ANALYTICAL STUDY ON DIURNAL VARIATION OF SUMMER RIVER TEMPERATURE

Abstract

 Studies on river water temperature have often focused on time scales longer than daily mean, and little is known about daily changes. A two-dimensional heat balance model is developed to investigate daily changes in water temperature in rivers for summer. In a regulated section, water temperature is mainly controlled by solar radiation and advection. Diurnal changes become more apparent along the river flow because of the influence of solar radiation. It reaches the maximum temperature later by a half of the time required for advection. Deep pools prevent downstream water temperature from rising.