Will future climate change increase the risk of violating minimum flow and maximum temperature thresholds below dams in the Pacific Northwest?

Nowadays, the hydrological cycle which alters river discharge and water availability is affected by climate change. Therefore, the understanding of climate change is curial for the security of hydrologic conditions of river basins. The main purpose of this study is to assess the projections of future climate across the Upper Ayeyarwady river basin for its sustainable development and management of water sector for this area. Global Ten climate Models available from CMIP5 represented by the IPCC for its fifth Assessment Report were bias corrected using linear scaling method to generate the model error. Among the GCMs, a suitable climate model for each station is selected based on the results of performance indicators (R2 and RMSE). Future climate data are projected based on the selected suitable climate models by using future climate scenarios: RCP2.6, RCP4.5, and RCP8.5. According to this study, future projection indicates to increase in precipitation amounts in the rainy and winter season and diminishes in summer season under all future scenarios. Based on the seasonal temperature changes analysis for all stations, the future temperature are predicted to steadily increase with higher rates during summer than the other two seasons and it can also be concluded that the monthly minimum temperature rise is a bit larger than the maximum temperature rise in all seasons.

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Analyzing the future climate change of Upper Blue Nile River Basin (UBNRB) using statistical down scaling techniques

10.5194/hess-2016-543 ◽

2016 ◽

Cited By ~ 2

Author(s):

Dagnenet Fenta Mekonnen ◽

Markus Disse

Keyword(s):

Climate Change ◽

River Basin ◽

Future Climate ◽

Maximum Temperature ◽

Future Climate Change ◽

Mean Annual Precipitation ◽

Nile River ◽

Climate Variables ◽

Increasing Trend ◽

Blue Nile River Basin

Abstract. Climate change is becoming one of the most arguable and threatening issues in terms of global context and their responses to environment and socio/economic drivers. Its direct impact becomes critical for water resource development and indirectly for agricultural production, environmental quality, economic development, social well-being. However, a large uncertainty between different Global Circulation Models (GCM) and downscaling methods exist that makes reliable conclusions for a sustainable water management difficult. In order to understand the future climate change of the Upper Blue Nile River Basin, two widely used statistical down scaling techniques namely LARS-WG and SDSM models were applied. Six CMIP3 GCMs for LARS-WG (CSIRO-MK3, ECHAM5-OM, MRI-CGCM2.3.2, HaDCM3, GFDL-CM2.1, CCSM3) model while HadCM3 GCM and canESM2 from CMIP5 GCMs for SDSM were used for climate change analysis. The downscaled precipitation results from the prediction of the six GCMs by LARS WG showed inconsistency and large inter model variability, two GCMs showed decreasing trend while 4 GCMs showed increasing in the range from −7.9 % to +43.7 % while the ensemble mean of the six GCM result showed increasing trend ranged from 1.0 % to 14.4 %. NCCCS GCM predicted maximum increase in mean annual precipitation. However, the projection from HadCM3 GCM is consistent with the multi-model average projection, which predicts precipitation increase from 1.7 % to 16.6 %. Conversely, the result from all GCMs showed a similar continuous increasing trend for maximum temperature (Tmax) and minimum temperature (Tmin) in all three future periods. The change for mean annual Tmax may increase from 0.4 °c to 4.3 °c whereas the change for mean annual Tmin may increase from 0.3 °c to 4.1 °c. Meanwhile, the result from SDSM showed an increasing trend for all three climate variables (precipitation, minimum and maximum temperature) from both HadCM3 and canESM2 GCMs. The relative change of mean annual precipitation range from 2.1 % to 43.8 % while the change for mean annual Tmax and Tmin may increase from 0.4 °c to 2.9 °c and from 0.3 °c to 1.6 °c respectively. The change in magnitude for precipitation is higher in RCP8.5 scenarios than others as expected. The present result illustrate that both down scaling techniques have shown comparable and good ability to simulate the current local climate variables which can be adopted for future climate change study with high confidence for the UBNRB. In order to see the comparative downscaling results from the two down scaling techniques, HadCM3 GCM of A2 scenario was used in common. The result obtained from the two down scaling models were found reasonably comparable and both approaches showed increasing trend for precipitation, Tmax and Tmin. However, the analysis of the downscaled climate data from the two techniques showed, LARS WG projected a relatively higher increase than SDSM.

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Snowfall and snowpack in the Western U.S. as captured by convection permitting climate simulations: current climate and pseudo global warming future climate

Climate Dynamics ◽

10.1007/s00382-021-05805-w ◽

2021 ◽

Author(s):

Kyoko Ikeda ◽

Roy Rasmussen ◽

Changhai Liu ◽

Andrew Newman ◽

Fei Chen ◽

...

Keyword(s):

Climate Change ◽

Global Warming ◽

Pacific Northwest ◽

Climate Model ◽

Future Climate ◽

Climate Simulation ◽

Climate Change Signal ◽

Mountain Ranges ◽

The Pacific ◽

Climate Simulations

AbstractThis study examines current and future western U.S. snowfall and snowpack through current and future climate simulations with a 4-km horizontal grid spacing cloud permitting regional climate model over the entire CONtinental U.S. for a 13-year period between 2001 and 2013. At this horizontal resolution, the spatiotemporal distribution of the orographic snowfall and snowpack is well captured partly due to the ability of the model to realistically simulate mesoscale and microphysical features such as orographically induced updrafts driving clouds and precipitation. The historical simulation well captures the observed snowfall and snowpack amounts and pattern in the western U.S. The future climate simulation uses the Pseudo-Global Warming approach, taking the climate change signal from CMIP5 multi-model ensemble-mean difference between 2070–2099 and 1976–2005. The results show that the thermodynamic impacts of climate change in the western U.S. can be characterized considering mountain ranges in two distinct geographic regions: the mountain ranges close to the Pacific Ocean (coastal ranges) and those in the inter-mountain west. Climate change out to 2100 significantly impacts all aspects of the water cycle, with pronounced climate change response in the coastal ranges. A notable result is that the snowpack in the Pacific Northwest is predicted to decrease by ~ 70% by 2100. Trends of this magnitude have already been observed in the historical data and in previous studies. The current Pseudo Global Warming future climate simulation and previous global climate simulations all suggest that these trends will continue to the point that most snowpack will be gone by 2100 in the Pacific Northwest for the most aggressive RCP8.5 climate scenario, even if annual precipitation increases by 10%. Future work will focus on extending the current convective permitting results to a full climate change simulation allowing for dynamical changes in the flow.

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Seasonal Variability of Historical and Projected Future Climate in the Kathmandu Valley

Technical Journal ◽

10.3126/tj.v2i1.32847 ◽

2020 ◽

Vol 2 (1) ◽

pp. 108-120

Author(s):

Suraj Lamichhane ◽

Keshav Basnet ◽

Nirmal Prasad Baral ◽

Tek Bahadur Katuwal ◽

Upendra Subedi

Keyword(s):

Climate Change ◽

Climate Model ◽

Average Rate ◽

Climatic Variability ◽

Future Climate ◽

Capital City ◽

Maximum Temperature ◽

Future Climate Change ◽

Kathmandu Valley ◽

The Future

Anthropogenic activities are the major drivers of climate change and the climatic variability is the major threat for the world development especially in Nepal. The Kathmandu Valley (KV) is the most urbanized capital city of Nepal that has sensed the climatic variation in terms of increase in temperature, precipitation, runoff, and flood for few decades. For the adaptation of climatic variability, historical and future climate change is depicted by the trend, seasonal, and yearly variation analysis using climate models based on observed data. Historically, minimum temperatures of the all seasons are in increasing and the seasonal average rate of precipitation in the KV watershed is declining. After analysis of the projected future climate using climate model (ACCESS-CSIRO-CCAM, CNRM-CM5 and CCSM4) with two representative concentration pathways (RCP) scenarios (i.e., RCP4.5 and RCP8.5), minimum and maximum temperature in the future (up to 2050) is increased by 0.66°C – 0.6°C in RCP 4.5 and 1.21°C –1.04°C in RCP8.5 scenario. The rise in temperature means the warmer day will be increased and the erratic behavior of the precipitation will be expected in the future and the basin is expected to be drier in dry season and wetter in wet season. The analysis provides the alternative information for the planner for better planning, management, and adaptation strategy.

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Ensemble Projection of Future Climate and Surface Water Supplies in the North Saskatchewan River Basin above Edmonton, Alberta, Canada

Water ◽

10.3390/w13172425 ◽

2021 ◽

Vol 13 (17) ◽

pp. 2425

Author(s):

Muhammad Rehan Anis ◽

David J. Sauchyn

Keyword(s):

Climate Change ◽

Surface Water ◽

River Basin ◽

Climate Model ◽

Regional Climate ◽

Future Climate ◽

Maximum Temperature ◽

Future Climate Change ◽

Water Supplies ◽

The North

Changes in temperature and precipitation are expected to alter the seasonal distribution of surface water supplies in snowmelt-dominated watersheds. A realistic assessment of future climate change and inter-annual variability is required to meet a growing demand for water supplies in all major use sectors. This study focuses on changes in climate and runoff in the North Saskatchewan River Basin (NSRB) above Edmonton, AB, Canada, using the MESH (Modélisation Environnementale communautaire—Surface Hydrology) model. The bias-corrected ensemble of Canadian Regional Climate Model (CanRCM4) data is used to drive MESH for two 60-year time periods, a historical baseline (1951–2010) and future projection (2041–2100), under Representative Concentration Pathway (RCP) 8.5. The precipitation is projected to increase in every season, there is significant trend in spring (0.62) and fall (0.41) and insignificant in summer (0.008). Winter extreme minimum temperature and summer extreme maximum temperature are increasing by 2–3 °C in the near future and 5–6 °C in the far future. Annual runoff increases by 19% compared to base period. The results reveal long-term hydrological variability enabling water resource managers to better prepare for climate change and extreme events to build more resilient systems for future water demand in the NSRB.

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