Climate change impact on meteorological droughts in watershed scale (case study: southwestern Iran)

Drought is one of the major natural disasters in the world which has a lot of social and economic impacts. There are various factors that affect climate changes; the investigation of this incident is also sensitive. Climate scenarios of future climate change studies and investigation of efficient methods for investigating these events on drought should be assumed. This study intends to investigate climate change impacts on drought in Karoon3 watershed in the future. For this purpose, the atmospheric general circulation models (GCM) data under Intergovernmental Panel on Climate Change (IPCC) scenarios should be investigated. In this study, watershed drought under climate change impacts will be simulated in future periods (2011 to 2099). In this research standard precipitation index (SPI) was calculated using mean monthly precipitation data in Karoon3 watershed. SPI was calculated in 6, 12 and 24 months periods. Statistical analysis on daily precipitation and minimum and maximum daily temperature was performed. To determine the feasibility of future periods meteorological data production of LRAS-WG5 model, calibration and verification was performed for the base year (1980-2007). Meteorological data simulation for future periods under General Circulation Models and climate change IPCC scenarios was performed and then the drought status using SPI under climate change effects analyzed. Results showed that differences between monthly maximum and minimum temperature will decrease under climate change and spring precipitation shall increase while summer and autumn rainfall shall decrease. The most increase of precipitation will take place in winter and in December. Normal and wet SPI category is more frequent in B1 and A2 emissions scenarios than A1B. Wet years increases in the study area during 2011-2030 period and the more continuous drought years gradually increases during 2046-2065 period, the more severe and frequent drought will occur during the 2080-2099 period.

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An Improved Daily Weather Generator for the Assessment of Regional Climate Change Impacts

10.21203/rs.3.rs-320088/v1 ◽

2021 ◽

Author(s):

Mohammad Reza Khazaei ◽

Mehraveh Hasirchian ◽

Bagher Zahabiyoun

Keyword(s):

Climate Change ◽

General Circulation ◽

Regional Climate ◽

Low Frequency ◽

Climate Change Impacts ◽

Regional Climate Change ◽

General Circulation Models ◽

Weather Generator ◽

Weather Data ◽

Monthly Precipitation

Abstract Weather Generators (WGs) are one of the major downscaling tools for assessing regional climate change impacts. However, some deficiencies in the performance of WGs have limited their usage. This paper presents a method for correcting the low-frequency variability (LFV) of precipitation in the Improved Weather Generator (IWG) model. The method is based on bias correction in the monthly precipitation distribution of the generated daily series. The performance of the modified model was tested directly by comparing the statistics of generated and observed weather data for 14 stations, and also indirectly by comparing the characteristics of simulated stream-flows of a basin from the simulations run based on generated and observed weather data. The results showed that the method not only corrected the LFV of precipitation but also improved the reproduction of many other statistics. The provided IWG2 model can serve as a useful tool for the downscaling of General Circulation Models (GCMs) scenarios to assess regional climate change impacts, especially hydrological effects.

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Modeling the Impacts of Future Climate Change on Irrigation over China: Sensitivity to Adjusted Projections

Journal of Hydrometeorology ◽

10.1175/jhm-d-13-0182.1 ◽

2014 ◽

Vol 15 (5) ◽

pp. 2085-2103 ◽

Cited By ~ 18

Author(s):

Guoyong Leng ◽

Qiuhong Tang

Keyword(s):

Climate Change ◽

Climate Variability ◽

General Circulation ◽

Southern China ◽

Climate Change Impacts ◽

General Circulation Models ◽

Future Climate ◽

Future Climate Change ◽

Community Land Model ◽

The Impact

Abstract Because of the limitations of coarse-resolution general circulation models (GCMs), delta change (DC) methods are generally used to derive scenarios of future climate as inputs into impact models. In this paper, the impact of future climate change on irrigation was investigated over China using the Community Land Model, version 4 (CLM4), which was calibrated against observed irrigation water demand (IWD) at the provincial level. The results show large differences in projected changes of IWD variability, extremes, timing, and regional responses between the DC and bias-corrected (BC) methods. For example, 95th-percentile IWD increased by 62% in the BC method compared to only a 28% increase in the DC method. In addition, a shift of seasonal IWD peaks (averaged over the country) to one month later in the year was projected when using the BC method, whereas no evident changes were predicted when using the DC method. Furthermore, low-percentile runoff has larger impacts in the BC method compared with proportional changes in the DC method, indicating that hydrological droughts seem to be exacerbated by increased climate variability. The discrepancies between the two methods were potentially due to the inability of the DC method to capture the changes in precipitation variability. Therefore, the authors highlight the potential effects of climate variability and the sensitivity to the choice of particular strategy-adjusting climate projection in assessing climate change impacts on irrigation. Some caveats, however, should be placed around interpretation of simulated percentage changes for all of China since a large model bias was found in southern China.

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Projecting the Impact of Climate Change on Temperature, Precipitation, and Discharge in the Bago River Basin

Journal of Disaster Research ◽

10.20965/jdr.2020.p0324 ◽

2020 ◽

Vol 15 (3) ◽

pp. 324-334 ◽

Cited By ~ 1

Author(s):

Hnin Thiri Myo ◽

Win Win Zin ◽

Kyi Pyar Shwe ◽

Zin Mar Lar Tin San ◽

Akiyuki Kawasaki ◽

...

Keyword(s):

Climate Change ◽

River Basin ◽

General Circulation ◽

Meteorological Data ◽

Coupled Model ◽

General Circulation Models ◽

Monthly Precipitation ◽

Rcp Scenarios ◽

Impact Of Climate Change ◽

The Impact

Climate change affects both the temperature and precipitation, leading to changes in river runoff. The Bago River basin is one of the most important agricultural regions in the Ayeyarwady Delta of Myanmar, and this paper aims to evaluate the impact of climate change on it. Linear scaling was used as the bias-correction method for ten general circulation models (GCMs) participating in the fifth phase of the Coupled Model Intercomparison Project. Future climate scenarios are predicted for three 27-year periods: the near future (2020–2046), middle future (2047–2073), and far future (2074–2100) with a baseline period of (1981–2005) under two Representative Concentration Pathway (RCP) scenarios: RCP4.5 and RCP8.5 of the IPCC Assessment Report 5 (AR5). The Hydrologic Engineering Center-Hydrologic Modeling System model is used to predict future discharge changes for the Bago River considering future average precipitation for all three future periods. Among the GCMs used to simulate meteorological data in the Ayeyarwady Delta zone, the Model for Interdisciplinary Research on Climate-Earth System is the most suitable. It predicts that average monthly precipitation will fluctuate and that average annual precipitation will increase. Both average monthly and annual temperatures are expected to increase at the end of the 21st century under RCP4.5 and RCP8.5 scenarios. The simulation shows that the Bago River discharge will increase for all three future periods under both scenarios.

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Combined impact of Climate change and Land use on water quality in the mid-21st century: A modelling study for a highly industrialized stretch of Ganga River

10.5194/egusphere-egu21-795 ◽

2021 ◽

Author(s):

Sneha Santy ◽

Pradeep Mujumdar ◽

Govindasamy Bala

Keyword(s):

Climate Change ◽

Water Quality ◽

Land Use ◽

Land Cover ◽

General Circulation ◽

General Circulation Models ◽

Ganga River ◽

Quality Analysis ◽

Future Climate Change ◽

Land Use Land Cover

<p>High industrial discharge, excessive agricultural activities, untreated sewage disposal make the Kanpur region one of the most contaminated stretches of the Ganga river. This study analyses water quality for the combined future climate change and land use land cover scenarios for mid-century for a 238km long Kanpur stretch of Ganga river. Climate change projections from 21 General Circulation Models for the scenarios of RCP 4.5 and RCP 8.5 are considered and Land use Land Cover (LULC) projections are made with QGIS software. Streamflow and water temperature are modelled using the HEC-HMS model and a Water-Air temperature regression model, respectively. Water quality analysis is simulated using the QUAL2K model in terms of nine water quality parameters, dissolved oxygen, biochemical oxygen demand (BOD), ammonia nitrogen, nitrate nitrogen, total nitrogen, organic phosphorus, inorganic phosphorus, total phosphorus and faecal coliform. Climate change impact alone is projected to result in degraded water quality in the future. Combined climate change and LULC change may further degrade water quality, especially at the study area's critical locations. Our study will provide guidance to policymakers to safeguard the Ganga river from further pollution.</p>

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Impact of future climate change on water supply and irrigation demand in a small mediterranean catchment. Case study: Nebhana dam system, Tunisia

Journal of Water and Climate Change ◽

10.2166/wcc.2019.131 ◽

2019 ◽

Vol 11 (4) ◽

pp. 1724-1747 ◽

Cited By ~ 2

Author(s):

M. Allani ◽

R. Mezzi ◽

A. Zouabi ◽

R. Béji ◽

F. Joumade-Mansouri ◽

...

Keyword(s):

Climate Change ◽

Water Supply ◽

General Circulation ◽

General Circulation Models ◽

Future Climate ◽

Annual Rainfall ◽

Future Climate Change ◽

Cycle Duration ◽

Climate Change Scenarios ◽

Time Periods

Abstract This study evaluates the impacts of climate change on water supply and demand of the Nebhana dam system. Future climate change scenarios were obtained from five general circulation models (GCMs) of CMIP5 under RCP 4.5 and 8.5 emission scenarios for the time periods, 2021–2040, 2041–2060 and 2061–2080. Statistical downscaling was applied using LARS-WG. The GR2M hydrological model was calibrated, validated and used as input to the WEAP model to assess future water availability. Expected crop growth cycle lengths were estimated using a growing degree days model. By means of the WEAP-MABIA method, projected crop and irrigation water requirements were estimated. Results show an average increase in annual ETo of 6.1% and a decrease in annual rainfall of 11.4%, leading to a 24% decrease in inflow. Also, crops' growing cycles will decrease from 5.4% for wheat to 31% for citrus trees. The same tendency is observed for ETc. Concerning irrigation requirement, variations are more moderated depending on RCPs and time periods, and is explained by rainfall and crop cycle duration variations. As for demand and supply, results currently show that supply does not meet the system demand. Climate change could worsen the situation unless better planning of water surface use is done.

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Modelling the impacts of European emission and climate change scenarios on acid-sensitive catchments in Finland

Hydrology and Earth System Sciences ◽

10.5194/hess-12-449-2008 ◽

2008 ◽

Vol 12 (2) ◽

pp. 449-463 ◽

Cited By ~ 11

Author(s):

M. Posch ◽

J. Aherne ◽

M. Forsius ◽

S. Fronzek ◽

N. Veijalainen

Keyword(s):

Climate Change ◽

Surface Water ◽

Emission Reduction ◽

General Circulation ◽

General Circulation Models ◽

Chemical Recovery ◽

Climate Change Scenarios ◽

Intergovernmental Panel ◽

Sulphur Deposition ◽

Temperature And Precipitation

Abstract. The dynamic hydro-chemical Model of Acidification of Groundwater in Catchments (MAGIC) was used to predict the response of 163 Finnish lake catchments to future acidic deposition and climatic change scenarios. Future deposition was assumed to follow current European emission reduction policies and a scenario based on maximum (technologically) feasible reductions (MFR). Future climate (temperature and precipitation) was derived from the HadAM3 and ECHAM4/OPYC3 general circulation models under two global scenarios of the Intergovernmental Panel on Climate Change (IPCC: A2 and B2). The combinations resulting in the widest range of future changes were used for simulations, i.e., the A2 scenario results from ECHAM4/OPYC3 (highest predicted change) and B2 results from HadAM3 (lowest predicted change). Future scenarios for catchment runoff were obtained from the Finnish watershed simulation and forecasting system. The potential influence of future changes in surface water organic carbon concentrations was also explored using simple empirical relationships based on temperature and sulphate deposition. Surprisingly, current emission reduction policies hardly show any future recovery; however, significant chemical recovery of soil and surface water from acidification was predicted under the MFR emission scenario. The direct influence of climate change (temperate and precipitation) on recovery was negligible, as runoff hardly changed; greater precipitation is offset by increased evapotranspiration due to higher temperatures. However, two exploratory empirical DOC models indicated that changes in sulphur deposition or temperature could have a confounding influence on the recovery of surface waters from acidification, and that the corresponding increases in DOC concentrations may offset the recovery in pH due to reductions in acidifying depositions.

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Estimation of hydrological response to future climate change in a cold watershed

Journal of Water and Climate Change ◽

10.2166/wcc.2018.026 ◽

2018 ◽

Vol 10 (1) ◽

pp. 78-88 ◽

Cited By ~ 1

Author(s):

Jian Sha ◽

Zhong-Liang Wang ◽

Yue Zhao ◽

Yan-Xue Xu ◽

Xue Li

Keyword(s):

Climate Change ◽

General Circulation ◽

Water System ◽

Coupled Model ◽

Weather Conditions ◽

General Circulation Models ◽

Future Climate ◽

Future Climate Change ◽

Research Station ◽

Hydrological Process

Abstract The vulnerability of the natural water system in cold areas to future climate change is of great concern. A coupled model approach was applied in the headwater watershed area of Yalu River in the northeastern part of China to estimate the response of hydrological processes to future climate change with moderate data. The stochastic Long Ashton Research Station Weather Generator was used to downscale the results of general circulation models to generate synthetic daily weather series in the 2050s and 2080s under various projected scenarios, which were applied as input data of the Generalized Watershed Loading Functions hydrological model for future hydrological process estimations. The results showed that future wetter and hotter weather conditions would have positive impacts on the watershed runoff yields but negative impacts on the watershed groundwater flow yields. The freezing period in winter would be shortened with earlier snowmelt peaks in spring. These would result in less snow cover in winter and shift the monthly allocations of streamflow with more yields in March but less in April and May, which should be of great concern for future local management. The proposed approach of the coupled model application is effective and can be used in other similar areas.

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Integrated Assessment of Climate Change Impacts on Corn Yield in the U.S. Using a Crop Model

Transactions of the ASABE ◽

10.13031/trans.12314 ◽

2017 ◽

Vol 60 (6) ◽

pp. 2123-2136

Author(s):

Kenichi Tatsumi

Keyword(s):

Climate Change ◽

General Circulation ◽

Climate Change Impacts ◽

General Circulation Models ◽

Crop Model ◽

Corn Yield ◽

Negative Impacts ◽

Growing Conditions ◽

Almost All ◽

The U.S

Abstract. A detailed analysis was conducted of the effects of climate change and increased carbon dioxide (CO2) concentrations on corn yield in the U.S. with a crop model using outputs from multiple general circulation models (multi-GCMs). Corn yield was simulated for 1999-2010, for the 2050s (average for 2041-2060), and for the 2070s (average for 2061-2080) under the representative concentration pathway 8.5 (RCP8.5) climate scenario. Results indicated a shortening of the growing period (GP), decreased water use efficiency (WUE) in almost all regions, and increased evapotranspiration (ET) during GP in almost all regions except for the southern U.S. Using multi-GCMs, the simulations under the RCP8.5 scenario resulted in negative effects of climate change on yield in almost all regions during both future periods. Especially strong negative impacts were reported south of latitude 40° N due to less optimal growing conditions. On the other hand, there were relatively smaller negative impacts in high-latitude regions (approximately north of latitude 40° N) due to more optimal growing conditions because of larger temperature changes compared to low-latitude and mid-latitude regions. Higher CO2 concentrations have the potential to increase corn yield. CO2 effects resulted in an approximately 0.04% to 0.05% increase in yield per 1 ppm increase in CO2 concentration under the RCP8.5 scenario, but the negative impacts of increased temperatures fully outweighed the CO2-fertilization effects. Keywords: Climate change impacts, CO2 effects, Corn yield, Multiple GCMs, Uncertainty.

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How Well Do We Understand and Evaluate Climate Change Feedback Processes?

Journal of Climate ◽

10.1175/jcli3819.1 ◽

2006 ◽

Vol 19 (15) ◽

pp. 3445-3482 ◽

Cited By ~ 673

Author(s):

Sandrine Bony ◽

Robert Colman ◽

Vladimir M. Kattsov ◽

Richard P. Allan ◽

Christopher S. Bretherton ◽

...

Keyword(s):

Climate Change ◽

Climate Sensitivity ◽

General Circulation ◽

External Perturbation ◽

General Circulation Models ◽

Lapse Rate ◽

Climate Feedback ◽

Climate Feedbacks ◽

Intergovernmental Panel ◽

Global Estimates

Abstract Processes in the climate system that can either amplify or dampen the climate response to an external perturbation are referred to as climate feedbacks. Climate sensitivity estimates depend critically on radiative feedbacks associated with water vapor, lapse rate, clouds, snow, and sea ice, and global estimates of these feedbacks differ among general circulation models. By reviewing recent observational, numerical, and theoretical studies, this paper shows that there has been progress since the Third Assessment Report of the Intergovernmental Panel on Climate Change in (i) the understanding of the physical mechanisms involved in these feedbacks, (ii) the interpretation of intermodel differences in global estimates of these feedbacks, and (iii) the development of methodologies of evaluation of these feedbacks (or of some components) using observations. This suggests that continuing developments in climate feedback research will progressively help make it possible to constrain the GCMs’ range of climate feedbacks and climate sensitivity through an ensemble of diagnostics based on physical understanding and observations.

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Hydrological responses to climate change conditioned by historic alterations of land-use and water-use

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-8-7595-2011 ◽

2011 ◽

Vol 8 (4) ◽

pp. 7595-7620 ◽

Cited By ~ 3

Author(s):

J. Jarsjö ◽

S. M. Asokan ◽

C. Prieto ◽

A. Bring ◽

G. Destouni

Keyword(s):

Climate Change ◽

Water Loss ◽

Land Surface ◽

General Circulation ◽

General Circulation Models ◽

Future Climate ◽

Aral Sea ◽

Future Climate Change ◽

Hydrological Responses ◽

Irrigation Practices

Abstract. This paper quantifies and conditions expected hydrological responses in the Aral Sea Drainage Basin (ASDB; occupying 1.3 % of the earth's land surface), Central Asia, to multi-model projections of climate change in the region from 20 general circulation models (GCMs). The aim is to investigate how uncertainties of future climate change interact with the effects of historic human re-distributions of water for land irrigation to influence future water fluxes and water resources. So far, historic irrigation changes have greatly amplified water losses by evapotranspiration (ET) in the ASDB, whereas the 20th century climate change has not much affected the regional net water loss to the atmosphere. Projected future climate change (for the period 2010–2039) however is here calculated to considerably increase the net water loss to the atmosphere. Furthermore, the ET response strength to any future temperature change will be further increased by maintained (or increased) irrigation practices. With such irrigation practices, the river runoff is likely to decrease to near-total depletion, with risk for cascading ecological regime shifts in aquatic ecosystems downstream of irrigated land areas. Without irrigation, the agricultural areas of the principal Syr Darya river basin could sustain a 50 % higher temperature increase (of 2.3 °C instead of the projected 1.5 °C until 2010–2039) before yielding the same consumptive ET increase and associated R decrease as with the present irrigation practices.

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