnetic latitude from which aurora was observed, the second night of the May 2024 event is shown to be the third most extensive known, the most extensive being 4 February 1872. Allowing for dark adaptation of human vision, we find no evidence that this ranking has been greatly influenced by the increased use of modern digital cameras. We show that the area of the sunspot group from where the causal CME arises (identified by the associated flare) is weakly anticorrelated with the auroral and geomagnetic response; the scatter being large such that, although the February 1872 event arose from a rather small sunspot group, the May 2024 event arose from a large group, as did the ‘Carrington Events’ of August/September 1859 (ranked 2, 4 and 5). We show that the extreme events all occur during Carrington Rotations for which the average open solar flux, FS exceeds 4 × 1014 Wb) but only 3.6% of Carrington Rotations when FS exceeds this value give an extreme event at Earth
Thermally and base-triggered ‘debond-on-demand’ crosslinked polyurethane adhesives
Get PDFTo address current industrial needs and modern legislation, a series of rapidly degradable and strongly adhering crosslinked polyurethanes featuring the commercially available and degradable chain-extender 2,2’-sulfonyldiethanol have been made for use as depolymerisable coatings and ‘debond-on-demand’ hot-melt adhesives. Variation of the chain-extended polyurethane (CEPU) composition, through increased hard segment content, provided a route to tailor the mechanical, adhesive, and degradable characteristics, whereby CEPUs with ultimate tensile strengths and elongation at break of up to 42.68 MPa and 17.59 e, respectively, could be achieved. The adhesive shear strength of the CEPUs was investigated on a selection of substrates with the highest shear strength observed of 7.80 MPa on aluminium. Depolymerization was triggered via exposure of the CEPUs to tetra-butylammonium fluoride (TBAF), causing the solubilisation of the CEPUs and the generation of low molecular weight species. Rapid ‘debond-on-demand’ adhesion was also achieved upon exposure to 1 M TBAF(aq), with losses in shear strength of up to 34% on aluminum when exposed for 30 minutes
Macromineral and trace element concentrations in conventional and organic milk and plant-based beverages in the UK: implications for population intakes
Get PDFThis study compared the minerals concentrations of milk (conventional n=20; organic n=19) to almond (conventional n=18; organic n=7) and oat (conventional n=19; organic n=13) plant-based beverages (PBB). Milk contained more Ca, Mg, P, K, I and Zn than PBB and less Na than oat PBB. Minerals concentrations of conventional and organic milk did not differ but conventional PBBs contained more Ca, P and I than organic PBBs due to permitted fortification. Despite fortification in conventional PBBs, Ca and I concentrations were lower than in milk. No differences were found between conventional and organic PBBs in concentrations of minerals that are not fortified, Mg, K and Zn. Replacement of milk with fortified conventional and organic almond and oat PBB, without other dietary changes, could reduce intakes of Ca and I below recommended intakes in some demographics, and increase prevalence of insufficiency for Mg, K, and Zn
Opportunities and challenges in combining optical sensing and epidemiological modelling
Get PDFPlant diseases impair yield and quality of crops and threaten the health of natural plant communities. Epidemiological models can predict disease and inform management. However, data are scarce, since traditional methods to measure plant diseases are resource intensive and this often limits model performance. Optical sensing offers a methodology to acquire detailed data on plant diseases across various spatial and temporal scales. Key technologies include multispectral, hyperspectral and thermal imaging, and light detection and ranging; the associated sensors can be installed on ground-based platforms, uncrewed aerial vehicles, aeroplanes and satellites. However, despite enormous potential for synergy, optical sensing and epidemiological modelling have rarely been integrated. To address this gap, we first review the state-of-the-art to develop a common language accessible to both research communities. We then explore the opportunities and challenges in combining optical sensing with epidemiological modelling. We discuss how optical sensing can inform epidemiological modelling by improving model selection and parameterisation and providing accurate maps of host plants. Epidemiological modelling can inform optical sensing by boosting measurement accuracy, improving data interpretation and optimising sensor deployment. We consider outstanding challenges in: A) identifying particular diseases; B) data availability, quality and resolution, C) linking optical sensing and epidemiological modelling, and D) emerging diseases. We conclude with recommendations to motivate and shape research and practice in both fields. Among other suggestions, we propose to standardise methods and protocols for optical sensing of plant health and develop open access databases including both optical sensing data and epidemiological models to foster cross-disciplinary work
Understanding mineral dust through a doctoral alliance
Get PDFWe present an example of how a doctoral network can bring together multidisciplinary expertise and novel scientific advances in atmospheric dust. This network (Dust-DN) has started operations and is a strategic alliance of high-profile partners, able to leverage unique facilities for atmospheric research and innovative space missions. The network aims to improve our understandings of dust processes and microphysics, identify the signature of source regions, address the socio-economic impacts of dust transport and improve the quantification of the role of dust in the climate system. The first results have already been achieved and are shown here, and many more are expected to follow
Expansionary and contractionary fiscal multipliers in the United States
No full textWe estimate the fiscal (spending) multiplier using quarterly US data, 1981Q3–2024Q4. We define government spending shocks as actual minus expected expenditure growth, the latter obtained from the Survey of Professional Forecasters. We employ the Jordà local projections method, coupled with state dependence of parameters, with smooth transition between states. A key testable hypothesis is that the positive and negative spending shocks have numerically (as well as qualitatively) different effects. We find that multipliers of shocks differ qualitatively (in terms of cyclicality) as well as quantitatively. Multipliers are almost always above unity (and often well above). Importantly, we uncover evidence that negative shocks have stronger effects over longer periods of time in the case of the FEC multipliers and likely with the PVIR‐FM multipliers, too. Pooled‐shock estimation can seriously bias results. Additionally, there is strong evidence that the two types of shock produce almost uniformly significantly different estimated coefficients of our key estimable equation
Identification of fractional-order transfer functions and nonzero initial conditions using exponentially modulated signals
Get PDFA new methodology that uses exponentially modulated signals with arbitrary excitation
waveforms for the identification of fractional order transfer functions is proposed. In contrast to
previous approaches where initial conditions were not considered and the system was required
to be at rest for the identification procedure, the current contribution extends the formulation to
the case where the system has non-zero initial conditions, dispensing with the need to place it at
a resting state. This generalization is important in feedback instrumentation and metrology
applications where the measurement or control process may not be disrupted to perform
identification. Moreover, the procedure has a broader scope of applications because it
structurally contemplates the case when the model presents derivatives in the input. Full
identification of the system parameters as well as the fractional exponents associated with the
model dynamics are achieved through a grid search procedure with resolution adjustable by the
user. Two simulation examples are presented to illustrate the effectiveness of the proposed
approach. The first example is concerned with the effect of measurement noise at the observed
system output, whereas the second involves the identification of the impedance of a
three-dimensional RC network model. These types of RC networks have dynamics capturing
complex phenomena with emergent responses and are ideal for emulating the complex
dynamics encountered across physical sciences and in particular interdisciplinary subject areas
such as biomedical engineering