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

2016 ◽  
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.

scholarly journals Climate Change Impact Assessment on the Precipitation over the Ghataprabha Sub-Basin, India under Future Climate Change Scenarios

2021 ◽  
Author(s):  
Nagendra Reddy ◽  
Nagraj S Patil ◽  
Rajashekhar S Laddimath
Keyword(s):  
Climate Change ◽  
Global Climate ◽  
Global Climate Model ◽  
Percentage Change ◽  
Maximum Temperature ◽  
Future Climate Change ◽  
Climate Change Scenarios ◽  
Climate Variables ◽  
Rcp Scenarios ◽  
Increasing Trend

Abstract The present study has been taken up to quantify the possible impacts of the climate change on the climate variables using the outputs of global climate models datasets over the Ghataprabha Sub-basin. The climate variables (precipitation, maximum and minimum temperature) data from the five selected global climate model dataset were downscaled using change factor method under four representative concentration pathway (RCP 2.6, 4.5, 6.0, and 8.5) scenarios for future periods near-century (2010-2039), mid-century (2040-2069), and end-century (2070-2099). The downscaled results of all the five models were ensembled using multi-model ensembling method to reduce the uncertainty in the projected results and the percentage change in the climate variables were shown with respect to the historical/baseline period (1961-1990) using spatial plots and histograms. The future projected results shows that percentage change in the annual mean precipitation with respect to the historical (1961-1990), is decreasing for most of the grids in the study area during the near-century while during mid and end centuries it shows an increasing trend across all the four RCP scenarios. The average daily minimum and maximum temperature with respect to the historical (1961-1990) values were showing an increasing trend in the study area during the near, mid, and end centuries across all the four RCP scenarios. Further, study also analysed the percentage change in 100-year return level over the study area.

scholarly journals Analyzing the future climate change of Upper Blue Nile River basin using statistical downscaling techniques

2018 ◽  
Vol 22 (4) ◽  
pp. 2391-2408 ◽  
Author(s):  
Dagnenet Fenta Mekonnen ◽  
Markus Disse
Keyword(s):  
Climate Change ◽  
River Basin ◽  
Statistical Downscaling ◽  
Nile River ◽  
Climate Variables ◽  
Climate Scenarios ◽  
Comparative Performance ◽  
Ensemble Mean ◽  
Blue Nile River Basin ◽  
Relative Change

Abstract. Climate change is becoming one of the most threatening issues for the world today in terms of its global context and its response to environmental and socioeconomic drivers. However, large uncertainties between different general circulation models (GCMs) and coarse spatial resolutions make it difficult to use the outputs of GCMs directly, especially for sustainable water management at regional scale, which introduces the need for downscaling techniques using a multimodel approach. This study aims (i) to evaluate the comparative performance of two widely used statistical downscaling techniques, namely the Long Ashton Research Station Weather Generator (LARS-WG) and the Statistical Downscaling Model (SDSM), and (ii) to downscale future climate scenarios of precipitation, maximum temperature (Tmax) and minimum temperature (Tmin) of the Upper Blue Nile River basin at finer spatial and temporal scales to suit further hydrological impact studies. The calibration and validation result illustrates that both downscaling techniques (LARS-WG and SDSM) have shown comparable and good ability to simulate the current local climate variables. Further quantitative and qualitative comparative performance evaluation was done by equally weighted and varying weights of statistical indexes for precipitation only. The evaluation result showed that SDSM using the canESM2 CMIP5 GCM was able to reproduce more accurate long-term mean monthly precipitation but LARS-WG performed best in capturing the extreme events and distribution of daily precipitation in the whole data range. Six selected multimodel CMIP3 GCMs, namely HadCM3, GFDL-CM2.1, ECHAM5-OM, CCSM3, MRI-CGCM2.3.2 and CSIRO-MK3 GCMs, were used for downscaling climate scenarios by the LARS-WG model. The result from the ensemble mean of the six GCM showed an increasing trend for precipitation, Tmax and Tmin. The relative change in precipitation ranged from 1.0 to 14.4 % while the change for mean annual Tmax may increase from 0.4 to 4.3 ∘C and the change for mean annual Tmin may increase from 0.3 to 4.1 ∘C. The individual result of the HadCM3 GCM has a good agreement with the ensemble mean result. HadCM3 from CMIP3 using A2a and B2a scenarios and canESM2 from CMIP5 GCMs under RCP2.6, RCP4.5 and RCP8.5 scenarios were downscaled by SDSM. The result from the two GCMs under five different scenarios agrees with the increasing direction of three climate variables (precipitation, Tmax and Tmin). The relative change of the downscaled mean annual precipitation ranges from 2.1 to 43.8 % while the change for mean annual Tmax and Tmin may increase in the range from 0.4 to 2.9 ∘C and from 0.3 to 1.6 ∘C respectively.

scholarly journals Future streamflow assessment in the Haihe River basin located in northern China using a regionalized variable infiltration capacity model based on 18 CMIP5 GCMs

2019 ◽  
Vol 11 (4) ◽  
pp. 1551-1569
Author(s):  
Zhenxin Bao ◽  
Jianyun Zhang ◽  
Xiaolin Yan ◽  
Guoqing Wang ◽  
Junliang Jin ◽  
...  
Keyword(s):  
Climate Change ◽  
River Basin ◽  
Future Climate ◽  
Future Climate Change ◽  
Haihe River Basin ◽  
Variable Infiltration Capacity ◽  
Infiltration Capacity ◽  
Haihe River ◽  
Increasing Trend ◽  
The Haihe River Basin

Abstract The impact of future climate change on streamflow is assessed in the Haihe River basin (HRB) by the Variable Infiltration Capacity (VIC) model, using the outputs from 18 general circulation models (GCMs) of the Coupled Model Inter-comparison Project Phase 5 (CMIP5). Three Representative Concentration Pathway (RCP) scenarios have been used, including RCP2.6, RCP4.5, and RCP8.5. Based on the model parameters calibration in six catchments in the HRB and parameter regionalization, the hydrological simulation for the whole HRB denotes good performance of the VIC model. Taking the period 1961–1990 as a baseline period, the outputs from the GCMs indicate that the HRB will become warmer and wetter in the 21st century (2010–2099). There might be an increasing trend for the streamflow in the HRB under future climate change scenarios. For example, in the 2050s (2040–2069), the streamflow may increase by 12%, 28%, and 24% under the RCP2.6, RCP4.5, and RCP8.5 scenarios, respectively. Monthly, the highest and lowest increase in streamflow is in dry and wet seasons, respectively. Spatially, the increasing trend for streamflow in the north HRB is higher than that in the south HRB. The uncertainty from the GCMs and climatic scenarios should be further focused.

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

Water ◽  
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.

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

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.

Future Climate Change Projections of the Kabul River Basin Using a Multi-model Ensemble of High-Resolution Statistically Downscaled Data

2018 ◽  
Vol 2 (3) ◽  
pp. 477-497 ◽  
Author(s):  
Syed Ahsan Ali Bokhari ◽  
Burhan Ahmad ◽  
Jahangir Ali ◽  
Shakeel Ahmad ◽  
Haris Mushtaq ◽  
...  
Keyword(s):  
Climate Change ◽  
High Resolution ◽  
River Basin ◽  
Future Climate ◽  
Future Climate Change ◽  
Model Ensemble ◽  
Climate Change Projections ◽  
Kabul River

scholarly journals Climate change impact on river flow extremes in the Upper Blue Nile River basin

2018 ◽  
Vol 10 (4) ◽  
pp. 759-781 ◽  
Author(s):  
Hadush K. Meresa ◽  
Mulusew T. Gatachew
Keyword(s):  
Climate Change ◽  
River Basin ◽  
Climate Change Impact ◽  
River Flow ◽  
Nile River ◽  
Hydrological Models ◽  
Hydrological Extremes ◽  
Dry Spell ◽  
Change Impact ◽  
Blue Nile River Basin

Abstract This paper aims to study climate change impact on the hydrological extremes and projected precipitation extremes in far future (2071–2100) period in the Upper Blue Nile River basin (UBNRB). The changes in precipitation extremes were derived from the most recent AFROCORDEX climate data base projection scenarios compared to the reference period (1971–2000). The climate change impacts on the hydrological extremes were evaluated using three conceptual hydrological models: GR4 J, HBV, and HMETS; and two objective functions: NSE and LogNSE. These hydrological models are calibrated and validated in the periods 1971–2000 and 2001–2010, respectively. The results indicate that the wet/dry spell will significantly decrease/increase due to climate change in some sites of the region, while in others, there is increase/decrease in wet/dry spell but not significantly, respectively. The extreme river flow will be less attenuated and more variable in terms of magnitude, and more irregular in terms of seasonal occurrence than at present. Low flows are projected to increase most prominently for lowland sites, due to the combined effects of projected decreases in Belg and Bega precipitation, and projected increases in evapotranspiration that will reduce residual soil moisture in Bega and Belg seasons.

Sign in / Sign up

Export Citation Format

Share Document