Search results for "Warming"
showing 10 items of 339 documents
Is the Spectacled WarblerSylvia conspicillataexpanding northward because of climate warming?
2014
Capsule The Spectacled Warbler shows a strictly Mediterranean distribution which is expected to expand northward in response to climate warming. To test this hypothesis, we defined the regular distribution of the species based on the literature and we tested whether: (1) spring temperatures in this area significantly increased between 1967 and 2010; (2) breeding attempts north of the regular range occurred progressively at northern latitudes. Both of these hypotheses were confirmed, supporting the hypothesis that the species is expanding northward because of climate warming.
Foreseeable global warming will differentially affect Chara vulgaris populations from different altitudes
2015
Abstract A 2–4 °C increase in temperature is foreseen for the Mediterranean region by the end of the 21st century due to climate change. This warming is expected to occur as heat waves, and will be particularly important for shallow water bodies which are the main freshwater ecosystems in the Mediterranean. We subjected four populations of Chara vulgaris to a common garden experiment. Each population came from locations at different altitudes, hence living at different mean temperatures. Individual charophyte cultures were initiated with specimens from four origins and acclimatized at 20 °C in a controlled environment for 3 weeks. After this, all the populations were incubated under 3 water…
Ranking drivers of global carbon and energy fluxes over land
2015
The accurate estimation of carbon and heat fluxes at global scale is paramount for future policy decisions in the context of global climate change. This paper analyzes the relative relevance of potential remote sensing and meteorological drivers of global carbon and energy fluxes over land. The study is done in an indirect way via upscaling both Gross Primary Production (GPP) and latent energy (LE) using Gaussian Process regression (GPR). In summary, GPR is successfully compared to multivariate linear regression (RMSE gain of +4.17% in GPP and +7.63% in LE) and kernel ridge regression (+2.91% in GPP and +3.07% in LE). The best GP models are then studied in terms of explanatory power based o…
Climate change effects on the hydrological regime of small non-perennial river basins.
2015
Recent years have been witnessing an increasing interest on global climate change and, although we are only at the first stage of the projected trends, some signals of climate alteration are already visible. Climate change encompasses modifications in the characteristics of several interrelated climate variables, and unavoidably produces relevant effects on almost all the natural processes related to the hydrological cycle. This study focuses on potential impacts of climate variations on the streamflow regime of small river basins in Mediterranean, seasonally dry, regions. The paper provides a quantitative evaluation of potential modifications in the flow duration curves (FDCs) and in the p…
Influence of carbon to nitrogen ratio on nitrous oxide emission in an Integrated Fixed Film Activated Sludge Membrane BioReactor plant
2018
Abstract In this study a University of Cape Town (UCT) Integrated Fixed Film Activated Sludge (IFAS) Membrane BioReactor (MBR) wastewater treatment plant was monitored in terms of nitrous oxide (N2O) emissions. The short term effect on the N2O emission due to the influent carbon-to-nitrogen (C/N) ratio variation (C/N ratios of 2, 5 and 10 gCOD/gN) was evaluated. Since in a previous study, the effect of the C/N ratio was studied in the same system without biofilm (UCT-MBR configuration) the main aim here was to investigate the role of biofilms on N2O emissions. Under all the investigated C/N ratios, the N2O fluxes and the average emission factors were lower than that of previous studies with…
Economic analysis of the scale-up and implantation of a hollow fibre membrane contactor plant for nitrogen recovery in a full-scale wastewater treatm…
2021
[EN] Nitrogen recovery technologies such as the hollow fibre membrane contactor are now being developed. However, an economic analysis is needed prior to their full-scale application in wastewater treatment plants. The aim of this study was to analyse the economic and environmental aspects of scaling-up this method. To achieve it, a full-scale 40,000 m3·day¿1-wastewater treatment plant influent flow rate was simulated jointly with a membrane contactor plant to evaluate the minimum costs of optimum operating conditions of membrane contactors (pH, feed flow rate and membrane surface). The optimum conditions for treating 600 m3·day¿1 of reject water was found to be 10 pH, 0.08 m3·s¿1 feed flow…
Hot towels
2023
Background Meibomian gland dysfunction (MGD) reduces quality-of-life and hinders work productivity of millions of patients, with high direct and indirect societal costs. Thickened meibum obstructs the glands and disrupts ocular surface health. Heating the eyelids to soften and express meibum from the glands can be beneficial. The most accessible method for eyelid warming uses heated, wet towels. However, the efficacy of this treatment is reliant on the methodology, and evidence-based best-practice recommendations are needed. Purpose To evaluate the literature on hot towels in MGD treatment and recommend a best-practice protocol for future research and patient treatment. Methods Studies were…
Infrared monitoring of underground CO2 storage using chalcogenide glass fibers
2009
International audience; An optical-fiber-based system suitable for monitoring the presence of carbon dioxide, so-called "greenhouse gas", is investigated. Since each pollutant gas shows a characteristic optical absorption spectrum in the mid-infrared (mid-IR), it is possible to detect selectively and quantitatively the presence of gases in a given environment by analysing mid-IR spectra. The main infrared signature of carbon dioxide gas is a double absorption peak located at 4.2 μm. Chalcogenide optical fibers, which can transmit light in the 1-6 μm range, are well-adapted for CO2 analysis. In this wavelength range, they show attenuation losses that compare favourably with other types of fi…
A Proposed Methodology to Control Body Temperature in Patients at Risk of Hypothermia by means of Active Rewarming Systems
2014
Hypothermia is a common complication in patients undergoing surgery under general anesthesia. It has been noted that, during the first hour of surgery, the patient’s internal temperature (Tcore) decreases by 0.5–1.5°C due to the vasodilatory effect of anesthetic gases, which affect the body’s thermoregulatory system by inhibiting vasoconstriction. Thus a continuous check on patient temperature must be carried out. The currently most used methods to avoid hypothermia are based on passive systems (such as blankets reducing body heat loss) and on active ones (thermal blankets, electric or hot-water mattresses, forced hot air, warming lamps, etc.). Within a broader research upon the environment…
Long-term climate variability in continental subarctic Canada: A 6200-year record derived from stable isotopes in peat
2010
The rapid warming of arctic regions during recent decades has been recorded by instrumental monitoring, but the natural climate variability in the past is still sparsely reconstructed across many a ...