Climate change impacts on the hydrological cycle

Arid ecosystems are extremely vulnerable to climate change, which is considered one of the serious global environmental issues that can cause critical challenges to the hydrological cycle in arid ecosystems. This work focused on assessing the effectiveness of supplemental irrigation to improve the actual soil moisture content in arid ecosystems and considering climate change impacts on soil moisture. The study was conducted at two fenced protected sites in Kuwait. The first site is naturally covered with Rhanterietum epapposum, whereas the other study site is a supplemented irrigated site, containing several revegetated native plants. The results showed that supplemental irrigation highly improved soil moisture (∆SM) during the winter season by >50%. However, during the summer season, the rainfed and irrigated site showed low ∆SM due to the high temperature and high evapotranspiration (ET) rates. We also found that ∆SM would negatively get impacted by climate change. The climate change projection results showed that temperature would increase by 12%–23%, ET would increase by 17%–19%, and precipitation would decrease by 31%–46% by 2100. Such climate change impacts may also shift the current ecosystem from an arid to a hyper-arid ecosystem. Therefore, we concluded that irrigation is a practical option to support the ∆SM during the low-temperature months only (spring and winter) since the results did not show any progress during the summer season. It is also essential to consider the possibility of future shifting in ecosystems and plant communities in restoration and revegetation planning.

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Linking atmospheric circulation to daily rainfall patterns across the Murrumbidgee River Basin

Water Science & Technology ◽

10.2166/wst.2003.0445 ◽

2003 ◽

Vol 48 (7) ◽

pp. 233-240 ◽

Cited By ~ 16

Author(s):

S.P. Charles ◽

B.C. Bates ◽

N.R. Viney

Keyword(s):

Climate Change ◽

Atmospheric Circulation ◽

River Basin ◽

Climate Model ◽

Hydrological Cycle ◽

Rainfall Variability ◽

Daily Rainfall ◽

Climate Change Impacts ◽

River Health ◽

Climate Model Simulations

The hydrological cycle in Australia covers an extraordinary range of climatic and hydrologic regimes. It is now widely accepted that Australian hydrology is significantly different from all other regions and continents with the partial exception of southern Africa. Rainfall variability is very high in almost all regions with respect to amount and the lengths of wet and dry spells. These factors are keys to the behaviour and health of Australian aquatic ecosystems and water resources. Thus assessment of how rainfall may change under a potential future climate is critical. For a case study of the Murrumbidgee River Basin (MRB), a statistical downscaling model that links broad scale atmospheric circulation to multi-site, daily precipitation is assessed using observed data. This model can be driven with climate model simulations to produce rainfall scenarios at the scale required by impacts models. These can then be used in probabilistic risk assessments of climate change impacts on river health. These issues will be discussed in the context of assessing the potential impacts of precipitation changes due to projected climate change on river health.

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High-Resolution Coupled Climate Runoff Simulations of Seasonal Snowfall over Colorado: A Process Study of Current and Warmer Climate

Journal of Climate ◽

10.1175/2010jcli3985.1 ◽

2011 ◽

Vol 24 (12) ◽

pp. 3015-3048 ◽

Cited By ~ 280

Author(s):

Roy Rasmussen ◽

Changhai Liu ◽

Kyoko Ikeda ◽

David Gochis ◽

David Yates ◽

...

Keyword(s):

Climate Change ◽

Global Warming ◽

High Resolution ◽

Snow Water Equivalent ◽

Hydrological Cycle ◽

Climate Change Impacts ◽

Grid Spacing ◽

Total Runoff ◽

Lower Elevation ◽

Topographic Reduction

Abstract Climate change is expected to accelerate the hydrologic cycle, increase the fraction of precipitation that is rain, and enhance snowpack melting. The enhanced hydrological cycle is also expected to increase snowfall amounts due to increased moisture availability. These processes are examined in this paper in the Colorado Headwaters region through the use of a coupled high-resolution climate–runoff model. Four high-resolution simulations of annual snowfall over Colorado are conducted. The simulations are verified using Snowpack Telemetry (SNOTEL) data. Results are then presented regarding the grid spacing needed for appropriate simulation of snowfall. Finally, climate sensitivity is explored using a pseudo–global warming approach. The results show that the proper spatial and temporal depiction of snowfall adequate for water resource and climate change purposes can be achieved with the appropriate choice of model grid spacing and parameterizations. The pseudo–global warming simulations indicate enhanced snowfall on the order of 10%–25% over the Colorado Headwaters region, with the enhancement being less in the core headwaters region due to the topographic reduction of precipitation upstream of the region (rain-shadow effect). The main climate change impacts are in the enhanced melting at the lower-elevation bound of the snowpack and the increased snowfall at higher elevations. The changes in peak snow mass are generally near zero due to these two compensating effects, and simulated wintertime total runoff is above current levels. The 1 April snow water equivalent (SWE) is reduced by 25% in the warmer climate, and the date of maximum SWE occurs 2–17 days prior to current climate results, consistent with previous studies.

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Climate Change Impacts on Inflows into Lake Eppalock Reservoir from Upper Campaspe Catchment

Hydrology ◽

10.3390/hydrology8030108 ◽

2021 ◽

Vol 8 (3) ◽

pp. 108

Author(s):

Abdullah Gokhan Yilmaz ◽

Serter Atabay ◽

Kimia Haji Amou Assar ◽

Monzur Alam Imteaz

Keyword(s):

Climate Change ◽

Climate Models ◽

Hydrological Cycle ◽

Climate Change Impacts ◽

Irrigation District ◽

Climate Data ◽

Adaptation Measures ◽

Climate Change Effects ◽

Monthly Streamflow ◽

Dry Out

Climate change has significant effects on societies and ecosystems. Due to the strong link between climate and the hydrological cycle, water resources is one of the most affected fields by climate change. It is of great importance to investigate climate change effects on streamflows by producing future streamflow projections under different scenarios to create adaptation measures and mitigate potential impacts of climate change. The Upper Campaspe Catchment (UCC), located at North Central Victoria in Australia, is a significant catchment as it provides a large portion of total inflow to the Lake Eppalock Reservoir, which supplies irrigation to the Campaspe Irrigation district and urban water to Bendigo, Heathcote, and Ballarat cities. In this study, climate change effects on monthly streamflows in the UCC was investigated using high resolution future climate data from CSIRO and MIROC climate models in calibrated IHACRES hydrological model. The IHACRES model was found to be very successful to simulate monthly streamflow in UCC. Remarkable streamflow reductions were projected based on the climate input from both models (CSIRO and MIROC). According to the most optimistic scenario (with the highest projected streamflows) by the MIROC-RCP4.5 model in near future (2035–2064), the Upper Campaspe River will completely dry out from January to May. The worst scenario (with the lowest streamflow projection) by the CSIRO-RCP8.5 model in the far future (2075–2104) showed that streamflows will be produced only for three months (July, August, and September) throughout the year. Findings from this study indicated that climate change will have significant adverse impacts on reservoir inflow, operation, water supply, and allocation in the study area.

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Climate change and water resources in the Lower Mekong River Basin: putting adaptation into the context

Journal of Water and Climate Change ◽

10.2166/wcc.2010.009 ◽

2010 ◽

Vol 1 (2) ◽

pp. 103-117 ◽

Cited By ~ 60

Author(s):

M. Keskinen ◽

S. Chinvanno ◽

M. Kummu ◽

P. Nuorteva ◽

A. Snidvongs ◽

...

Keyword(s):

Climate Change ◽

River Basin ◽

Climate Change Adaptation ◽

Environmental Changes ◽

Hydrological Cycle ◽

Climate Change Impacts ◽

Mekong River ◽

Adaptation To Climate Change ◽

Mekong River Basin ◽

Spatial And Temporal Scales

Adaptation to climate change has become one of the focal points of current development discussion. This article summarises the findings from a multidisciplinary research project looking at climate change impacts and adaptation in the Mekong River Basin in Southeast Asia. The research highlights the central role that the hydrological cycle has in mediating climate change impacts on ecosystems and societies. The findings indicate that climate change should not be studied in isolation, as there are several other factors that are affecting the hydrological cycle. In the Mekong, the most important such factor is the on-going hydropower development that is likely to induce changes at least as radical as climate change, but with shorter timescales. The article concludes that climate change adaptation should broaden its view to consider environmental changes likely to occur due to different factors at various spatial and temporal scales. It is also important to recognise that climate change adaptation is a dynamic, development-orientated process that should consider also broader socio-political context. To enable this, we propose that an area-based adaptation approach should be used more actively to complement the dominant sector-based approaches.

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Quantifying the effect of dams in reducing global flood exposure under climate change

10.5194/egusphere-egu21-10453 ◽

2021 ◽

Author(s):

Julien Boulange ◽

Naota Hanasaki ◽

Dai Yamazaki ◽

Yadu Pokhrel

Keyword(s):

Climate Change ◽

Flood Risk ◽

Greenhouse Gas Emission ◽

Hydrological Cycle ◽

Climate Change Impacts ◽

Flood Protection ◽

Population Exposure ◽

Water Regulation ◽

Catchment Scale ◽

Flood Exposure

Flood risk was reported to increase in the future due to climate change and population growth. While recent and earlier studies have derived plausible climate change impacts on global flood risk, dams have never been explicitly implemented into simulation tools. Currently, about half of major river systems worldwide are regulated by dams and more than 3,700 major dams are planned or under construction. Consequently, to realistically assess population exposure to present and future floods, current and future dam landscapes must be integrated into existing flood modeling frameworks.In this research, the role of dams on future flood risk under climate change is quantified by simulating the global hydrological cycle, including floodplain dynamics, and considering flow regulation by dams.&#160;The global population exposed to historical once-in-100-year floods in our simulation was 9.4 million people, relatively close to the estimate of 5.6 million people indicated in a previous study (Hirabayashi et al., 2013) and the Dartmouth Flood Observatory database which estimated this number as 11.9 million people. Downstream of dams, the number of people exposed to the historical once-in-100-year floods were 7.2 and 13.4 million on average over 2006&#8211;2099 given a low and a medium-high greenhouse gas emission trajectory (RCP2.6 and RCP6.0, respectively). By the end of the 21st century, the populations exposed to flooding below dams decreased on average by 20.6% and 12. 9% for the two trajectories compared to simulations not accounting for the flow regulations produced by dams.At the catchment scale, by considering water regulation in densely populated and heavily water regulated catchments, the occurrence of flood events largely decreases compared to projections not accounting for water regulation. Over the 2070&#8211;2099 period and for 14 catchments, the annual flooded area shrank by, on average (first and third quartiles given in bracket), 22.5% (19.8&#8211;40.5) and 25.9% (12.1&#8211;34.5) for RCP2.6 and RCP6.0 respectively.To maintain the levels of flood protection that dams have provided, new dam operations will be required to offset the effect of climate change, possibly negatively affecting energy production and water storage. In addition, precise and reliable hydro-meteorological forecasts will be invaluable for enhancing flood protection and avoid excessive outflows. Given the many negative environmental and social impacts of dams, comprehensive assessments that consider both potential benefits and adverse effects are necessary for the sustainable development of water resources.

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