The Impact of Climate Change on Climate Variables and Meteorological Drought Using the climate change Toolkit (CCT) in the Karkheh River Basin, Iran (original) (raw)

Impact of climate change on droughts: a case study of the Zard River Basin in Iran

Water Practice & Technology

In this research a SWAT model was assembled and used to evaluate the effects of climate change on runoff and drought in a semi-arid basin in Iran. The SWAT model showed good performance in the simulation of runoff. Eleven General Circulation Models (GCMs) under Representative Concentration Pathway 4.5 and Representative concentration Pathway 8.5 (RCP45 and RCP85) scenarios, and the period 2022-2041 was selected to investigate future projections. It was predicted that under all of the scenarios, runoff will decrease significantly. Annual rates showed that runoff will fall to 7.73 m3/s (11.6% decreased) and 6.78 m3/s (22.5% decreased) under RCP45 and RCP85 from 8.75 m3/s during next 20 years in this basin, respectively. In this research, the meteorological and hydrological droughts were estimated using SPI and SDI indices, respectively. By coupling of climate change scenarios and SWAT models it was found that the severity of droughts in the future will be far greater than has ever hap...

Quantitative assessment and prediction of drought under climate change impact in Birjand region, Iran

Drought as a natural hazard, causes high amount of damages to farmers, government and different people in societies. Protecting against this phenomena can lead to decline the damage. In order to reach this aim, in the present study, A1 emission scenario, ECHO-G model and LARS-WG (LARS-Weather Generator) statistical downscaling method are used for downscaling parameters of minimum and maximum temperature and rainfall. Using two drought indices, SPI (Standardized Precipitation Index) and RDI (Reconnaissance Drought Index), the uncertainty of generated data is computed to assess the model abilities. The drought indices were estimated and assessed in different scales. Then, the frequency analysis of maximum and average characteristics of drought severity in different return periods were performed. The results indicated that SPI and RDI have similar trends in recognizing classified range of drought severity. Of course, RDI index identified and assessed drought with high intensity. The frequency analysis in this station showed that the basin had strong sensitivity to these characteristics in different return periods.

Determination of Crisis Areas of Precipitation in Iran for Period of 2021-2040 by Climate Change

University of Tehran, Faculty of Agricultural Technology, University College of Agriculture & Natural Resources, 2023

The climate change effect on future precipitation (2040-2021) of Iran is investigated in this study. For this purpose, the results of three general circulation models (GCM) named GFDL-ESM2M, HadGEM2-ES and IPSL-CM5A-LR were analyzed for two scenarios of greenhouse gas emissions RCP2.6 and RCP8.5. CCT model and daily precipitation data of the base period (1986-2019) were used to downscale and bias correction of future daily precipitation data. According to the annual results, the weighted average of annual precipitation of rain gauges due to all scenarios except RCP8.5 in the IPSL-CM5A-LR model was increasing. The weighted average of seasonal precipitation in winter increased in all of the studied climate change conditions, but in other seasons the amount of precipitation decreased or increased. The highest increase in the weighted average of seasonal precipitation was in winter due to the RCP2.6 scenario and GFDL-ESM2M model (23 mm). The highest decrease in the weighted average of seasonal precipitation was in autumn due to the RSP8.5 scenario and IPSL-CM5A-LR (10.5 mm). Slight changes in mean precipitation, on the other hand, a sharp decrease in minimum precipitation (446 mm due to G3S4) and a sharp increase in maximum precipitation (233 mm due to G2S1), indicate the occurrence of severe extreme events (drought and flood) in the future.

Meteorological Drought Analysis Using Global Climate Model and Drought Indicators in West of Iran

2021

Climate change and global warming impact the frequency of droughts and supply systems. Therefore, it is necessary to conduct appropriate studies to evaluate the impact of climate change on weather patterns and drought. For this purpose, data from 6 synoptic stations located in the wet and temperate areas in the Zagros region in western Iran were used to construct four general atmospheric models including BCC-CSM1, CANESM2, HADGEM2-ES, NORESM1-M under representative concentration pathways (RCPs) 2.6, 4.5, and 8.5, for three future periods (2010-2039), (2040-2069) and (2070-2099). Then, spatio-temporal variations of drought severity and frequency were studied in the study area using SPI and SPEI indices in different periods up to 2100. The results showed the spatial extent of areas classified as extremely dry will increase by 47.9% in the first period compared to the base period. In the second and third periods, however, the severely dry class covers more area. Analysis of SPEI showed...

Investigation of Climate Change Effect on Drought Characteristics in the Future Period using the HadCM3 model (Case Study: Khoy Station, Northwest of Iran)

Desert, 2017

Investigation of drought event has a great importance in the natural resources and water resources management and planning. In this research, the effect of the climate change on drought characteristics in Khoy station was investigated using the HadCM3 model under B2 scenario. The statistical downscaling was executed using SDSM 4.2.9 and observed daily precipitation, observed predictors and large-scale predictors derived from the HadCM3 model. Afterwards the SPI was calculated for different time scales of 3, 12, 24, 48 months in the observed period of 1977-2006 and also three periods of 2007-2036, 2037-2066 and 2067-2096. The results show that the mean annual precipitation will decrease in the future periods, in the manner that the fourth and second periods respectively with the depletion of 48 mm (17%) and 34 mm (12%) than the observed period have maximum and minimum rate of the depletion. The results also show that the drought occurrence with more intensity, duration and frequency ...

Drought occurrence under future climate change scenarios in the Zard River basin, Iran

Water Science & Technology: Water Supply, 2020

Global warming affected by human activities causes changes in the regime of rivers. Rivers are one of the most vital sources that supply fresh water. Therefore, management, planning, and proper use of rivers will be crucial for future climate change conditions. This study investigated the monitoring of hydrological drought in a future period to examine the impact of climate change on the discharging flow of the Zard River basin in Iran. Zard River is an important supplier of fresh and agricultural water in a vast area of Khuzestan province in Iran. A continuous rainfall-runoff model based on Soil Moisture Accounting (SMA) algorithm was applied to simulate the discharge flow under 10 scenarios (obtained from LARS-WG.6 software) of future climate change. Then, the Stream-flow Drought Index (SDI) and the Standard Precipitation Index (SPI) were calculated for each climate change scenario for the future period (2041-2060). The results of the meteorological drought assessment showed that near normal and moderate droughts had higher proportions among other drought conditions. Moreover, the hydrological drought assessment showed the occurrence of two new droughts (severe and extreme) conditions for the future period (2041-2060) that has never happened in the past (1997-2016).

Assessing the Impact of Climate Changes on Hydrological Drought Based on Reservoir Performance Indices (Case Study: ZayandehRud River Basin, Iran)

Water Resources Management, 2017

We investigated the potential impacts of climate changes on hydrological drought of the Zayandehrud basin in Iran. The meteorological data was simulated using the LARS-WG model by output downscaling of HADCM3, INCM3 and NCCCSM from 2011 to 2040 under A1B, A2 and B1 scenarios. In order to estimate the runoff of the basin, the IHACRES model was calibrated and validated by data obtained from the Koohrang station during 1987-2007. The runoff was calculated for 2011-2040 period based on the mean of downscaling values in the IHACRES model. Then, the impact of climate changes on hydrological drought was studied by a probabilistic approach and MSUI index. The results revealed a drastic reduction in normal levels and also a significant increase in moderate, severe, and very severe drought levels in the future compared to the base period. The MSUI index represents a 42.32% reduction in the normal level based on the HADCM3 model under A1B scenario as well as an 86.8%increasein the severe drought. Furthermore, the HADCM3 model using the probabilistic approach showed a 73% reduction under the A2 scenario for normal condition and an increase of 20% for severe drought.

Application of standardised precipitation index for predicting meteorological drought intensity in Beheshtabad watershed, central Iran

International Journal of Hydrology Science and Technology, 2013

Demand for water is on the rise everywhere in the world, particularly in arid and semiarid countries including Iran. Arid and semiarid regions suffer from droughts. The goal of this study is to predict the standardised precipitation index (SPI) for future drought intensity in Beheshtabad watershed, Karun basin, which is located in central Iran. Daily climate series were produced using the recorded data of Shahrekord gaging station of a reference period (1961-1990). Hadley Center Climate Model 3 general circulation model (GCM) with one greenhouse gas emission scenario (A2) has been used to construct daily climate precipitation time series over three future periods (2010-2039, 2040-2069 and 2070-2099). The statistical downscaling model (SDSM) was used to downscale GCM output. SPI for three 30-year future time series was determined on 3, 6, 9 and 12 months. The results indicate that at short time scales, the drought series have a high frequency of drought and short duration instead the SPI values of longer time scale had an extended range with low frequency of drought. The results indicated that the severity of droughts do not solely depend on the values of drought index and also depends on duration. The results show that an increase in duration and magnitude of droughts in the third future period is more than the second and initial future periods.

Prediction of Climate Change Induced Temperature & Precipitation: The Case of Iran

Sustainability, 2017

Concern about the effects of climatic change on numerous aspects of human life in general and on agricultural production in particular is growing. The utility of HadCM3 as a tool in climate change predictions in cross cultural studies is scarce. Therefore, this study sought to investigate and predict climate change induced temperature and precipitation in Iran. The calibration and validation using the HadCM3 was performed during 1961-2001, using daily temperatures and precipitation. The data on temperature and precipitation from 1961 to 1990 were used for calibration, and, for model validation, data from 1991 to 2001 were used. Moreover, in order to downscale general circulation models to station scales, SDSM version 4.2 was utilized. The least difference between observed data and simulation data during calibration and validation showed that the parameter was precisely modeled for most of the year. Simulation under the A2 scenario was performed for three time periods (2020, 2050, and 2080). According to our simulated model, precipitation showed a decreasing trend whereas temperature showed an increasing trend. The result of this research paper makes a significant contribution to climate smart agriculture in Iran. For example, rural development practitioners can devise effective policies and programs in order to reduce the vulnerability of local communities to climate change impacts. Moreover, the result of this study can be used as an optimal model for land allocation in agriculture. Moreover, a shortage of rainfall and decreased temperatures also have implications for agricultural land allocation.

Investigation of the effects of climate change on hydrological drought and pattern detection for severe climatic conditions using CCT and SWAT models in the semi-arid region - Case study: Karkheh river basin

Drought causes an imbalance in the hydrological condition of the area. Climate change is exacerbating this situation. In this study, the hydrological drought under the influence of climate change in Karkheh river basin was investigated using the SRI index. For this purpose, the Soil and Water Assessment Tool model was calibrated (1990 to 2009) and validated (2010 to 2018) using data from 17 meteorological stations and 11 hydrometric stations. Then, based on the runoff simulated by the model, the index in all sub-basins for the base period (1990 to 2018) is calculated. By introducing the microscale results of 5 climate models in the Climate Change Toolkit program under RCP 2.6 and RCP8.5 scenarios to the SWAT model, the SRI index was simulated for the near future (2043 to 2071) and the distant future (2072 to 2100); and its intensity, duration and frequency were compared with the baseline period. The results show that hydrological drought will decrease in the near future for both sce...