Found 9989 publications. Showing page 17 of 400:
2024
Understanding thermal comfort expectations in older adults: The role of long-term thermal history
Understanding how long-term thermal history affects thermal comfort expectations in older adults (65+) has implications for designing energy-efficient spaces in a changing climate. A growing number of studies focus on thermal sensation/preference votes to represent the current thermal comfort expectations, often overlooking their limitations. This study, however, investigates how factors shaping long-term thermal history link to the current 65+ adults indoor thermal comfort expectations during exposure to heat, by focusing on the upper limit of thermally acceptable temperature range, represented by a self-reported temperature threshold at which 65+ adults believe to feel uncomfortable by indoor heat (Tit). To find Tit, we use answers to “Above what temperature do you start feeling too hot indoors?” by survey respondents in Warsaw (n = 678) and Madrid (n = 527), who lived in their apartment ≥5 years. Statistically, we find indoor factors affecting long-term thermal experiences more significant in explaining 65+ Tit, when compared to outdoor factors such as distance to water, vegetation, or surface thermal radiance. Better-insulated buildings were associated with a lower Tit [...]
2024
2024
2024
To achieve the objectives of COP28 for transitioning away from fossil fuels and phasing these out, both natural and technological solutions are essential, necessitating a step-change in how we implement social innovation. Given the significant CO2 emissions produced by the building sector, there is an urgent need for a transformative shift towards a net-zero building stock by mid-century. This transition to zero-energy and zero-emission buildings is difficult due to complex processes and substantial costs. Building integrated photovoltaics (BIPV) offers a promising solution due to the benefits of enhanced energy efficiency and electricity production. The availability of roof and façade space in offices and other types of buildings, especially in large cities, permits photovoltaic integration in both opaque and transparent surfaces. This study investigates the synergistic relationship between solar conversion technologies and nature-based components. Through a meta-analysis of peer-reviewed literature and critical assessment, effective BIPVs with greenery (BIPVGREEN) combinations suitable for various climatic zones are identified. The results highlight the multi-faceted benefits of this integration across a range of techno-economic and social criteria and underscore the feasibility of up-scaling these solutions for broader deployment. Applying a SWOT analysis approach, the internal strengths and weaknesses, as well as the external opportunities and threats for BIPVGREEN deployment, are investigated. The analysis reveals key drivers of synergistic effects and multi-benefits, while also addressing the challenges associated with optimizing performance and reducing investment costs. The strengths of BIPVGREEN in terms of energy efficiency and sustainable decarbonization, along with its potential to mitigate urban and climate temperature increases, enhance its relevance to the built environment, especially for informal settlements. The significance of prioritizing this BIPVGREEN climate mitigation action in low-income vulnerable regions and informal settlements is crucial through the minimum tax financing worldwide and citizen's engagement in architectural BIPVGREEN co-integration.
2024
2024
2024
A reliable determination of equivalent black carbon (eBC) mass concentrations derived from filter absorption photometers (FAPs) measurements depends on the appropriate quantification of the mass absorption cross-section (MAC) for converting the absorption coefficient (babs) to eBC. This study investigates the spatial–temporal variability of the MAC obtained from simultaneous elemental carbon (EC) and babs measurements performed at 22 sites. We compared different methodologies for retrieving eBC integrating different options for calculating MAC including: locally derived, median value calculated from 22 sites, and site-specific rolling MAC. The eBC concentrations that underwent correction using these methods were identified as LeBC (local MAC), MeBC (median MAC), and ReBC (Rolling MAC) respectively. Pronounced differences (up to more than 50 %) were observed between eBC as directly provided by FAPs (NeBC; Nominal instrumental MAC) and ReBC due to the differences observed between the experimental and nominal MAC values. The median MAC was 7.8 ± 3.4 m2 g-1 from 12 aethalometers at 880 nm, and 10.6 ± 4.7 m2 g-1 from 10 MAAPs at 637 nm. The experimental MAC showed significant site and seasonal dependencies, with heterogeneous patterns between summer and winter in different regions. In addition, long-term trend analysis revealed statistically significant (s.s.) decreasing trends in EC. Interestingly, we showed that the corresponding corrected eBC trends are not independent of the way eBC is calculated due to the variability of MAC. NeBC and EC decreasing trends were consistent at sites with no significant trend in experimental MAC. Conversely, where MAC showed s.s. trend, the NeBC and EC trends were not consistent while ReBC concentration followed the same pattern as EC. These results underscore the importance of accounting for MAC variations when deriving eBC measurements from FAPs and emphasize the necessity of incorporating EC observations to constrain the uncertainty associated with eBC.
2024
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2024
We determine the global emission distribution of the potent greenhouse gas sulfur hexafluoride (SF6) for the period 2005–2021 using inverse modelling. The inversion is based on 50 d backward simulations with the Lagrangian particle dispersion model (LPDM) FLEXPART and on a comprehensive observation data set of SF6 mole fractions in which we combine continuous with flask measurements sampled at fixed surface locations and observations from aircraft and ship campaigns. We use a global-distribution-based (GDB) approach to determine baseline mole fractions directly from global SF6 mole fraction fields at the termination points of the backward trajectories. We compute these fields by performing an atmospheric SF6 re-analysis, assimilating global SF6 observations into modelled global three-dimensional mole fraction fields. Our inversion results are in excellent agreement with several regional inversion studies in the USA, Europe, and China. We find that (1) annual US SF6 emissions strongly decreased from 1.25 Gg in 2005 to 0.48 Gg in 2021; however, they were on average twice as high as the reported emissions to the United Nations. (2) SF6 emissions from EU countries show an average decreasing trend of −0.006 Gg yr−1 during the period 2005 to 2021, including a substantial drop in 2018. This drop is likely a direct result of the EU's F-gas regulation 517/2014, which bans the use of SF6 for recycling magnesium die-casting alloys as of 2018 and requires leak detection systems for electrical switch gear. (3) Chinese annual emissions grew from 1.28 Gg in 2005 to 5.16 Gg in 2021, with a trend of 0.21 Gg yr−1, which is even higher than the average global total emission trend of 0.20 Gg yr−1. (4) National reports for the USA, Europe, and China all underestimated their SF6 emissions. (5) Our results indicate increasing emissions in poorly monitored areas (e.g. India, Africa, and South America); however, these results are uncertain due to weak observational constraints, highlighting the need for enhanced monitoring in these areas. (6) Global total SF6 emissions are comparable to estimates in previous studies but are sensitive to a priori estimates due to the low network sensitivity in poorly monitored regions. (7) Monthly inversions indicate that SF6 emissions in the Northern Hemisphere were on average higher in summer than in winter throughout the study period.
2024
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2024
NILU og Transportøkonomisk institutt (TØI) har på oppdrag fra Miljødirektoratet videreutviklet modellen NERVE («Norwegian Emissions from Road Vehicle Exhaust») for beregning av klimagassutslipp fra veitrafikken i norske kommuner. NERVE-modellen anvender de mest detaljerte datasettene for bilpark, utslippsfaktorer, trafikk og veier for spesifikke lokale forhold. Datasettene er kombinert i en datastruktur som gjør at resultat kan aggregeres på et lite eller et stort geografisk område. NERVE kan således betegnes som en «bottom-up»-utslippsmodell, fordi den er bygget opp «nedenfra» fra detaljerte datakilder. Denne rapporten presenterer metodikken og antagelsene bak beregningene med NERVE, og sammenligner resultat aggregert på nasjonalt nivå med annen tilgjengelig nasjonal statistikk.
NILU
2024
Query-driven Qualitative Constraint Acquisition
Many planning, scheduling or multi-dimensional packing problems involve the design of subtle logical combinations of temporal or spatial constraints. Recently, we introduced GEQCA-I, which stands for Generic Qualitative Constraint Acquisition, as a new active constraint acquisition method for learning qualitative constraints using qualitative queries. In this paper, we revise and extend GEQCA-I to GEQCA-II with a new type of query, universal query, for qualitative constraint acquisition, with a deeper query-driven acquisition algorithm. Our extended experimental evaluation shows the efficiency and usefulness of the concept of universal query in learning randomly-generated qualitative networks, including both temporal networks based on Allen’s algebra and spatial networks based on region connection calculus. We also show the effectiveness of GEQCA-II in learning the qualitative part of real scheduling problems.
2024
Investigating snow deposition of cyclic siloxanes in an Arctic environment
cVMS are high production volume chemicals that are used for a wide range of industrial and domestic applications. Given the high volatility of cVMS, emissions occur mainly to the atmosphere, and cVMS are present in the Arctic atmosphere, e.g. at the Zeppelin Observatory near Ny Ålesund, Svalbard, suggesting potential for long-range atmospheric transport. A study to investigate whether cVMS have the potential to deposit to surface media, and thereby represent a potential risk to the terrestrial or marine environment in polar and Arctic regions was carried out. Overall, cVMS levels in samples of vegetation, soil, sediment and marine biota were low. D4 was detected in most samples at concentrations above LOD, but below LOQ, while D5 and D6 were generally not detected. The low cVMS concentrations in soil, vegetation, sediments, and fish are in line with most current research on cVMS in remote regions, which together suggest that input of cVMS from atmospheric deposition and snow melt is likely not a major contributing source.
NILU
2024