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The WWRP/WCRP S2S project and its achievements
Get PDFThe World Weather Research Programme (WWRP)/World Climate Research Programme (WCRP) Subseasonal to Seasonal Prediction (S2S) project was launched in 2013 with the primary goals of improving forecast skill and understanding sources of predictability on the subseasonal timescale (from 2 weeks to a season) around the globe. Particular emphasis was placed on high-impact weather events, on developing coordination among operational centers, and on promoting the use of subseasonal forecasts by the applications communities. This 10-year project ended in December 2023. A key accomplishment was the establishment of a database of subseasonal forecasts, called the S2S database. This database enhanced collaboration between the research and operational communities, enabled studies on a wide range of topics and contributed to significant advances towards a better understanding of subseasonal predictability and windows of opportunity that contributed to improvements in forecast skill. It was used to train machine learning methods and test their performance in the S2S Artificial Intelligence/Machine Learning (AI/ML) Prize Challenge. The S2S project co-organized several coordinated research experiments to advance understanding of subseasonal predictability, and the Real-Time Pilot Initiative that provided real-time access to subseasonal data for 15 application projects. A sequence of training courses sustained over 10 years enhanced the capacity of national meteorological services in the Global South to make subseasonal forecasts. A major legacy of the S2S project was the establishment and designation of the World Meteorological organization (WMO) Global Producing Centres and Lead Centre for Sub-seasonal Predictions Multi-Model Ensemble, which will provide real-time subseasonal multi-model ensemble (MME) products to national and regional meteorological services
Specific ion effects enhance local structure in zwitterionic osmolyte solutions
Get PDFZwitterionic osmolytes are widely known to have a protein-protective effect against high salt concentration, but a mechanistic picture of osmolyte function remains elusive. Here total scattering is used to determine the room temperature liquid structure of two model cytosol solutions containing trimethylglycine (TMG) with either sodium or potassium chloride. H/D isotopic substitution is used to obtain differential neutron scattering cross sections at multiple contrasts in addition to an X-ray structure factor, and an Empirical Potential Structure Refinement (EPSR) simulation is fitted to the experimental data. We reveal the nature of the interaction between TMG molecules and ions in solution, observing binding between cations and the TMG carboxylate group. We observe three key specific ion effects: first, that sodium ions are more tightly localised at the carboxylate group; second, that sodium localisation in turn promotes head-to-head bridging between carboxylate groups when compared to potassium or no added ions, resulting in strong oxygen–oxygen correlations; and third, that sodium ions promote TMG clusters with greater orientational order, more fully shielding the ion but also in turn limiting access to the carboxylate groups for other molecules. These observations have implications for the bioavailability and protein-stabilising effect of osmolytes under changing extracellular salt conditions
A Flexible Snow Model (FSM 2.1.1) including a forest canopy
Get PDFMultiple options for representing physical processes in forest canopies are added to FSM, which is a model with multiple options for representing physical processes in snow on the ground. The canopy processes represented are shortwave and longwave radiative transfer; turbulent transfers of heat and moisture; and interception, sublimation, unloading, and melt of snow in the canopy. There are options for Beer's law or two-stream approximation canopy radiative transfer, linear or non-linear canopy snow interception efficiency, and time- and melt-dependent or temperature- and wind-dependent canopy snow unloading. Canopy mass and energy balance equations can be solved with one or two model layers. Model behaviour on stand scales is compared with observations of above- and below-canopy shortwave and longwave radiation, below-canopy wind speed, snow mass on the ground, and subjective estimates of canopy snow load. Large-scale simulations of snow cover extent, snow mass, and albedo for the Northern Hemisphere are compared with observations and land-only simulations by state-of-the-art Earth system models. Without accounting for uncertainty in forest structure metrics and parameter values, the ranges of multi-physics ensemble simulations are not as wide as seen in intercomparisons of existing models. FSM2 provides a platform for rapid investigation of sensitivity to model structure and parameter values or ensemble-based data assimilation for snow in open and forested environments
UN peacekeepers and the humanitarian community: a strained relationship
Get PDFWhat strains working relationships between United Nations (UN) peacekeepers and the humanitarian community? That is the question answered by this article. As UN peacekeeping missions and their practices evolve over time, so to do their relationships with partners and other actors in the field. The partnerships needed for a peacekeeping mission to be deployed and achieve its mandate are diverse and multifaceted. Missions such as United Nations Multidimensional Integrated Stabilization Mission in the Central African Republic (MINUSCA), United Nations Organization Stabilization Mission in the Democratic Republic of the Congo (MONUSCO), United Nations Mission in South Sudan (UNMISS) and the recently closed MINUSMA have undertaken ‘robust’ stabilisation mandates with more military capabilities than ever before which has been argued to have had a negative impact on the missions’ relationships with non-governmental organizations NGOs). This article gathers recent experiences of how UN peacekeeping missions and the humanitarian community (including other UN agencies, funds and programmes, and NGOs) work together in the field to draw out the straining factors in those relationships. To do this, 31 semi-structured interviews were undertaken between September 2023 and February 2024 with participants with experience of such relationships between peacekeepers and humanitarian actors. Whilst presenting a rich dataset of experiences of individuals working in this space, the article highlights the importance of leadership across all organisations to drive common agendas and positive working relationships that are in the interest of conflict-affected communities
Institutions, resource dependence, and the dual nature of corruption in firm internationalisation
Get PDFDespite extensive research on institutions and firm internationalisation, the joint firm and macro-level effects of informal relationships, i.e. corruption, on firm internationalisation, particularly within specific industrial contexts (resource-based versus non-resource
industries), remain underexplored. To investigate how firms internationalise under two boundary conditions—resource dependency and variations in institutional quality — we
apply the Heckman-type selection bias and use 186,027 firms spread across 137 countries, with data collected through multiple firm surveys conducted by the World Bank Enterprise
Survey (WBES) between 2006 and 2024. Our empirical findings demonstrate the double-edged sword of corruption. While it positively affects firm exports by mitigating bureaucratic
procedures at the managerial level, the effect on exports turns negative as it increases uncertainty and operational costs at the macro level. The effects are accelerated for firms in resource-based sectors. We highlight the interplay between corruption, resource dependencies, and internationalisation and provide targeted policy and practical implications
A comparative study of technology-enhanced vocabulary learning approaches: integrating self-regulated learning, examining repetition effects and role of individual differences
No full textVocabulary is essential for learning a second or foreign language, as it is closely related
to overall language proficiency. In the context of Chinese junior high schools, however,
where curriculums and teaching goals are often exam-oriented, vocabulary learning
within the language classroom faces several significant challenges. Students’ vocabulary
learning is typically driven by external motivations, relies heavily on rote learning of
wordlists, and lacks exposure to authentic contexts. Additionally, in China, limited
instructional time allocated for English learning hinders personalised support for
individual learner needs. Technology-enhanced vocabulary learning incorporating self-regulated learning (SRL) mechanism offers potential solutions to these challenges. This
current study, therefore, conducted an experiment to explore the influence of two types
of technology-enhanced vocabulary approaches, that is, digital flashcards (DF) and
video enhancement (VE), on vocabulary learning.
A mixed-method explanatory between-participant design was adopted among 132
Chinese junior high school English as a foreign language (EFL) learners from three
intact classes, randomly assigned to four experimental groups, i.e., DF, DFSRL (DF plus
SRL mechanism), VE, VESRL (VE plus SRL mechanism), and a control group. Before
the intervention, participants completed a baseline vocabulary test and a self-regulation
questionnaire to measure learners’ pre-existing levels of vocabulary knowledge and self-regulation. They also completed a vocabulary pre-test to assess their knowledge of the
sixty target words. Within a six-week intervention (one 45-minute session per week),
participants from the four experimental groups studied the target words under different
instructional conditions. In the DF group, students learned vocabulary through digital
flashcards (in the form of multiple-choice tasks with immediate feedback). In the VE
group, students studied words by watching video clips that provided real-world contexts.
The DFSRL and VESRL groups followed the same tasks as DF and VE, respectively,
but with the SRL mechanism integrated to enhance intrinsic motivation, including goal-setting, note-taking, and appraisal modules. To investigate the effects of repetitions on
vocabulary learning through the technology-enhanced approaches, the 60 target words
were divided into four lists, repeated a varying number of times: List 1 six times, List 2
five times, List 3 four times, and List 4 three times. Vocabulary learning gains were
assessed through an immediate post-test at the end of each intervention session, covering
three knowledge dimensions: written form recognition, aural form recognition, and
meaning recall. One month after the final intervention session, a vocabulary delayed
post-test evaluated the effects of different repetitions. Learners’ attitudes toward the
interventions were also gathered through open-ended questions. The control group
received no intervention but completed all vocabulary tests and the self-regulation
questionnaire.
The findings for each research question are summarised as follows. The first
research question investigated the effects of the experimental conditions. All
intervention groups achieved significantly greater learning gains than the control group
across the three dimensions of vocabulary knowledge, and VE outperformed DF in all
aspects. The SRL mechanism had varying effects: VESRL outperformed VE, and
DFSRL outperformed DF in written form recognition. For aural form recognition,
VESRL was more effective than VE, and there was no significant difference between
DFSRL and DF. For meaning recall, there was no difference between VESRL and VE,
and DFSRL was less effective than DF. The second research question examined the
moderating effects of pre-existing vocabulary knowledge and self-regulation. Self-regulation showed no significant moderating effect across the four intervention groups.
Pre-existing levels of vocabulary knowledge did not significantly moderate written or
aural form recognition but had a small negative effect on VESRL for meaning recall.
DFSRL benefited learners with higher levels of pre-existing vocabulary knowledge, and
DF was more effective for those with lower levels. The third research question explored
the role of repetitions. No significant differences in form recognition (either written or
aural) were observed across varying repetitions in VESRL, DF or DFSRL. In VE,
however, both aural and written form recognition were improved when repetitions
increased. For meaning recall, gains were significantly moderated by repetitions in all
groups with five repetitions observed as the optimum number of repetitions.
The fourth and fifth research questions examined the effects of the SRL mechanism,
focusing on the goal-setting and note-taking modules. Regarding the goal-setting
module, DFSRL learners were better at predicting their learning outcomes compared to
VESRL learners. Two key findings emerged from the note-taking module. First, most
learners in both SRL groups used repetition to reinforce the form and meaning of target
words. Second, VESRL learners focused on word form, such as part of speech, spelling,
and affixes, and DFSRL learners concentrated on word meaning, using prior knowledge
to aid recall. The final research question investigated participants’ attitudes, revealing
that VE generated greater interest and engagement than DF. Learners suggested adding
practice exercises for VE and more engaging features (e.g., pictures or music) for DF.
Finally, both groups found the note-taking module helpful for vocabulary retention, but
the goal-setting module was less effective. To sum up, the current study provides
valuable insights into theories of vocabulary learning, particularly in technology-enhanced learning contexts. The main findings highlight the effectiveness and
usefulness of technology-enhanced vocabulary learning approaches, suggesting that L2
vocabulary instruction could be more effective when combining engaging multimodal
resources, repeatedly practicing and providing personalised support
Building-neighbourhood interactions: temporal dynamics of anthropogenic and storage heat fluxes
No full textRapid urbanization and a warming climate present challenge for managing energy demand and
mitigating heat in urban environments. Buildings, as dominant elements of urban landscapes, play a
crucial role in influencing the urban energy balance through anthropogenic heat flux (QF,B) and heat
storage flux (ΔQS), thereby altering the urban thermal environment (e.g. near surface air temperature,
wind speed). These modifications, in turn, impact building thermal performance and energy use,
creating a feedback loop between buildings and the urban climate. Understanding these complex
interactions and the role of building characteristics is crucial for developing appropriate building
designs not only improve building energy efficiency but also contribute to urban climate modulation.
This thesis uses building energy modelling EnergyPlus and urban land surface model SUEWS to
quantify how building designs influence this interaction. An analytical expression of QF,B is proposed
to address its time lag and magnitude difference compared to the commonly used proxy (building
energy consumption QEC). The temporal differences at the diurnal scale are attributed to changes in
storage heat flux induced by human behaviours (ΔSo-uo), which primarily are influenced by building
operations related to thermal comfort, such as mechanical cooling and natural ventilation. The new
method for estimating QF,B is applied to further simulation work, which reveals U-value, thermal mass
levels and occupancy patterns are the most important factors to shape the diurnal patterns of QF,B,
which should be considered in urban climate modelling.
The Objective Hysteresis Model (OHM) is improved by developing a dynamic parameterization
scheme for its empirical coefficients, derived from building energy modelling data. This
parameterization allows the OHM coefficients to respond to variations in building construction
properties and meteorological conditions, thereby reducing biases of ΔQS compared to using fixed
coefficients derived from long-term observations.
Furthermore, a two-way coupling between the SUEWS and EnergyPlus is introduced, capturing
feedback mechanisms between retrofitted buildings and neighbourhood climate across different U.S.
climate zones. The results show a pronounced winter nighttime overcooling effect and secondary
feedback on heating energy demand due to reduced outdoor temperature. This impact of energy
retrofitting is more pronounced in low-wind cities, where high aerodynamic resistance amplifies the
temperature feedback resulting from changes in QF,B.
Overall, this thesis extends the current understanding of how building factors influence the interaction
between building and urban environment through QF,B and ΔQS. The methods and insights developed
here can guide policymakers and building/urban planners in formulating strategies for sustainable
urban development and enhancing climate resilience
The caatinga dry tropical forest: a highly efficient carbon sink in South America
No full textSeasonally Dry Tropical Forests (SDTFs) may act as considerable carbon sinks, regulating the atmospheric and terrestrial carbon storage and fluxes with implications for local, regional and global climates. In the Caatinga, an endemic Brazilian SDTF, the research on the magnitude of the CO2 sink is still incipient. To address this gap, we conducted a comprehensive analysis of observed CO2 fluxes using the Eddy Covariance technique across the Caatinga, quantifying and assessing the seasonal and interannual variations in CO2 exchange under contrasting soil and climatic conditions. In our study we estimated whether the Caatinga functioned as a net source or sink of carbon at five sites during years with varying rates of rainfall. Results showed that the dynamics of CO2 flux components varied based on the spatio-temporal distribution and magnitude of rainfall and the corresponding variations in vegetation cover. Average annual accumulated Gross Primary Productivity ranged from 1,167 g C m-2 in the Crystalline area to 2,018 g C m-2 in the Agreste ecotone. Average annual Net Ecosystem Exchange was -775 g C m-2 (-7.7 t C ha-1). The Caatinga exhibited higher carbon use efficiency (CUE) compared to other dry forests in arid and semi-arid regions worldwide and to South American ecosystems, including the Amazon, as documented by FLUXNET2015 eddy covariance datasets. CUE values ranged from 0.31 in the Crystalline area to 0.58 in the Agreste ecotone. These findings provide robust, measurement-based evidence that the Caatinga is a highly efficient carbon sink, substantially contributing to atmospheric CO2 absorption and mitigating the growth rate of atmospheric CO2 concentration