The spatial resolution of General Circulation Models (GCMs) is too coarse to represent regional climate changes at the scales required for environmental impact assessment. Therefore, downscaling of precipitation and temperature has to be carried out from the GCM grids to smaller scales of a few...

A simple model is presented for the dynamic calculation of the sludge blanket height and concentrations of suspended solids (diluted, sludge blanket and return sludge) in circular secondary settling tanks. The model combines a mass balance equation with three empirical equations, which account for...

The importance of the development and application of groundwater simulation mathematical models in the protection of aquifer systems is nowadays recognised as an undisputable fact. In this paper a mathematical model that was developed in order to simulate the operation of the Upper Anthemountas...

The objective of this study was to determine whether the use of the co-regionalization of the distanceto- river topographic variable with the soil properties topsoil clay and sand can improve their mapping. The interpolation techniques: ordinary kriging, kriging combined with regression (two models)...

The formation of chlorination by-products (CBPs) was investigated by bench-scale chlorination experiments with surface waters from different sources in Lesvos island, Greece. The main factors studied were organic matter content of water (expressed as UV-272 absorbance), time and chlorine dose. The...

A multi-layered three-dimensional hydrodynamic model has been developed to provide flow fields and water level changes in Hamilton Harbour. The field data collected in Hamilton Harbour during 1990 & 1991 field seasons was used for model verification. The simulated currents were compared with current...

This work illustrates the use and some related results of Artificial Neural Networks (ANNs) for data quality control of environmental time series and for reconstruction of missing data. ANNs are applied to the following problems: i) short and medium-term predicting of air pollutant concentrations in...

Atmospheric aerosols have been implicated in human health effects, visibility reduction in urban and regional areas, acidic deposition, and altering the earth’s radiation balance. A major goal of scientific research for the last fifteen years has been the development of the necessary models, using...

Pollution levels in an urban street-canyon area are determined numerically as part of the European research project OSCAR using the ADREA-HF code. Aim of the modeling is twofold: (i) to investigate the flow-field and carbon monoxide (CO) concentrations in the area and (ii) compare with measurements...

Artificial neural networks (ANNs) are being used increasingly to predict water variables. This study offers an alternative approach to quantify the relationship between time of chlorination in potable water (due to convectional treatment procedure) and chlorination by-products concentration...

In catchment hydrology, it is in practice impossible to measure everything we would like to know about the hydrological system, mainly due to high catchment heterogeneity and the limitations of measurement techniques. These limitations and the need to extrapolate information from the available...

An Upflow Anaerobic Sludge Bed (UASB) reactor was used to evaluate mesophilic anaerobic treatment of a pre-acidified fruit wastewater. The system was operated at increasing volumetric loading rates by sequentially increasing wastewater flowrate. The operational temperature was maintained initially...

One of the main environmental impacts of pig farms are the swine odours emitted from the various stages of the process. The main cause of odour emissions from pig farms are the anaerobic processes in manure. Numerous factors affect odour emissions such as diet, manure management and manure age. The...

In this study, the Bayesian approach is proposed to estimate the noise variances of Kalman filter based statistical models for predicting the daily averaged PM10 concentrations of a typical coastal city, Macau, with Latitude 22°10’N and Longitude 113°34’E. By using the measurements in 2001 and 2002...

Detailed meteorological data required for the equation of FAO-56 Penman-Monteith (P-M) method that was adopted by Food and Agriculture Organization (FAO) as a standard method in estimating reference evapotranspiration (ETo) are not often available, especially in developing countries. The Hargreaves...

An artificial neural network (ANN) model-based approach was developed and applied to estimate values of air temperature and relative humidity in remote mountainous areas. The application site was the mountainous area of the Samaria National Forest canyon (Greece). Seven meteorological stations were...

Human thermal comfort conditions were determined in two mountainous regions of Greece, Gerania mountains (MG) in east continental Greece, and mountainous Nafpaktia (MN) in west continental Greece. Both regions are unexploited with considerable tourist potential. Four sites in each study region were...

Activated carbon (AC) is currently being used to treat polychlorinated biphenyl (PCB) contaminated field sediment. In the presence of sediment, the sorption capacity of AC for PCBs can be reduced. In this study, sorption attenuation of AC is investigated using previously published data from 5...

The aim of the present paper is to give a systematic and critical presentation of important existing analytical solutions for transient stream-aquifer interaction, which can be used to give answers to simple interaction problems or to verify mathematical models. Stream-aquifer interaction is the...

A mathematical model to simulate microbial growth and lag time is proposed in the present work in accordance with Sengor et al. (2009). The model is verified experimentally for a mixed microbial culture growing at metal free and at Cr(III) or Cr(VI) contaminated environments. The model is further...

Radiocaesium is an isotope that can enter the food chain after having been absorbed by plants from soil. Our ability to predict the consequences of an accidental release of 137Cs depends mainly on the level of understanding of the mechanisms involved in 137Cs interactions with different components...

In order to accurately predict the pollutant concentrations and the plume trajectory in the atmosphere, it is necessary to take into account the effects of interactions between the plume and the surrounding environment. In fact, the atmospheric conditions have a lot of influence on the plume...

Urban air quality nowadays is one of the major environmental issues, due to its impact to various health problems, caused by the daily exposure of the population in dangerous air pollutants. The highest levels of air pollutants are usually observed in street canyons, emitted by urban traffic. To...

A teleconnection pattern has been identified between Eastern Mediterranean and Northwestern Europe in the geopotential fields of the upper troposphere (hereafter will be referred to as EMP) during winter and it seems to play significant role in the large-scale atmospheric circulation over...

The El Nino-Southern Oscillation is the dominant pattern of short-term climate variation, and is therefore of great importance in climate studies. Some recent studies showed the teleconnection between stream flow and the El-Nino Southern Oscillation (ENSO) of the equatorial Pacific Ocean. This paper...