A Model to Calculate Natural VOC Emissions from Forests in Europe

A significant portion of the total emissions of volatile organic compounds (VOC) may come from natural sources and, in particular, from forests. It is important to quantify these emissions because their share influences the magnitude of reductions that will have to be undertaken in the anthropogenic emission sectors in order to reduce secondary air pollution problem such as photochemical smog and acid deposition. This paper describes a model to calculate geographically-resolved VOC emissions from forests in Europe for different seasons, months or average days. We review briefly the method on how to calculate biogenic emissions from trees and available emission factor functions, including a discussion of the dependence of emissions on latitude, altitude, time of the day and temperature. Subsequently, the geographically-resolved forest and temperature data bases for Europe, as used in this model to derive the emission estimates, are described. The forest data are verified against other published forest inventories for Europe or parts of Europe. The resulting total VOC emissions are compared with existing country- or region-specific estimates, and some sensitivity analyses are carried out in order to show where the emission model could be simplified or where it needs to be improved. Based on our total forest coverage of approximately 2.2 million km^2, we calculate an average total annual emission rate of VOC's from these forests of 7.5 Megatonnes, based on typical European temperatures averaged over 30 years. This is equivalent to an areal average of 3.4 tonnes per year per km^2 forest or 0.9 tonnes per year per km^2 land area in the modeling domain. Until now, this forest emission model represents the only available basis for geographically-resolved emission calculations of VOC's from forests for all Europe for varying time periods

Calculation of Cause-specific Mortality Impacts of Fine Particulate Matter in GAINS

In the early 2000s, the GAINS (Greenhouse gas - Air pollution Interactions and Synergies) model used emerging epidemiological evidence to estimate premature mortality of the European population that can be attributed to the exposure to fine particulate matter and to identify cost-effective emission control strategies that reduce health impacts at least cost (Amann et al., 2011, p.accepted for publication). Based on the review of available studies on the health effects of PM conducted by the UNECE Task Force on Health (UNECE/WHO, 2003), the GAINS impact assessment employed the associations between population exposure to PM2.5 and all-cause mortality of the American Cancer Society study (Pope et al., 2002). In the meantime, a wealth of new epidemiological studies have sharpened the evidence about health effects of particulate matter and revealed more specific associations between ambient concentrations of PM2.5 and health impacts (e.g., Pope et al., 2009). In particular, new studies establish robust relationships between exposure to fine particles and specific causes of deaths. These new insights should facilitate a more specific estimate of the role of particular death causes that are associated with bad air quality, and a more precise estimate of the total mortality impacts in different countries as baseline death rates from different diseases vary over countries. This background paper describes a revised approach of the health impact assessment in GAINS that employs cause-specific concentration-response relationships for lung cancer, cardio-vascular and respiratory diseases for the European countries. Data on cause-specific deaths in the European countries have been extracted from the 2010 version of the World Health Organization database on mortality indicators by 67 causes of death, age and sex (HFA-MDB) for the latest available year. As a result, the cause-specific approach results in higher impact estimates than the former calculation for all-cause mortality. The difference depends on the relative shares of death causes in the various countries; for the EU-27, cause-specific calculations for the year 2000 result in 16% higher health effects, keeping all other factors constant (i.e., PM exposure, population, etc.). In the non-EU countries, the difference amounts to 54%, essentially due to the higher share of cardio-vascular deaths

Comparison of the RAINS Emission Control Cost Curves for Air Pollutants with Emission Control Costs Computed by the GAINS Model

This paper compares cost curves of SO2, NOx and PM2.5 emission controls generated with the RAINS (Regional Air Pollution Information and Simulation) model with cost estimates obtained from the GAINS (Greenhouse Gas - Air Pollution Interactions and Synergies) model. Based on the same set of input data, results from both models are very similar, and differences are considered as insignificant

IELTS and academic success in higher education: A UAE perspective

© 2016, Australian International Academic Centre PTY LTD. All rights reserved. This study compares the relationship between International English Language Testing System (IELTS) entrance scores and academic success as defined by general education program GPA for students at a federal university in the United Arab Emirates in order to reflect upon regional English language proficiency entrance requirements. It focuses on one group of students, direct entry students who have bypassed the English language foundation program with an overall IELTS 6.0 or greater and were admitted straight into the baccalaureate program. Students were grouped according to their IELTS proficiency levels: 6.0, 6.5 or ≥7.0. Measures of central tendency for overall GPA and academic-streamspecific GPA, along with the overall IELTS and the corresponding sub-scores were calculated. To test the statistical significance of any mean score GPA differences that existed between the 3 IELTS groups, a One-Way ANOVA was calculated. Based on the statistical analyses, the IELTS ≥7.0 group appears to have achieved a meaningful threshold for academic success in that they have consistently outperformed the other direct entry students. This finding corresponds to international entrance-requirement standards for non-native speakers of English

On the Optimization Model for Acid Loads on Forest Soils

The emphasis of the model is on the transboundary aspect of air pollution in Europe with the aim to find cost effective environment policies for Europe. The model will be embedded in the IIASA Regional Acidification Information and Simulation (RAINS) model. The spatial coverage of RAINS is all of Europe, and the time horizon begins in 1960 to permit checking of historical calculations, and extends to 2030 to allow examination of long-term consequences of control strategies. In this work we concentrate on soil acidification, which is an important link between air pollution and damage to the terrestrial and aquatic environment. The ability of soil to buffer acid deposition is a key factor in regulating the long-term surface and groundwater acidification. Soil acidification has also been related to forest die-back via its effect in the tree root zone. This work is concentrating on the finding of cost effective pollution control satisfying environment constraints, such as pH-value in forest soils

Towards a Simplified Model to Describe Ozone Formation in Europe

Air pollution is a multi-faceted problem with a variety of pollutants released from a large number of different anthropogenic activities causing a multitude of environmental effects. Cost-effective strategies to reduce negative impacts of air pollution must take account of these complexities and consider the individual aspects of the air pollution problem simultaneously. Integrated assessment models provide a consistent framework for a systematic analysis of alternative strategies. One of such models, the RAINS (Regional Acidification Information and Simulation) model developed at IIASA, has been used as a scientific support tool for the international discussions on further reductions of emissions of sulfur dioxide in Europe, which led in 1994 to an agreement on the 'Second Sulfur Protocol'. The perceived success of this agreement motivated further work on extending model analysis to additional pollutants and effects. Elevated levels of tropospheric ozone are currently considered as one of the major air quality problems in Europe, calling for balanced reductions of emissions of nitrogen oxides and volatile organic compounds. A major obstacle for developing a practical integrated assessment model for ozone is the complexity and the size of most of the current models on atmospheric ozone formation. This paper tries to identify elements for potential model simplifications, which could contribute to the development of an operational European-scale ozone formation model. Such a simplified model would establish the core of an integrated assessment model for ozone formation, linking information on emissions and emission control costs with an assessment of their environmental impacts