Intercomparison of grace-based groundwater level change and in-situ measurements over Central Anatolia basins, Turkey

Download

index.pdf

Date

2019

Author

Karasu, İpek Gül

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

128
views

91
downloads

The purpose of this study is to validate the satellite- (GRACE) and hydrological model- (GLDAS) based groundwater storage (GWS) change information using in-situ groundwater level observations and investigate the accuracy of Gravity Recovery and Climate Experiment (GRACE) retrievals over Central Anatolia. In this study, GRACE-derived GWS changes from January 2003 to December 2015 are compared with in-situ groundwater level observations from five basins comprising Central Anatolia Basin. The basin areas range between 7,605 km2 and 233,929 km2 which are relatively small according to the footprint of GRACE. It is expected that as the basin area increases the accuracy of GRACE-based GWS variations increase. Also, GRACE is skillful to monitor the large mass changes. The highest correlation between GRACE-based GWS and in-situ observations are found between 0.48 and 0.66 and widely ascribed to the seasonal component. Although Akarçay Basin has the lowest surface area, it has a correlation value about 0.53 which is higher than the correlation value of Central Anatolia Basin (r ≈ 0.45). Especially, in Konya Closed Basin, where groundwater levels are significantly decreasing, the correlation coefficient becomes 0.44. This implies that Global Land Data Assimilation System (GLDAS) estimates and GRACE signals do not represent the ground conditions precisely. Despite these results, GRACE-derived terrestrial water storage variations agreed well with the droughts occurred over Turkey in between 2007-2009 and 2014.

Subject Keywords

Groundwater tracers., Central Anatolia, GLDAS, GRACE, Groundwater, Terrestrial Water Storage.

URI

http://etd.lib.metu.edu.tr/upload/12623984/index.pdf
https://hdl.handle.net/11511/44064

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Assessment of Dewatering Requirements and their Anticipated Effects on Groundwater Resources: A Case Study from the Caldag Nickel Mine, Western Turkey Peksezer-Sayit, Ayse; Cankara-Kadioglu, Cigdem; Yazıcıgil, Hasan (2015-06-01) Dewatering requirements of three open pits located in western Turkey and the impact of dewatering on groundwater resources were evaluated using a three-dimensional numerical groundwater flow model. The groundwater was modeled using MODFLOW software and the dewatering was simulated using the MODFLOW Drain Package. The drain cell configurations were determined by pit boundaries; invert elevations of drains corresponded to the bench elevations in the mining schedule, which varied dynamically among the three pi...
Superensembles of raw and bias-adjusted regional climate models for Mediterranean region, Turkey Mesta, Buket; Kentel Erdoğan, Elçin (2021-09-01) For regional-scale studies on climate change and relevant impact assessment, the projections of regional climate models (RCMs) are used due to their advantage of high resolution and better representation of the local climate relative to the global climate models. However, direct use of RCM outputs is prone to uncertainties and biases that may significantly diminish the accuracy of results. EURO-COordinated Regional Downscaling EXperiment (CORDEX) initiative that is a part of the global Coordinated Regional ...
Time-space fractional governing equations of transient groundwater flow in confined aquifers: Numerical investigation Tu, Tongbi; Ercan, Ali; Kavvas, M. Levent (2018-05-01) In order to model non-Fickian transport behaviour in groundwater aquifers, various forms of the time-space fractional advection-dispersion equation have been developed and used by several researchers in the last decade. The solute transport in groundwater aquifers in fractional time-space takes place by means of an underlying groundwater flow field. However, the governing equations for such groundwater flow in fractional time-space are yet to be developed in a comprehensive framework. In this study, a finit...
Radiative-convective model for one-dimensional longwave clear sky atmosphere Aydın, Güzide; Selçuk, Nevin; Department of Chemical Engineering (2008) Climate models are the primary tools used for understanding past climate variations and for future projections. The atmospheric radiation is the key component of these models. Accurate modeling of atmosphere necessitates reliable evaluation of the medium radiative properties and accurate solution of the radiative transfer equation in conjunction with the time-dependent multi-dimensional governing equations of atmospheric models. Due to difficulty in solving the equations of atmospheric and radiation models ...
Probabilistic seismic hazard assessment of Eastern Marmara Region Gülerce, Zeynep (Springer Science and Business Media LLC, 2013-10-01) The objective of this study is to evaluate the seismic hazard in Eastern Marmara Region using an improved probabilistic seismic hazard assessment methodology. Two significant improvements over the previous seismic hazard assessment practices are accomplished in this study: advanced seismic source characterization models in terms of source geometry and recurrence relationships are developed, and improved global ground motion models (NGA-W1 models) are employed to represent the ground motion variability. Plan...

Citation Formats

İ. G. Karasu, “Intercomparison of grace-based groundwater level change and in-situ measurements over Central Anatolia basins, Turkey,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Civil Engineering., Middle East Technical University, 2019.