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As the vegetation in the Arctic changes, tundra ecosystems along the southern border of the Arctic are becoming greener and gradually giving way to boreal ecosystems. This change is affecting local populations, wildlife, energy exchange processes between environmental compartments, and the carbon cycle. To understand the progression and the implications of this change in vegetation, satellite measurements and surface models can be employed. However, in situ observational data are required to validate these measurements and models. This paper presents observational data from two nearby sites in the forest–tundra ecotone in the Tasiapik Valley near Umiujaq in Northern Quebec, Canada. One site is on a mixture of lichen and shrub tundra. The associated data set comprises 9 years of meteorological, soil and snow data as well as 3 years of eddy covariance data. The other site, 850 m away, features vegetation consisting mostly of tall shrubs and black spruce. For that location, 6 years of meteorological, soil and snow data are available. In addition to the data from the automated stations, profiles of snow density and specific surface area were collected during field campaigns. The data are available at 10.1594/PANGAEA.964743 (Domine et al., 2024). [ABSTRACT FROM AUTHOR]

Several studies have shown the benefits of using timber in the construction sector in terms of climate change, which has received the support of decision-makers. However, few studies focus on other environmental indicators. The environmental impacts (i.e., such as human health, ecosystem quality, and resources) of material substitutions, consequence of the increasing use of wood, are still lacking in the literature. Studies that compare different structural materials focus either on a single building or on one structural system that would be representative on a larger scale. However, the environmental benefits of some projects are not easily extrapolated to the scale of a given region with a variety of architectures. Higher-order effects, beyond the building scale, can indeed imply changes in the resource availability according to the unconstrained suppliers and resources. The objective of this paper is to assess the life cycle environmental consequences of wood substitutions at a regional scale for the non-residential construction sector. The increasing use of wood structures for non-residential buildings in the province of Quebec (Canada) is used as a case study. The method includes the development of material substitution factors by comparing several structures. The substitution factors show that, on average, wood can replace, simultaneously, 0.59 and 4.54 times the weight of steel and concrete, respectively. However, steel substitution has more advantages than concrete substitution. Among the tested parameters, the variability of the material substitution factors implies more uncertainties in the results. The originality of our study lies in the limitations that may change the conclusions drawn from the substitution at a large scale. With three substitution scenarios for four impact categories, the results showed an advantage of using wood in seven of the twelve combinations. The ecosystem quality indicator is the most unfavorable and shows opposite trends to climate change, human health, and resource indicators. Considering average material substitution factors combined with the maximum potential use of wood in non-residential (NR) structures in Quebec in 2050, wood can contribute to avoid 2.6 Mt of carbon dioxide equivalent (CO 2 eq.). This amount is equivalent to 3.5% of Quebec's CO 2 eq. emission reduction target by 2050 compared to 1990. • The environmental consequences of wood substitution at the regional level for the non-residential sector are assessed. • The average scenario suggests that the use of wood can avoid up to 2.62 Mt of CO 2 eq. in 2050. • The variability of material substitution factors implies the greatest variability in the results. • With three substitution scenarios for four impact categories, the results showed an advantage for wood increased use in seven of the twelve combinations. [ABSTRACT FROM AUTHOR]

Accurate visualization of air temperature distribution can be useful for various thermal analyses in fields such as human health and heat transfer of local area. This paper presents a novel approach to measuring air temperature from midwave hyperspectral Fourier transform infrared (FTIR) imaging in the carbon dioxide absorption band (between 4.25–4.35 μ m). In this study, the proposed visual air temperature (VisualAT) measurement is based on the observation that the carbon dioxide band shows zero transmissivity at short distances. Based on analysis of the radiative transfer equation in this band, only the path radiance by air temperature survives. Brightness temperature of the received radiance can provide the raw air temperature and spectral average, followed by a spatial median-mean filter that can produce final air temperature images. Experiment results tested on a database obtained by a midwave extended FTIR system (Telops, Quebec City, QC, Canada) from February to July 2018 show a mean absolute error of 1.25 ∘ K for temperature range of 2.6−26.4 ∘ C. [ABSTRACT FROM AUTHOR]