This book is a revised and slightly expanded version of my book Hydrology, first published in 1974, and then revised in 1995. lî is intended as a texîbook for undergraduate Civil Engineering students taking the Hydrology course in English.
Hydrology has gained a great significance in recent decades with the expansion of the water resources development studies that are an important component of mans efforts in controlling the environment. Although information abouî the water on the earth is being colîected for several centuries, only recently this information is transformed into a Science and put into use in enginee\'ring studies. Hydrology, as a Science that deals with the distribution, motion and properties of the water on the earth, plays an important part in these studies. Hydrologic studies are given an impetus by the rapid growth of the population, agrieulture and industry.
In the book, hydrologic events are analyzed by a system approach, following various components of the hydrologic cycle. It is attempted to introduce the student to the recent developmenîs in hydrologic measurements, and the applications of the methods\' of the system analysis and statistics. A balance is tried to be achieved between various deterministic and probabilistic approaches so that the student can have an idea about the possible methods of treatment of hydrologic problems. Solved problems are added at the end of each chapter to illustrate the use of the methods described in the text. An extensive list of references is given at the end of the book.
I would like to thank to Sevgi Öğün for her careful work in preparing the text on the Computer, and to the owners and staff of Birsen Kitabevi for their cooperation. I extend my thanks to Prof. Dr. Beyhan Oğuz who thoroughly reviewed the manuscript.