Wyniki wyszukiwania - BazTech

1

Hydrological Modeling and Impact of Climate Change on Water Resources in the Ziz Valley, Central High Atlas, Morocco

El Ouali Anas, Dichane Zouhir, Roubil Allal, El Ouardi Hmidou, El Hmaidi Abdellah, Lahrach Abderrahim

Ecological Engineering & Environmental Technology

|

2023

|

Vol. 24, iss. 6

192--210

EN

The Upper Ziz basin located in the southeast of Morocco, has a total area of 4,351 km2. The surface water feeds El Hassan Addakhil dam, which insures water supply for the downstream cities of Errachidia, Rissani, Erfoud and others along the Ziz valley. This study aimed to evaluate the availability of water resources in this basin known by its arid climate and strong climatic changes. Several global hydrological models at different times were used to simulate the discharge at the outlet. The Statistical Downscaling Model (SDSM) method has been used to reduce the average rainfall and the temperature to predict future climate change related to various Representative Concentration Pathway (RCP) scenarios such as RCP 4.5 and RCP 8.5. The results of the hydrologic models are available, with an NSE of 0.8 for the monthly model during calibration and 0.77 at validation. Future precipitation shows an increasing trend in both scenarios. As for future mean temperature, it will recognize great seasonal variability, such as warming winter and spring and cooling summer and autumn. As a result, simulated future discharge will decrease by 26% under RCP 4.5 and by 24% under RCP 8.5 in the near future.

2

Calibration of conceptual rainfall-runoff models by selected differential evolution and particle swarm optimization variants

Napiorkowski Jaroslaw J., Piotrowski Adam P., Karamuz Emilia, Senbeta Tesfaye B.

Acta Geophysica

|

2023

|

Vol. 71, no. 5

2325--2338

EN

The performance of conceptual catchment runoff models may highly depend on the specific choice of calibration methods made by the user. Particle Swarm Optimization (PSO) and Differential Evolution (DE) are two well-known families of Evolutionary Algorithms that are widely used for calibration of hydrological and environmental models. In the present paper, five DE and five PSO optimization algorithms are compared regarding calibration of two conceptual models, namely the Swedish HBV model (Hydrologiska Byrans Vattenavdelning model) and the French GR4J model (modèle du Génie Rural à 4 paramètres Journalier) of the Kamienna catchment runoff. This catchment is located in the middle part of Poland. The main goal of the study was to find out whether DE or PSO algorithms would be better suited for calibration of conceptual rainfall-runoff models. In general, four out of five DE algorithms perform better than four out of five PSO methods, at least for the calibration data. However, one DE algorithm constantly performs very poorly, while one PSO algorithm is among the best optimizers. Large differences are observed between results obtained for calibration and validation data sets. Differences between optimization algorithms are lower for the GR4J than for the HBV model, probably because GR4J has fewer parameters to optimize than HBV.

3

Understanding changes and trends in projected hydroclimatic indices in selected Norwegian and Polish catchments

Meresa H. K., Romanowicz R., Napiórkowski J.

Acta Geophysica

|

2017

|

Vol. 65, no. 4

829--848

EN

The aim of the study is to investigate trends in selected hydroclimatic indices using novel and conventional tools, for future climate projections in the twenty-first century. Selected quasi-natural Norwegian and Polish catchments are used as a case study. The projected flows are provided by GR4J rainfall-runoff conceptual model, coupled with an ensemble of climate model projections from EURO-CORDEX initiative. The trends are analysed using conventional Mann–Kendall and modified Mann–Kendall statistical approaches, a time–frequency approach based on discrete wavelet transform (DWT) and the dynamic harmonic regression (DHR) method. Of all methods applied the DHR gives the most conservative trend estimates. Trends depend on the specific hydroclimatic character and flow regime of the catchment. The results confirmed that in catchments with a rainfall-driven flood regime, an increase in the amount of precipitation is followed by increased flows, with strong seasonal changes, whereas, in catchments with a snow-driven flood regime, despite an increase of mean annual flow, decrease in annual maximum flow is observed. Generally, positive trend is the most dominant in all catchments studied and the methods were consistent in detection of trend except in seasonal trend test.