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One of the most important aspects of working in an office environment is ensuring that the space has optimal thermal comfort and an indoor environment. The aim of this research is to investigate the thermal comfort and indoor climate in three office rooms located at one of the campus buildings at the University of Gävle, Sweden. The evaluated period is in the month of April during springtime. During this period, parameters such as temperature, relative humidity, CO2, supply air flow rate, and room air velocities are measured on site. The results of the measurement show that the indoor temperature is on average lower in the rooms facing north, at 21–23.5 °C, compared to the rooms facing south, which reach high temperatures during sunny days, up to 26 °C. The results also show that the ventilation air supply rate is lower than the requirement for offices in two of the office rooms. The ACH rate is also low, at ≈ 1 h−1 for all the rooms, compared to the required levels of 2–4 h−1. The CO2 levels are within the recommended values; on average, the highest is in one of the south-facing rooms, with 768 ppm, and the maximum measured value is also in the same room, with 1273 ppm for a short period of time. [ABSTRACT FROM AUTHOR]

A simulation study based on recent regional climate scenarios for Sweden investigated possible changes in carbon (C) dynamics and net ecosystem exchange (NEE) of Swedish Norway spruce forest ecosystems. Four sites, representative of well-drained soils in four regions, were included. Stand development was simulated for a 100-year rotation period using a coupled model describing abiotic and biotic processes in the soil-plant-atmosphere system. Two IPCC climate change scenarios, corresponding to a mean annual temperature increase of about 2°C (A2) or 3°C (B2) from the reference period 1961–1990 to a new period 2061–2090, were considered. Annual maximum snow depth decreased with the increase in air temperature, whereas maximum soil frost depth and mean annual soil temperature showed only small changes, especially for the sites in northern Sweden. Simulations suggested that in the warmer climate, gross primary production (GPP) increased by 24–32% in northern Sweden and by 32–43% in the south. In the north, the increase was related to the combined effect of air and soil temperature extending the growing season, whereas in the south it was mainly governed by increased N availability due to increased soil temperature. NEE increased by about 20% (A2) or 25% (B2) at all sites, more or less solely due to increased accumulation of C in the tree biomass (including harvest residues), since changes in soil C were small compared with the current climate. Both light use efficiency and water use efficiency were improved in the future climate scenarios, despite increases in atmospheric CO2 not being considered. [ABSTRACT FROM AUTHOR]

Summary • Growth and nitrogen (N) economy of mountain birch are reported here in response to temperature change. Mechanisms of temperature effects on plant growth in temperate–arctic regions are discussed in the light of decreasing growth rates and increasing leaf-N contents along altitudinal and latitudinal temperature gradients. • Mountain birch ( Betula pubescens ssp. czerepanovii) seedlings were grown at two soil temperatures, air temperatures and nutrient concentrations in a full-factorial experiment during one growing season in northern Sweden. • Changes in air and soil temperature affected aboveground growth more than belowground growth. An increase in air temperature increased leaf area ratio and plant-N productivity while decreasing plant-N concentration and leaf-N content. A change in soil temperature affected root-N uptake rate and plant-N concentration, similar to the effect of a change in nutrient supply. Air and soil temperature had interactive effects on growth rate, N productivity and leaf-N content. • The results indicate that increasing leaf-N content with increasing altitude and latitude is not only a passive consequence of weaker N dilution by reduced growth, but also a physiological acclimation to lower air temperature. [ABSTRACT FROM AUTHOR]