An assessment of the likelihood of contrail formation 

2021 ◽  
Author(s):  
Giacomo Caria ◽  
Sara Dal Gesso
Keyword(s):  
Environmental Issues ◽  
Climate Impact ◽  
Mitigation Strategies ◽  
Air Transport ◽  
Horizon 2020 ◽  
Sulphate Aerosols ◽  
Long Time ◽  
Aviation Emissions ◽  
Carbon Dioxide Co2 ◽  
Different Altitudes

<p>Air Transport has for a long time been linked to environmental issues like pollution, noise and climate change. Aviation emissions, such as carbon dioxide (CO2), water vapour (H2O), nitrogen oxides (NOx), soot and sulphate aerosols, alter the concentration of atmospheric Greenhouse gases and trigger the formation of contrails and cirrus clouds. The ClimOP collaboration, an Horizon 2020 project, aims to identify, evaluate and support the implementation of mitigation strategies to initiate and foster operational improvements which reduce the climate impact of the aviation sector. To this end, we present a study that assesses the likelihood of contrail formation as a function of key atmospheric variables, at different altitudes.</p>

scholarly journals Internet page content analysis of north European Sea ports

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Olli-Pekka Hilmola ◽  
Andres Tolli ◽  
Ain Kiisler
Keyword(s):  
Content Analysis ◽  
Environmental Issues ◽  
Basic Design ◽  
Time Period ◽  
Long Time ◽  
Sea Ports ◽  
Selection Of

Abstract This study analyses 98 Internet pages of sea ports located in Sweden, Finland and Estonia during years 2017–2019. Aim of the study is to find, how website basic design is completed (colours and languages), how slogans, environmental issues, statistics and hinterland transports are reported. Based on the analysis, it appears as rather common that sea ports follow conservative selection of colours in their websites, where blue and white are clearly most popular. Typically, English and Swedish are as the most common used language, followed by Finnish, Russian and Estonian. In some rare cases, websites are offered in Chinese or German. Larger sea ports do have clear “slogans”, where smaller ones are just having lengthy justification for their existence. Environmental issues are increasing concern among sea ports, and these are mostly mentioned in details within Swedish actors. Providing statistics varies among companies, and in some sea ports these are provided from very long time period, where in others from just previous years or then only from last year (or even at all). It is common for companies to report that they have sustainable hinterland access, railway available.

Insights into the Development of Cu-based Photocathodes for Carbon Dioxide (CO2) Conversion

2021 ◽  
Author(s):  
Wenzhang Li ◽  
Keke Wang ◽  
yanfang Ma ◽  
Yang Liu ◽  
Weixin Qiu ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Fossil Fuels ◽  
Environmental Issues ◽  
Energy Crisis ◽  
Co2 Conversion ◽  
Carbon Dioxide Co2 ◽  
Reduction Of Co2

The ever-growing factitious over-consumption of fossil fuels and the accompanying massive emissions of CO2 have caused severe energy crisis and environmental issues. Photoelectrochemical (PEC) reduction of CO2 that can combine...

scholarly journals Influences of Single-Lane Automatic Driving Systems on Traffic Efficiency and CO2 Emissions on China’s Motorways

2021 ◽  
Vol 11 (22) ◽  
pp. 11032
Author(s):  
Haokun Song ◽  
Fuquan Zhao ◽  
Zongwei Liu
Keyword(s):  
Co2 Emissions ◽  
Penetration Rate ◽  
Connected Vehicles ◽  
Driving System ◽  
Traffic Efficiency ◽  
Automatic Driving ◽  
Driving Behaviors ◽  
Road Capacity ◽  
Long Time ◽  
Carbon Dioxide Co2

There are big differences between the driving behaviors of intelligent connected vehicles (ICVs) and traditional human-driven vehicles (HVs). ICVs will be mixed with HVs on roads for a long time in the future. Different intelligent functions and different driving styles will affect the condition of traffic flow, thereby changing traffic efficiency and emissions. In this paper, we focus on China’s expressways and secondary motorways, and the impacts of the ‘single-lane automatic driving system’ (SLADS) on traffic delay, road capacity and carbon dioxide (CO2) emissions were studied under different ICV penetration rates. Driving styles were regarded as important factors for scenario analysis. We found that with higher volume input, SLADS has an optimizing effect on traffic efficiency and CO2 emissions generally, which will be more significant as the ICV penetration rate increases. Additionally, enhancing the aggressiveness of driving behavior appropriately is an effective way to amplify the benefits of SLADS.

scholarly journals Multi-Year Comparison of CO2 Concentration from NOAA Carbon Tracker Reanalysis Model with Data from GOSAT and OCO-2 over Asia

2020 ◽  
Vol 12 (15) ◽  
pp. 2498
Author(s):  
Farhan Mustafa ◽  
Lingbing Bu ◽  
Qin Wang ◽  
Md. Arfan Ali ◽  
Muhammad Bilal ◽  
...  
Keyword(s):  
Time Series ◽  
Spatial Distribution ◽  
Atmospheric Carbon Dioxide ◽  
Carbon Budget ◽  
Co2 Concentration ◽  
Mitigation Strategies ◽  
Spatial Correlations ◽  
Western Asia ◽  
Carbon Dioxide Co2 ◽  
Good Agreement

Accurate knowledge of the carbon budget on global and regional scales is critically important to design mitigation strategies aimed at stabilizing the atmospheric carbon dioxide (CO2) emissions. For a better understanding of CO2 variation trends over Asia, in this study, the column-averaged CO2 dry air mole fraction (XCO2) derived from the National Oceanic and Atmospheric Administration (NOAA) CarbonTracker (CT) was compared with that of Greenhouse Gases Observing Satellite (GOSAT) from September 2009 to August 2019 and with Orbiting Carbon Observatory 2 (OCO-2) from September 2014 until August 2019. Moreover, monthly averaged time-series and seasonal climatology comparisons were also performed separately over the five regions of Asia; i.e., Central Asia, East Asia, South Asia, Southeast Asia, and Western Asia. The results show that XCO2 from GOSAT is higher than the XCO2 simulated by CT by an amount of 0.61 ppm, whereas, OCO-2 XCO2 is lower than CT by 0.31 ppm on average, over Asia. The mean spatial correlations of 0.93 and 0.89 and average Root Mean Square Deviations (RMSDs) of 2.61 and 2.16 ppm were found between the CT and GOSAT, and CT and OCO-2, respectively, implying the existence of a good agreement between the CT and the other two satellites datasets. The spatial distribution of the datasets shows that the larger uncertainties exist over the southwest part of China. Over Asia, NOAA CT shows a good agreement with GOSAT and OCO-2 in terms of spatial distribution, monthly averaged time series, and seasonal climatology with small biases. These results suggest that CO2 can be used from either of the datasets to understand its role in the carbon budget, climate change, and air quality at regional to global scales.

scholarly journals Climate benefits of proposed carbon dioxide mitigation strategies for international shipping and aviation

2019 ◽  
Vol 19 (23) ◽  
pp. 14949-14965 ◽  
Author(s):  
Catherine C. Ivanovich ◽  
Ilissa B. Ocko ◽  
Pedro Piris-Cabezas ◽  
Annie Petsonk
Keyword(s):  
Carbon Dioxide ◽  
Co2 Emissions ◽  
Mitigation Strategies ◽  
Mitigation Measures ◽  
Civil Aviation ◽  
Economic Sectors ◽  
International Shipping ◽  
Nationally Determined Contributions ◽  
Reduce Carbon Dioxide ◽  
Carbon Dioxide Co2

Abstract. While individual countries work to achieve and strengthen their nationally determined contributions (NDCs) to the Paris Agreement, the growing emissions from two economic sectors remain largely outside most countries' NDCs: international shipping and international aviation. Reducing emissions from these sectors is particularly challenging because the adoption of any policies and targets requires the agreement of a large number of countries. However, the International Maritime Organization (IMO) and the International Civil Aviation Organization (ICAO) have recently announced strategies to reduce carbon dioxide (CO2) emissions from their respective sectors. Here we provide information on the climate benefits of these proposed measures, along with related potential measures. Given that the global average temperature has already risen 1 ∘C above preindustrial levels, there is only 1.0 or 0.5 ∘C of additional “allowable warming” left to stabilize below the 2 or 1.5 ∘C thresholds, respectively. We find that if no actions are taken, CO2 emissions from international shipping and aviation may contribute roughly equally to an additional combined 0.12 ∘C to global temperature rise by end of century – which is 12 % and 24 % of the allowable warming we have left to stay below the 2 or 1.5 ∘C thresholds (1.0 and 0.5 ∘C), respectively. However, stringent mitigation measures may avoid over 85 % of this projected future warming from the CO2 emissions from each sector. Quantifying the climate benefits of proposed mitigation pathways is critical as international organizations work to develop and meet long-term targets.

scholarly journals Speech can produce jet-like transport relevant to asymptomatic spreading of virus

2020 ◽  
Vol 117 (41) ◽  
pp. 25237-25245 ◽  
Author(s):  
Manouk Abkarian ◽  
Simon Mendez ◽  
Nan Xue ◽  
Fan Yang ◽  
Howard A. Stone
Keyword(s):  
Social Interactions ◽  
Disease Transmission ◽  
Laboratory Experiments ◽  
Scaling Laws ◽  
Mitigation Strategies ◽  
Directed Transport ◽  
Transport Distance ◽  
Long Time ◽  
Phonetic Features

Many scientific reports document that asymptomatic and presymptomatic individuals contribute to the spread of COVID-19, probably during conversations in social interactions. Droplet emission occurs during speech, yet few studies document the flow to provide the transport mechanism. This lack of understanding prevents informed public health guidance for risk reduction and mitigation strategies, e.g., the “6-foot rule.” Here we analyze flows during breathing and speaking, including phonetic features, using orders-of-magnitude estimates, numerical simulations, and laboratory experiments. We document the spatiotemporal structure of the expelled airflow. Phonetic characteristics of plosive sounds like “P” lead to enhanced directed transport, including jet-like flows that entrain the surrounding air. We highlight three distinct temporal scaling laws for the transport distance of exhaled material including 1) transport over a short distance (<0.5 m) in a fraction of a second, with large angular variations due to the complexity of speech; 2) a longer distance, ∼1 m, where directed transport is driven by individual vortical puffs corresponding to plosive sounds; and 3) a distance out to about 2 m, or even farther, where sequential plosives in a sentence, corresponding effectively to a train of puffs, create conical, jet-like flows. The latter dictates the long-time transport in a conversation. We believe that this work will inform thinking about the role of ventilation, aerosol transport in disease transmission for humans and other animals, and yield a better understanding of linguistic aerodynamics, i.e., aerophonetics.

scholarly journals Effects of Different Pre-processing Methods on Dry Anaerobic Fermentation of Sugarcane Leaves and Pig Manure

2020 ◽  
Vol 145 ◽  
pp. 02065
Author(s):  
Xiaohong Huang ◽  
Jing Jiao ◽  
Jihua Du ◽  
Zunxiang Li
Keyword(s):  
Loading Rate ◽  
Anaerobic Fermentation ◽  
Biogas Production ◽  
Environmental Issues ◽  
Pig Manure ◽  
Production Volume ◽  
Volume Loading ◽  
Processing Methods ◽  
Long Time ◽  
Fermentation Period

Using agricultural wastes for anaerobic fermentation to produce biogas can not only realize the resource utilization of the wastes, but also prevent the environmental issues caused by straw burning. Sugarcane leaves contain waxy layer, which will cause problems such as difficulty in degradation, long-time fermentation and low biogas production. This paper studies the effects on three pre-processing methods of adding rush rot agent, natural retting for 7 days and water moisture for 24 hours of dry anaerobic fermentation of sugarcane leaves and pig manure. The results show that natural retting for 7 days has the advantage of daily biogas production when the fermentation period is less than 20 days, but this method is not obviously different from that of water moisture for 24 hours. When taking total biogas production volume and volume loading rate as the indicators, water moisture for 24 hours is the best pre-processing method for dry anaerobic fermentation of sugarcane leaves and pig manure when the fermentation period is more than 20 days.

scholarly journals Estimating net climate impacts of timber production and utilization in fossil fuel intensive material and energy substitution

2017 ◽  
Vol 47 (8) ◽  
pp. 1010-1020 ◽  
Author(s):  
Ashraful Alam ◽  
Harri Strandman ◽  
Seppo Kellomäki ◽  
Antti Kilpeläinen
Keyword(s):  
Forest Management ◽  
Life Span ◽  
Fossil Fuel ◽  
Assessment Tool ◽  
Forest Biomass ◽  
Climate Impact ◽  
Climate Impacts ◽  
Mitigation Strategies ◽  
Climate Mitigation ◽  
Similar System

We utilized an ecosystem model and life cycle assessment tool for studying carbon flows between the ecosystem, technosystem, and atmosphere for scenarios utilizing forest biomass (biosystem) against fossil fuel intensive materials (fossil system). The net climate impacts were studied for a Norway spruce (Picea abies (L.) Karst.) stand over two consecutive rotation periods (2 × 80 years) in the boreal conditions in central Finland (62°N, 29°E). The effects of alternative forest management on the carbon dynamics in the biosystem were studied in comparison with the fossil system by using an unmanaged and baseline thinning regime. The results showed that the biosystem produced carbon benefits compared with the similar system with the use of fossil fuel intensive materials and energy. The unmanaged stand stored the highest amount of carbon and retained carbon the longest when solely the ecosystem was considered. Studying the ecosystem and the technosystem together, the biosystem was found effective in storing and increasing the residence of carbon with or without changing the life span of biomass-based products. We found that the increase of the life span of biomass-based products could reduce emissions up to 0.28 t CO2·ha−1·year−1 depending on the management regimes over the study period. The increased stocking regimes could increase negative net climate impact by 47% over the study period compared with the use of baseline thinning in the biosystem. The proper climate mitigation strategies should consider the benefits from forest management and forest biomass in storing carbon into both the ecosystem and technosystem.

Correlations of methane and carbon dioxide concentrations from feedlot cattle as a predictor of methane emissions

2016 ◽  
Vol 56 (1) ◽  
pp. 108 ◽  
Author(s):  
Mei Bai ◽  
David W. T. Griffith ◽  
Frances A. Phillips ◽  
Travis Naylor ◽  
Stephanie K. Muir ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Concentration Ratio ◽  
Co2 Concentration ◽  
Feedlot Cattle ◽  
Mitigation Strategies ◽  
Co2 Production ◽  
Ch4 Emissions ◽  
Carbon Dioxide Concentrations ◽  
Carbon Dioxide Co2 ◽  
Animal Diet

Accurate measurements of methane (CH4) emissions from feedlot cattle are required for verifying greenhouse gas (GHG) accounting and mitigation strategies. We investigate a new method for estimating CH4 emissions by examining the correlation between CH4 and carbon dioxide (CO2) concentrations from two beef cattle feedlots in Australia representing southern temperate and northern subtropical locations. Concentrations of CH4 and CO2 were measured at the two feedlots during summer and winter, using open-path Fourier transform infrared spectroscopy. There was a strong correlation for the concentrations above background of CH4 and CO2 with concentration ratios of 0.008 to 0.044 ppm/ppm (R2 >0.90). The CH4/CO2 concentration ratio varied with animal diet and ambient temperature. The CH4/CO2 concentration ratio provides an alternative method to estimate CH4 emissions from feedlots when combined with CO2 production derived from metabolisable energy or heat production.

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