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Evaluating trapped lee‐wave characteristics over the UK and Ireland in convection‐permitting model forecasts using satellite imagery
Get PDFTrapped lee waves exert frictional forces on the atmosphere which, due to the small scale of the orography that causes the waves, must be parametrised in coarser-resolution weather and climate models. Because of the scarcity of in situ observations, numerical model data have been used in previous climatological studies of trapped lee waves, which necessitates model evaluation. While the occurrence of trapped lee waves in models has been evaluated in a systematic manner before, their characteristics have not. To this end, the wavelength and orientation of trapped lee waves in the (UK) Met Office's convective-scale variable-resolution model (UKV) are validated against geostationary satellite imagery for the year 2023. The validation is performed using a newly developed wavelet transform technique for the objective estimation of wavelengths and orientations from pre-selected satellite images and corresponding model-derived vertical velocity fields. The model is shown to be skilful in reproducing trapped lee-wave wavelengths, but consistently overestimates them, especially when these wavelengths are below 9 km ( six times the model grid spacing). Anisotropy in the satellite's resolution complicates the analysis of wave orientations between the model and the satellite imagery, but they are nonetheless found to be correlated. There is no evidence for a decline in trapped lee-wave production in short-range forecasts and most of the model's skill in wavelength and orientation prediction is retained at a two-day lead time. Overall, the wavelength and orientation of trapped lee waves are generally found to be well-reproduced, which, due to the high sensitivity of trapped lee-wave characteristics to flow parameters, suggests that the UKV provides an accurate representation of the conditions relevant to trapped lee-wave formation. The model may therefore be considered a suitable substitute for observations in climatological studies of trapped lee waves and in the future development of a trapped lee-wave drag parametrisation
Low-intensity online intervention for mental distress among help-seeking young people in Hong Kong
Get PDFImportance: Mental health issues among young people are increasingly concerning. Conventional psychological interventions face challenges, including limited staffing, time commitment, and low completion rates. Objective: To evaluate the effect of a low-intensity online intervention on young people in Hong Kong experiencing moderate or greater mental distress. Design, Setting, and Participants: This randomized clinical trial was conducted from May 12, 2022, to September 22, 2023, in Hong Kong. Participants (aged 12-30 years) were recruited from a community project, self-reported moderate to severe distress (Kessler Psychological Distress Scale score ≥5), and were randomized 1:1 to receive the low-intensity online intervention or self-help tips (waitlist group). Intervention: The low-intensity online intervention group received 4 weekly 1-on-1 online sessions on stress management, sleep, or problem-solving delivered by trained psychological well-being practitioners. The waitlist group received weekly mental health tips via text messaging. Main Outcomes and Measures: Primary outcomes were changes in Kessler Psychological Distress Scale scores and depression and anxiety subscale scores of the Depression, Anxiety, and Stress Scale. Secondary outcomes included general stress, overall negative emotions, quality of life, sleep quality, resilience, and self-efficacy. The primary outcome analysis was based on intention to treat with the last observation carried forward approach. Sensitivity analyses were conducted using per-protocol and multiple imputation methods. Results: Of 332 screened participants, 120 (mean [SD] age, 22.4 [3.4] years; 87 [72.5%] female) were randomized. From baseline to 4 weeks, the low-intensity online intervention group and the control group both saw reductions in scores for depression (mean [SD] difference, 6.0 [7.7] and 4.8 [7.9]; P = .17; ηp2 = 0.02), anxiety (mean [SD] difference, 6.0 [7.7] and 3.5 [7.7]; P = .07; ηp2 = 0.03), and psychological distress (mean [SD] difference, 3.8 [3.8] and 2.9 [3.8]; P = .24; ηp2 = 0.01), but none of these differences were statistically significant. However, the intervention group showed greater reductions in general stress (mean [SD] difference, 7.5 [7.2] vs 4.4 [7.2]; P = .02; ηp2 = 0.05), negative emotion (mean [SD] difference, 20.3 [19.2] vs 12.7 [19.2]; P = .03; ηp2 = 0.04), and increased resilience (mean [SD] difference, 0.5 [0.6] vs 0.2 [0.6]; P = .01; ηp2 = 0.05) compared with the waitlist group. Younger participants and those with lower initial distress experienced greater improvements. The findings were supported by the per-protocol analysis but not by multiple imputation analysis.Conclusions and RelevanceA low-intensity online intervention did not significantly improve distress, depressive, or anxiety symptoms but showed some potential in reducing general stress and negative emotions and improving resilience. These findings are encouraging but not definitive, and caution is needed due to missing data. These data suggest that a low-intensity online intervention may offer a scalable option for youth mental health
Motivating transparent communications about bias in healthcare technology development
Get PDFAs healthcare artificial intelligence (AI) systems advance, their capacity for bias (e.g., as a function of patient protected characteristics) increases as well, and these limitations are often left undisclosed by developers. Here, the question arises - does supportive motivational messaging designed to increase buy-in inspire healthcare AI developers to transparently communicate about bias in their technology? Computer science students (Study 1: N=271; Study 2: N=209) were randomly assigned to receive a brief communication framed in either an autonomy-supportive (choice promoting) or controlling (judging and pressuring) way, emphasizing either personal benefits (gaining profit) of transparency or legal implications of non-transparency. Results showed that while communication type was not associated with behavioral intention to engage in an educational course on transparent communication about bias, both internal (self-directed) and external motivation were associated with greater intention to take a course to build transparency-congruent technology skills, as well as with greater ethical voice - intention to speak up in the service of positive transparency-consistent cultural change, and lower antagonism – i.e., a lower critical perspective regarding the need for transparency. Findings suggest that universities and workplaces should provide students and developers with a broadly supportive motivational climate, rather than a singular brief training
Seasonal contrasts in the trends of landfalling tropical cyclone track density in China (1949–2023)
Get PDFThe landfalling tropical cyclone track density (LTD) in China has shown an overall decreasing trend over the western North Pacific (WNP) while revealing an increase along the coastal East China (CEC) in the past several decades. This study further elucidates that the long-term LTD trend in the CEC exhibits a pronounced seasonal contrast that there is a significant increase from August to October, whereas a decline is observed from May to July. This seasonal reversal in the CEC LTD trend is attributed to the northward migration of an intensified diabatic heating source from May to October under global warming. This result is supported by a linear baroclinic model that incorporates realistic precipitation trends to parameterize diabatic heating over the WNP. Our finding underscores the critical role of local warming in modulating LTD trends, emphasizing its seasonal dependence rather than relying solely on sea surface temperature changes
The jazz jam session improvisation model of stakeholder engagement in entrepreneurial ecosystems
Get PDFResearch on entrepreneurial ecosystems has seen significant
growth in the last decade, with a focus on the key elements of entrepreneurial ecosystem (EE) structure, stakeholders, and interactions between them. However, the literature linking these three elements within the entrepreneurial ecosystem has yet to reach a consensus regarding how interactions between stakeholders occur within the ecosystem and beyond. We apply the jazz jam session model used by jazz musicians for improvisation to demonstrate that within a given structure of improvisation, stakeholders may improve their level and intensity of engagement, increasing the quality of the entire entrepreneurial ecosystem. The jazz jam session model explains how and why the interactions can matter and how to organize them effectively between stakeholders
Are survey stock price forecasts anchored by fundamental forecasts? A long-run perspective
Get PDFThis paper firstly shows that a wide range of asset pricing models, including full information and Bayesian rational expectations models, typically imply that agents use the long-run cointegration relationship between stock prices and fundamentals to forecast future stock prices. However, using several widely used survey forecast datasets, we provide robust new evidence that survey forecasts of aggregate stock price indices are not cointegrated with forecasts of fundamentals (aggregate consumption, dividend, and output), both at the consensus and individual level. We argue that it is crucial to relax investors’ common knowledge of the equilibrium pricing function to reconcile this finding
Surface temperature effects of recent reductions in shipping SO2 emissions are within internal variability
Get PDFIn 2020, the International Maritime Organization (IMO) implemented strict new regulations on the emissions of sulfate aerosol from the world's shipping fleet. This can be expected to lead to a reduction in aerosol-driven cooling, unmasking a portion of greenhouse gas warming. The magnitude of the effect is uncertain, however, due to the large remaining uncertainties in the climate response to aerosols. Here, we investigate this question using an 18-member ensemble of fully coupled climate simulations evenly sampling key modes of climate variability with the NCAR model, the Community Earth System Model version 2 (CESM2). We show that, while there is a clear physical response of the climate system to the IMO regulations, including a surface temperature increase, we do not find global mean temperature influence that is significantly different from zero. The 20-year average global mean warming for 2020–2040 is +0.03 °C, with a 5 %–95 % confidence range of [-0.09,0.19], reflecting the weakness of the perturbation relative to internal variability. We do, however, find a robust, non-zero regional temperature response in part of the North Atlantic. We also find that the maximum annual mean and ensemble mean warming occurs around 1 decade after the perturbation in 2029, which means that the IMO regulations have likely had very limited influence on observed global warming to date. We further discuss our results in light of other, recent publications that have reached different conclusions. Overall, while the IMO regulations may contribute up to 0.16 °C [-0.17,0.52] to the global mean surface temperature in individual years during this decade, consistent with some early studies, such a response is unlikely to have been discernible above internal variability by the end of 2023 and is in fact consistent with zero throughout the 2020–2040 period
A new look at Good Samaritans: task relevance of emotion impacts attention allocation to other people in need of help
Get PDFPaying attention to an emergency is a prerequisite for helping. However, previous evidence suggests that people often fail to notice emergencies. In contrast, the present study investigated whether inducing a background goal to notice the emotional state of others will enable attention allocation to others’ distress. To examine this assumption, we tested whether hearing emotional sounds (i.e. screams for help) increases attention towards emergency scenes while also manipulating the task relevance of the emotional value of the sounds. Specifically, participants performed a dot probe task that measured attention allocation towards emergency and matched neutral scenes. Emotional (i.e. screams for help) or neutral sounds were presented before the scenes. Participants had to encode either the valence of the sounds or the sound quality (a control condition) for a secondary task. Participants displayed an attentional bias to emergency scenes when the auditory stimulus was emotional but only when they encoded the emotional value of the sound. These results suggest that attention to emergencies is not a default but requires that paying attention to others’ suffering is relevant to the observer