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Outrunning flash floods: improving global medium-range forecasts for better preparedness
Full text linkThe UN’s ”Early Warning for All” initiative, supported by WMO, prioritises flash floods due
to their high mortality rates, widespread exposure, major economic impacts, and climate
driven exacerbation. Global medium-range predictions are essential for protecting vulnerable
populations. However, despite recent advances in medium-range numerical weather prediction
and hydrological modelling, developing medium-range predictions of areas at risk of flash floods
over a continuous global domain remains severely constrained by computational requirements,
data availability, and the inherent challenge of predicting localised extreme events.
This thesis aims to develop a first proof-of-concept of medium-range (up to day 5) predictions of areas at risk of flash floods over a continuous global domain. To achieve this goal,
three interconnected research objectives are addressed using the Continental United States
(CONUS) as the primary study region. The selection of CONUS leverages the Storm Event
Database, which provides a comprehensive long-term record of flash flood impact reports
essential for robust model development and validation.
First, a flash-flood-focused verification framework, directly comparing rainfall predictions
and flash flood impact reports, is developed. This framework is used throughout the thesis, but
it is first used to assess whether rainfall forecasts from global NWP models can identify areas at
risk of flash floods up to medium-range lead times. The ERA5 reanalysis and ERA5 forecasts,
post-processed with the ecPoint technique, show good reliability and discrimination ability up
to day 5.
Second, multiple data-driven models—including random forest, gradient boosting, and
neural networks—are evaluated to determine their capacity to extract predictive signals using
severely imbalanced observational datasets. These models integrate hydro-meteorological
variables from the ERA5 reanalysis and forecasts with flash flood impact reports to identify
patterns indicative of flash flood risk. When compared to rainfall-based predictions alone, the
data-driven hydro-meteorological predictions demonstrate superior performance while maintaining computational efficiency suitable for operational deployment. Among the tested models,
the XGBoost implementation of gradient boosting emerges as the best performer.
Third, systematic sensitivity analysis demonstrates that it is possible to deploy such a
regionally-trained data-driven model with global hydro-meteorological forecasts to produce
medium-range predictions of areas at risk of flash floods over a continuous global domain.
This research helps to establish methodologies to extract valuable predictive information
from limited observational datasets and lower-resolution hydro-meteorological forecasts that
could enhance preparedness and emergency management strategies, contributing to the UN’s
”Early Warnings for All” initiative
The influence of ambivalence, habits, perceived privacy, and trust on consumer data disclosure in online booking: a cross-cultural study
No full textThe growing use of digital marketing has heightened concerns about privacy, particularly regarding the disclosure of personal data during online transactions. In online shopping, consumers are often required to provide personal information to access services offered by
digital companies. At the same time, they worry that their data may be used by third parties for unrelated purposes without their consent. This behaviour reflects the so‑called privacy paradox, in which consumers express strong privacy concerns yet continue to share personal data in exchange for perceived benefits. This study, therefore, examines how consumers’ willingness to disclose (WTD) sensitive personal information when using online travel agencies (OTAs) is influenced by sociodemographic and psychological factors associated with the privacy paradox.
To address this objective, both qualitative and quantitative data were used. Qualitative data were gathered through in‑depth interviews and focus groups. Participants for the interviews were recruited using a snowball sampling technique, while focus group participants were selected through an open recruitment process. Insights from these qualitative activities revealed that online booking decisions are shaped by several factors, including consumer
ambivalence, trust, demographic characteristics, and concerns about the lack of transparency in personal data usage. Qualitative data were analysed using NVivo software. Findings from the qualitative phase informed the development of a contingent valuation survey administered in Indonesia and the UK to 493 and 489 participants, respectively. The survey included questions designed to assess how respondents’ sociodemographic
characteristics, habits, online privacy literacy, concerns, and psychological factors—such as trust, perceived risks and benefits, and ambivalence—influence their willingness to disclose sensitive data when booking travel online. For respondents willing to disclose personal information, a contingent valuation scenario was used to estimate the price at which they were willing to pay (WTP) or willing to accept (WTA) compensation for releasing health‑related information. WTP and WTA values were elicited using the payment card and double‑bounded dichotomous choice techniques, respectively. WTD was estimated using 28
logistic regression, while WTP and WTA were analysed using Tobit and interval regression models. Results indicate that age and benefit–risk assessment positively influence WTD, whereas privacy concerns negatively affect it. Habits, expenditure, and booking frequency positively influence WTP. Education level and trust increase WTA, while age and technical familiarity reduce WTA. Cross‑cultural comparisons show that UK consumers exhibit stronger privacy concerns and higher WTP to protect personal data, whereas Indonesian consumers are more likely to accept discounts in exchange for data sharing, influenced by contextual trust and economic considerations. Overall, the findings highlight the importance of transparent data practices, enhanced consumer education, and trust‑building initiatives in e‑commerce. This study contributes to a deeper understanding of consumer privacy concerns and decision‑making in the digital
economy, emphasising the complexities underlying online behaviour. Implications for marketers, policymakers, and online businesses are discussed, with a focus on
strengthening privacy protection and fostering consumer trust to support sustainable e‑commerce growth. Future research should examine longitudinal behavioural patterns and the impact of emerging technologies on data‑sharing preferences across cultures
A framework for research-informed typeface design: starting with Greek
No full textThis chapter summarizes the context within which Greek typeface development happens, and identifies externally imposed limitations and biases that have affected the forms of letters in current digital typefaces. In response, it proposes a methodology that focuses on primary sources, and looks at sociotechnical factors to capture formal fundamentals of the script, and inform future development. To demonstrate this method the chapter includes the results of analyses of capital letters, lowercase letters, and diacritics. It concludes with indications of further areas this approach is applicable for Greek typography, and suggests that the methodology is a useful framework for other scripts
A global analysis of pollen-based reconstructions of land climate changes during Dansgaard–Oeschger events
Full text linkDansgaard–Oeschger (D–O) warming events are comparable in magnitude and rate to the anticipated 21st century warming. As such, they provide a good target for evaluation of the ability of state-of-the-art climate models to simulate rapid climate changes. Despite the wealth of qualitative information about climate changes during the D–O events, there has been no attempt to date to make quantitative reconstructions globally. Here we use frequency-corrected Tolerance-weighted Weighted Averaging Partial Least Squares regression (fxTWA-PLS) to reconstruct mean temperature of the coldest month, mean temperature of the warmest month, and a plant-available moisture index across multiple D–O events between 50 and 30 ka based on available pollen records across the globe. The reconstruction of plant-available moisture is corrected for the impact of changing atmospheric CO2 concentrations on plant water use efficiency. These reconstructions show that the largest warming occurred in northern extratropics, especially Eurasia, while western North America and the southern extratropics were characterised by cooling. The change in winter temperature was significantly larger than the change in summer temperature in the northern extratropics and the tropics, indicating that the D–O warming events were characterised by reduced seasonality, but there was no significant difference between the summer and winter temperature changes in the southern extratropics. The antiphasing between northern and southern extratropical changes, and the west-east pattern of cooling and warming in North America were generally consistent across the eight D–O events examined, although coherency is greatest during the strongest events. There was no globally consistent pattern between changes in moisture and changes in temperature. These reconstructions can be used to evaluate the spatial patterns of changes in temperature and moisture in the transient simulations of the D–O events planned as part of the Palaeoclimate Modelling Intercomparison Project
Dimension-specific party and public opinion responsiveness in the EU immigration acquis
Full text linkHow are national party positions and national public opinion balanced when voting on the multi-dimensional immigration policies of the EU, which encompass both immigration and EU integration dimensions? The study applies the Wordscores algorithm on 1990–2018 EU immigration policies’ texts and examines the voting behaviour of national parties in the European Parliament (EP). It incorporates roll-call votes, CHES, and Eurobarometer data covering over 350 parties to test the influence of (a) parties’ programmatic positions; (b) national public opinion on parties’ level of support for EU immigration dossiers’ contents. The study provides the first comprehensive evidence that the EU immigration acquis has become increasingly restrictive and that restrictive and liberal provisions frequently co‑occur with, respectively, pro‑EU integration and pro‑sovereignty provisions. Parties adhere more closely to party positions on the immigration dimension but are more responsive to short-term changes in public opinion on the EU integration dimension instead
Connecting the Atlantic Meridional Overturning Circulation to the Southern Ocean following the closure of equatorial seaways during the Cenozoic
Full text linkGlobal ocean circulation regulates climate and has undergone significant changes over the Cenozoic. Today, the Atlantic Meridional Overturning Circulation (AMOC) is driven by North Atlantic Deep Water (NADW) formation and Southern Ocean upwelling. By contrast, during the middle Eocene to early Oligocene (48–28 Ma), a restricted Drake Passage was limiting the northern Ekman transport, while a circum-equatorial current sustained by trade winds promoted low-latitude upwelling. Our set of simulations with the IPSL-CM5A2 model reveals that this paleogeographic setting favored proto-NADW upwelling at low latitudes, confining the AMOC to the Northern Hemisphere. Consequently, the role of southern westerly winds was limited, and the northward heat transport was weaker than in the modern ocean
The performance effects of "added cultural distance" in multinational expansion paths: generalizable and contextual determinants
No full textPurpose: Hutzschenreuter and Voll (2008) introduced the “added distance” concept in international business strategy. They showed the negative impact on German multinational enterprise (MNE) performance of multiple investment steps with a high added distance in aggregate. This paper aims to explore the generalizability of this finding using a Penrosean perspective and quasi-replicating their methodology.
Design/methodology/approach: Empirically, the authors focus on the context of Indian firms, posteconomic liberalization (1991), where a much wider spectrum of magnitudes of added distance could be observed than in the German case. The authors use data of 109 Indian firms with expansion paths the authors tracked during periods ranging from 6 to 31 years.
Findings: The authors show that moderate added distance enhances performance in the subsequent period, but only up to a threshold. The underlying reason for this outcome is a meta-bounded-rationality challenge: senior managers underestimate how the aggregate of multiple international investment steps with added cultural distance, each supposedly beneficial to the firm, leads to unmet demands for managerial capacity and reduces corporate coherence.
Research limitations/implications: The major research implication of the work is that studies in international business should not make use of dyadic, macrolevel distances in studies on implications of internationalization on performance.
Practical implications: The findings highlight that MNEs must match international expansion opportunities with adequate managerial resources. For senior executives, careful planning of internationalization steps and attention to the cumulative distance added in each period is crucial to avoid negative performance effects of over-expansion.
Originality/value: To the best of the authors’ knowledge, this is the first empirical study that shows in a comprehensive way, over a long period of time, the impact of “added distance” on the relationship between internationalization in one period and performance in the period immediately following.It demonstrates the vulnerabilities of MNEs when expanding abroad in a too ambitious fashion and extends Penrosean thinking is this realm
Climate warming at European airports: human factors and infrastructure planning
Full text linkTemperature and related thermal comfort metrics at a representative 9-member ensemble of airports in Europe are presented using a combination of historical (1985–2014) and future projection (2035–2064) timescales under a variety of forcing scenarios. Data are shown for summer (June–July–August) and the nine sites are further grouped into ‘oceanic’, ‘continentally influenced’, and ‘Mediterranean coastal’ climate types, which ameliorates visualisation and provides more generalised policy-relevant results. Using the Humidex metric, it is shown that some airports in southern Europe may enter a ‘dangerous’ (>45 °C) regime of human discomfort. This would be accompanied by economic impacts related to longer mandated rest periods for ground workers, as well as increased water intake and changes to health and safety training. The coincidence of the 38 °C flash point of kerosene jet fuel with perturbed daily maximum temperature occurrence thresholds at some sites will likely also have knock-on effects on safety practices since some sites may experience 70% of future summer days with temperatures exceeding this value. Using an 18 °C threshold for defining cooling and heating ‘degree days’, increases in cooling requirements are projected to be larger than reductions in heating for continental and Mediterranean sites, and heatwave occurrence (3 or more days at or above the 95th historical percentile) may increase by a factor of 10. From a building and infrastructure services perspective, increased temperature variability around larger average values has the potential to reduce safe runway lifetimes and increase structural fatigue in large-span steel terminal buildings