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OS5b Governing water towards sustainability

abstract 86

ON THE NECESSITY OF RECONSIDERATION OF THE WATER BALANCE EQUATION COMPONENTS.

Author(s): no
Author(s): Iofin K. Zinoviy
Zinoviy Iofin associated professor, Teacher of Hydrology in Vologda State Technical University, Vologda, Russia. Investigates the problems of water resources, water balance and statistical methods of hydrology for 35 years already. Works on the submitte

Keyword(s): water balance equation, water balance equation error, evaporation, runoff, inriltration,absorbation, Global Water Balance, Water Resources, new linear and correlative model of the water balan

Article:

Poster:

Session: OS5b Governing water towards sustainability

Abstracttopic: Regional sector
ON THE NECESSITY OF RECONSIDERATION OF THE WATER BALANCE

EQUATION COMPONENTS.
IOFFIN Z.K.
Vologda State Technical University,
Vologda,

Russia
The structure of the water balance equation that is used for a long time in which precipitation is spent on

evaporation, runoff and closure error is, in our opinion, imperfect. Such a kind of the equation doesn't give even an

opportunity to determine the infiltration precipitation losses, not to mention such water balance elements as

absorption, runoff and precipitation at different stages of water formation and runoff. That supposes essential errors

at determining of any of the equation components. It is quite clear that the already traditional infiltration value

determination on the basis of the long-term observations over the underground waters level, is used only at the

experimental river basins. The mass usage of the traditional infiltration determination method is quite ineffective and

labor-consuming.
In the year 1974 in the framework of the International hydrological decade State Hydrology

Institute (St. Petersburg) published the monograph "Global Water Balance and Water Resources of the Earth".

Unfortunately, the water balance equation used in this monograph, also consisted of the same components, that is,

precipitation, runoff and evaporation. Since there are underground water reservoirs and their infiltration supply, the

infiltration as a component of the water balance equation was used in this monograph indirectly in calculations of

evaporation or runoff. It depended on the hydrological study of the region and availability of the survey data. In case

there were data on precipitations and evaporation and absence of the runoff survey, then the water balance

infiltration equation was indirectly included into the runoff, accordingly increasing it. This means that the water

resources calculations were made with a certain error. If on the contrary the investigators had survey data on the

runoff and precipitations, then the evaporation was increased by the infiltration value. In any case the water balance

is distorted and this means that the mentioned monograph content requires certain corrections.
We suggest a new

linear and correlative model of the water balance equation that could serve the base for reconsideration of the water

balance components equation introduced in the earlier mentioned monograph. Our model lets us on the basis of the

survey data on precipitations and river runoff define analytically not only the infiltration value but that of the

evapotranspiration and evaporation from the water surface, absorption, runoff losses at the drop of each flood,

precipitations losses at the surface slowing up at the water basin.
The Linear and correlative equation model is

checked on materials of the survey data of the rivers of Cuba and Russia and shows a good correlation of the

calculated and real water balance equation components.

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ON THE NECESSITY OF RECONSIDERATION OF THE WATER BALANCE EQUATION COMPONENTS.