Search results for "greenhouse"

Review of wind tunnel modelling of flow and pollutant dispersion within and from naturally ventilated livestock buildings

2021

[EN] Ammonia emissions from naturally ventilated livestock buildings (NVLBs) pose a serious environmental problem. However, the mechanisms that control these emissions are still not fully understood. One promising method for understanding these mechanisms is physical modelling in wind tunnels. This paper reviews studies that have used this method to investigate flow or pollutant dispersion within or from NVLBs. The review indicates the importance of wind tunnels for understanding the flow and pollutant dispersion processes within and from NVLBs. However, most studies have investigated the flow, while only few studies have focused on pollutant dispersion. Furthermore, only few studies have s…

Horizon scanning the European bio‐based economy: a novel approach to the identification of barriers and key policy interventions from stakeholders in…

2016

There is international recognition that developing a climate-smart bioeconomy is essential to the continuation of economic development, reduction of greenhouse gas emissions, and adaptation to climatic change; Bio-based products have an important role in making this transition happen. Supporting policy interventions have been put forward at European and national levels to support innovation and development of bio-based products and services. This study asks whether suggested policy interventions reflect the needs of stakeholders and examines how these needs vary between European regions. This consultation was performed through an online survey of 447 experts actively involved in bio-based r…

Unintended Effects of Energy Efficiency Policy: Lessons Learned in the Residential Sector

2021

The European Union has set an ambitious goal to tackle climate change, and energy efficiency in the residential sector is among the measures required to close the gap between targeted and actual greenhouse gas emissions. While different policy tools have been applied, the diffusion rate of these measures remains low. A system dynamics simulation model of the residential sector was developed to assess the advantages and drawbacks of energy efficiency policy in the multi-family building sector based on experience accumulated over the last twelve years in Latvia. The model was validated in expert group model building sessions and with historical trends. Simulating the model, a hypothesis was t…

Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate

2010

The processes controlling the carbon flux and carbon storage of the atmosphere, ocean and terrestrial biosphere are temperature sensitive and are likely to provide a positive feedback leading to amplified anthropogenic warming. Owing to this feedback, at timescales ranging from interannual to the 20-100-kyr cycles of Earth's orbital variations, warming of the climate system causes a net release of CO(2) into the atmosphere; this in turn amplifies warming. But the magnitude of the climate sensitivity of the global carbon cycle (termed gamma), and thus of its positive feedback strength, is under debate, giving rise to large uncertainties in global warming projections. Here we quantify the med…

Effects of substrate solarization on tomato soilless cultivation

2008

2020

Northern peatlands have accumulated large stocks of organic carbon (C) and nitrogen (N), but their spatial distribution and vulnerability to climate warming remain uncertain. Here, we used machine-learning techniques with extensive peat core data (n > 7,000) to create observation-based maps of northern peatland C and N stocks, and to assess their response to warming and permafrost thaw. We estimate that northern peatlands cover 3.7 ± 0.5 million km2 and store 415 ± 150 Pg C and 10 ± 7 Pg N. Nearly half of the peatland area and peat C stocks are permafrost affected. Using modeled global warming stabilization scenarios (from 1.5 to 6 °C warming), we project that the current sink of atmospheri…

The Tropical Forest Ecosystem: Reviewing the Effects of Deforestation on Climate and Environment

1991

The rapid decline of tropical rain forests in the 1980s, particularly caused by man-made forest clearance for farmland and timber exploitation, is accompanied by adverse climatic and environmental effects. In particular, rainfall and temperature conditions are adversely changed, with lower rainfall and high-er temperatures. Through deforestation, the atmospheric emissions of CO2 are increased and thus the global greenhouse effect is being strengthened. Tropical deforestation also increases soil erosion, depending upon the type of ecosystem. It also can be seen that floods more often occur in cases of deforestation. An international “action programme” for the protection and preservation of t…

Global sensitivity of aviation NO<sub>x</sub> effects to the HNO<sub>3</sub>-forming channel …

2013

Abstract. The impact of a recently proposed HNO3-forming channel of the HO2 + NO reaction on atmospheric ozone, methane and their precursors is assessed with the aim to investigate its effects on aviation NOx induced radiative forcing. The first part of the study addresses the differences in stratospheric and tropospheric HOx-NOx chemistry in general, by comparing a global climate simulation without the above reaction to two simulations with different rate coefficient parameterizations for HO2 + NO → HNO3. A possible enhancement of the reaction by humidity, as found by a laboratory study, particularly reduces the oxidation capacity of the atmosphere, increasing methane lifetime significantl…

Research on the Origin of Strawberry Plug Plants in Soilless Cultivation

2008

In recent years, the main advances in strawberry cultivation in Italy have regarded cultivation techniques, the use of alternatives to methyl bromide and the type of propagation material used. Fresh plants have taken over from cold-stored plants in 60% of cases. This prompted the need for new studies on the cultivation of fresh strawberry plants carried out in Sicilian nurseries. This report illustrates the results of a trial carried out in Sicily to find the best plug plants grown by four nurseries located at different altitudes (Madonie mountains, Sicani mountains, Nebrodi mountans) and on the plain (Marsala) and with an open cycle soilless system. The trial was carried out at our experim…

The study of climate change in Primary Education: an exploration from Social Science textbooks in the Valencian Community

2020

El cambio climático constituye uno de los principales desafíos socio-ambientales del actual siglo XXI. El objetivo de esta investigación es analizar los contenidos sobre el cambio climático que proponen los manuales escolares de Educación Primaria de Ciencias Sociales (3er ciclo) en la Comunidad Valenciana (España) atendiendo a: 1) la explicación del fenómeno (causas y consecuencias); y 2) la descripción de los principales gases de efecto invernadero. Los resultados indican que actualmente estos recursos proyectan una imagen excesivamente catastrófica sobre el cambio climático, especialmente por las consecuencias que se aluden (incremento de los fenómenos extremos atmosféricos) y citando co…