Ankara'da yağış ve su buharının çevresel izotop içeriklerinin zamanla değişiminin incelenmesi

Thesis Type: Postgraduate

Institution Of The Thesis: Hacettepe University, Fen Bilimleri Enstitüsü, Jeoloji Mühendisliği A.B.D., Turkey

Approval Date: 2003

Thesis Language: Turkish


Supervisor: Türker Kurttaş


INVESTIGATION OF TEMPORAL VARIATION IN ENVIRONMENTAL ISOTOPE CONTENTS IN PRECIPITATION AND WATER VAPOUR IN ANKARA Abdullah DİRİCAN Hacettepe University, Department of Geological Engineering, Hydrogeological Engineering Section ABSTRACT in this study one-year record of 82H and 8180 in daily composite samples of water vapour and precipitation, together with relevant hydrometeorological parameters are presented for Ankara. Sampling of precipitation and water vapour was carried out in the Ankara, from January 2001 till December 2001 by means of a standard pluviometer and water vapour sampling system respectively. The relation between the isotopic composition and various synoptic parameters was discussed. Based on "deuterium excess" values, the rain samples separated into three groups. The origin and trajectory of precipitated air masses (for 26 rain event), which effects Ankara in the year 2001, were classified. For each group of air masses an approximate local meteoric water lines and percentage frequencies were calculated by using computed trajectories. In the future it will be possible to construct a regional precipitation network for identification of monthly isotopic composition of precipitation based on trajectory method. Continuous time series of 82H and 8180 in atmospheric water vapour and precipitation at Ankara are presented for the year 2001. A higher correlation coefficient was found between the stable isotopic content of total monthly precipitation and monthly temperature than of daily/event precipitation. Because of partial evaporation, the lover deuterium excess values obtained for precipitation than for water vapour. The higher deuterium excess value of water vapour caused by admixture of water vapour evaporated from bare soil. The obtained data of this study will be used to determine evaporation rate in unsaturated zone and water budget components of lake in central Anatolia region by using 52H and 8180 stable isotopes. Keywords: Stable isotopes, Air masses, Water vapour. Advisor: Türker KURTTAŞ, Hacettepe University, Department of Geological Engineering, Hydrogeological Engineering Section.