Geoscience Reference
In-Depth Information
Chapter 7
Geographical Information and
Climatology for Hydrology
7.1. Hydrological problems of today's society
Throughout history different societies have had to deal with problems associated
with water, by either protecting themselves from it or by trying to benefit from its
advantages. Ancient Chinese, Egyptian, and Indian societies had to carry out major
hydraulic work in order to protect themselves from floods. The work that these
societies carried out also enabled them to have access to water as well as being able
to provide water for their herds and crops. The Romans left traces of their vast
knowledge as far as the world of hydraulics is concerned and evidence of this can be
seen by visiting their ancient sites. It is clear that throughout the course of history
there have been different developments in the field of hydraulics. Unlike today,
however, the hydrologists of the past most certainly worked on a trial and error, or
observation basis, and there was certainly no research carried out before a new
development was created (for example, nilometers were used to measure the water
levels of the river Nile in high Egypt several centuries before the birth of Jesus
Christ). However, empiricism and common sense were not always used [HUB 84].
It was not until the modern era and the 20
th
century, in particular, when proper
modern rules stemming from the worlds of physics (hydraulics) and statistics
(hydrology) were used. The term hydraulics may be well known, but the term
“hydrology” is not so well understood. Hydrology is the study of the Earth's water
cycle. The term surface hydrology is used for the superficial part of the water cycle.
For the purpose of this study it is surface hydrology that we are interested in. The
aim of hydrology is to examine the quantity of water flowing on the Earth's surface.
If this quantity of water is known, the field of hydraulics can be used to work out
water levels, and the velocity relative to the environment in which the water is found
[GOU 05].
