جستجوی مقالات مرتبط با کلیدواژه « : climate change » در نشریات گروه « آب و خاک »

Evapotranspiration variations (ET0) were investigated and analyzed using Minitab16 software for the 2010-2019 period using the Nizab system's data in Yazd province, and then ET0 was predicted until 2027. Based on the results, the increase of ET0 in cities of Yazd province was affected by the enhancement in wind speed and weather temperature, and the decrease in relative humidity from 2010 to 2019. To determine the appropriate model, Ardakan, Abarkooh, and Taft cities were selected as a representative in each climatic group, and ET0 data for the years 2010 to 2015 were considered as the input data of the software and ET0 data for the years from 2016 to 2019 were used to validate the determined model. The prediction of the determined models showed an increasing trend of ET0 for cold seasons in Ardakan and Abarkoh by 2027. Also, the model prediction showed a decreasing trend of ET0 for hot seasons in Taft by 2027. Also, the ET0 will not change significantly in cold seasons. In Abarkoh and Ardakan cities, autumn-spring crops such as wheat and in Taft city, spring-summer crops such as sunflower will be more affected by ET0 variations.

Nowadays, the world has different features than in the past, including intense and competitive changes, low adaptability, complexities, and uncertainties. The agricultural sector, as a major food producer worldwide, is not exempt from these traits, and, according to scientific reports and predictions, these changes are expected to become more prominent and challenging by 2050. In addition to the instability and restriction of main agriculture resources (water and soil), which can be seen in most parts of the world, other issues such as population growth and aging, rural-to-urban migration, declining willingness to work in agriculture, paradigm shift in food supply and demand, and most importantly climate change, have create serious obstacles in agriculture and food security governance of human societies. On the other hand, the technical and hidden aspects of these factors, as well as their entanglements and interactions, have made it more difficult to investigation. It is quite obvious that to overcome this complex and competitive environment, it is essential for countries to utilize efficient tools and methods, taking into account their own developmental conditions, by adopting an interactive approach at national and international levels, they must prioritize the formulation and implementation of strategic programs to enhance resilience and adaptability within their sustainable development policies. One such method that has gained attention in recent decades is futures studies based on the analysis of megatrends, which, through logical data analysis, provide a clearer picture of future priorities, strengths, and weaknesses for policymakers and statesmen. Given that Iran is also among the vulnerable countries against climate change impacts, the changing trend and predictions of the most significant factors affecting water, soil, and food have been evaluated, and while comparing Iran's situation globally, the necessity of serious attention and national resolve to confront these conditions has been emphasized.Studying of the effective trends in the agricultural, especially "climate changes" and "competition for production resources", shows that the emergence and intensification of conditions are quite evident, and despite of the expected unknown progress in the future, planning and implementation of actions based on "Mitigation" and "Adaptation" approaches are undeniable. Since Iran is located in the arid and semi-arid region of the world, it has always faced the negative effects of climate change, especially in terms of quantitative and qualitative characteristics of water resources, and considering that more than 93% of food production in Iran is dependent on irrigated croplands, this issue becomes even more important. Although in the country's Seventh Development Plan, the climate change issue is not considered enough, it is necessary to develop a comprehensive plan compatible with country conditions as a national agenda at the parliament and government level, as well as formation of a national working group consisting of responsible bodies, to implementation of appropriate action based on priorities. Of course, it is necessary that for each topic, the relevant government body should be adopt effective policies, for example, in population and urbanization issues, can be relatively managed through the implementation of incentive programs. Of course, the implementation of large-scale projects like this, will definitely not be realized without the participation and presence of the people, and therefore, one of the important priorities in the current conditions is focusing and preparing comprehensive plan in order to educate and improve public awareness, especially among the young generation, farmers, experts and Even managers. Also, in order to move on the path of sustainable development of the country in the field of water and soil, it is suggested that the following programs and approaches be emphasized and paid attention to:• Conducting of water resources management, especially underground water resources, by implementing watershed plans, flood control, optimal use of green water and water recycling projects.• Improving the productivity and efficiency of irrigation by using modern irrigation methods and using smart irrigation technologies and precision agriculture.• Modifying croping patterns according to the climatic conditions and reducing dependence on climate-sensitive products through plant biotechnology approaches.• Emphasis on the government's support policies for the agricultural sector with the priority of mechanized agricultural projects with high levels and productivity, such as agricultural settlements and revitalization of production hubs.• Development of international cooperation and exchange of experiences with specialized organizations and other countries that work in the field of agriculture and climate change.Fortunately, after establishment of the Global Soil Partnership Program or GSP, in the FAO, valuable actions and activities related to various aspects of sustainable soil management began with the cooperation of countries. Iran joined this program in 2016 and has had several joint programs in the fields of training, soil governance, awareness raising, managing salt affected soils, organizing soil laboratories network, increasing soil organic matter, soil studies, etc. with this international institution. And it is necessary to consider more arrangements for the maximum use of significant capacities with this global program.

Climate change, including drought, is an important threat to sustainable development. Entrepreneurial businesses are undeniable due to their acceptance and adaptation to environmental changes to respond to critical conditions. This research has been done with the aim of "analyzing the responses of entrepreneurs to the water crisis". In addition to identifying the answers, the effects of the water crisis on entrepreneurs and the consequences of the entrepreneurs' actions on the business performance were identified. In terms of results, this research is practical and of a qualitative type of case study. The research community is entrepreneurial businesses in the three provinces of Fars, Hormozgan, and Isfahan and the field of activity: agriculture, food products, tourism, mineral and industrial materials, and animal husbandry that were affected by the water crisis. Purposeful sampling method was used and data collection was done through in-depth and semi-structured interviews between February and March of 2022, which reached theoretical saturation after conducting 13 interviews. Data analysis was done by qualitative content analysis. The findings showed that the water crisis had an impact on two stages of the business value chain, i.e. "supply chain" and "production chain". Supply chain impacts include impacts on water resources and raw materials, and production impacts include impacts on products, process, assets, and production factors. The results indicate that entrepreneurs have reacted to these effects with three strategies, diversification, cooperation contracts, and processes modification. It was also found that the response of entrepreneurs to the water crisis has positive and negative effects on aspects of the company's performance (operational performance, financial performance, social performance, environmental performance).

Critical to human survival, water resources, including groundwater and particularly rivers, are under threat from anthropogenic pollution. The major Kashafrud River, located in northeastern Iran, is a seasonal watercourse currently encountering numerous challenges. At present, a stretch of this historic river (Parkandabad to the basin's exit) carries wastewater, comprising industrial, urban, agricultural, and even livestock effluents, transforming it into a conduit for sewage. This study reviews existing research on the challenges faced by the Kashafrud River, including pollution, climate change, and its impacts, as well as reduced runoff and drought. It outlines the crisis afflicting the river and then explores solutions to mitigate the current conditions. This research process involved reviewing previous studies on the challenges of Kashafrud, conducting field visits, engaging in discussions with local residents, and validating these findings through consultation with regional water experts responsible for overseeing this water course. Research indicates that there has been a limited focus on the pollution issue in Kashafrud, underscoring the evident necessity for comprehensive scientific inquiry aimed at presenting suitable solutions to tackle river contamination. In conclusion, through analyzing solutions proposed in previous studies and summarizing their strengths and weaknesses, 13 practical solutions were presented to provide the most effective strategies for addressing the challenges of this significant river.

Climate change phenomenon is one of the most important global challenges for mankind in providing sufficient and healthy food for the ever-increasing world population. The leading factors of climate change, such as increasing temperature, changing precipitation patterns, and increasing the frequency and intensity of weather events, affect soil characteristics, especially in the ecosystems of arid and semi-arid regions. These changes can directly affect the growth and production of crops. The amount of soil organic matter is one of the most important indicators of soil quality and health, which affects many physical, chemical and biological characteristics of soil and is directly and indirectly affected by climatic factors such as temperature and rainfall. On the other hand, the balance of input and output of organic carbon to the soil is effective on the amount of carbon dioxide in the atmosphere and thus on global warming and the climate change phenomenon. The results of many forecasts show that in arid and semi-arid regions, climate change will lead to an increase in temperature and a decrease in rainfall. Therefore, considering that the amount of organic matter in the soil decreases with the increase in temperature and decrease in humidity, it seems that the phenomenon of climate change will have adverse effects on the amount of soil organic matter and biological activity, and then on the production of crops in arid and semi-arid regions. Therefore, it is very important to use the necessary solutions to mitigate these adverse effects and adapt to the upcoming conditions. Mitigation refers to methods that lead to the reduction of greenhouse gas emissions, especially carbon dioxide; But the goal of adaptation is to mitigate the inevitable effects of climate change. Based on the results of various publications, compliance with the principles of the conservation agriculture system is considered one of the most important mitigation and adaptation solutions in dealing with the consequences of climate change in arid and semi-arid regions. Due to the fact that the climate change phenomenon is an inevitable event and its adverse effects and consequences in human life are felt more and more intense day by day, it is necessary for the management of soil resources to have the necessary foresight regarding the results of this phenomenon on the quality of the soil and the potential of producing agricultural products, especially in Arid and semi-arid areas should be considered.

Global warming threatens human survival in today's scenario; and has become an environmental challenge. The climate data shows the warming trend in many parts of the world, which has led to a wide range of climate effects such as reduced precipitation, drought, and the occurrence of extreme events. The increasing vulnerability of many urban areas, especially in developing countries, has been one of the main concerns of life. Therefore, examining the risk of risks caused by global warming on a national and local scale is a fundamental step to increase the readiness of urban areas to reduce current and future risks caused by climate change. Droughts have effects on vegetation, soil and freshwater quality, and etc., and are a serious ecological problem around the world, its impact on crops and water availability for humans can jeopardize human life. Although drought has always been common, the drought risk has become increasingly prominent because of the climatic warming that has occurred during the past century. Therefore, these effects of are noticeable in all climates, and Iran, having a dry and semi-arid climate, is one of the countries that is always at risk of drought, and this causes great economic damage to the country every year.  in addition to this, the review of the history and climatic texts shows that the importance of the effects of climatic elements (rainfall and temperature) on the drought situation of the region in the coming period is essential. Until now, the study of global warming in terms of increasing the risk of drought using the sixth report and new climate data has not been studied in Tehran province. So this study aims to investigate the effects of climate change on increasing the risk of drought in Tehran province.

This research, First, the parameters (temperature and precipitation) for the synoptic stations (Abali, Shemiran, Mehrabad) for the period (1988-2020) were received from the Tehran Meteorological Organization. To projection in the future, down-scaling methods (SDSM-DC model) and The Mann-Kendall test were used to investigate the changes in temperature and precipitation. Climatic parameters change in space and time scale for many reasons. that these changes should be checked based on observations and statistical methods. Rainfall is one of those climate parameters that is not normal, and methods such as Menn-Kendall should be used to deal with such conditions; For this purpose, using Macro Excel, the value of age slope and Z statistic was calculated in the period (1988-2020) for the stations (Mehrabad, Shemiran and Abali) to investigate the trend of precipitation and temperature from the past to the present at a confidence level of 95-99% computed. In the following NetCDF data together with CanESM5 predictors from the base period (1979-2014) according to the most recent SSP release scenarios of the IPCC 6th Report were obtained from the Canadian Climate Change website. Among them, only Mehrabad station had a complete basic period compared to other stations, it was chosen as the selected station in Tehran. Drought indices are used as an index to track and quantify drought, this research is SPI index with DIC software has been used to evaluate the drought. in this index Precipitation, which has been one of its main components, whose output and results are more consistent with reality.

The results using the Mann-Kendall test showed that the examination of temperature changes in the stations (Mehrabad, Shemiran, Abali) was an increasing trend. Rainfall in most months of the year is a stable trend, only jumps are observed which can be justified by the increase in the frequency of rainfall. In the simulation with the CanESM5 model under the SSP5 scenario at Mehrabad station, the highest temperature was assigned to July and the highest rainfall will be in March. in this research, The drought survey showed that Mehrabad station experienced severe drought only during 1989-1993, while the duration of the drought period was longer in Abali and Shemiran stations and both of them faced very severe drought in 2014. in addition, this Investigation of three stations with a common period of 32 years in Tehran shows that Tehran has overcome the drought situation in recent years; But most of the time, the region may be in close to normal climatic conditions. But the risk of dry to very dry conditions will be very close. On the other, the results confirmed that drought depends on both rainfall and temperature.

As drought depends on both precipitation and temperature, The more the drought is accompanied by the trend of increasing temperature, decreasing precipitation, and the prediction of climate models, the more likely it is that climate change will occur due to global warming. As a result, the temperature of Tehran will increase. And while the rainfall is decreasing, it will be fluctuating and torrential. so In the future, Tehran's climate will have more fluctuations in rainfall and will be warmer than the current conditions. In addition, rains will occur more randomly but with more intensity. Tehran has had a drought in recent years, but most of the time the region has been in near-normal climatic conditions, but is the risk of dry and very dry conditions. This factor will create environmental challenges in the future. In addition to this, it is necessary to have a plan for climate risk management in the future due to the new climate of Tehran, which is prone to drought.

Climate change is one of the greatest challenges of our time to achieve sustainable development. The dangers of global warming and climate change can be recognised and planned for, so efforts should be made to identify the consequences and methods of adaptation to reduce their impact, as trees and plants are sensitive to climate change, heat and moisture stress, and forest ecosystems are affected by these changes. Climate change is one of the greatest challenges of our time to achieve sustainable development. The threats of global warming and climate change can be identified and planned for, so efforts should be made to identify the consequences and methods of adaptation and reduce their impacts because the sensitivity of trees and plants to climate change, heat and moisture stress, forest ecosystems are affected by these changes. Forest degradation due to climate change is a global phenomenon affecting many tree species. One of the major challenges to Iran's natural resources is the degradation of oak forests. The increase in temperature in recent years has lengthened the growing season of Iranian oak, and due to the lack of rainfall, the intensity of water stress on this forest species has increased. Understanding the extent of climate change in the Zagros ecosystem based on standard indicators that show climate change can help managers and planners take action to adapt to conservation and restoration conditions.

In this study, based on the standard indicators established and updated by the World Meteorological Organization, the occurrence of climate change in six sites monitoring the decline of oak trees in Ilam Province, including Sarabeleh, Mala Siah and Dalab Strait, was detected in both north and south directions. The trend slope line, trend slope error and trend significance of the indices in the statistical range P value=0.05 were calculated using ClimPACT software in R program environment. The characteristics of heat, cold, combined, and precipitation indices such as day, number of occurrences, and continuity of the index in the nearest synoptic station to each site were identified, and daily data of minimum temperature, maximum temperature, and precipitation parameters were used between 1987 and 2019. The variations of each index were plotted and analyzed as graphs in the R software environment. Accordingly, the trend slope and significant indices affecting heat stress (hot temperature indices and cold-temperature indices) and water stress were calculated with the software ClimPACT in the R programme environment.

The results of the trend and significance of thermal indicators for climate change detection showed that of the 16 heat indices studied, in Ivan station, 11 indicators showed a significant trend of about 70% and in Ilam 9 indicators showed a significant trend of about 56%.The heat-based temperature indices, especially those based on maximum temperatures, showed a significant change towards warming, while those based on minimum temperatures showed no significant trend. The study of heat waves showed that the northern and northwestern regions of the province were subjected to several periods of heat waves, which occurred with greater frequency and continuity in the northwestern part of the province (Malah Siah and Dolab Strait sites) than in the northern part (Sarab sites) of the province, confirming the emergence of high mountain regions as a result of climate change. Cold-based temperature indices of 8 studied indices in Ivan-e-Sorchrove station, 7 indices were above 87% and Ilam 3 was about 38% the trend was significantThe cold-based temperature indices in Ivan West station show a significant change in the direction of a decrease of frost and cold and their persistence and warming, and in Ilam station the decrease of cold and warming of air after 2008 indicates a decrease of cold and warming. The results of the trend and significance of the combined indices for climate change detection in Ivan West station were 100% and in Ilam station 50% showed significant trend. The combined indices confirm climate change in terms of increase in air temperature due to increase in growing season and increase in trend of change in maximum temperature. The study of the trend and significance of ten precipitation indices related to the frequency and intensity of heavy rainfall and the length of dry and wet periods showed only one index in Ivan-e-West station, which was about 10%. The station Ilam did not show significant changes in the precipitation index.

It can be concluded that zagros vegetative region in Ilam province has experienced severe thermal changes during 1987-2019 and climate change in the north of Zagros vegetative region is a type of temperature increase that has been extended to the northwestern regions of this region since 2008. The results show that in deterioration sites, in addition to increasing temperature, some precipitation has increased. Therefore, it can be said that the occurrence of climate change phenomenon causes increasing temperature, occurrence of floods, emergence of droughts and creating dust phenomenon, especially from neighboring countries and intensifying it in the country, all of these factors are the starting factors of the decline of Oak Trees in Ilam province. What seems to be important is to take necessary measures to prevent and mitigate the effects of climate change. These two measures can be effective and useful in reducing the effects of flood severity and risk. Therefore, managers and planners of forest ecosystems should have adaptive strategies to climate change in order to maintain and revive their executive plans so that Zagros can survive as a forest ecosystem. Although the occurrence of climate change phenomenon is one of the most important factors of drought and deterioration of Zagros forests, conservation and restoration of oak forest ecosystems can help reduce greenhouse gas emissions and climate change.

Analysis of the spatial and temporal trends of precipitation is pertinent for the future sustainable management of water resources. Urbanization and climate change affected local rainfall and intensity. As rainfall characteristics are often used to design urban drainage systems, so watershed modeling, and estimate of the flood properties, updating and reviewing rainfall characteristics is necessary. The Intensity-Duration-Frequency (IDF) curves are a suitable tool to estimate the threshold values of precipitation in different return periods. IDF curves should be prepared based on the long-term rainfall statistics in each region and can change under the influence of climate change. These curves which indicate the frequency and maximum intensity of annual rainfall in the different return periods are suitable tools for planning and managing the water resources. IDF curves are broadly used for different purposes, such as the design of flood control and diversion structures in the cities. The main purpose of this research is to investigate the effect of climate change on temperature, precipitation, and IDF curves in the different return periods in an arid environment.

In this research, the effect of climate change on IDF curves was investigated in Kashan City as a dry region. Kashan city with an area of 9647 km2 is located in the northern part of the Isfahan Province. In this study, RCP8.5, RCP4.5, and RCP2.6 scenarios (which are introduced as optimistic, intermediate, and pessimistic scenarios) reported in the fifth assessment report of the Intergovernmental Panel on Climate Change (IPCC), were used to predict the impacts of climate change on temperature and precipitation changes. Then, IDF curves were calculated evaluated, and compared for the basic (1993-2017) and future periods (2011-2070). To examine the impact of climate change on the rainfall intensity patterns, it is necessary to extract IDF curves in different climate conditions. Bell's method is a usual method for extraction of the IDF curves, which was promoted by Gharehman-Abkhezr in Iran. In this study, the latest promoted relationships developed were for the desert and southern regions (e.g;Nizar-Salfachgan, Kuhpayeh, Herat, and Jiroft basins in the central Provinces, Qom, Isfahan, Kerman, and Yazd) have been presented and used to extract IDF curves. To investigate the effects of climate change on IDF curves, first, the base period curves were extracted via rainfall data measured at the Kashan synoptic station. Then, using the new climate scenarios (RCP8.5, RCP4.5, and RCP2.6) and the output data of the LARS exponential microscale model, the IDF curves were extracted for different climate scenarios in the future (2011-2030), (2031-2050), and (2051-2070). Finally, the results of these curves were compared with the base period.

According to the results, for the base period, the precipitation and temperature data were predicated with an acceptable accuracy by the LARS model. The accuracy of the model has been higher in estimating the minimum and maximum temperature. the Nash and explanation coefficients for the maximum and minimum temperatures were 0.99 and 0.99, respectively. While, the explanatory and Nash coefficients for precipitation data were 0.95 and 0.93, respectively. Based on the results, the rainfall intensity will have fewer changes compared to the base period for long-term duration rainfall compared to short-duration rainfall (less than four hr. The maximum changes are related to rainfalls with a duration of less than one hour, whereas the minimum changes are predicted for 24- hr rainfalls. For all studied scenarios, a significant difference (P<0.05) was predicted between the average rainfall intensity of 0.17 to 24 hr in the region. As in the two-year return period and under the 2.6 scenario, rainfall intensity was increased from 10.75 to 30.54 mm hr-1 for the duration time of 0.17 hr.

An increase in air temperature, decrease in rainfall, change in the rainfall pattern, decrease in river discharge, and increase in sudden floods, followed by an increase in soil erosion, and a decrease in the amount of agricultural products are the results of climate change. Therefore, the long-term analysis and monitoring of climatic conditions can be very effective for crisis management caused by climate changes such as floods and droughts. Based on the results, the effect of climate change on the intensity of short-term rainfall is greater than long-term duration rainfall, as the intensity of short-term rainfall will increase more than long-term rainfalls.

Iran and Afghanistan have a long history of facing climate hazards, leading to extensive damages to life, the environment, and economies. This research conducted a comprehensive comparative analysis of their long-term climate conditions on a national scale.Future climate scenarios based on IPCC6AR were projected to understand climatic similarities between the two nations. The results showed that recent years experienced the highest average temperatures in both countries, with significant changes occurring between 1991 and 2020 within the past 80 years. Monthly average temperatures over the last 80, 50, and 30 years exhibited a consistent upward trend, with the last decade being the warmest. Regarding precipitation patterns, the research revealed significant distribution changes in the last 80 years, particularly during 1951-1980 and 1971-2000 in Iran and Afghanistan, respectively. The study also examined natural hazards statistics resulting from climate change, including event frequency and the number of affected individuals over the past 40 years in both countries. The research emphasized preserving and revitalizing wetlands as an effective triple strategy to address climate change impacts in both countries. Given their shared exposure to climate change, conserving and restoration the Hamoun wetlands is crucial. Additionally, involving third parties in international discussions about wetlands or climate change can help resolve disputes.In conclusion, this study highlights the importance of understanding historical climate conditions and potential future scenarios for Iran and Afghanistan.

Climate change has been a crucial environmental issue in recent years, with global warming, water crisis, and ecosystem changes drawing significant attention. Scientists have been developing various scenarios of greenhouse gas emissions to model future climate changes.Prior research has focused on forecasting rainfall using the fifth climate change report, with little attention to the future socioeconomic impacts. This study addresses monthly rainfall prediction for the Kermanshah synoptic station using data from the sixth climate change report, considering various social and economic scenarios.

The Kermanshah province, located in the western part of the country, spans 24.64 square kilometers, in Iran. It stretches between the latitudes of 33° 36' to 35° 15' north and the longitudes of 45° 24' to 48° 30' east. The Kermanshah synoptic station is situated at the coordinates of 34° 21 longitude and 47° 10 latitude.One challenge with using AOGCM model outputs in regional climate change studies is the mismatch in spatial scale between the model's computational cells and the study area. At the same time, regional studies need data at a resolution of 50 kilometers or less to assess the effects of climate change. The current study utilized the Delta Change Factor (DCF) method to reduce the scale of GCM model data. In CMIP6, models typically feature enhanced resolution and improved dynamic processes. The simulation of future climate changes has utilized the Shared Socioeconomic Pathways (SSP) scenarios. These scenarios, employed in CMIP6, forecast global socioeconomic changes until 2100. The study utilizes the SSP5_8.5, SSP2_4.5, and SSP1_2.6 scenarios.To assess model accuracy, RMSE (Root Mean Square Error) and NSH (Nash-Sutcliffe Efficiency)are used as indicators.

In this study, three climate models - CanESM5, MRI-ESM2-0, and MIROC6 - were utilized to forecast monthly rainfall variability in Kermanshah synoptic station for the sixth climate change report across three future periods: 2026-2050, 2051-2075, and 2076-2100 under SSP126, SSP245, and SSP585 scenarios. The comparison of the trend of monthly rainfall changes in the corrected data indicates that the MIROC6 model predicts the median for the Kermanshah region with the least error compared to the other two models.In all scenarios, there is a decreasing trend in monthly precipitation. The lowest amount of precipitation is related to the months (JUNE-JULY-AUGUST-SEPTEMBER), while the highest amount of precipitation occurs in the months (APRIL-MARCH-NOVEMBER) across the near future, mid-term, and far future. The average rainfall in the SSP126 scenario is predicted to be higher for the MIROC6 model than for the other two models shortly (2026-2050). In the mid-term future (2051-2075), the MIROC6 model predicts less rainfall than the other two models, and in the far future (2076-2100), the CanESM5 model predicts the highest average rainfall for April. In the SSP245 scenario, shortly (2026-2050), the MRI-ESM2-0 model predicts the highest amount of rainfall for November, and the rest of the values are similar. In the mid-term future (2051-2075), the predictions of the models are almost similar, and in the far future (2076-2100), the MIROC6 model predicts the highest average rainfall for March, the CanESM5 model predicts the highest average rainfall for April, and the MRI-ESM2-0 model predicts the highest average rainfall for November. In the SSP585 scenario, shortly (2026-2050), the MRI-ESM2-0 model predicts more rainfall than the other two models. In the mid-term future (2051-2075), the CanESM5 model predicts the highest amount of rainfall for November, and in the distant future (2076-2100), the MRI-ESM2-0 model predicts the highest amount of rainfall for November, while the CanESM5 model predicts approximately the highest average predicted rainfall.

The most significant changes in monthly rainfall are expected to occur after bias correction in the first period (2026-2050) in the MRI-ESM2-0 model scenarios. The MIROC6 and CanESM5 models show similar predicted rainfall changes. In the second period (2051-2075), the trend of monthly rainfall changes for all three scenarios is more similar. However, the MIROC6 and CanESM5 models under the SSP126 scenario have predicted greater increases in rainfall compared to the SSP245 and SSP585 scenarios of the MRI-ESM2-0 model during this historical period. The MRI-ESM2-0, MIROC6, and CanESM5 models are suitable for use in the study area after bias correction, based on the validation index values for all three scenarios and models. Nonetheless, there are differences in the accuracy of the models for examining various climate change parameters and different climate regions. For instance, the MIROC6 model exhibits the highest accuracy for predicting monthly rainfall, while the MRI-ESM2-0 model has the lowest accuracy. The accuracy of the MRI-ESM2-0 model for predicting monthly rainfall in this study area is lower, but its accuracy for other climate change parameters and different regions may yield different results. The comparison of observational data and historical scenario model data in the study area for predicting future monthly rainfall shows that the best models for the study area are MIROC6 and CanESM5.

Due to climate change and human activities, the quality and quantity of water have become the most important concern of most of the countries in the world. In addition, changes in land use and climate are known as two important and influential factors in discharge. In this research, four climate change models including HADGEM2-ES, GISS-E-R, CSIRO-M-K-3-6-0, and CNRM-CM5.0 under two extreme scenarios RCP2.6 and RCP8.5 were used as climate change scenarios in the future period of 2020-2050. The future land use scenario (2050) was prepared using the CA-Markov algorithm in IDRISI software using land use maps in 1983 and 2020. The SWAT model was calibrated to better simulate hydrological processes from 1984 to 2012 and validated from 2013 to 2019 and was used to evaluate the separate and combined effects of climate change and land use on discharge. The prediction of the climate change impact on discharge showed a decrease in most of the models under the two scenarios RCP2.6 and RCP8.5. The average maximum decrease and increase under the RCP2.6 scenario is 60 and 30 percent, respectively. This significant reduction is greater than that predicted under the RCP8.5 scenario. Examining the combined effects of climate and land use change revealed that the average decrease in discharge in the months of October, November, December, and January under two scenarios is 46.2 and 58%, respectively. The average increase in discharge is predicted to be 47% under the RCP8.5 in the months of April and May in the HadGEM2ES.

A lack of adaptive capacities for climate change prevents poor farmers from diversifying agricultural production. Climate change adaptation strategies can reduce the production risk relating to unforeseen climatic shocks and increase farmers’ food, income, and livelihood security. This paper investigates date palm farmers’ adaptive capacities to adapt climate change strategies to reduce the date production risk. The study collected 300 farm-level micro-data of date palm farmers with the direct cooperation. The survey was conducted during periods between July and September of 2022. Date palm farmers’ adaptive capacities were estimated quantitatively by categorizing the farmers as high, moderate, and low-level adapters to climate change adaptation strategies. In this study, a Cobb–Douglas production function was used to measure the effects of farmers’ adaptive capacities on date production. The obtained results show that farmers are moderately adaptive in terms of adaptation strategies on climate change and the degree of adaptation capacities. Agronomic practices such as the quantity of fertilizer used, the amount of labor, the farm’s size, and extension contacts have a substantial impact on date production. This study recommends that a farmer more significantly adjusts to adaptation strategies on climate change to reduce date production. These strategies will help farmers to reduce the risk and produce higher quality date fruit. Consequently, date palm farmers should facilitate better extension services and change the present agronomic practice to attain a higher adaptation status. It can be very clearly seen that low adaptability results in lower date yields

Determining the future climate situation by using climate models seems necessary to consider in the field of adaptation or reducing the adverse effects of climate change. In this research, the temporal trend of rainfall, minimum and maximum temperature in the four stations in the Qarasu basin and in addition to, investigated using Thiessen's interpolation method. Among the five models of the CMIP6, three models were selected as the best models and used for MME. Biass Correction was done with CMHyd software for scenarios SSP2-4.5 and SSP5-8.5 in periods 2026-2050, 2051-2075 and 2076-2100. The trend of variables in the base period (1990-2014) and future were investigated with Mann-Kendall test and sens slope. The results of analysis significant trends annual average maximum and minimum temperature of all stations and in catchment area according to SSP2.4-5 scenario in two near and middle future periods and for SSP5-8.5 scenario in all three future periods have a significant trend at the 99% level. In analysis significant trend seasonal rainfall according to SSP2.4-5 scenario in the summer season distant future all stations and in near future of the station area of Gorgan regional water company at the 95% level and for the SSP5-8.5 scenario only in the winter season in the distant future Ghafarhaji station has a significant trend at the 99% level. The future monthly rainfall in the catchment area according to scenario of SSP2.4-5 in August at the 99% probability level and SSP5-8.5 in March at the 95% probability level have a significant trend.

The quality of river water is of great importance due to the limited availability of freshwater resources and the increased demand for water in the drinking water, agriculture, and other sectors. Rivers are one of the sources of this water supply, which are exposed to indiscriminate discharge of industrial, agricultural and human wastewater without proper environmental considerations.The study area in this research is the Sardabrud River located in Mazandaran province. The required data for conducting the research were collected from three stations along the river throughout a hydrological year and analyzed. In this study, the Iranian River Water Quality Index for surface waters (IRWQIsc) and the National Sanitation Foundation Water Quality Index (NSFWQI) were used to evaluate the river water quality. Based on the results, the values of the IRWQIsc index varied between 92.12-30.42 and the NSFWQI index between 92.35-48.075, indicating very good quality in spring and bad quality in winter for IRWQIsc, and excellent quality in spring and bad quality in summer for the NSFWQI, respectively.. Among the most important factors polluting the water of this river along its course are the discharge of agricultural and human sewage into the middle and downstream reaches, land use changes, and climate changes - which have caused a decrease in water quality along the river's path.Using the obtained results and current understanding, measures can be taken to prevent these polluting sources from entering the river to improve its water quality.

Agriculture, especially rainfed agriculture, is one of the branches that is largely affected by the effects of climate change. The previous studies regarding the estimation of the length of the dry season wheat growth period in the country are mainly related to the length of the growth period of the past years or based on the growing degree day method, which is not very realistic. The purpose of this research is to estimate the length of the average growth period of rainfed wheat for the Tabriz Plain for the past 20 years (1993-2017) and the future conditions under the simulation of GCM models, for the next 50 years (1394-1444), using the meteorological parameters of temperature and rainfall. is. In the first step, the state of future conditions was evaluated under the GCM models of the sixth report of the Intergovernmental Panel on Climate Change (IPCC) and under the SSP1-2.6 and SSP5-8.6 scenarios, and then with the proposed method of the ecological zoning guidelines of the Food and Agriculture Organization of the United Nations (FAO), the length of the growth period of each period has been estimated and compared with each other. According to the FAO method, the length of the growth period is equivalent to the period of time when the rainfall is more than 50 percent of the potential evaporation and transpiration. It has been done. The results of comparing the length of the growth period of the base period and the state of future conditions under the simulation of GCM models showed that in the Tabriz Plain, the length of the wheat growth period has increased by an average of 16 days for the next 50 years, and the end of the growth period by an average of It will happen 12 days later.