Fant 10035 publikasjoner. Viser side 384 av 402:
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
2003
2007
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2004
2003
Undersøkelse av svevestøv ved veier. Elevbasert forskningskampanje som del av Forskningsdagene 2004. NILU OR
2005
2018
Anthropogenic activities emit ~2,000 Mg y−1 of the toxic pollutant mercury (Hg) into the atmosphere, leading to long-range transport and deposition to remote ecosystems. Global anthropogenic emission inventories report increases in Northern Hemispheric (NH) Hg emissions during the last three decades, in contradiction with the observed decline in atmospheric Hg concentrations at NH measurement stations. Many factors can obscure the link between anthropogenic emissions and atmospheric Hg concentrations, including trends in the reemissions of previously released anthropogenic (“legacy”) Hg, atmospheric sink variability, and spatial heterogeneity of monitoring data. Here, we assess the observed trends in gaseous elemental mercury (Hg0) in the NH and apply biogeochemical box modeling and chemical transport modeling to understand the trend drivers. Using linear mixed effects modeling of observational data from 51 stations, we find negative Hg0 trends in most NH regions, with an overall trend for 2005 to 2020 of −0.011 ± 0.006 ng m−3 y−1 (±2 SD). In contrast to existing emission inventories, our modeling analysis suggests that annual NH anthropogenic emissions must have declined by at least 140 Mg between the years 2005 and 2020 to be consistent with observed trends. Faster declines in 95th percentile Hg0 values than median values in Europe, North America, and East Asian measurement stations corroborate that the likely cause is a decline in nearby anthropogenic emissions rather than background legacy reemissions. Our results are relevant for evaluating the effectiveness of the Minamata Convention on Mercury, demonstrating that existing emission inventories are incompatible with the observed Hg0 declines.
2024
Unexpected nascent atmospheric emissions of three ozone-depleting hydrochlorofluorocarbons
Global and regional atmospheric measurements and modeling can play key roles in discovering and quantifying unexpected nascent emissions of environmentally important substances. We focus here on three hydrochlorofluorocarbons (HCFCs) that are restricted by the Montreal Protocol because of their roles in stratospheric ozone depletion. Based on measurements of archived air samples and on in situ measurements at stations of the Advanced Global Atmospheric Gases Experiment (AGAGE) network, we report global abundances, trends, and regional enhancements for HCFC-132b (CH2ClCClF2), which is newly discovered in the atmosphere, and updated results for HCFC-133a (CH2ClCF3) and HCFC-31 (CH2ClF). No purposeful end-use is known for any of these compounds. We find that HCFC-132b appeared in the atmosphere 20 y ago and that its global emissions increased to 1.1 Gg⋅y−1 by 2019. Regional top-down emission estimates for East Asia, based on high-frequency measurements for 2016–2019, account for ∼95% of the global HCFC-132b emissions and for ∼80% of the global HCFC-133a emissions of 2.3 Gg⋅y−1 during this period. Global emissions of HCFC-31 for the same period are 0.71 Gg⋅y−1. Small European emissions of HCFC-132b and HCFC-133a, found in southeastern France, ceased in early 2017 when a fluorocarbon production facility in that area closed. Although unreported emissive end-uses cannot be ruled out, all three compounds are most likely emitted as intermediate by-products in chemical production pathways. Identification of harmful emissions to the atmosphere at an early stage can guide the effective development of global and regional environmental policy.
2021
Unleaded gasoline as a significant source of Pb emissions in the Subarctic
After the phasing out of leaded gasoline, Pb emissions to the atmosphere dramatically decreased, and other sources became more significant. The contribution of unleaded gasoline has not been sufficiently recognized; therefore, we evaluated the impact of Pb from unleaded gasoline in a relatively pristine area in Subarctic NE Norway. The influence of different endmembers (Ni slag and concentrate from the Nikel smelter in Russia, PM10 filters, and traffic) on the overall Pb emissions was determined using various environmental samples (snow, lichens, and topsoils) and Pb isotope tracing. We found a strong relationship between Pb in snow and the Ni smelter. However, lichen samples and most of the topsoils were contaminated by Pb originating from the current use of unleaded gasoline originating from Russia. Historical leaded and recent unleaded gasoline are fully distinguishable using Pb isotopes, as unleaded gasoline is characterized by a low radiogenic composition (206Pb/207Pb = 1.098 and 208Pb/206Pb = 2.060) and remains an unneglectable source of Pb in the region.
2018
2017
Unprecedented shifts in aerosol pollution sources in China under a decade of clean air actions
China is a major hotspot of black carbon (BC) emissions, contributing to climate warming and risk to public health. Here, our dual-isotope-constrained observations indicate stringent air pollution controls have drastically reduced coal-burning in North China over the past decade, marking a transition to a “post-coal” era compared to earlier 2012–2014. However, biomass-burning fraction (fbb) for north/central/east winter hazes has doubled from earlier (north/east) ~20%, with significantly higher fbb during polluted winters. Comparisons between observation and transport modelling show good alignment in BC concentrations but substantial discrepancies in source attribution (i.e., fbb). Leveraging radiocarbon measurements, advanced atmospheric modelling, and a Bayesian approach, our study identifies biases stemming from misallocated residential fuel types in emission inventories. These findings underscore the untapped potential to mitigate BC emissions by targeting rural biomass burning, while providing critical insights into BC source evolution to refine emission inventories and formulate effective air quality policies for China and other nations facing severe air pollution.
2025
2023
Inert spredning av et enhetsutslipp er kombinert med tidsavhengig luftkjemi for å beregne maksimal belastning I luft og ferskvann for utslipp fra aminabsorberen ved TCM. Beregningene for et likely case viser at maksimal belastning av summen av nitrosaminer og nitraminer er 2 % av anbefalt retningslinje for luftkvalitet. Maksimale konsentrasjoner i ferskvann fra utslippet er fra 0.6 % til 3.2 % av retningslinjen avhengig av hvilken absorbent som benyttes og hvilken avgass som renses. For likely case i forhold til worst case er luftkonsentrasjonene en faktor 3 til 4 lavere enn worst case. Ferskvannkonsentrasjonene blir en faktor fra 16 til 22 lavere enn worst case avhengig av hvilken absorbent som benyttes.
2011
Inert spredning av et enhetsutslipp er kombinert med tidsavhengig luftkjemi for å beregne maksimal belastning I luft og ferskvann for utslipp fra aminabsorberen ved TCM. Beregningene for et worst case viser at maksimal belastning av summen av nitrosaminer og nitraminer er 5 % av anbefalt retningslinje for luftkvalitet. Maksimale konsentrasjoner i ferskvann fra utslippet er fra 13 % til 53 % av retningslinjen avhengig av hvilken absorbent som benyttes og hvilken avgass som renses. Effekten av et "likely case" er estimert. Estimatet viser at luftkonsentrasjonene blir en faktor 3 lavere enn worst case. Ferskvannkonsentrasjonene blir en faktor fra 10 til 20 lavere enn worst case avhengig av hvilken absorbent som benyttes.
2011
Update of background concentrations over Norway. NILU OR
A methodology for creating a new dataset of estimated background concentrations of NO2, O3, PM10, and PM2.5 that are representative of a typical year over Norway, was developed. The dataset has a spatial resolution of 10 km × 10 km and an hourly temporal resolution. The methodology is based on a spatial mapping component for obtaining information on annual mean background concentrations, and a temporal characterization component, which uses long-term time series of station data to describe the typical development of background concentrations throughout a day and a year. When combined, these two components allow estimates of typical background concentrations at any time of the year at any location in Norway. Whereas the previously used VLUFT method of 1993 only provided spatially constant data at the county level, the new method presented here provides spatially continuous data at a comparatively high spatial resolution. Furthermore, while the previous method only gave a range of constant values that were considered valid throughout the entire year, the new technique provides continuous time series for a typical year at hourly resolution at any location in Norway.
2011