Ivan Muzik

Bio: Ivan Muzik is an academic researcher. The author has contributed to research in topics: Global warming & Climate change. The author has an hindex of 2, co-authored 2 publications receiving 39 citations.

Sensitivity of Hydrologic Systems to Climate Change

Abstract: If climate change occurs, it could seriously impact water resources in Canada. In this paper I examine the change in flood probabilities in a study watershed in central Alberta in response to increases resulting from global warming in the mean and standard deviations of rainfall depths of storms of various durations. A 25% increase in the mean and a 50% increase in the standard deviation of storm rainfalls were selected based on the assumption that climates typical of southern Alberta, Montana and Colorado would extend northward to central Alberta. Lumped and semi-distributed modelling of the study watershed was used in a Monte Carlo simulation of floods resulting from the new climatic scenario. Simulation results show that modest increases in storm rainfall could result in large changes in flood magnitudes. Consequences of such flow increases on the capacity of a small dam spillway are illustrated.

Sensitivity of Hydrologic Systems to Climate Change

Abstract: Scientific evidence about global climate change and its consequences began to accumulate during the 1980s. In 1988, the United Nations Environment Programme and the World Meteorological Organization jointly established the Intergovernmental Panel on Climate Change (IPCC). The IPCC concluded in its Second Assessment Report (1996) that Earth has already warmed about 0.6 ˚C over the last century, and projected further increases of 1 to 3.5 ˚C by the year 2100. This projection is based on simulation of atmospheric circulation, the energy exchanges, and other important land/ocean/atmosphere interactions by General Circulation Models (GCMs). These models project climate (10-year or longer averages of weather conditions) over several decades, and give only large-scale predictions because grid spacing in most GCMs is between 2 and 5 degrees of longitude or latitude (about 150 to 360 km). Prediction on small time and space scale, needed for design and planning, are not possible at present. However, results from GCMs simulations suggest that the present mid-latitude rain belt would shift northward; snowmelt and spring runoff would occur earlier than at present; evapotranspiration would be greater; the greatest increases in temperatures will occur in the high latitudes, in winter, and over land; extreme weather events (droughts, storms, floods, ice jams, etc.) will be more frequent and more severe. Climate and hydrologic changes may result in important ecological and socioeconomic consequences. The impacts will vary from beneficial to catastrophic depending upon the magnitude and rate of change, the sensitivity of watersheds and ecosystems to change and the ability of natural or man-made systems to adapt to or mitigate that change.

Climate Change Impact on Reservoir Performance Indexes in Agricultural Water Supply

Abstract: This paper addresses the impact of climate change on the volume of inflow to a reservoir and the volume of downstream water demand by considering three climate change scenarios in an East Azerbaijan river basin. The HadCM3 model was used to estimate possible scenarios of temperature and rainfall for the period 2026–2039 under an emission scenario (A2). A hydrological model (IHACRES) was first calibrated for the basin; and then, a monthly time series of future temperatures and rainfall were entered into IHACRES. In addition, a 14-year time series of monthly runoff was simulated for 2026–2039. Modeling results indicated that the average long-term annual runoff volume decreased by 0.7% relative to the base period (1987–2000). However, by assuming a nonchanging cultivation area, the average long-term annual water demand volume for crops increased by 16%. Both simulation and optimization models of reservoir operation were used. The simulation of reservoir performance in the delivery of water demand wa...

Adaptive Reservoir Operation Rules Under Climatic Change

Abstract: Increases in greenhouse gases caused by human activities have raised global temperature. Global warming affects water resources systems and the hydrologic cycle and may impact the performance of water resource systems. Water resources managers face challenges balancing conflicting goals in reservoir operation given the uncertainties introduced by climatic change. The HadCM3 climate model is used in this paper to estimate temperature and precipitation for early (2025–2039), middle (2055–2069) and late (2085–2099) periods of the 21st century under the A2 greenhouse gases emission scenario. The estimated temperature and precipitation from the climate model are input to a calibrated hydrologic model (IHACRES) to simulate inflow in a river basin draining to the Karoon-4 reservoir in Iran. A meta-heuristic multi-objective optimization algorithm (NSGA-II) is used in conjunction to predicted hydrologic variables to optimize dynamic operation rules in the Karoon-4 reservoir. The Karoon4 reservoir is operated non-adaptively and adaptively under climatic change. Our results show that adaptive reservoir management increases the reliability and reduces the vulnerability associated with hydropower generation in early, middle, and late simulation periods of the 21st century. These findings establish the importance of factoring in climatic change and considering adaptive strategies in future reservoir operations.

Streamflow Response to Climate Change in the Brahmani River Basin, India

Abstract: Climate change can significantly affect the water resources availability by resulting changes in hydrological cycle. Hydrologic models are usually used to predict the impacts of landuse and climate changes and to evaluate the management strategies. In this study, impacts of climate change on streamflow of the Brahmani River basin were assessed using Precipitation Runoff Modeling System (PRMS) run under the platform of Modular Modeling System (MMS). The plausible hypothetical scenarios of rainfall and temperature changes were used to assess the sensitivity of streamflow to changed climatic condition. The PRMS model was calibrated and validated for the study area. Model performance was evaluated by using joint plots of daily and monthly observed and simulated runoff hydrographs and different statistical indicators. Daily observed and simulated hydrographs showed a reasonable agreement for calibration as well as validation periods. The modeling efficiency (E) varied in the range of 0.69 to 0.93 and 0.85 to 0.95 for the calibration and validation periods, respectively. Simulation studies with temperature rise of 2 and 4°C indicated 6 and 11% decrease in annual streamflow, respectively. However, there is about 62% increase in annual streamflow under the combined effect of 4°C temperature rise and 30% rainfall increase (T4P30). The results of the scenario analysis showed that the basin is more sensitive to changes in rainfall as compared to changes in temperature.