“How will the flow rate change in the next 30 years according to climate scenarios? Are we likely to expect a reduction or an increase?”
These questions may seem speculative with no practical use. In fact, they are posing a crucial issue, especially for many professionals that need to design a new or to revamp an existing plant.
The temperature increase is likely to raise the snow line and anticipate the time of melting. At the same time, evapo-transpiration should increase in summer, with consequent lower water availability.
However, all these drivers have non linear effects and need to be thoroughly analyzed according to the local configuration of the plant, size of the catchment and climate scenarios.
Current methods generally use a statistical approach, purely based on historical data, to derive the duration curve of water discharge and the likelihood of extreme events to design the plant.
However, global warming has changed the water regimes in most rivers and watercourses, making historical data obsolete and leaving lots of uncertainties with respect to future precipitation patterns and snow persistence. The results are:
Waterjade has developed sophisticated models, including physically-based hydrological models and machine-learning algorithms, capable to downscale the results of the Global Meteorological Models according to local morphology and historical climate.
In this way it is possible to account for the Representative Concentration Pathways (RCP) of CO2 concentration in the calculations, providing, with a probabilistic approach, the possible water scenarios in the target catchment.