scholarly journals Development of Threshold Levels and a Climate-Sensitivity Model of the Hydrological Regime of the High-Altitude Catchment of the Western Himalayas, Pakistan

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1454 ◽  
Author(s):  
Saifullah ◽  
Liu ◽  
Tahir ◽  
Zaman ◽  
Ahmad ◽  
...  

Water shortages in Pakistan are among the most severe in the world, and its water resources are decreasing significantly due to the prevailing hydro-meteorological conditions. We assessed variations in meteorological and hydrological variables using innovative trend analysis (ITA) and traditional trend analysis methods at a practical significance level, which is also of practical interest. We developed threshold levels of hydrological variables and developed a non-parametric climate-sensitivity model of the high-altitude catchment of the western Himalayas. The runoff of Zone I decreased, while the temperature increased and the precipitation increased significantly. In Zone II, the runoff and temperature increased but the precipitation decreased. A two-dimensional visualization of the Pardé coefficient showed extreme drought events, and indicated greater sensitivity of the hydrological regime to temperature than to precipitation. The threshold levels of runoff for Zones I and II were 320 and 363 mm using the Q80 fixed method, while the mean runoff amounts were estimated to be 79.95 and 55.61 mm, respectively. The transient threshold levels varied by month, and the duration of droughts in Zones I and II ranged from 26.39 to 78.98 days. The sensitivity of the hydrological regime was estimated based on a modified climate-elasticity model (εp = 0.11–0.23, εt = −0.04–2.39) for Zones I and II, respectively. These results highlight the sensitivity of the hydrological regime to temperature, which influences the melting process. However, it is important to establish thresholds for hydrological variables and understand the climate sensitivity of the hydrological regime of the entire basin, so that policy makers and water managers can make sustainable water-resource-management decisions for this region.

2008 ◽  
Vol 39 (2) ◽  
pp. 133-141 ◽  
Author(s):  
Maris Klavins ◽  
Valery Rodinov

The study of changes in river discharge is important for regional climate variability characterization and for development of an efficient water resource management system. The hydrological regime of rivers and their long-term changes in Latvia were investigated. Four major types of river hydrological regimes, which depend on climatic and physicogeographic factors, were characterized. These factors are linked to the changes observed in river discharge. Periodic oscillations of discharge, and low- and high-water flow years are common for the major rivers in Latvia. A main frequency of river discharge regime changes of about 20 and 13 years was estimated for the studied rivers. A significant impact of climate variability on the river discharge regime has been found.


The Holocene ◽  
2020 ◽  
Vol 30 (5) ◽  
pp. 733-743 ◽  
Author(s):  
Rayees Ahmad Shah ◽  
Hema Achyuthan ◽  
Aasif Mohmad Lone ◽  
Sanjeev Kumar ◽  
Pankaj Kumar ◽  
...  

We present a comprehensive record of Holocene (11,590–628 cal. yr BP) climate and hydrographic changes around the Wular Lake located in Kashmir Valley, India. Based on the multi-proxy investigations, we have identified three phases of wet climate conditions that prevailed from the commencement of the Holocene Epoch – 9000 cal. yr BP, 8100–6650 cal. yr BP and 6350–5000 cal. yr BP, whereas periods of dry climate were observed during 9000–8100 cal. yr BP, 6650–6350 cal. yr BP and ~5000 to 4000 cal. yr BP. The results also suggested that the lake widened and deepened significantly around 6350–5000 cal. yr BP. The results indicated desiccation and the exposure of the lake margin around 5000–4500 cal. yr BP. The sedimentation rate since 4500–628 cal. yr BP was quite low for detailed paleoclimate interpretations. Oscillations in lake extension and deepening appear to be due to changing intensity of westerly moisture in the region, and we correlate several of the low lake-level phases to the Bond events caused by North Atlantic ice rafting events.


Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1782 ◽  
Author(s):  
Maochuan Hu ◽  
Takahiro Sayama ◽  
Sophal TRY ◽  
Kaoru Takara ◽  
Kenji Tanaka

Understanding long-term trends in hydrological and climatic variables is of high significance for sustainable water resource management. This study focuses on the annual and seasonal trends in precipitation, temperature, potential evapotranspiration, and river discharge over the Kamo River basin from the hydrological years 1962 to 2017. Homogeneity was examined by Levene’s test. The Mann–Kendall and a modified Mann–Kendall test as well as Sen’s slope estimator were used to analyze significant trends (p < 0.05) in a time series with and without serial correlation and their magnitudes. The results indicate that potential evapotranspiration calculated by the Penman–Monteith equation was highly related to temperature, and significantly increased in the annual and summer series. Annual river discharge significantly decreased by 0.09 m3/s. No significant trend was found at the seasonal scale. Annual, autumn, and winter precipitation at Kumogahata station significantly increased, while no significant trend was found at Kyoto station. Precipitation was least affected by the modified Mann–Kendall test. Other variables were relatively highly autocorrelated. The modified Mann–Kendall test with a full autocorrelation structure improved the accuracy of trend analysis. Furthermore, this study provides information for decision makers to take proactive measures for sustainable water management.


1970 ◽  
Vol 8 (3) ◽  
pp. 52-57 ◽  
Author(s):  
Mukunda M Gogoi ◽  
Jai Prakash Chaubey ◽  
V Sreekanth ◽  
Sobhan Kumar Kompalli ◽  
S Suresh Babu ◽  
...  

Continuous measurements of spectral aerosol optical depths (AOD) were made over a very high altitude aerosol observatory at Hanle (32.76°N, 78.95°E, 4520 m amsl), during the summer and autumn of 2009 and 2010, by using a 10-channel multi-wavelength radiometer (MWR). The results depicted very low values of AOD (with a mean for the measurement period as ~ 0.071 ± 0.003 at 500 nm), but with a spectral dependence that changed with the months from ~ 0.8 to 1.3, with a mean value of ~ 1.01 ± 0.06. The AODs though were in general comparable to those seen over pristine Antarctic environments, are quite significant when we consider the altitude of the station. The details are presented. DOI: http://dx.doi.org/10.3126/jie.v8i3.5931 JIE 2011; 8(3): 52-57


Author(s):  
Igor Leščešen ◽  
Dragan Milošević ◽  
Rastislav Stojsavljević

For the trend analysis of the annual, seasonal and monthly precipitation linear regression and Mann-Kendall (MK) tests at the 5% significance level were applied. In this study, precipitation data from two stations in Serbia for the 1949-2019 period were used. Results indicate that increasing trends of precipitation for the selected station can be observed but these trends were not statistically significant according to MK test. Then again, MK test has shown that only on Palić station during autumn precipitations have statistically significant increase during the observed period with a p value of 0.0441 at the significant level p=0.005.


2021 ◽  
Vol 66 (3) ◽  
pp. 195-206
Author(s):  
Thuy Hoang Luu Thu ◽  
Mui Tran Thi ◽  
Vu Vuong Van ◽  
Ly Pham Thi ◽  
Cuc Pham Thi

Assessment of the degree of meteorological drought in Dak Lak province is carried out using the SPI index and the water balance index K in the period 1985 - 2019. The results show that: According to the SPI index, drought tends to occur more at the time of transition from the dry season to the rainy season, during the rainy season, and from the time of transition from the rainy season to the dry season. The K-index in the period 1985 - 2019 showed there was a dry period at the beginning of the year from January to April. The anomalous drought factor plays a very important role because its large influence can cause damages, and allows assessing the variability of rainfall and the impact of climate change on the region. The study and evaluation of meteorological drought have practical significance, supporting managers in making policies on water resource management, ensuring sustainable economic and social development in the context of global climate change.


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