This is the website of the Large Scale Hydrology research group of the Institute of Hydraulic Research at the Federal University of Rio Grande do Sul, in Porto Alegre, Brazil. The Large-scale Hydrology research group is part of the Institute of Hydraulic Research within the Federal University of Rio Grande do Sul, consisting of professors, researchers and students from UFRGS Postgraduate Course in Hydrological Resources and Environmental Sanitation, together with associates from other institutions.
The research group aims at improving knowledge on hydrology of large water basins and rivers, emphasizing in South America. Current and future problems in the use and management of water resources, in addition to natural disasters, occur as a result or thousands of miles, reaching continental or global scale, transcending political boundaries between states and countries. The integrated view of these issues requires hydrological analysis at the local, regional, national, continental and global scales. These analyzes seem driven by the increasing availability of information, given by the recent advances in hydrological and hydraulic modeling systems, new remote sensors and better interpretation resources and statistical analysis of large data volumes.
Focus areas are:
Development of hydrological models – We developed the large-scale hydrological model MGB; the large scale water quality model SIAQUA-IPH; and a waterbalance model for analysis of water rights and permits SAD-IPH.
Flood forecasting and general hydrological forecasting – We develop streamflow forecasting techniques using quantitative precipitation forecasts and remote sensing precipitation estimates. We are now developing methods of ensemble flow forecasting.
Analysis of hydrological change – Analysis of the effects of vegetation and land-use change on hydrology of large rivers. Analysis of impacts of climate change and variability; Mitigation of adverse effects of climate variability and extreme weather events such as flood and drought on rivers;
Development of hydrodynamic models of rivers and lakes.
Application of remote sensing data to hydrology – River altimetry; Remote sensing of precipitation and evapotranspiration.
Development of geoprocessing tools applied to hydrology – Deriving useful information from Digital Elevation Models (DEM); Integration between Geographical Information Systems and hydrological models.
This website contains information on research carried out by members of the group, resulting publications and mathematical models developed by our group. Some of the recent activities carried out by this group include:
•Cooperation in Technologies for Hydrological Analysis on a National Scale;
•Study and Water Modeling of Natural Systems with the support of Remote Sensing;
•Hydrosedimentological modeling of large-scale hydrographic basins;
•South America Hydrological Model;
•Estimation of evapotranspiration by remote sensing for the management of water resources in Brazil;
•Remote sensing applied to the modeling of climatic and hydro-meteorological processes;
•Forecast of flows and levels in the Laguna dos Patos watershed.
After all, what is large-scale hydrology?
For us, large-scale hydrology is the study of large watersheds. And large hydrographic basins, in our view, roughly fit the following criteria (not definitive):
– Regions generally larger than 1000 km²;
– Regions where the river propagation processes cannot be neglected, that is, that the travel time of water in the drainage network is long (high concentration time) and that the processes of translation and attenuation of flood waves are relevant in the understanding of the dynamics of the basin;
– Regions where the difference between surface and groundwater dividers can be overlooked;
– Regions where rain and other characteristics such as type and use of soil cannot be considered homogeneous throughout the area, and for this reason the classic hydrology methods are not adequate; – Regions where terrain characterization is difficult to do with purely in-situ measurements, requiring the support of GIS and remote sensing techniques.
In the following image, starting from the upper left corner, in a clockwise direction, the Bãnado La Estrella in Argentina, the Rio Negro and the Rio San Francisco are presented. These photos were taken by the group’s researchers during field work and expeditions.