Climate Change and Its Possible Impact in Groundwater Resource of the Kankai River Basin, East Nepal Himalaya

Increasing evidence of changing climate patterns is being observed, and the impact of this change on groundwater has a direct impact on the livelihood and economy of the region. The research focuses on the impacts of global temperature increase and changing precipitation on the groundwater resources of part of the Himalayan river system. The spatial and temporal variations of the hydro-meteorological data of the Kankai River Basin in East Nepal were analyzed using non-parametric Mann–Kendall tests and Sen’s Slope methods, whereas CanESM2 was used to predict the future precipitation scenarios, and an attempt has been made to evaluate the possible impacts on groundwater systems in the region. The temperature shows a significant warming trend (0.14–0.64 °C/decade); however, the precipitation trends suggest remarkable variation mostly at higher elevation. The average annual precipitation suggests a decrease of 1.82 mm/year and a similar decrement has been projected for the future. The groundwater in the region has been influenced by the changing climate and the condition may further be exaggerated by reduced recharge and increased evapotranspiration. This understanding of the impacts and climate scenarios will help the planners with better adaptation strategies, plans, and programs for a better society.

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Evaluation of Climate Change Impact on Groundwater Recharge in Groundwater Regions in Taiwan

Water ◽

10.3390/w13091153 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1153

Author(s):

Shih-Jung Wang ◽

Cheng-Haw Lee ◽

Chen-Feng Yeh ◽

Yong Fern Choo ◽

Hung-Wei Tseng

Keyword(s):

Climate Change ◽

Groundwater Recharge ◽

Climate Change Impact ◽

Groundwater Resources ◽

Regression Equations ◽

Impact Of Climate Change ◽

Groundwater Systems ◽

Change Impact ◽

The Impact ◽

Assessment Results

Climate change can directly or indirectly influence groundwater resources. The mechanisms of this influence are complex and not easily quantified. Understanding the effect of climate change on groundwater systems can help governments adopt suitable strategies for water resources. The baseflow concept can be used to relate climate conditions to groundwater systems for assessing the climate change impact on groundwater resources. This study applies the stable baseflow concept to the estimation of the groundwater recharge in ten groundwater regions in Taiwan, under historical and climate scenario conditions. The recharge rates at the main river gauge stations in the groundwater regions were assessed using historical data. Regression equations between rainfall and groundwater recharge quantities were developed for the ten groundwater regions. The assessment results can be used for recharge evaluation in Taiwan. The climate change estimation results show that climate change would increase groundwater recharge by 32.6% or decrease it by 28.9% on average under the climate scenarios, with respect to the baseline quantity in Taiwan. The impact of climate change on groundwater systems may be positive. This study proposes a method for assessing the impact of climate change on groundwater systems. The assessment results provide important information for strategy development in groundwater resources management.

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Application of SWAT in Hydrological Simulation of Complex Mountainous River Basin (Part II: Climate Change Impact Assessment)

Water ◽

10.3390/w13111548 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1548

Author(s):

Suresh Marahatta ◽

Deepak Aryal ◽

Laxmi Prasad Devkota ◽

Utsav Bhattarai ◽

Dibesh Shrestha

Keyword(s):

Climate Change ◽

River Basin ◽

Climate Models ◽

Assessment Tool ◽

Swat Model ◽

Global Climate Models ◽

Climate Data ◽

The Future ◽

The Impact ◽

Mountainous River

This study aims at analysing the impact of climate change (CC) on the river hydrology of a complex mountainous river basin—the Budhigandaki River Basin (BRB)—using the Soil and Water Assessment Tool (SWAT) hydrological model that was calibrated and validated in Part I of this research. A relatively new approach of selecting global climate models (GCMs) for each of the two selected RCPs, 4.5 (stabilization scenario) and 8.5 (high emission scenario), representing four extreme cases (warm-wet, cold-wet, warm-dry, and cold-dry conditions), was applied. Future climate data was bias corrected using a quantile mapping method. The bias-corrected GCM data were forced into the SWAT model one at a time to simulate the future flows of BRB for three 30-year time windows: Immediate Future (2021–2050), Mid Future (2046–2075), and Far Future (2070–2099). The projected flows were compared with the corresponding monthly, seasonal, annual, and fractional differences of extreme flows of the simulated baseline period (1983–2012). The results showed that future long-term average annual flows are expected to increase in all climatic conditions for both RCPs compared to the baseline. The range of predicted changes in future monthly, seasonal, and annual flows shows high uncertainty. The comparative frequency analysis of the annual one-day-maximum and -minimum flows shows increased high flows and decreased low flows in the future. These results imply the necessity for design modifications in hydraulic structures as well as the preference of storage over run-of-river water resources development projects in the study basin from the perspective of climate resilience.

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Global warming and forest fires in Canada

The Forestry Chronicle ◽

10.5558/tfc69290-3 ◽

1993 ◽

Vol 69 (3) ◽

pp. 290-293 ◽

Cited By ~ 47

Author(s):

Brian J. Stocks

Keyword(s):

Global Warming ◽

Forest Fire ◽

Forest Fires ◽

Fire Management ◽

Warming Trend ◽

Research Activities ◽

Forest Fire Management ◽

The Future ◽

Innovative Thinking ◽

The Impact

The looming possibility of global warming raises legitimate concerns for the future of the forest resource in Canada. While evidence of a global warming trend is not conclusive at this time, governments would be wise to anticipate, and begin planning for, such an eventuality. The forest fire business is likely to be affected both early and dramatically by any trend toward warmer and drier conditions in Canada, and fire managers should be aware that the future will likely require new and innovative thinking in forest fire management. This paper summarizes research activities currently underway to assess the impact of global warming on forest fires, and speculates on future fire management problems and strategies.

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An evaluation of the effect of future climate on runoff in the Dongjiang River basin, South China

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-368-257-2015 ◽

2015 ◽

Vol 368 ◽

pp. 257-262

Author(s):

K. Lin ◽

W. Zhai ◽

S. Huang ◽

Z. Liu

Keyword(s):

Climate Change ◽

River Basin ◽

South China ◽

Annual Runoff ◽

Future Climate ◽

Weather Data ◽

Future Climate Change ◽

Dongjiang River ◽

The Future ◽

The Impact

Abstract. The impact of future climate change on the runoff for the Dongjiang River basin, South China, has been investigated with the Soil and Water Assessment Tool (SWAT). First, the SWAT model was applied in the three sub-basins of the Dongjiang River basin, and calibrated for the period of 1970–1975, and validated for the period of 1976–1985. Then the hydrological response under climate change and land use scenario in the next 40 years (2011–2050) was studied. The future weather data was generated by using the weather generators of SWAT, based on the trend of the observed data series (1966–2005). The results showed that under the future climate change and LUCC scenario, the annual runoff of the three sub-basins all decreased. Its impacts on annual runoff were –6.87%, –6.54%, and –18.16% for the Shuntian, Lantang, and Yuecheng sub-basins respectively, compared with the baseline period 1966–2005. The results of this study could be a reference for regional water resources management since Dongjiang River provides crucial water supplies to Guangdong Province and the District of Hong Kong in China.

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Variations of Drought Tendency, Frequency, and Characteristics and Their Responses to Climate Change under CMIP5 RCP Scenarios in Huai River Basin, China

Water ◽

10.3390/w11102174 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2174 ◽

Cited By ~ 4

Author(s):

Jingcai Wang ◽

Hui Lin ◽

Jinbai Huang ◽

Chenjuan Jiang ◽

Yangyang Xie ◽

...

Keyword(s):

Climate Change ◽

River Basin ◽

Eastern China ◽

Cmip5 Models ◽

Drought Severity ◽

Global Circulation Models ◽

Huai River Basin ◽

Huai River ◽

The Future ◽

The Impact

Huai River Basin (HRB) is an important food and industrial production area and a frequently drought-affected basin in eastern China. It is necessary to consider the future drought development for reducing the impact of drought disasters. Three global circulation models (GCMs) from Coupled Model Intercomparison Project phase 5 (CMIP5), such as CNRM-CM5 (CNR), HadGEM2-ES (Had) and MIROC5 (MIR), were used to assessment the future drought conditions under two Representative Concentration Pathways (RCPs) scenarios, namely, RCP4.5 and RCP8.5. The standardized precipitation evapotranspiration index (SPEI), statistical method, Mann-Kendall test, and run theory were carried out to study the variations of drought tendency, frequency, and characteristics and their responses to climate change. The research showed that the three CMIP5 models differ in describing the future seasonal and annual variations of precipitation and temperature in the basin and thus lead to the differences in describing drought trends, frequency, and drought characteristics, such as drought severity, drought duration, and drought intensity. However, the drought trend, frequency, and characteristics in the future are more serious than the history. The drought frequency and characteristics tend to be strengthened under the scenario of high concentration of RCP8.5, and the drought trend is larger than that of low concentration of RCP4.5. The lower precipitation and the higher temperature are the main factors affecting the occurrence of drought. All three CMIP5 models show that precipitation would increase in the future, but it could not offset the evapotranspiration loss caused by significant temperature rise. The serious risk of drought in the future is still higher. Considering the uncertainty of climate models for simulation and prediction, attention should be paid to distinguish the effects of different models in the future drought assessment.

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Assessing the Potential Impact of Rising Production of Industrial Wood Pellets on Streamflow in the Presence of Projected Changes in Land Use and Climate: A Case Study from the Oconee River Basin in Georgia, United States

Water ◽

10.3390/w11010142 ◽

2019 ◽

Vol 11 (1) ◽

pp. 142 ◽

Cited By ~ 1

Author(s):

Surendra Shrestha ◽

Puneet Dwivedi ◽

S. McKay ◽

David Radcliffe

Keyword(s):

Land Use ◽

River Basin ◽

Land Use Changes ◽

Base Case ◽

Wood Pellets ◽

Wood Pellet ◽

Changing Climate ◽

Trade Offs ◽

The Impact ◽

Oconee River

This study examines the impact of projected land use changes in the context of growing production of industrial wood pellets coupled with expected changes in precipitation and temperature due to the changing climate on streamflow in a watershed located in the northeastern corner of the Oconee River Basin. We used the Soil and Water Assessment Tool (SWAT) for ascertaining any changes in streamflow over time. The developed model was calibrated over a seven-year period (2001–2007) and validated over another seven-year period (2008–2014). Any changes in streamflow were simulated for a combination of 10 land use and climate change cases, from 2015 to 2028, under the two scenarios of High and Low Demand for industrial wood pellets. Our results suggest that streamflow is relatively stable (<1% change) for land use and temperature-related cases relative to the base case of no change in land use and climate. However, changes in precipitation by ±10% lead to considerable changes (±25%) in streamflow relative to the base case. Based on our results, expected changes in precipitation due to the changing climate will determine any changes in the streamflow, rather than projected land use changes in the context of rising demand for industrial wood pellets for export purposes in the selected watershed, keeping land under urban areas as constant. This study contributes to our broader understanding of the sustainability of the transatlantic industrial wood pellet trade; however, we suggest undertaking similar research at a larger spatial scale over a longer time horizon for understanding trade-offs across carbon, biodiversity, and water impacts of the transatlantic industrial wood pellet trade.

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Simulation of the impact of climate change on runoff and drought in an arid and semiarid basin (the Hablehroud, Iran)

Applied Water Science ◽

10.1007/s13201-021-01494-2 ◽

2021 ◽

Vol 11 (10) ◽

Author(s):

Morteza Lotfirad ◽

Arash Adib ◽

Jaber Salehpoor ◽

Afshin Ashrafzadeh ◽

Ozgur Kisi

Keyword(s):

Climate Change ◽

River Basin ◽

Baseline Period ◽

Hydrological Drought ◽

Downward Trend ◽

Future Period ◽

Impact Of Climate Change ◽

The Future ◽

Rcp 8.5 ◽

The Impact

AbstractThis study evaluates the impact of climate change (CC) on runoff and hydrological drought trends in the Hablehroud river basin in central Iran. We used a daily time series of minimum temperature (Tmin), maximum temperature (Tmax), and precipitation (PCP) for the baseline period (1982–2005) analysis. For future projections, we used the output of 23 CMIP5 GCMs and two scenarios, RCP 4.5 and RCP 8.5; then, PCP, Tmin, and Tmax were projected in the future period (2025–2048). The GCMs were weighed based on the K-nearest neighbors algorithm. The results indicated a rising temperature in all months and increasing PCP in most months throughout the Hablehroud river basin's areas for the future period. The highest increase in the Tmin and Tmax in the south of the river basin under the RCP 8.5 scenario, respectively, was 1.87 °C and 1.80 °C. Furthermore, the highest reduction in the PCP was 54.88% in August under the RCP 4.5 scenario. The river flow was simulated by the IHACRES rainfall-runoff model. The annual runoff under the scenarios RCP 4.5 and RCP 8.5 declined by 11.44% and 13.13%, respectively. The basin runoff had a downward trend at the baseline period; however, it will have a downward trend in the RCP 4.5 scenario and an upward trend in the RCP 8.5 scenario for the future period. This study also analyzed drought by calculating the streamflow drought index for different time scales. Overall, the Hablehroud river basin will face short-term and medium-term hydrological drought in the future period.

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Agricultural Water Productivity-Based Hydro-Economic Modeling for Optimal Crop Pattern and Water Resources Planning in the Zarrine River Basin, Iran, in the Wake of Climate Change

Sustainability ◽

10.3390/su10113953 ◽

2018 ◽

Vol 10 (11) ◽

pp. 3953 ◽

Cited By ~ 9

Author(s):

Farzad Emami ◽

Manfred Koch

Keyword(s):

Climate Change ◽

River Basin ◽

Groundwater Resources ◽

Water Productivity ◽

Economic Benefits ◽

Management Tool ◽

Precipitation Pattern ◽

Agricultural Water ◽

The Future ◽

Crop Area

For water-stressed regions/countries, like Iran, improving the management of agricultural water-use in the wake of climate change and increasingly unsustainable demands is of utmost importance. One step further is then the maximization of the agricultural economic benefits, by properly adjusting the irrigated crop area pattern to optimally use the limited amount of water available. To that avail, a sequential hydro-economic model has been developed and applied to the agriculturally intensively used Zarrine River Basin (ZRB), Iran. In the first step, the surface and groundwater resources, especially, the inflow to the Boukan Dam, as well as the potential crop yields are simulated using the Soil Water Assessment Tool (SWAT) hydrological model, driven by GCM/QM-downscaled climate predictions for three future 21th-century periods under three climate RCPs. While in all nine combinations consistently higher temperatures are predicted, the precipitation pattern are much more versatile, leading to corresponding changes in the future water yields. Using the basin-wide water management tool MODSIM, the SWAT-simulated water available is then optimally distributed across the different irrigation plots in the ZRB, while adhering to various environmental/demand priority constraints. MODSIM is subsequently coupled with CSPSO to optimize (maximize) the agro-economic water productivity (AEWP) of the various crops and, subsequently, the net economic benefit (NEB), using crop areas as decision variables, while respecting various crop cultivation constraints. Adhering to political food security recommendations for the country, three variants of cereal cultivation area constraints are investigated. The results indicate considerably-augmented AEWPs, resulting in a future increase of the annual NEB of ~16% to 37.4 Million USD for the 65%-cereal acreage variant, while, at the same time, the irrigation water required is reduced by ~38%. This NEB-rise is achieved by augmenting the total future crop area in the ZRB by about 47%—indicating some deficit irrigation—wherefore most of this extension will be cultivated by the high AEWP-yielding crops wheat and barley, at the expense of a tremendous reduction of alfalfa acreage. Though presently making up only small base acreages, depending on the future period/RCP, tomato- and, less so, potato- and sugar beet-cultivation areas will also be increased significantly.

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Spatio-temporal variability of streamflow in the Huaihe River Basin, China: climate variability or human activities?

Hydrology Research ◽

10.2166/nh.2017.155 ◽

2017 ◽

Vol 49 (1) ◽

pp. 177-193 ◽

Cited By ~ 11

Author(s):

Zharong Pan ◽

Xiaohong Ruan ◽

Mingkai Qian ◽

Jian Hua ◽

Nan Shan ◽

...

Keyword(s):

Climate Variability ◽

River Basin ◽

Human Activities ◽

River System ◽

Kendall Test ◽

Driving Factor ◽

Huaihe River Basin ◽

Huaihe River ◽

The Huaihe River ◽

The Impact

AbstractThe water shortage in the Huaihe River Basin (HRB), China, has been aggravated by population growth and climate change. To identify the characteristics of streamflow change and assess the impact of climate variability and human activities on hydrological processes, approximately 50 years of natural and observed streamflow data from 20 hydrological stations were examined. The Mann–Kendall test was employed to detect trends. The results showed the following. (i) Both the natural and the observed streamflow in the HRB present downward trends, and the decreasing rate of observed streamflow is generally faster than that of the natural streamflow. (ii) For the whole period, negative trends dominate in the four seasons in the basin. The highest decreasing trends for two kinds of streamflow both occurred in spring, and the lowest ones were in autumn and winter. (iii) Based on the above analysis and quantifying assessment for streamflow decrease, human activity was the main driving factor in the Xuanwu (80.78%), Zhuangqiao (79.92%), Yongcheng (74.80%), and Mengcheng (64.73%) stations which all belong to the Huaihe River System (HRS). On the other hand, climate variability was the major driving factor in the Daguanzhuang (68.89%) and Linyi (63.38%) stations which all belong to the Yishusi River System (YSR).

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Hygienic Condition of Different Water Sources in the Kharaa River Basin, Mongolia in the Light of a Rapid Warming Trend

Atmosphere ◽

10.3390/atmos11101113 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1113

Author(s):

Bolor-Erdene Ochirbold ◽

Ariuntuya Tserendorj ◽

Katja Westphal ◽

Daniel Karthe

Keyword(s):

River Basin ◽

Sewage Treatment ◽

River System ◽

Warming Trend ◽

Water Sources ◽

Data Availability ◽

Fecal Coliforms ◽

Most Probable Number ◽

Probable Number ◽

Urban Sewage

Mongolia is a water-scarce land-locked country, and available water resources are utilized for multiple purposes including irrigation, food preparation, drinking water for livestock and people. Limited data availability on water hygiene means that the related risks to public health are only partially understood. This is particularly problematic due to the widespread use of unimproved water sources such as surface water and water from simple shallow wells. Based on two field surveys in the Kharaa River Basin in spring 2017 and 2018, we assessed the presence and quantity of total coliforms (TC), fecal coliforms (FC), and E. coli bacteria in surface waters and wells and investigated potential linkages between temperature and hygiene. In the Kharaa River and its tributaries, TC concentrations averaged at a most probable number of (MPN) of 754 ± 761 per 100 mL and FC concentrations at an MPN of 31 ± 33. Only small and non-significant correlations between coliform concentrations and temperature were identified. Coliforms concentrations in wells were lower (average MPN for TC: 550 ± 1286, and for FC 58 ± 253). There was considerable variation between wells, with moderate but significant correlations between temperature and bacterial counts. Low water temperatures in April and May (just above freezing to less than 6.5 °C in wells and 7.5 °C to 14.5 °C in the river system) and the positive correlations between temperature and coliform concentrations particularly for well samples indicate that further warming is likely to increase the risks of microbiological water pollution. In the future, this should be complemented by modeling at a watershed scale. This should include the consideration of a trend towards stronger rainfall events, changes in livestock density, and urban sewage treatment and discharge, which are other likely drivers of changes in water hygiene.

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