Saeid Eslamian

Bio: Saeid Eslamian is an academic researcher from Isfahan University of Technology. The author has contributed to research in topics: Rainwater harvesting & Climate change. The author has an hindex of 28, co-authored 335 publications receiving 3767 citations. Previous affiliations of Saeid Eslamian include Princeton University.

Surface irrigation simulation models: a review

Abstract: This paper reviews the literature and results of more than one hundred published articles in scientific journals with respect to simulation of surface irrigation. The results showed that 53.4% of the simulations belong to furrow systems. It is 35.9% for border systems and 10.7% for basin irrigation. However, satisfactory simulations were 70.3%, 63.6%, and 54.5% for border, basin, and furrow systems, respectively. The priority of irrigation methods to simulate using hydrodynamic (HD) and other models is border, basin, and furrow irrigation. It is border, furrow, and basin for kinematic wave (KW) and volume balance (VB) models. Finally, this priority is basin, border, and furrow for zero inertia (ZI) model. Meanwhile, the models estimated advance and infiltration phases better than recession and runoff phases during an irrigation event.

Analysis of potential evapotranspiration using 11 modified temperature-based models

Abstract: The evapotranspiration was estimated using 11 temperature-based models and was compared with the FAO Penman-Monteith model The results showed that the modified Hargreaves-Samani models estimate the evapotranspiration better than the other models in the most provinces of Iran However, the values of R2 were less than 098 for 15 provinces of Iran Therefore, the models were calibrated and precision of estimation was increased (the values of R2 were less than 100 (with respect to two decimal numbers) for only five provinces in the modified models) The temperature-based models estimated the evapotranspiration in the north east and south west provinces of Iran better than other provinces The best precise methods were the modified Hargreaves-Samani 1 method for AL (before calibration) and the Hargreaves-Samani method for AR, the Modified Hargreaves-Samani 2 method for SE and GH, the modified Hargreaves-Samani 1 for FA, and the modified Hargreaves-Samani 3 for MZ (after calibration)

Climate Change 2007: Impacts, Adaptation and Vulnerability.

Abstract: Impatti, adattamento e vulnerabilita Le cause e le responsabilita dei cambiamenti climatici sono state trattate sul numero di ottobre della rivista Cda. Approfondiamo l’argomento presentando il documento: “Cambiamenti climatici 2007: impatti, adattamento e vulnerabilita” votato ad aprile 2007 dal secondo gruppo di lavoro del Comitato Intergovernativo sui Cambiamenti Climatici (Intergovernmental Panel on Climate Change). Si tratta del secondo di tre documenti che compongono il quarto rapporto sui cambiamenti climatici.

The Ensemble Kalman Filter: Theoretical formulation and practical implementation

Abstract: The purpose of this paper is to provide a comprehensive presentation and interpretation of the Ensemble Kalman Filter (EnKF) and its numerical implementation. The EnKF has a large user group, and numerous publications have discussed applications and theoretical aspects of it. This paper reviews the important results from these studies and also presents new ideas and alternative interpretations which further explain the success of the EnKF. In addition to providing the theoretical framework needed for using the EnKF, there is also a focus on the algorithmic formulation and optimal numerical implementation. A program listing is given for some of the key subroutines. The paper also touches upon specific issues such as the use of nonlinear measurements, in situ profiles of temperature and salinity, and data which are available with high frequency in time. An ensemble based optimal interpolation (EnOI) scheme is presented as a cost-effective approach which may serve as an alternative to the EnKF in some applications. A fairly extensive discussion is devoted to the use of time correlated model errors and the estimation of model bias.

Cation exchange capacity.

Abstract: Positive ions that are available in soils absorb on grain surfaces. The total sum of cations that can be absorbed bij a soil/sediment at a certain PH is defined by the cation-exchange capacity (CEC, in meq g-1: mol equivalents per gram). The uptake of cations is an important parameter in agriculture and the larger the CEC, the more cations can be absorbed to the soil. The CEC depends highly on the pH of soil and sediments, where the CEC decreases with decreasing PH (increasing acidity). The exchange of ions on sediments occurs commonly fast on geological time scales, but the kinetics of adsorption in natural environments is still poorly understood. The strength of the bonding between the cations and the sediments varies from weak Van der Waals bondings (physical adsorption) to strong chemical bonds. The CEC is widely used for agricultural assessment because it is a measure of general soil fertility as well as an indicator of structural stability because CED is capabel of enhancing development of shrinkage cracks. The list below shows the CEC for different types of minerals. The data indicate that the CEC can vary over 2 orders of magnitude for various types of , minerals and can vary one order of magnitude within one soil type. Cation exchange capacity for different types of sediment (Eisma, 1992; Locher and de Bakker, 1990):