scholarly journals Performance evaluation and hydrological trend detection of a reservoir under climate change condition

Author(s):  
Rabindranath Sethi ◽  
Brij Kishor Pandey ◽  
Radha Krishan ◽  
Deepak Khare ◽  
P. C. Nayak
2019 ◽  
Author(s):  
Champak Bhakat

In order to decide the optimum time of grazing for camels during hot summer months, 10 growing camel calveswere divided into 2 equal groups. First group was sent for grazing during 10:00 h to 16:00 h daily and second groupallowed for grazing during thermo neutral period. The climatic variables were recorded daily (April 2012 to March2013). The average daily gain and total body weight gain in calves sent for grazing during relatively cool parts ofday (group 2) was significantly higher as compared to group 1 calves sent as per routine farm schedule. Theaverage intake of fodder and water from manger was higher in group 1 calves. The average DMI from manger forgroup 1 calves was higher as compared to group 2 calves. The comparative biometrics of camel calves in differentgrazing management practices revealed that body length, heart girth, height at wither, neck length were significantly(P<0.01) higher in group 2 calves as compared to group 1 calves. After 180 days of experimentation, humpcircumference vertical and hind leg length were significantly (P<0.05) increased in group 2 as compared to group1. Analysis of recorded data of climatic parameters revealed that average maximum temperature was higher duringJune 2012. The values of THI also were higher in monsoon and post monsoon months hence the practice of sendingcamel calves during relatively comfortable part of hot and hot humid months was successful in getting good growth.The relative humidity was significantly higher during morning as compared to evening period for all months. TheTHI was significantly lower during morning as compared to evening hours for all months in different climate forwhole year. Economic analysis reveals that the cost of feed per kg body weight gain was quite less in group 2 ascompared to group 1. So the practice of grazing of camel calves during cool hours of day remain profitable forfarmers by looking at the body weight gain and better body conformation in climate change condition.


2020 ◽  
Vol 163 (3) ◽  
pp. 1329-1351 ◽  
Author(s):  
Anne Gädeke ◽  
Valentina Krysanova ◽  
Aashutosh Aryal ◽  
Jinfeng Chang ◽  
Manolis Grillakis ◽  
...  

AbstractGlobal Water Models (GWMs), which include Global Hydrological, Land Surface, and Dynamic Global Vegetation Models, present valuable tools for quantifying climate change impacts on hydrological processes in the data scarce high latitudes. Here we performed a systematic model performance evaluation in six major Pan-Arctic watersheds for different hydrological indicators (monthly and seasonal discharge, extremes, trends (or lack of), and snow water equivalent (SWE)) via a novel Aggregated Performance Index (API) that is based on commonly used statistical evaluation metrics. The machine learning Boruta feature selection algorithm was used to evaluate the explanatory power of the API attributes. Our results show that the majority of the nine GWMs included in the study exhibit considerable difficulties in realistically representing Pan-Arctic hydrological processes. Average APIdischarge (monthly and seasonal discharge) over nine GWMs is > 50% only in the Kolyma basin (55%), as low as 30% in the Yukon basin and averaged over all watersheds APIdischarge is 43%. WATERGAP2 and MATSIRO present the highest (APIdischarge > 55%) while ORCHIDEE and JULES-W1 the lowest (APIdischarge ≤ 25%) performing GWMs over all watersheds. For the high and low flows, average APIextreme is 35% and 26%, respectively, and over six GWMs APISWE is 57%. The Boruta algorithm suggests that using different observation-based climate data sets does not influence the total score of the APIs in all watersheds. Ultimately, only satisfactory to good performing GWMs that effectively represent cold-region hydrological processes (including snow-related processes, permafrost) should be included in multi-model climate change impact assessments in Pan-Arctic watersheds.


Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2428 ◽  
Author(s):  
Byeong Wook Lee ◽  
Woo-Sun Park

Climate change has resulted in increased intensity and frequency of typhoons and storm surges. Accordingly, attention has been paid to securing the breakwater’s stability to protect the safety of the port. Herein, hydraulic model experiments were conducted to evaluate the hydraulic performance of a vertical breakwater having a rear parapet. For comparison, cases in which the parapet was placed on the seaside, the harborside, and at the center of the breakwater were considered. Regular waves were used for convenient performance analysis. Five wave gauges and nine pressure transducers were installed to secure physical data for hydraulic performance evaluation. Results showed that a rear parapet can reduce the maximum wave force acting on the breakwater. Even though impulsive pressure was generated, it did not affect the stability of the breakwater owing to the phase difference between the maximum wave pressures acting on the caisson and parapet. By decreasing the maximum wave force, the required self-weight that satisfies the safety factor of 1.2 was reduced by up to 82.7%; the maximum bearing pressure was reduced by up to 47.6% compared with that of the parapet located on the seaside. Thus, the rear parapet was found to be more suitable for actual applications.


2021 ◽  
Vol 21 (62) ◽  
pp. 281-298
Author(s):  
zahra sadat Jalali Chimeh ◽  
Amir Gandomkar ◽  
Morteza Khodagholi ◽  
Hossein Battoli ◽  
◽  
...  

2018 ◽  
Vol 4 (10) ◽  
pp. eaau0049 ◽  
Author(s):  
Cheng-Zhi Zou ◽  
Mitchell D. Goldberg ◽  
Xianjun Hao

Observations from the satellite microwave sounders play a vital role in measuring the long-term temperature trends for climate change monitoring. Changes in diurnal sampling over time and calibration drift have been the main sources of uncertainties in the satellite-measured temperature trends. We examine observations from the first of a series of U.S. new generation of microwave sounder, the Advanced Technology Microwave Sounder (ATMS), which has been flying onboard the National Oceanic and Atmospheric Administration (NOAA)/NASA Suomi National Polar-orbiting Partnership (SNPP) environmental satellite since late 2011. The SNPP satellite has a stable afternoon orbit that has close to the same local observation time as NASA’s Aqua satellite that has been carrying the heritage microwave sounder, the Advanced Microwave Sounding Unit-A (AMSU-A), from 2002 until the present. The similar overpass timing naturally removes most of their diurnal differences. In addition, direct comparison of temperature anomalies between the two instruments shows little or no relative calibration drift for most channels. Our results suggest that both SNPP/ATMS and Aqua/AMSU-A instruments have achieved absolute stability in the measured atmospheric temperatures within 0.04 K per decade. This uncertainty is small enough to allow reliable detection of the temperature climate trends and help to resolve debate on relevant issues. We also analyze AMSU-A observations onboard the European MetOp-A satellite that has a stable morning orbit 8 hours apart from the SNPP overpass time. Their comparison reveals large asymmetric trends between day and night in the lower- and mid-tropospheric temperatures over land. This information could help to improve climate data records for temperature trend detection with improved accuracy. The SNPP satellite will be followed by four NOAA operational Joint Polar Satellite System (JPSS) satellites, providing accurate and stable measurement for decades to come. The primary mission of JPSS is for weather forecasting. Now, with the added feature of stable orbits, JPSS observations can also be used to monitor changes in climate with much lower uncertainty than the previous generation of NOAA operational satellites.


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