Dr Omer Yetemen

Dr Omer Yetemen

Lecturer

School of Engineering

Career Summary

Biography

Omer joined the Discipline of Civil Engineering in Jan 2016. He received his PhD in Civil Engineering from the University of Washington, Seattle, USA. Then, he worked as a Postdoctoral Fellow at the Global Institute for Water Security at the University of Saskatchewan, Canada.  His interests are ecohydrology, geomorphology, land-surface modelling and vegetation dynamics. The overarching goal of his research is trying to improve our current understanding about the role of climate on land-surface processes through vegetation dynamics. 


Qualifications

  • Doctor of Philosophy, University of Washington
  • Bachelor of Geological Engineering, Istanbul Technical University, Turkey
  • Master of Science, Istanbul Technical University, Turkey
  • Master of Science, University of Nebraska, USA

Keywords

  • ecohydrology
  • geomorphology
  • landscape evolution modeling
  • vegetation dynamics

Professional Experience

UON Appointment

Title Organisation / Department
Lecturer University of Newcastle
School of Engineering
Australia

Academic appointment

Dates Title Organisation / Department
25/08/2014 - 15/01/2016 Postdoctoral Fellow University of Saskatchewan
Global Institute for Water Security
Canada
15/10/2009 - 15/06/2014 Graduate Research Assistant University of Washington
Department of Civil and Environmental Engineering
United States
14/08/2006 - 30/09/2009 Graduate Research Assistant University of Nebraska
Earth and Atmospheric Sciences
United States

Teaching

Code Course Role Duration
CIVL4330 Hydrology
Faculty of Engineering and Built Environment - The University of Newcastle (Australia)
Instructor 22/02/2016 - 3/06/2016
CIVL4330 Hydrology
Faculty of Engineering and Built Environment - The University of Newcastle (Australia)
Instructor 27/02/2017 - 2/06/2017
CIVL4601 Environmental Engineering Project 2
Faculty of Engineering and Built Environment - The University of Newcastle (Australia)
Instructor 25/07/2016 - 25/11/2016
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Publications

For publications that are currently unpublished or in-press, details are shown in italics.


Journal article (9 outputs)

Year Citation Altmetrics Link
2018 Yeo IY, Lang MW, Lee S, McCarty GW, Sadeghi AM, Yetemen O, Huang C, 'Mapping landscape-level hydrological connectivity of headwater wetlands to downstream waters: A geospatial modeling approach - Part 1', Science of the Total Environment, (2018)

© 2018 Elsevier B.V. Headwater wetlands affect ecosystem integrity of downstream waters; however, many wetlands ¿ particularly geographically isolated wetlands (GIWs) ¿ continue t... [more]

© 2018 Elsevier B.V. Headwater wetlands affect ecosystem integrity of downstream waters; however, many wetlands ¿ particularly geographically isolated wetlands (GIWs) ¿ continue to be at risk. A significant portion of US federal policy is based on the jurisdictional status of wetlands, which is partly determined by the relationship between wetlands and downstream waters, including the cumulative impact of wetlands on those waters. We present a novel multi-phase geospatial modeling method to help elucidate hydrological relationship between GIWs and downstream waters at the landscape scale. The presented approach in this study used inundation maps derived from time series remotely sensed data between 1985 and 2010, weather and hydrological records, and ancillary geospatial data including information from the US Fish and Wildlife Service National Wetlands Inventory (NWI). The study site was a headwater catchment (292 km2) of the Choptank River Basin, located in the Mid-Atlantic region of USA, which contained a large number of Delmarva bays. The results showed inundation extent within GIWs varied, in aggregate, in response to weather variability (r = 0.58; p-value = 0.05), and was well correlated with streamflow (r = 0.81; p-value < 0.01) and base flow (r = 0.57; p-value < 0.1) conditions. The relationship between inundation patterns and stream discharge also varied with NWI hydrologic modifiers. The GIWs with water regime characterized by longer durations of flooding exhibited stronger correlations with stream discharge, but those GIWs with shorter durations of flooding were less correlated with stream discharge. This analysis suggests the mutual reliance (i.e., connection) of wetlands and streams on groundwater. GIWs appeared to function in aggregate, and it is likely that the combined effect of these wetlands significantly influenced the functioning of downstream waters.

DOI 10.1016/j.scitotenv.2018.11.238
Citations Scopus - 1
Co-authors In-Young Yeo
2018 Yeo IY, Lee S, Lang MW, Yetemen O, McCarty GW, Sadeghi AM, Evenson G, 'Mapping landscape-level hydrological connectivity of headwater wetlands to downstream waters: A catchment modeling approach - Part 2', Science of the Total Environment, (2018)

© 2018 Elsevier B.V. In Part 1 of this two-part manuscript series, we presented an effective assessment method for mapping inundation of geographically isolated wetlands (GIWs) an... [more]

© 2018 Elsevier B.V. In Part 1 of this two-part manuscript series, we presented an effective assessment method for mapping inundation of geographically isolated wetlands (GIWs) and quantifying their cumulative landscape-scale hydrological connectivity with downstream waters using time series remotely sensed data (Yeo et al., 2018). This study suggested strong hydrological coupling between GIWs and downstream waters at the seasonal timescale via groundwater. This follow-on paper investigates the hydrological connectivity of GIWs with downstream waters and cumulative watershed-scale hydrological impacts over multiple time scales. Modifications were made to the representation of wetland processes within the Soil and Water Assessment Tool (SWAT). A version of SWAT with improved wetland function, SWAT-WET, was applied to Greensboro Watershed, which is located in the Mid-Atlantic Region of USA, to simulate hydrological processes over 1985¿2015 under two contrasting land use scenarios (i.e., presence and absence of GIWs). Comparative analysis of simulation outputs elucidated how GIWs could influence partitioning of precipitation between evapotranspiration (ET) and terrestrial water storage, and affect water transport mechanisms and routing processes that generate streamflow. Model results showed that GIWs influenced the watershed water budget and stream flow generation processes over the long-term (30 year), inter-annual, and monthly time scales. GIWs in the study watershed increased terrestrial water storage during the wet season, and buffered the dynamics of shallow groundwater during the dry season. The inter-annual modeling analysis illustrated that densely distributed GIWs can exert strong hydrological influence on downstream waters by regulating surface water runoff, while maintaining groundwater recharge and ET under changing (wetter) climate conditions. The study findings highlight the hydrological connectivity of GIWs with downstream waters and the cumulative hydrological influence of GIWs as hydrologic sources to downstream ecosystems through different runoff processes over multiple time scales.

DOI 10.1016/j.scitotenv.2018.11.237
Citations Scopus - 1
Co-authors In-Young Yeo
2018 Saco PM, Moreno-de las heras M, Keesstra S, Baartman J, Yetemen O, Rodriguez J, 'Vegetation and soil degradation in drylands: Non linear feedbacks and early warning signals', Current Opinion in Environmental Science & Health, 5 67-72 (2018) [C1]
DOI 10.1016/j.coesh.2018.06.001
Co-authors Patricia Saco, Jose Rodriguez
2015 Yetemen O, Istanbulluoglu E, Flores-Cervantes JH, Vivoni ER, Bras RL, 'Ecohydrologic role of solar radiation on landscape evolution', WATER RESOURCES RESEARCH, 51 1127-1157 (2015) [C1]
DOI 10.1002/2014WR016169
Citations Scopus - 23Web of Science - 24
2015 Yetemen O, Istanbulluoglu E, Duvall AR, 'Solar radiation as a global driver of hillslope asymmetry: Insights from an ecogeomorphic landscape evolution model', WATER RESOURCES RESEARCH, 51 9843-9861 (2015) [C1]
DOI 10.1002/2015WR017103
Citations Scopus - 10Web of Science - 10
2010 Yetemen O, Istanbulluoglu E, Vivoni ER, 'The implications of geology, soils, and vegetation on landscape morphology: Inferences from semi-arid basins with complex vegetation patterns in Central New Mexico, USA', Geomorphology, 116 246-263 (2010)

This paper examines the relationship between land surface properties (e.g. soil, vegetation, and lithology) and landscape morphology quantified by the catchment descriptors: the s... [more]

This paper examines the relationship between land surface properties (e.g. soil, vegetation, and lithology) and landscape morphology quantified by the catchment descriptors: the slope-area (S-A) relation, curvature-area (C-A) relation, and the cumulative area distribution (CAD), in two semi-arid basins in central New Mexico. The first site is composed of several basins located in today's desert elevations with mesic north-facing and xeric south-facing hillslopes underlain by different lithological formations. The second site is a mountainous basin exhibiting vegetation gradients from shrublands in the lower elevations to grasslands and forests at higher elevations. All three land surface properties were found to have significant influences on the S-A and C- A relations, while the power-law exponents of the CADs for these properties did not show any significant deviations from the narrow range of universal scaling exponents reported in the literature. Among the three different surface properties we investigated, vegetation had the most profound impact on the catchment descriptors. In the S-A diagrams of the aspect-controlled ecosystems, we found steeper slopes in north-facing aspects than south-facing aspects for a given drainage area. In elevation-controlled ecosystems, forested landscapes exhibited the steepest slopes for the range of drainage areas examined, followed by shrublands and grasslands in all soil textures and lithologies. In the C-A diagrams, steeper slopes led to a higher degree of divergence on hillslopes and a higher degree of convergence in the valleys than shallower slopes. The influence of functional types of vegetation detected on observed topography provided some initial understanding of the potential impacts of life on the organization of topography. This finding also emphasizes the critical role of climate in catchment development. We suggest that climatic fluctuations that are capable of replacing vegetation communities could lead to highly amplified hydrological and geomorphic responses.

DOI 10.1016/j.geomorph.2009.11.026
Citations Scopus - 43Web of Science - 44
2009 Yetemen O, Yalcin T, 'Climatic parameters and evaluation of energy consumption of the Afyon geothermal district heating system, Afyon, Turkey', Renewable Energy, 34 706-710 (2009)

Afyon geothermal district heating system (AFJET) provides heating to 4519 residences, covering an area of 513,683 m2. Due to limitations in reinjection capacity, geothermal waters... [more]

Afyon geothermal district heating system (AFJET) provides heating to 4519 residences, covering an area of 513,683 m2. Due to limitations in reinjection capacity, geothermal waters are released to the Akarcay Stream, detrimentally affecting the environment. Optimum heating load of the system was determined for a given ambient conditions with respect to different outdoor temperatures. Usage of AFJET was found to be higher than the optimum consumption rates. Optimizing the usage of geothermal water will decrease operational cost, increase equipment life-span, and reduce environmental pollution.

DOI 10.1016/j.renene.2008.04.020
Citations Scopus - 8Web of Science - 5
2009 Yalcin T, Yetemen O, 'Local warming of groundwaters caused by the urban heat island effect in Istanbul, Turkey', Hydrogeology Journal, 17 1247-1255 (2009)

The urban heat island (UHI) is a result of urbanization, causing local microclimatologic changes such as increase in ambient temperature. Factors causing the UHI effect are anthro... [more]

The urban heat island (UHI) is a result of urbanization, causing local microclimatologic changes such as increase in ambient temperature. Factors causing the UHI effect are anthropogenic energy release, energy absorption by concrete, tarmac structures and traffic, although the main factor is the replacement of vegetation with man-made structures. These factors cause heating of not only local air but also subsurface and groundwater. Observations of groundwater temperatures from the urban, southern part of Istanbul (Turkey) and the rural, northern part of Istanbul revealed that the urban groundwater temperatures were 3.5°C higher than the rural. Urbanization is a direct consequence of improvements in technology and modern life. However, this comes at the cost of an ever-increasing demand for energy. Exploitation of low-enthalpy geothermal energy is an attractive alternative to fossil fuel based energies. From the environmental point of view, clean and cheap energy is the most preferable, with heat pumps being the best choice for recovery purposes. Usage of elevated groundwater temperature in the heat pumps in urban areas increases the efficiency of the heat pump system and yields more thermal energy than that of rural groundwater. This system may be applicable to Istanbul. © Springer-Verlag 2009.

DOI 10.1007/s10040-009-0474-7
Citations Scopus - 14Web of Science - 16
2008 Istanbulluoglu E, Yetemen O, Vivoni ER, Gutiérrez-Jurado HA, Bras RL, 'Eco-geomorphic implications of hillslope aspect: Inferences from analysis of landscape morphology in central New Mexico', Geophysical Research Letters, 35 (2008)

We investigate the influence of hillslope aspect on landscape morphology in central New Mexico, where differences in soils, vegetation, and landforms are observed between mesic no... [more]

We investigate the influence of hillslope aspect on landscape morphology in central New Mexico, where differences in soils, vegetation, and landforms are observed between mesic north-facing and xeric south-facing slopes. Slope-area and curvature-area relations, derived from a Digital Elevation Model (DEM), are used to characterize the opposing hillslope morphologies. In all geologies and elevation ranges studied, topographic data reveal significantly steeper slopes in north-facing aspects, and shallower slopes in south-facing aspects. North-facing slope curvatures are also greater than south-facing curvatures. Using a conceptual slope-area model, we suggest that for a given drainage area, steeper north-facing slopes imply lower soil erodibility. We argue that this interpretation, consistent with recent views of ecosystem control on semiarid erosion rates, shows the influence hillslope aspect on topography and its associated vegetation communities. Observed valley asymmetry in the region reinforces this concept and suggests a long-term legacy of aspect-modulated ecogeomorphic proceses. Copyright 2008 by the American Geophysical Union.

DOI 10.1029/2008GL034477
Citations Scopus - 51Web of Science - 49
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Conference (1 outputs)

Year Citation Altmetrics Link
2017 Yeo I, Lang M, Huang C, Yetemen O, 'Evolution of wetland monitoring from inventory to functional assessment and modelling: a case study from a US catchment', The 22nd International Congress on Modelling and Simulation (MODSIM2017), Hobart, Tasmania, Australia (2017) [E1]
Co-authors In-Young Yeo
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Research Supervision

Number of supervisions

Completed0
Current3

Current Supervision

Commenced Level of Study Research Title Program Supervisor Type
2017 PhD A Global Eco-Hydro-Geomorphic Analysis PhD (Civil Eng), Faculty of Engineering and Built Environment, The University of Newcastle Principal Supervisor
2016 PhD COUPLING A BIOCHEMICAL VEGETATION DYNAMIC MODEL WITH LANDSCAPE EVOLUTION FOR CLIMATE CHANGE IMPACTS ASSESSMENT PhD (Civil Eng), Faculty of Engineering and Built Environment, The University of Newcastle Co-Supervisor
2016 PhD Climate - Soil - Vegetation Interactions: Eco-hydro-geomorphic Inferences from Landscape Evolution Models PhD (Civil Eng), Faculty of Engineering and Built Environment, The University of Newcastle Co-Supervisor
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Research Collaborations

The map is a representation of a researchers co-authorship with collaborators across the globe. The map displays the number of publications against a country, where there is at least one co-author based in that country. Data is sourced from the University of Newcastle research publication management system (NURO) and may not fully represent the authors complete body of work.

Country Count of Publications
United States 8
Australia 2
Canada 2
Turkey 2
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Dr Omer Yetemen

Position

Lecturer
Civil Engineering
School of Engineering
Faculty of Engineering and Built Environment

Contact Details

Email omer.yetemen@newcastle.edu.au
Phone 4921 5452
Fax 4921 6991

Office

Room EA125
Building Engineering A
Location Callaghan Campus
University Drive
Callaghan, NSW 2308
Australia
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