Combined effects of pumped-storage operation and climate change on thermal structure and water quality     

Kobler  Ulrike Gabriele  Wüest  Alfred  Schmid  Martin 《Climatic change》2019,152(3-4):413-429

Climatic Change - The assessment of ecological impacts of pumped-storage (PS) hydropower plants on the two connected water bodies is usually based on present climatic conditions. However,...  相似文献   

Ensemble modelling of ice cover for a reservoir affected by pumped‐storage operation and climate change     

Ulrike Gabriele Kobler  Martin Schmid 《水文研究》2019,33(20):2676-2690

Ensemble modelling was used to assess the robustness of projected impacts of pumped‐storage (PS) operation and climate change on reservoir ice cover. To this end, three one‐dimensional and a two‐dimensional laterally averaged hydrodynamic model were set up. For the latter, the strength of the impacts with increasing distance from the dam was also investigated. Climate change effects were simulated by forcing the models with 150 years of synthetic meteorological time series created with a weather generator based on available air temperature scenarios for Switzerland. Future climate by the end of the 21^st century was projected to shorten the ice‐covered period by ~2 months and decrease ice thicknesses by ~13 cm. Under current climate conditions, the ice cover would already be affected by extended PS operation. For example, the average probability of ice coverage on a specific day was projected to decrease by ~13% for current climate and could further be reduced from ~45% to ~10% for future climate. Overall, the results of all models were consistent. Although the number of winters without ice cover was projected to increase for all one‐dimensional models, studying individual segments of the two‐dimensional model showed that the impact was pronounced for segments close to the PS intake/outlet. In summary, the reservoir's ice cover is expected to partially vanish with higher probability of open water conditions closer to the PS intake/outlet.  相似文献   

A new tunable filter with a very narrow pass-band     

J. V. Ramsay  H. Kobler  E. G. V. Mugridge 《Solar physics》1970,12(3):492-501

A new tunable optical filter incorporated in a solar magnetograph consists of an interference filter followed by three automatically controlled Fabry-Pérot interferometers. It has a spectral resolving power of 10⁵, an angular resolution of 5″ arc and a field angle of 30′ arc for this spectral resolving power. By using auxiliary optics the angular resolution of the object may be improved at the expense of the angular field. Thus $$\frac{{angular field}}{{angular resolution}} = 6 are \min (are \sec )^{ - 1} $$ . It is operational over the range 400–650 nm and may be tuned through ± 0.2 nm about the selected transmission band.  相似文献