Search for: lakes
Total 86 records
Article World Environmental and Water Resources Congress 2012: Crossing Boundaries, Proceedings of the 2012 Congress ; 2012 , Pages 1917-1926 ; 9780784412312 (ISBN) ; Ahmadalipour, A ; Shafiee Jood, M ; Tajrishy, M ; Abrishamchi, A ; Environ. Water Resour. Inst. (EWRI) Am. Soc. Civ. Eng ; Sharif University of Technology
Urmia Lake is a large hyper-saline lake located in the northwest of Iran. It plays an important role in the hydrology, climate and ecology of its surrounding regions. In recent years, the water level of Urmia Lake has been dropped significantly. This study investigates the seasonal and annual variations of the lake area from 2000 to 2011 using remote sensing data. MODIS imageries of Normalized Differential Vegetation Index (NDVI) were used to extract the water surface area of the lake. Results reveal a significant decline in the lake area during the last past 12 years. Analysis of the seasonal images shows that maximum and minimum areas of Urmia Lake usually occur in winter and autumn,...
Monitoring temperature changes in a hypersaline lake using MODIS-derived water temperatures (the case of Urmia Lake, Iran), Article 6th International Symposium on Environmental Hydraulics, Athens, 23 June 2010 through 25 June 2010 ; Volume 2 , 2010 , Pages 881-886 ; 9780415595469 (ISBN) ; Tajrishy, M ; Sharif University of Technology
Lake surface temperature is an important indicator of the lake state and a driver of regional weather and climate near large lakes. The objective of this study is to use thermal imagery from the MODIS on board the Earth Observing System Terra and Aqua platforms to assess the spatial and temporal variations in Urmia lake temperature. Urmia Lake, located in northwestern Iran is one of the largest permanent hypersaline lakes in the world. The surface temperature of Urmia Lake is examined between 2008 and 2009, as dry years. MODIS-derived lake SWT then was calibrated with monthly observations. MODIS-derived lake SWT exhibits a cool bias (-0.72°C) relative to in situ temperature observations in...
M.Sc. Thesis Sharif University of Technology ; Abrishamchi, Ahmad
The Urmia Lake in the north west of Iran and one of the most important habitats in the world is in danger of drying. Drought of recent years, increasing of temperature and evaporation and also construction of several dams in Urmia Lake basin can be considered as the main factors of decreasing the Lake level. Simultaneous forecasts of lake level and inflow streams help us to make better decisions for allocating and releasing enough water for environmental demands such as Urmia Lake. This study aims to determine relationships between historical information of basin with streamflow of Ajichai and Urmia Lake level, and use them for predicting the further conditions. In this process, streamflow...
Article Dynamics of Atmospheres and Oceans ; Vol. 65, issue , 2014 , pp. 1-16 ; ISSN: 03770265 ; Jamali, M ; Sharif University of Technology
In this paper we examine how exchange flow in Urmia Lake plays a crucial role in dynamics of the lake. Urmia Lake, a very large hyper-saline lake of high ecological significance, is located in northwest of Iran with a 15-km causeway dividing it into north and south lakes. A 1250-m opening in the causeway near the east coast links the two lakes. The differences in mean water levels and densities of the two lakes increase in spring due to large freshwater inflows into the south lake. High evaporation dominates the lake in summer. By incorporating the results of a two-layer hydraulics theory into a mixing model of the lake, we show that the exchange flow through the opening diminishes the water...
Impact of middle eastern dust sources on PM10 in iran: highlighting the impact of tigris-euphrates basin sources and lake urmia desiccation, Article Journal of Geophysical Research: Atmospheres ; Volume 121, Issue 23 , 2016 , Pages 14,018-14,034 ; 2169897X (ISSN) ; Salim, R ; Arhami, M ; Sharif University of Technology
Blackwell Publishing Ltd 2016
Contribution of different Middle Eastern dust origins to PM10 (PM with aerodynamic diameters less than 10 µm) levels in several receptor large cities in Iran was investigated. Initially, the major regional dust episodes were determined through statistical analysis of recorded PM levels at air quality stations and verified using satellite images. The particles dispersion was simulated by Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) to regenerate PM10 during the dust episodes. The accuracy of the modeled results was rather convincing, with an average squared correlation coefficient (R2) of 0.7 (max = 0.95). Consequently, the contributions of different dust sources to the...
Interaction of lake-groundwater levels using cross-correlation analysis: A case study of Lake Urmia Basin, Iran, Article Science of the Total Environment ; 2020 , Volume 729 ; Ataie Ashtiani, B ; Hosseini, S. M ; Simmons, C. T ; Sharif University of Technology
Elsevier B.V 2020
Lake Urmia (LU) is the second largest hypersaline lake in the world. Lake Urmia's water level has dropped drastically from 1277.85 m to 1270.08 m a.s.l (equal to 7.77 m) during the last 20 years, equivalent to a loss of 70% of the lake area. The likelihood of lake-groundwater connection on the basin-scale is uncertain and understudied because of lack of basic data and precise information required for physically-based modeling. In this study, cross-correlation analysis is applied on a various time-frames of water level of the lake and groundwater levels (2001–2018) recorded in 797 observation wells across 17 adjacent aquifers. This provides insightful information on the lake-groundwater...
Article Journal of Great Lakes Research ; Volume 39, Issue 1 , March , 2013 , Pages 90-99 ; 03801330 (ISSN) ; Tajrishy, M ; Sharif University of Technology
Urmia Lake in the northwest of Iran is the second largest hyper-saline lake worldwide. During the past two decades, a significant water level decline has occurred in the lake. The existing estimations for the lake water balance are widely variable because the lake bathymetry is unknown. The main focus of this study is to extract the volume-area-elevation (V-A-L) characteristics of Urmia Lake utilizing remote sensing data and analytical models. V-A-L equations of the lake were determined using radar altimetry data and their concurrent satellite-derived surface data. Next, two approximate models, a power model (PM) and a truncated pyramid model (TPM), were parameterized for Urmia Lake and...
Assessment of 2DH and pseudo-3D modelling platforms in a large saline aquatic system: Lake Urmia, Iran, Article Hydrological Processes ; Vol. 28, Issue. 18 , 2014 , pp. 49534970 ; ISSN: 10991085 ; Tofighi, M. A ; Bakhtiari, A ; Sharif University of Technology
The main objective of this paper is to provide comparative quantitative examinations on the capabilities of two-dimensional horizontal and pseudo-three-dimensional (3D) modelling approaches for simulating spatial and temporal variability of the flow and salinity in Lake Urmia, Iran. The water quality in the lake has been an environmentally important subject partly because this shallow hypersaline aquatic ecosystem is considered to be one of the largest natural habitats of a unique multicellular organism, Artemia urmiana. This brine shrimp is the major food source for many of the protected and rare shorebirds that visit the lake. A.urmiana can grow and survive in certain ranges of salinity,...
Article Journal of Great Lakes Research ; Volume 47, Issue 4 , 2021 , Pages 955-969 ; 03801330 (ISSN) ; Parizi, E ; Hosseini, S. M ; Ataie Ashtiani, B ; Sharif University of Technology
International Association of Great Lakes Research 2021
Lake Urmia is the second-largest hypersaline lake in the world. There has been a drastic water level drop of 7.2 m from 1995 to 2016. Beginning in October 2013, the Lake Urmia Restoration Plan (LURP) launched a 10-year program. An increase in water level and a relative improvement in Lake Urmia condition has been observed since 2017. It is an undecided and controversial issue whether the recent positive trend of Lake Urmia has been due to the LURP activities or it is a natural contribution of climate factors variations. To shed some light on this issue, we examine three other lakes, adjacent to the Lake Urmia basin, with similar rainfall variability to investigate their status during the...
Article Journal of Hydrology ; Volume 598 , 2021 ; 00221694 (ISSN) ; Badiezadeh, S ; Pouladi, M ; Yousefi, P ; Farahmand, H ; Kalantari, Z ; Yu, D. J ; Sivapalan, M ; Sharif University of Technology
Elsevier B.V 2021
Lake Urmia in Iran has undergone catastrophic desiccation due to increasing anthropogenic development, especially in the agricultural sector. A paramount national goal is to restore the lake to its former healthy condition, but corresponding water governance and restoration efforts have encountered various, mostly human-related, challenges. We argue here that these challenges stem from lack of awareness and insufficient consideration of the local social conditions and the subtleties of human-water interactions, which we collectively refer to as socio-hydrological barriers. Ignorance of such socio-hydrological barriers can lead to policy efforts that are mismatched with local realities and,...
Mapping surface temperature in a hyper-saline lake and investigating the effect of temperature distribution on the lake evaporation, Article Remote Sensing of Environment ; Volume 136 , 2013 , Pages 374-385 ; 00344257 (ISSN) ; Ahmadalipour, A ; Tajrishy, M ; Sharif University of Technology
Remote sensing is an effective tool for capturing spatial and temporal variations of water surface temperature (WST) in large lakes. The WST of Urmia Lake in northwestern Iran was examined from 2007 to 2010, using MODIS land surface temperature (LST) products. Spatial and temporal (diurnal, monthly, seasonal and inter-annual) variations of Urmia Lake WST were also investigated. Results indicate that the MODIS-derived WSTs are in a good agreement with the in situ data (R2=0.92 and bias=-0.27). Spatial analysis of WST revealed that there are three thermal zones along the lake: the shallow region in barriers of the causeway, islands and the shoreline; the south part; and the deep north parts....
Article China Ocean Engineering ; Volume 30, Issue 5 , 2016 , Pages 811-820 ; 08905487 (ISSN) ; Ataie Ashtiani, B ; Hamidi, S. A ; Sharif University of Technology
With all the improvement in wave and hydrodynamics numerical models, the question rises in our mind that how the accuracy of the forcing functions and their input can affect the results. In this paper, a commonly used numerical third-generation wave model, SWAN is applied to predict waves in Lake Michigan. Wind data are analyzed to determine wind variation frequency over Lake Michigan. Wave predictions uncertainty due to wind local effects are compared during a period where wind has a fairly constant speed and direction over the northern and southern basins. The study shows that despite model calibration in Lake Michigan area, the model deficiency arises from ignoring wind effects in small...
Article 2019 Central Asian DUst Conference, CADUC 2019, 8 April 2019 through 12 April 2019 ; Volume 99 , 2019 ; 25550403 (ISSN) ; Ramezanpoor, R ; Sharif University of Technology
EDP Sciences 2019
Atmospheric aerosols affect the Earth's climate, air quality, and thus human health. This study used the Aerosol Optical Depth (AOD) and the Ångström exponent to cluster different particle types over the Lake Urmia Basin. This classification found desert dust and marine (mixed with continental or local-pollution aerosols) as two main aerosol types over the region, while their sources are not well defined. Although different air masses and wind circulation over the study domain in varied months can help to distinguish aerosol sources, measurements are crucial for a complete evaluation
Article International Journal of Environmental Studies ; Volume 64, Issue 2 , 2007 , Pages 161-169 ; 00207233 (ISSN) ; Nazaridoust, A ; Sharif University of Technology
Lake Urmia is a thalassohaline ecosystem. It is an extremely simple ecological pyramid. This makes it a very sensitive ecosystem. This ecosystem has been facing various threats regarding the amount of water released from the associated basin. To calculate the lake water requirement with an ecological approach, we identified three variables: ecology, water quality, and water quantity indices as environmental indicators. The ecological index represented by Artemia urmiana is considered as an independent variable; while, the water quality index represented by concentration of NaCl, and the water quantity index represented by water elevation are regarded as dependent variables. The salinity...
Simulation of Phosphorus in Urban Lakes and the Impact of Structural and Management Measures on Phosphorus Loading (Case Study: Chitgar Artificial Lake), M.Sc. Thesis Sharif University of Technology ; Agha Mohammad Hossein Tajrishi, Massoud
Chitgar Lake, lake located in the north-west of Tehran City, Iran, is an artificial and recreational lake. The total area and volume of this lake are about 132 hectares and 6.9 million cubic meters, respectively. According to the increased temperature, the lake ecosystem is faced with problems such as augmentation of vermin, frogs and algae in the lake area. Qualitative measurements of 59 well taken samples from March 2013 to June 2014, demonstrate that ratio of total nitrogen to total phosphorus is in the range of 21 to 82 with an average of 42. Consequently, phosphorus is the restricting factor for eutrophication in this lake. In this study, by scrutinizing various scenarios, factors...
Article Water (Switzerland) ; Volume 12, Issue 8 , 2020 ; Moshir Panahi, D ; Mousavi, H ; Kalantari, Z ; Tajrishy, M ; Sharif University of Technology
MDPI AG 2020
Lake Urmia in northwestern Iran is the largest lake in Iran and the second largest saltwater lake in the world. The water level in Lake Urmia has decreased dramatically in recent years, due to drought, climate change, and the overuse of water resources for irrigation. This shrinking of the lake may affect local climate conditions, assuming that the lake itself affects the local climate. In this study, we quantified the lake's impact on the local climate by analyzing hourly time series of data on climate variables (temperature, vapor pressure, relative humidity, evaporation, and dewpoint temperature for all seasons, and local lake/land breezes in summer) for the period 1961-2016. For this, we...
Influence of lakebed sediment deposit on the interaction of hypersaline lake and groundwater: A simplified case of lake Urmia, Iran, Article Journal of Hydrology ; Volume 588 , 2020 ; Ataie Ashtiani, B ; Safaie, A ; Simmons, C. T ; Sharif University of Technology
Elsevier B.V 2020
Lake Urmia, which was once the second-largest saline lake in the world, has been shrinking dramatically. Moreover, Lake Urmia has become supersaturated with total salinity averaging more than 350 g/l. Salt precipitation and dissolved materials brought by inflowing rivers have formed a layer of sediment with low hydraulic conductivity on the lakebed. Considering the flat bathymetry of Lake Urmia, we conducted a series of numerical simulation scenarios to study the groundwater flow pattern in the vicinity of the hypersaline Lake Urmia using COMSOL Multiphysics®. In the first step, we performed the simulations in steady-state conditions. Secondly, we simulated the lake level fall in 10 years at...
Revisiting bathymetry dynamics in Lake Urmia using extensive field data and high-resolution satellite imagery, Article Journal of Hydrology ; Volume 603 , 2021 ; 00221694 (ISSN) ; Bayati, M ; Tajrishy, M ; Chehrenegar, B ; Sharif University of Technology
Elsevier B.V 2021
Bathymetric mapping for an accurate estimation of stored water volume in drying lakes is a key information for an effective monitoring of their recession or restoration status. Extraction of bathymetry in shallow saline lakes using remote sensing techniques has always been challenging due to the complex influences imposed by the physical properties of substrate and the spatial variability of salinity. In this study, we developed a machine learning-based model to quantify the implicit, non-linear relationship between water depth and surface reflectance by leveraging extensive in-situ data and high-resolution satellite imagery. We trained and tested the learning model in the hyper-saline Lake...
M.Sc. Thesis Sharif University of Technology ; Abrishamchi, Ahmad
Lakes, marshes, and wetlands shrinkage and drying up due to natural and human driving forces is today one of the most important concerns in the world. Mahaarloo Salt Lake in southern part of Iran is (18 km far from south eastern of Shiraz ) drying-up and is faced with ecologic and environmental degradation. It recharges from western north by upstream basin of Shiraz and 3 rivers named Khoshk, Chenaarrahdaar, Soltaanabad and also from eastern south by Nazarabad river located in Sarvestan basin (Regional water org. of Fars 1382). In recent years, the shrinkage of Mahaarloo has been exacerbated by mismanagement of water resources, inappropriate land use, ignoring allocation of environmental...
Article Scientia Iranica ; Volume 23, Issue 4 , 2016 , Pages 1627-1632 ; 10263098 (ISSN) ; Abbaspour, M ; Arjmandi, R ; Abedi, Z ; Sharif University of Technology
Sharif University of Technology 2016
The climate change and human development in lake catchments have put these habitats in drying conditions, e.g. Aral Sea in Asia, Lake Chad in Africa, Lake Mead in USA, Lake Urmia in Iran, etc. These ecosystems play an important role in social, ecological, and economic activities. Lake Urmia, recognized as an international wetland in 1973 and located in Iran, which is the second largest hypersaline lake in the world, is in the same state. Lake Urmia biologically and ecologically is one of the most interesting places in the world. This lake is a habitat for various species. The lake's surface has shrunken from 6000 km2 to 900 km2 in 2013. The statistics indicate that the population has...