farshad soleimani sardoo

Blowing dust is one of the most common natural phenomena in arid and semi-arid regions, which causes a lot of damage every time it occurs. This phenomenon is introduced as a natural hazard in terms of negative effects in natural and human-managed ecosystems, and it is one of the most important problems of societies in arid and semi-arid regions. This research was simulated using the WRF-Chem model and GOCART scheme in the Jazmurian basin in southeast Iran to investigate and analyze this phenomenon. The results showed that the numerical simulation of the dust storm using the WRF-Chem model simulated surface dust concentration values UTC18 on December 17, 2016, in the south of Sistan and Baluchistan province and Hormozgan province were higher than 2500 µg/m3, and more than 2000 µg/m3 in the central areas of Jazmurian region. To prevent destructive dust storms and reduce the emission of dust in this region, international protocols are needed for the correction and rehabilitation of degraded lands and activities to prevent desertification to stabilize degraded soils.

Climate change is one of the most important challenges of this century. The consequences of these changes and how to adapt to them as well as reducing the causes of climate change are important points of this phenomenon. Currently, there is scientific and definite evidence about the warming of the earth and the unprecedented increase in temperature on the surface of the earth and the atmosphere caused by it is a human activity, it is a proof of this. The most important parameters affecting the phenomenon of climate change are precipitation and temperature.

The CanESM2 model was used to predict the climatic parameters of temperature, precipitation and wind speed under the RCP to predict the climate change in Karaj station.

The results showed that the average rainfall in the Karaj station was 96 mm in the historical period which is according to the scenarios RCP2.6, RCP4.5 and RCP 8.5 will decrease in the near future (2060 - 2030) and 62 % in the near future (2060 - 2030) and 81 % in the future (2070 - 2099) than the observed period (1985 - 2017). The results of the simulation of the average temperature according to RCP2.6, RCP4.5 and RCP8.5 scenarios showed that the average temperature in the future period is close to 0.53, 0.17 and 0.19% compared to the observation period (15.81 degrees Celsius) will decrease, while in the future period (2070-2100) under the RCP2.6 scenario, it will decrease by 1.11 percent and according to the RCP4.5 and RCP8.5 scenarios, it will increase by 0.39 and 2.13 percent. The average simulated wind speed showed that the wind speed was 27.89, 25.03 and 24.55% in the period from 2030 to 2060 and 34.16, 25.37 and 23.84% in the period from 207 to 2100 under the RCP scenarios compared to the value observed (2.41 m/s) will increase.

The evaluation results of CanESM2 model in this study can be considered as an acceptable statistical result to investigate the changes of climatic parameters. Observing the pattern of consumption and optimal use of water resources as well as preventing the increase of greenhouse gases can control the trend of increasing temperature and decreasing rainfall.

Watershed projects are one of the most important executive activities to improve and restore pastures and watersheds. These activities are carried out in the context of the restoration of watersheds in order to increase the power of ecosystems and to increase the production and services of ecosystems. Increased in vegetation leads to an increase in carbon sequestration in the soil. Therefore, the evaluation of the effectiveness of watershed projects can therefore justify the allocation of the necessary funds for studies and field activities by policy makers and planners. This study aimed to investigate the effectiveness of watershed management projects in the Hossein Abad Jiroft area in terms of vegetation management. Landsat TM+ and Sentinel 2A satellite images were used in this study for the years 2010 and 2020. In this study, NDVI, RVI, DVI, and SAVI indices were used to highlight changes in vegetation over the 10-year period. The results show that the amount of vegetation indices has almost doubled after a 10-year period, indicating that watershed projects have been effective in increasing vegetation.

In general, the role and importance of watershed operations in improving the condition of pastures, controlling erosion, preventing sedimentation and finally protecting water and soil is not hidden from anyone. The technical and principled implementation of watershed projects causes storage and infiltration of rainfall, increase of vegetation cover, stabilization of erosion and sedimentation, increase of the useful life of dams, adjustment of the slope of waterways and reduction of the speed and power of water destruction. Based on the studies conducted, due to the diversity of ecological conditions, it is not possible to reach a specific pattern or provide specific instructions with the same application in all watershed areas. For this reason, in addition to knowing the area and its issues, it is inevitable to prioritize watershed management operations according to the existing potentials. Examining the results of the conducted research shows that the implementation of watershed operations in watersheds has played an important role in controlling surface runoff. In a study, they evaluated watershed projects on the flood level of the Ramyan area using the HEC-HMS model, and the results showed that the flood has decreased in the period of different returns; In such a way that the greatest decrease in peak discharge and flow volume occurred during the return periods of 10 and 20 years, respectively, and with the increase of the return period, the effect of flood control measures on floods decreases. In this research, in order to evaluate the role of watershed projects in reducing peak flood discharge, HEC-HMS rainfall-runoff model was used, and the amount of discharge was calculated before the implementation of watershed management activities and after the implementation of watershed management activities, and the effect of these projects on the peak flood discharge was determined.

Hossein Abad Jiraft watershed is located between 57' 34'' to 57' 43'' east longitude and 28' 19' 13 to 28' 26' 34' north latitude. The area of ​​the watershed is 11258.68 hectares. Also, the weighted average slope of the watershed is 17.83%. More than 60% of the area's land use is pasture, which is the dominant species. In this study, the HEC-HMS model version 3.1.0 was used to simulate rainfall-runoff. Also, the data of 20 climatology stations with a common statistical distance of 30 years (1986-2016) were used.The methodology must be clearly stated and described in sufficient detail or with sufficient references. In order to calculate the amount of losses, the American Soil Conservation Society (SCS) method was used in the HEC-HMS model. The amount of runoff (Q) depends on the rainfall (P) and the water retention volume inside the soil. In all floods, runoff (Q) is always less than or equal to precipitation (P). Similarly, after the occurrence of runoff, the actual amount of water retention (Fa) is less than or equal to the maximum retention capacity (S). As can be seen, CN is the most important parameter to be estimated. CN for average humidity conditions (AMII) is obtained from the relevant table. CN is estimated from the combination of 2 factors of hydrological group and land use at any point of the basin, and CN of the entire basin is calculated from weighted averaging. In this study, to prepare the curve number (CN) map of the region, first, the map of soil hydrological groups in four groups A, B, C and D was prepared by combining the slope map and the map of hydrological units.

Results and Discussion :

According to the calculation method described in the previous section, CN was calculated in the sub-basins. The results show that the highest value of CN is estimated in sub-areas H12-1-1-2 with CN: 78.3 and sub-area H11int with CN: 76.9. According to the high value of the curve number in these two sub-areas, flash floods are expected to occur in these two the area is very large and generally the average area curve number is above 70. After completing the input data to the HEC-HMS runoff precipitation model, the model was run for different return periods (RUN) and the calculated peak discharge was extracted. A total of 67472 cubic meters of structures have been built in the entire Hossein Abad basin, including 3 stone and mortar structures with an area of ​​1139 cubic meters and 10 earthen dams with an area of ​​66339 cubic meters. The 13 created structures have a total reservoir volume of 222598.1 cubic meters. Due to the effects of watershed management activities, the concentration time of the basin changes and generally increases. This change can be estimated through two factors: the slope of the main waterway and the change in the condition of the cover (CN). The above information was calculated in the modified Kerpich relation of the concentration time and the delay time of each sub-basin of Hossein Abad, after watershed operation. Here, the changes include concentration time, CN and equating some factors with the effective level. By applying the effects corresponding to watershed operations in the runoff precipitation model, the model was run for different return periods (RUN) and the flood peak discharge after watershed operations was calculated.

Today, in order to implement watershed projects, a lot of money is spent in this regard, but perhaps less attention is paid to the effectiveness of these projects. In fact, without monitoring and evaluating these projects, it may not be possible to convince the policy-making managers to allocate credits and the people to voluntarily participate in the implementation and support of watershed projects. Watershed activities are considered as the most important flood risk reduction projects In this research, considering that the implementation of the Hosseinabad-Jiroft watershed project is very costly and is one of the important flood-prone areas of the region, the HEC-HMS rainfall-runoff hydrological model is used to simulate the peak flood discharge before and after the implementation of watershed activities in the Hosseinabad-Jiroft watershed to evaluate the effectiveness of this The projects were used to reduce the peak flow of floods. The results of this research show that watershed management activities in Hosseinabad-Jiroft region play an essential role in reducing the peak flood discharge. This reduction is more than 95% in some sub-areas, which indicates the impact of watershed projects and their effectiveness on the peak flood discharge. Therefore, it can be concluded that the HEC-HMS model is a suitable model for predicting runoff events. Due to the good performance of the HEC-HMS model, this model can be used to estimate floods in basins without statistics with appropriate calibration and obtain acceptable results. The HEC-HMS hydrological model has a good capability in predicting the real time of flood and therefore it was used in this research.

Long-term warming of the atmosphere, decrease in precipitation, drought and floods lead to the creation of climate change phenomena in natural and unnatural ecosystems. In addition, an increase in greenhouse gases, which cause the temperature to rise, also increases this phenomenon. Climate change affects different aspects of Mashhad city in terms of geographical location, tourism and tourism. In this study, using the CanESM2 model and the precipitation and temperature data of Mashhad station from 1961 to 2005, they were predicted in the near future from 2030 to 2060 and from 2070 to 2100 under RCP climate change scenarios. The results showed that the CanEMS2 model is in good agreement with the observational data and can be used to simulate the data in the future period. The simulation results show that the amount of precipitation will decrease in the near future, but not in the distant future. This parameter will also increase, but the temperature will increase in the future (near and far) and the phenomenon of global warming will increase. The results of this research can be used for environmental management and the services and industries that will lead to an increase in greenhouse gas emissions in Mashhad city can be used for proper policy and planning in order to reduce greenhouse gas emissions.

Dust storms are always known as one of the natural hazards that affect various sectors such as health, agriculture, transportation, etc. and have very wide consequences, especially reduced soil fertility, damage to crops, drying of cover. Natural plant causes disorders of communication systems, disorders of mechanical systems and an increased risk of respiratory diseases. In general, the main source of dust storms, or in other words, the main origin of dust storms is located in arid regions of the world such as East Asia, Middle East, Latin America, Australia, parts of Europe, East and South Africa, North America. In addition to the internal centers of the country, the main effective centers are the centers located in Iraq, Syria, the Arabian Peninsula and Afghanistan. In order to manage dust storms, forecasting and routing this phenomenon is of great importance. The lowest and highest range of dust suspended particles is from a few nanometers to 100 microns. Large particles usually move by rolling, medium particles by jumping, fine particles such as clay particles due to their lightness rise to a high height above the ground and remain suspended in the air for a long time and descend after a long distance. In suspension motion, very fine soil particles, after rising from the ground due to their extraordinary lightness and high specific surface area, remain suspended in the air for a long time and in the presence of favorable atmospheric currents, sometimes travel hundreds or thousands of kilometers and up to more than a few altitudes. They extend a thousand meters above the ground.

Jazmourian basin is the most important basin in the southeast of Iran, which is located in Kerman, Sistan and Baluchestan provinces with the latitude coordinates of 33 26 to 36 29 north and the longitude of 16 56 to 26 26 east and with an area of 69374 square kilometers. After statistical study of the phenomenon of "dust" and the factors affecting it in the Jazmourian basin, the severe and widespread occurrence of "dust" in the Jazmourian basin is investigated. First, in order to investigate the "dust" mass in the region, the true color image of the Madis sensor of the Tera and Aqua satellites and the optical depth values of the airships are examined. Then, to investigate the prevailing atmospheric currents in the region, the HYSPLIT model is implemented as a matrix and in a leading way. In implementing the HYSPLIT model, GDAS meteorological data with a horizontal separation of 0.5 degrees have been used. Using the output of this model, it is possible to investigate the transfer of "dust" particles from this area.

The True Color Composite and the light depth of the Aqua satellite sensor on October 7 and 8, 2018 show that the AOD values in the whole region are high every 2 days. Also, the True Color Composite of the MADIS sensor of the Aqua satellite shows the high values of "dust" concentration in the Jazmorian region. And they have gone to the Persian Gulf region. Particle optical depth values at UTC06 on October 8, 2018 show that AOD values on the North Sea of Oman have increased significantly and reached 1. Also, the amount of this quantity has reached 1 in the southern half of Jazmourian region, but it has reached 0.7 in a large part. Particle optical depth values at UTC12 on October 8, 2018 show that AOD values on the north of the Oman Sea have increased and reached 1.2. Also, the amount of this quantity has reached 1 in the southern half of Jazmorian region, but has reached 0.7 in a large part of Jazmorian region. Also, the values of the optical depth of the particles at UTC18 on October 8, 2018 show that the AOD values on a large part of the Oman Sea remain 1.2. But the amount of this quantity has decreased in the southern half of Jazmourian region and has reached 0.7 only in a small part of Jazmourian region.

Dust from these areas can directly affect the provinces of Kerman, Sistan and Baluchestan, as well as Hormozgan. Therefore, it is very important to study the path of particles as well as the dust collection centers. In this study, the beginning of the dust storm from October 7 to 8, 2018 was selected for simulation and navigation. The results showed that the southern parts of Jazmourian basin (wetland area and its surroundings) can be used as a critical dust center in these areas. Particles from these areas also move towards the Sea of Oman, which affects most of Hormozgan province and southern Sistan, and is also important for navigation and navigation systems.

Vegetation is the first and the most important producer of any ecosystem and reflects many factors in the ecosystem, so by studying the relationship between its changes and other factors such as dust, the interaction of factors can be understood. The purpose of this study was to investigate the effect of vegetation cover and its relationship with the occurrence of optical depth of air (AOD) caused by dust events in Hormozgan province during the study period of 2000 to 2020 by using NDVI, SAVI vegetation indexes and other climatic variables.

The present research investigated the relationship between dust and vegetation. For this purpose, aerosol optical depth (AOD), which is one of the most widely-used indicators for analysis and monitoring of suspended particles in the atmosphere, was used. To determine the dust areas, the AOD index was normalized; then the numerical value of AOD> 0.5 was considered as the high amount of dust. For studying the trend of AOD change, by coding in the Google Earth Engine environment(GEE), the image of MODIS dust products from 2000 to 2020 (20-year period) was extracted and subsequently the dust time series diagram was prepared. According to this chart, the month and year that had the highest level of dust during this period were determined. The NDVI and SAVI indexes during the years (2000-2020) were coded for an average of three months (June, July and August) in the Google Earth engine environment and all satellite images from Landsat 5, 7 and 8 sensors were extracted with a resolution of 30 meters. Then the correlation between vegetation indices and climatic variables with AOD index were calculated.

The results showed that June, July and August had the highest AOD index during the study period and the lowest level was in December of each year. The largest AOD occurred in July during the study period. The most severe case occurred in July 2018 with a magnitude of 0.69 and the lowest case was in December 2000. The charts illustrated that the largest level of dusts occurred in 2003, 2011 and 2018 and the lowest levels occurred in 2000, 2002 and 2017 in Hormozgan province. The results showed that, among the climatic indicators, evapotranspiration, minimum temperature and wind speed had the highest correlation with AOD index. Also, from 2000 to 2020, the rate of evapotranspiration and temperature increased with a slight slope, and due to the direct relationship between these factors and the AOD index, the AOD index increased during the period. The results of correlation between SAVI and AOD showed that there was a slight or weak relationship between them and the correlation index between NDVI and AOD showed a moderate to strong relationship.

The results of the study indicated that the changes in the AOD index in the twenty-year period (2000-2000) have no significant trend and have been mostly influenced by climatic factors and vegetation density in Hormozgan province. Also, the results of studying the spatial pattern of AOD in the province showed that the distribution of AOD in the south to south-west is more than the south-eastern regions of the province. The results showed that the condition of surface vegetation was significantly related to the amount of AOD and their levels increased with decreasing vegetation. Studies have shown that in areas of the province where vegetation is sparse and barren compared to other parts of the province more AOD exist. Also in years when vegetation is less dense due to reduced rainfall, the intensity of dust has increased in these years. The results showed that 2018, 2008 and 2003 years showed the dustiest days and 2000 and 2017 showed the least dusty days per year. According to the results, the highest amount of AOD occurred in the south and southwest of Hormozgan province, which matched the results of NDVI index in these areas according to which vegetation is in the class of 0.1-0 (without cover). This confirms the results of the relationship between dust and vegetation.

Dust storms caused by erodible surface sources, such as deserts, have been one of the major natural disasters in recent years, affecting countries in the Middle East, including Iran. One of the major factors to formation the dust storms is the strong wind flow that can be created in the presence of low pressure systems in the potential. Therefore, the study and identification the atmospheric patterns can be effective in predicting these storms. One way to study dust storms is to use numerical models that can be used even for times when appropriate data is not available and also to predict these types of storms.

After statistical study of the phenomenon of "dust" and the factors affecting it in the Jazmourian basin, a severe and widespread event of "dust" in the Jazmourian basin is investigated. Then, to investigate the prevailing atmospheric currents in the region, the HYSPLIT model is implemented as a matrix and in a leading way. In the implementation of HYSPLIT model, GDAS meteorological data with horizontal separation of 0.5 degrees have been used. Using the output of this model, it is possible to study how dust particles are transferred from this area. Finally, each of the studied dust phenomena is simulated using the WRF-Chem model to determine how the dust is emitted and transmitted in the region.

Leading HYSPLIT model output for November 28, 2016 UTC12 clock which was executed as a matrix with GDAS data with 0.5 degree horizontal separation for 36 hours at a height of 100 meters. The results showed that the particles from this region were affected by northwestern currents and were transferred to Sistan-Baluchestan province and the border between Iran and Pakistan. Aerosols optical depth of the output particles of the WRF-Chem model at UTC12 on November 24, 2016. Values higher than 0.5 indicate a high amount of suspended particles in the atmosphere in the study area. At this time, the highest light depth of particles is in the Strait of Hormuz and Qeshm Island, but the concentration of particles in a large part of Jazmourian region is between 0.4 to 0.6, which can indicate the presence of dust particles in the atmosphere. The results also show that the concentration of "dust" on the Oman Sea and the Persian Gulf is higher than 5000 micrograms per cubic meter. Also, the concentration of "dust" in Jazmorian region is high and is higher than 1500 micrograms per cubic meter. Also in some areas, the concentration of "dust" is more than 5000 micrograms per cubic meter.

In the present study, using the outputs of the WRF_Chem model, the dust phenomenon and its characteristics in the southeastern region of Iran have been identified. According to the results, the WRF_Chem model provides a reasonable estimate of the weather in the study area in terms of scale and time changes. By producing dust particle concentration distribution maps, areas of the simulation basin that have the maximum particle concentration were identified as the main sources of particle emission. In general, the performance of the WRF / Chem numerical model in this study confirms the applicability of this model in modeling and forecasting air quality, especially for air vents produced from natural emission sources such as erodible areas of deserts. The results showed that the studied dust phenomenon (November 24-27, 2016) dust particles from Jazmourian basin, were affected by northwestern currents and were transferred to Sistan and Baluchestan province and the border between Iran and Pakistan.Keywords: simulation, Dust storm, WRF/Chem model, MODIS.

In the present study, using the outputs of the WRF_Chem model, the dust phenomenon and its characteristics in the southeastern region of Iran have been identified. According to the results, the WRF_Chem model provides a reasonable estimate of the weather in the study area in terms of scale and time changes. By producing dust particle concentration distribution maps, areas of the simulation basin that have the maximum particle concentration were identified as the main sources of particle emission. In general, the performance of the WRF / Chem numerical model in this study confirms the applicability of this model in modeling and forecasting air quality, especially for air vents produced from natural emission sources such as erodible areas of deserts. The results showed that the studied dust phenomenon (November 24-27, 2016) dust particles from Jazmourian basin, were affected by northwestern currents and were transferred to Sistan and Baluchestan province and the border between Iran and Pakistan.

Integrated water resources management is recognized as one of the main needs of any society due to population growth and technological advancement. To implement integrated water resources management, modeling of this system is essential. On the other hand, water resources systems are highly complex and affected by various factors that are very difficult to identify and determine their role in water resources management. The purpose of this study is to prepare an integrated model taking into account economic, social and environmental dimensions using the system dynamics approach in the southern region of Kerman. To conduct this research, first in the framework of DPSIR cause and effect, a conceptual model of the region was prepared, in which the effective factors on water resources were identified. Then, different components of the basin were modeled with the approach of systems dynamics by specifying the patterns governing the region. Vensim software was used for modeling based on the system dynamics approach. After modeling, the model was validated and evaluated in different ways and it was used in the evaluation, policy-making and planning stages of the basin. The results showed that the cause-and-effect framework of DPSIR and the system dynamics-based approach for evaluating and simulating different policies in the study area are efficient and useful. In addition, the results showed that in the current scenario, the water adequacy ratio for agriculture will decrease from 0.55 in 2006 to 0.2 in 2031, but in the scenario of increasing water supply resources, the water adequacy ratio for agriculture will reach 0.9 in 2031.

Flood damage assessment is often necessary for early flood management. To this end, this paper provides a framework of rapid estimation of flood damage and identification the flooded areas in March 2020 using Sentinel-1 satellite data. To this end, in the present study, after applying the necessary pre-processing in SNAP6 software, the backscattering coefficient, or sigma naught for two images related to before and after the flood occurrence was extracted. The backscattering coefficient histogram was used to separate the image into two classes including water and non-water and the threshold of 0.01 was obtained based on it. Then, by applying mathematical operations on both backscattering images, the binary image of water and non-water was prepared and the flooded areas were determined based on the difference between the two images. After detecting the flooded areas, Sentinel images were classified into three classes including waterbody before flood, flooded area and other lands using supervised classification algorithms. The results indicated the high accuracy of the Random Forest algorithm with kappa of 0.92 compared to other algorithms. By overlaying the land use and flooded areas maps, the inundation percentage for each land use was determined. According to the results, bare lands with 27.9 percent, residential land with 16 percent and rangelands with 12 percent had the highest inundation percentage, respectively.

Changes in water cycles in different parts of the world is one of the effects of climate change in recent decades. Evapotranspiration, as the part of the hydrological cycle, will also undergo these changes. Therefore, in the present study, the effect of climate change on potential evapotranspiration changes in Halilrood Watershed, under RCP2.6, RCP 4.5 and RCP 8.5 scenarios using LARS-WG downscaling model and the output of the general circulation model of HadGEM2 in future (2021-2040) was studied and the rate of evapotranspiration at the basin scale was calculated based on the predicted climatic parameters using Tornthwaite method in future. According to the results of the LARS-WG model, in the study area, precipitation will decrease and the temperature will increase under all scenarios in future compared to the baseline period. Evapotranspiration will also increase based on the predicted temperature and precipitation. So that, at the basin scale, evapotranspiration will increase by 3.4, 6.8 and 8.5 under RCP 2.6, RCP 4.5 and RCP 8.5 scenarios in future (2040-2021), respectively. According to the results, the highest increase in temperature and evapotranspiration and the highest decrease in precipitation at the basin scale is related to the RCP 8.5 scenario. The results of this study can be used in studies related to water resources management, agricultural and environmental studies.

Introduction :

Jazmourian basin in southeastern Iran includes parts of Kerman and Sistan, and Baluchestan provinces. This region is one of the sources of dust production in southeastern Iran. The maximum dust emissions in the Sistan region occur in eastern Iran, southwestern Afghanistan, and Pakistan in the summer, and these storms load dust from local scales to regions. Vegetation and its type also play an important role in the severity of dust. There is positive feedback between precipitation and dust emission from the surface; This means that the dust from desert areas reduces rainfall and decreases rainfall, causes the soil to dry out, and further increases dust. In addition to the effect on rainfall, the presence of dust is also effective in its spatial distribution.

 In this study, first, using the optical depth data of the MISR sensors of Terra satellite with a horizontal separation of 0.5 degrees, the monthly and seasonal average optical depth of the aerators in the Jazmourian basin is determined. In order to study the trend of AOD change, the average AOD regions of TODRA satellite MODIS sensor are shown annually in the period 2000 to 2020, and the regression line slope was calculated by age estimation method and Mann-Kendall method with 95% and 99% confidence levels. The amount of vegetation changes in the region has been studied using the annual average of the NDVI index in the Jazmourian region. Since precipitation is one of the factors affecting the occurrence of dust events, the average annual precipitation rates of the TRMM satellite have also been studied. Finally, to investigate the effect of vegetation change on dust, the correlation between the average annual data of AOD and NDVI data and the correlation between the average annual rainfall data and NDVI was calculated to investigate the effect of annual rainfall on vegetation.

Results :

 The monthly average values of the optical depth of air vents were in the period 2000 to 2020. In January, AOD values in the center of the Jazmourian Basin, located on the border of Sistan and Baluchestan and Kerman provinces, are slightly higher than in other parts. From February to July, an increase in AOD is observed in the region so that in large parts of the Jazmourian Basin, the average optical depth of air vents in this month has reached about 0.6. Since August, AOD values have gradually decreased until December; only in the central areas of the basin, small amounts of AOD are observed. As expected, the maximum AOD in this region is observed in summer, and then in spring is in second place. The amount of AOD has decreased significantly in autumn and winter. According to the results, NDVI values were low in years when the mean optical depth of the particles was high. For example, in 2008 and 2012, when AOD values were higher than in other years, the average annual NDVI values decreased. Interestingly, the average annual values of optical particle depth in 2020 and 2017 were lower than in other years, but in the same years, the average annual NDVI values are higher than in neighboring years. The results show that in the years when there is an increase in rainfall in the region, an increase in vegetation and a relative decrease in AOD compared to previous years are also observed. It should be noted that in some years, with increasing rainfall and vegetation, the amount of AOD has not decreased much that it can be said that the amount of AOD, in addition to the activity of local dust sources, is due to dust particles from other areas to the study area and AOD changes only Not due to changes in rainfall and vegetation in the area.

The average monthly light depth values of air vents in the period from 2000 to 2020 show that in January, the AOD values in the center of Jazmourian Basin, located on the border of Sistan and Baluchestan and Kerman provinces, are slightly higher than other sectors. From February to July, an increase in AOD is observed in the region so that in large parts of the Jazmourian Basin, the average optical depth of air vents in this month has reached about 0.6. From August, when small amounts of AOD were observed only in the central areas of the basin, AOD values gradually decreased until December. Also, the average monthly AOD values in the region in the period 2000 to 2020 show that the highest AOD values in July are related to 2003 and 2001, and in June are related to 2008, which is significantly different from other years. Examination of the seasonal average values of the optical depth of air vents in the period under study shows that the maximum amount of AOD in this region is observed in summer and then spring, and AOD values in the autumn and winter seasons have decreased significantly.

Climate change is now recognized as one of the key environmental challenges of the 21st century. Earth warming has been heightened by global warming along with falling rainfall. In this regard, by using statistical exponential downscaling models and climate change scenarios (A2 and B2), prediction of temperature and precipitation parameters in the southern region of Kerman province has been investigated. The results showed that the precipitation values ​​in the future period compared to baseline at Bam synoptic station increased by 7.32 and 8.46 mm, respectively, in scenario A2 and scenario B2. Also, the results showed that precipitation values ​​in the upcoming period compared to baseline at Bam synoptic station increased by 7.32 and 8.46 mm, respectively, in scenario A2 and scenario B2. On the other hand, at the synoptic station of Jiroft, the average season temperatures were in the scenario A2 (24.79, 8.88, 17.38, and -48.5), the temperature increase in the spring and summer and the decrease in the temperature in the fall and in winter, the values in the scenario B2 are (26.41, 10.8, 16.65, and 6.27), respectively, in the spring and summer and the fall in winter and autumn.

Today, dust is a major challenge for human societies. Dusts have a significant impact on the Earth's radiation budget, global biochemical cycles, soil formations, and chemical compounds in the atmosphere. This phenomenon can affect public health indicators. The Iranian Central Plateau is located in arid and semi-arid climates; it is more likely to face this phenomenon than other regions. Dust management and control depend on identifying critical hotspots and stabilizing the harvesting area. The aim of this study was to identify internal dust sources using the vertical dust flux parameter.

Kavir and Loot deserts cover a large area of the Iranian Central Plateau. In this study, the WRF-Chem model and GOCART and AFWA wind erosion schemas were used to identify dust springs. Emission fluxes were used to detect dust springs. In this regard, a severe storm was selected on 05/22/2018 by WRF-Chem model for simulation. In order to verify and select the best wind erosion schematic of the Iranian Central Plateau, the data of MERRA2 re-analysis database and surface dust concentration values ​​were used.

The results showed that the outputs of GOCART and AFWA schemas were different. The GOCART schemas identified three strong dust sources in the study area that were located in the Jazmourian Basin, the Loot Basin, and the Central Desert (Kavir Desert), but the AFWA schemas were able to identify only one weak source in the Loot area. The results showed that Loot Desert Center, south of Jazmourian Basin, as well as Dasht-e Kavir Desert Center (Central Desert) are known as internal dust sources. So that from one square meter of these areas, it is possible for 5800 micrograms of dust to rise into the atmosphere per second. Due to the fact that the storm lasted for 12 hours, about 2 tons and 505 kg of dust were transferred to the atmosphere from each hectare of internal dust springs. The results of the GOCART schema were more consistent with the three-hour time-series data of the MERRA2 re-analysis database and were selected as the best wind erosion schematic in the Iranian Central Plateau.

The results showed that the WRF-Chem model had a good ability to resemble the dust flux in the study area. The results of the GOCART and AFWA schemas were different. The AFWA model estimated the internal dust sources to be very weak. However, the GOCART model well detected internal dust sources.

In recent decades, the excessive use of groundwater resources has led to a drop in groundwater levels in most plains of Iran. To this end, the use of remote sensing techniques has recently expanded to study the fluctuations of groundwater levels. GRACE satellite data is a valuable new tool for groundwater monitoring and is currently the only remote sensing satellite which is capable of monitoring groundwater level changes. Hence, considering the special and critical conditions of Jiroft plain from the point of view of water resources, the study on the identification of the change of groundwater resources (as the main water resource in the region) have special importance. Therefore, the purpose of this study is to investigate and analyze the fluctuations of groundwater levels in Jiroft plain using GRACE satellite images from 2003 to 2016

This study investigates the trend of groundwater level changes in Jiroft plain using GRACE satellite images during 2003-2016. In this regard, the data was firstly processed in Google Earth Engine based on three algorithms, including JPL, GFZ, and CSR, and their results were compared with observational data (piezometric) from 2003 to 2016. This comparison was performed by examining the linear correlation between the changes obtained based on the GRACE satellite algorithms and the observational data. Also, for temporal and spatial analysis, the aquifer water level was mapped using Kriging method in ARCGIS software.

The results showed a good correlation between algorithms and observational data. According to the results, JPL algorithm with 64% correlation was the most suitable model for monitoring the quantity of groundwater in Jiroft plain. The results of groundwater mapping from 2003 to 2016 indicated the most drop of groundwater level in the central, western and southwestern parts of Jiroft plain, due to more wells and the expansion of agricultural activities in these regions. The examination of groundwater change trend showed that both observational data and JPL, CSR, and GFZ algorithms had a significant decreasing trend at the level of 5%. The similarity trend of observational data and algorithms also indicated the relatively good accuracy of GRACE images to investigate the groundwater level fluctuations.

The recent droughts and increasing the number of exploitation wells have led to the decrease in groundwater levels. Therefore, the assessment of groundwater level fluctuations of Jiroft plain is necessary. In this study, GRACE satellite data were used to evaluate groundwater level fluctuations in Jiroft plain. The results of groundwater mapping from 2003 to 2016 indicated the most drop of groundwater was related to regions with more wells and more agricultural activities that are in line with Hao et al., 2019. The study of linear correlation between the results of the three algorithms of GFZ, CSR, JPL, and piezometers, showed a good correlation between the algorithms and the observational data. According to the results of JPL model with 64% correlation, it was the most suitable model for monitoring the groundwater level in Jiroft plain. Considering the appropriate correlation obtained, it can be concluded that researchers and organizations can apply GRACE data as a low-cost and easy method to monitor and analyze groundwater level fluctuations that are compatible with the findings of Farokhnia and Morid (2014); Faraji et al., (2017) and Nabavi et al., (2020). Investigating the change trend of groundwater showed that both observational data and JPL, CSR, and GFZ algorithms have a significant decreasing trend at the level of 5%. The similarity trend of observational data and algorithms also indicated the relatively good accuracy of GRACE images to investigate the groundwater level fluctuations. The findings of Farokhnia et al., (2014) also showed the similarity of changes trend of the total water balance of the basin by the Grace satellite and the observational data.

Today, the phenomenon of dust is known as one of the most important natural disasters in arid and semi-arid regions. The long-term effects of this phenomenon on the human health index are referred to as chronic disease. Therefore, studying and identifying the patterns and centers of this phenomenon seems necessary in these areas. In this study, in order to simulate the dust emission flux to determine the internal and external critical centers in the central plateau of Iran, WRF-Chem model and GOCART wind erosion scheme and storm were used from July 19 to 21, 2015. The results showed that the Arabian deserts in Saudi Arabia, the deserts of Iraq, as well as the Gharegham desert in Turkmenistan and the Helmand region in Afghanistan are among the most important foreign crisis centers affecting Iran's central plateau atmosphere. Also, the Central Desert (Dasht-e Kavir) has been identified as the main source of dust and the southern parts of the Central Loot Basin and the Jazmourian Basin have been identified as the internal sources of dust. The results also showed that in the Central Loot basin, the amount of 6900 micrograms per square meter of dust increases per second due to the erosion conditions.

The dust phenomenon is of particular importance because of its close association with public health. Many researchers are looking for ways to reduce the harmful effects of this phenomenon. To this end, having information about the nature of the spatial and temporal pattern of this phenomenon is of particular importance to all researchers. Dust is one of the natural hazards of the central Iranian plateau. In this study, statistical analysis was performed on a yearly and monthly basis in the period 2006 to 2018 using codes 06 and 07 obtained from 50 synoptic stations located in the study area. Also the spatial pattern of dust days with horizontal views less than 1000 m, 1000 to 1500 m and 1500 to 3000 m in the study area was plotted. The results also showed that Tabas synoptic stations with 661 days, Arak with 528 days and Zahedan with 511 days with 1500 to 3000 m horizontal view were more important in the study period. Also, the results of seasonal survey of dust days in the statistical period showed that spring with more than 42% had the highest occurrence of dust. The results showed that in the horizontal view of less than 1000 m, Zahedan station with 113 days and Tabas station with 91 days of dust had higher frequency. Meanwhile, Zahedan and Shahreza stations with 91 and 55 days of dust with a horizontal view of 1000 to 1500 meters also had the highest frequency of dust days in the study area. Monthly statistical analysis revealed that most of the dust events were recorded in June and May. The results of spatial variation of dust days showed that there is no regular spatial pattern due to the extent of the area but in general in all three classes of horizontal view the focus of this phenomenon is most of the southeastern part of the study area.

Dust has a significant impact on radiation budget, global biogeochemical cycles, soil structure, atmospheric chemical composition, air quality and public health. Natural and human factors have increased the frequency and severity of dust storms in the country in recent years. The most important natural factors are rainfall, drought persistence and global warming, and human factors include surface water control, agricultural development and uncontrolled groundwater consumption, land degradation and excessive use of climatic and ecological potential of the region. These factors can lead to the development of dust centers and increase their activity.

This study was conducted in Central Iran, where one of the most important environmental problems in this region is the occurrence of destructive dust storms. Arid and semi-arid climate, bare soil with sparse vegetation and severe storms are the characteristics of the central region of Iran that prepare the conditions for the occurrence of dust storms. The provinces of Kerman, Yazd, Isfahan, western parts of Sistan and Baluchestan, Semnan province, Khorasan Razavi are directly affected by the consequences of these events. In order to analyze the frequency of dust days, dust codes taken from 37 synoptic meteorological stations with longer statistics were used. For each station, the number of dust days on an annual scale in the statistical period 1999 to 2018 was extracted. In order to analyze the frequency of dust days, Professional5 Easyfit statistical software was used, based on which the most appropriate statistical distribution function for each synoptic station was selected. EasyFit Professional software fits data into 61 distribution functions. Then, using the Kolmogorov-Smirnov test, the most appropriate probability distribution function was determined.

The results show that the statistical distribution of Johnson SB was found to have the highest frequency in the study area. The Log-Logistic (3P) statistical distribution ranks next. A number of stations such as Bam, Kerman, Nain, Arak, Saveh, Mahallat, Zabol, Semnan, Qom, Zahedan, Yazd and Tabas can have more than 100 days of dust in the return period of 50 or 100 years. Also, Tabas, Qom, Yazd, Zabol, Zahedan and Arak stations show at least 50 days of dust every year. The zoning of dust days with a return period of 5 years also shows that the southeastern parts of the study area, as well as areas in the center and northwest of the basin, can be identified as sources of internal dust. The zoning of dust days with a return period of 25 years shows that the southeastern parts of the study area below the Loot basin and also the northeastern parts of the study area below the central desert basin (desert plain) can have a maximum of 225 dust days in the return period. The results of frequency analysis of dust days with a return period of 50 years show that in some areas of the study area, more than 276 days of dust per year can occur and these areas are identified as dust sources in the study area.

In recent years, dust events in the West Asian region have occurred with greater frequency and intensity. Dust phenomenon in Sistan and Baluchestan, Kerman, Yazd, Isfahan, Semnan and Khorasan Razavi provinces is one of the most important challenges.  Identifying and predicting dust source in these areas are of great importance.One of the most important forecasting methods in different return periods is the use of statistical distributions. In this study, using 61 statistical distributions and Easyfit Professional 5.5 software, the most appropriate statistical distributions were determined using the Kolmogorov-Smirnov test, the most appropriate probability distribution function in the study area. Johnson SB statistical distribution was found to have the highest frequency in the study area; also, Log-Logistic (3P) statistical distribution is in the next rank. Then, using statistical distributions to identify indicator stations, the number of dust days in the return period was estimated from 2 to 100. The results showed that Bam, Kerman, Naein, Arak, Saveh, Mahallat, Zabol, Semnan, Qom, Zahedan, Khoor and Biabanak, Yazd and Tabas stations according to the analysis of the frequency and number of dust days estimated in the annual return period to Index station were identified in the study area. Also, changes in the spatial pattern of dust in the return periods of 5, 25 and 50 showed that the southeastern parts of the study area of Kerman, Sistan and Baluchestan provinces due to the proximity of Hamoon and Jazmourian wetlands and 120-day winds of Sistan as one of the dust centers have been identified.

Over the past few decades, there have been many global efforts to combating and mitigating desertification, and one of the most important actions is the United Nations Convention on the combating desertification. The present study aimed to assess the severity of desertification and identify the most important factors affecting land degradation in the Jazmurian basin. In this study, the IMDPA model was used to assess the desertification severity. Due to the time and cost limitations, two criteria for water and climate were selected. At first, by determining the geometric mean of the indices and then the criteria, the total desertification was calculated and the quantitative value of the indices and criteria and the final desertification were divided into four classes: low, moderate, severe and very severe. Then, using GIS, the desertification intensity map of the area was drawn up in the study periods. The results showed that in the study area, the water criterion was dominant and classified with a weighted mean of 3.2 in the sever class. Subsequently, the climate criterion with a weighted mean of 2.4 was in the next rank. The results indicated that the most important desertification indices in the study area were groundwater drop, electric conductivity of water, precipitation, TRANSO Drought Index, Drought Continuity Index and SPI index.

Desertification is one of the major challenges of the 21st century. Destruction of water resources, degradation of soil, as well as degradation of vegetation is desertification symptoms. This challenge is not restricted to dry areas, but can be applied in all regions, especially dry, semi-arid, and humid areas. Destroy the affected environment. Therefore, knowledge of its severity can play a significant role in water resource management. In this study, the IMDPA model, which is native to Iran, has been used to predict the desertification of Kerman plain in terms of climate criterion in 1409. Study of climate criteria and its score in the study area is from three indicators of annual precipitation, SPI drought index and drought persistence index. Using predicted precipitation values ​​by LARS-WG model and IMDPA model, the annual precipitation index score was 3.8, the index of drought persistence index was 0.7 and the SPI index was estimated 3.5 points. In the GIS environment, all indicator mapping maps it was drawn up.
The results showed that the annual rainfall index is very severe in the desertification class, the index of drought persistence in the low desertification class, and the SPI drought index in the severe desertification class are located, and the geometric mean of these indicators and their synthesis intensity The desertification of the area on the horizon of 1409 is in severe class. The results of this study can help in the management of desertification processes in the region.

By identifying the removal areas the reasons can be identified instead of addressing the causes, And focused on executive activities in the harvesting areas And for this, the identification of sediments is particular importance In this paper, with the aim of better understanding and interpreting sedimentary samples, Investigating and analyzing the distribution of sediments in the facies of the study area has been investigated. For this purpose, after sampling of surface soil and preparation of samples, The drying procedure was performed according to A.S.T.M standard in 8 classes, which was smaller than 64 microns to 4000 microns. By entering the data into Gradistat software, statistical parameters such as mid-diameter, skewness and sample sorting were calculated based on the Fulc's comprehensive drawing method. The results of the study showed that the particle sorting is between 0.8 and 0.3, which confirms the near-average spacing distance from the harvesting area to the sediment accumulation point. The results of the particle tilting index are in the median vein facies, agricultural lands, agriculture, and sandy areas with symmetrical pebble cover. In other facies, the index is tilted towards fine particles. In the facies of the Rigi plain, the puffy lands and the permafrost shells of the wear coefficient classes are between 0-200 and then fully angled and the particles are transported from a distance. In the rest of the facies, the wear coefficients are between 200 to 400, in which case the particles are semi-angled and the particles are transported from a relatively distant distance.

 Today, desertification is one of the most important natural phenomena that losses sometimes "irreparably affect human life. This phenomenon will gradually capture its surroundings and cause impoverishment and migration of affected areas." Assessment and Monitoring this natural phenomenon is one of the basic plans of regional planners to deal with it. Monitoring this phenomenon in Iran, which has more than two thirds of it in the dry and semi-arid region and has fragile ecosystems, is of paramount importance. Due to this, the IMDPA's native model was developed for its evaluation. In this study, for the purpose of the evaluation of the desertification intensity of Kerman plain was based on the IMDPA model with emphasis on water and climate criteria. The results showed that the climate class desertification class did not change during the ten-year statistical period (2003-2013) and is in the middle class and also the class Meanwhile, desertification was determined, and the results showed that in the water criterion the area of low desertification intensity was reduced and the average desertification class area was increased and eventually it became clear that with the passage of time, the desertification conditions of the region became worse, even the desert class Severe growth has also been observed in some areas, especially in the western and southeastern parts of Kerman plain.

The phenomenon of climate change is one of the most important environmental challenges that has been increased by the increasing emissions of greenhouse gases and has negative impacts on base resources such as groundwater resources. Therefore, it is essential that research is conducted to understand the impact of climate change on groundwater resources in the future period, to avoid the deterioration of the situation by proper management. Considering the importance of the subject in this study, the climatic model of LARS-WG and the GMS groundwater model were used to study the effects of climate change on groundwater under different scenarios in Kerman plain. In this regard, the climatic emission scenarios of A2, A1B and B1 of HADCM3 model was investigated in the period of 2011-2030 and to study the effect of climate change on groundwater drop, groundwater level was predicted using GMS software for the period 2012-2030 and the effect of climatic scenarios was studied on it. In order to groundwater modeling, the height of water in the piezometers was introduced to the model as a steady state in October 2002 and the values of hydraulic conductivity and recharge and boundary conditions were estimated. Then, the model was run for unsteady conditions for 2002 to 2013, and the groundwater level was predicted under different climatic scenarios for 2014-2030. The results showed that the average of groundwater drop in all four scenarios was -0.86, -5.85 and -9.19 meters (the first scenario), -9.26, -9.36 and -9.49 meters (the second scenario), -12.09, -12.21 and -12.28 meters (the third scenario) and -15.43, 15.55 and -15.58 meters (the fourth scenario) for A2, A1B and B1 scenarios, respectivelyThe phenomenon of climate change is one of the most important environmental challenges that has been increased by the increasing emissions of greenhouse gases and has negative impacts on base resources such as groundwater resources. Therefore, it is essential that research is conducted to understand the impact of climate change on groundwater resources in the future period, to avoid the deterioration of the situation by proper management. Considering the importance of the subject in this study, the climatic model of LARS-WG and the GMS groundwater model were used to study the effects of climate change on groundwater under different scenarios in Kerman plain. In this regard, the climatic emission scenarios of A2, A1B and B1 of HADCM3 model was investigated in the period of 2011-2030 and to study the effect of climate change on groundwater drop, groundwater level was predicted using GMS software for the period 2012-2030 and the effect of climatic scenarios was studied on it. In order to groundwater modeling, the height of water in the piezometers was introduced to the model as a steady state in October 2002 and the values of hydraulic conductivity and recharge and boundary conditions were estimated. Then, the model was run for unsteady conditions for 2002 to 2013, and the groundwater level was predicted under different climatic scenarios for 2014-2030. The results showed that the average of groundwater drop in all four scenarios was -0.86, -5.85 and -9.19 meters (the first scenario), -9.26, -9.36 and -9.49 meters (the second scenario), -12.09, -12.21 and -12.28 meters (the third scenario) and -15.43, 15.55 and -15.58 meters (the fourth scenario) for A2, A1B and B1 scenarios, respectivelyThe phenomenon of climate change is one of the most important environmental challenges that has been increased by the increasing emissions of greenhouse gases and has negative impacts on base resources such as groundwater resources. Therefore, it is essential that research is conducted to understand the impact of climate change on groundwater resources in the future period, to avoid the deterioration of the situation by proper management. Considering the importance of the subject in this study, the climatic model of LARS-WG and the GMS groundwater model were used to study the effects of climate change on groundwater under different scenarios in Kerman plain. In this regard, the climatic emission scenarios of A2, A1B and B1 of HADCM3 model was investigated in the period of 2011-2030 and to study the effect of climate change on groundwater drop, groundwater level was predicted using GMS software for the period 2012-2030 and the effect of climatic scenarios was studied on it. In order to groundwater modeling, the height of water in the piezometers was introduced to the model as a steady state in October 2002 and the values of hydraulic conductivity and recharge and boundary conditions were estimated. Then, the model was run for unsteady conditions for 2002 to 2013, and the groundwater level was predicted under different climatic scenarios for 2014-2030. The results showed that the average of groundwater drop in all four scenarios was -0.86, -5.85 and -9.19 meters (the first scenario), -9.26, -9.36 and -9.49 meters (the second scenario), -12.09, -12.21 and -12.28 meters (the third scenario) and -15.43, 15.55 and -15.58 meters (the fourth scenario) for A2, A1B and B1 scenarios, respectivelyThe phenomenon of climate change is one of the most important environmental challenges that has been increased by the increasing emissions of greenhouse gases and has negative impacts on base resources such as groundwater resources. Therefore, it is essential that research is conducted to understand the impact of climate change on groundwater resources in the future period, to avoid the deterioration of the situation by proper management. Considering the importance of the subject in this study, the climatic model of LARS-WG and the GMS groundwater model were used to study the effects of climate change on groundwater under different scenarios in Kerman plain. In this regard, the climatic emission scenarios of A2, A1B and B1 of HADCM3 model was investigated in the period of 2011-2030 and to study the effect of climate change on groundwater drop, groundwater level was predicted using GMS software for the period 2012-2030 and the effect of climatic scenarios was studied on it. In order to groundwater modeling, the height of water in the piezometers was introduced to the model as a steady state in October 2002 and the values of hydraulic conductivity and recharge and boundary conditions were estimated. Then, the model was run for unsteady conditions for 2002 to 2013, and the groundwater level was predicted under different climatic scenarios for 2014-2030. The results showed that the average of groundwater drop in all four scenarios was -0.86, -5.85 and -9.19 meters (the first scenario), -9.26, -9.36 and -9.49 meters (the second scenario), -12.09, -12.21 and -12.28 meters (the third scenario) and -15.43, 15.55 and -15.58 meters (the fourth scenario) for A2, A1B and B1 scenarios, respectively .

Drought is an insidious environmental phenomenon. This phenomenon causes water shortage for some activities, communities or environment. Drought should be compared with average climate and hydrological Conditions for Long period of time. Hydrological drought is detected by reduced water storage in lakes, underground water levels drawdown and reduced river flow and often will affect a large area. The most common definition of a hydrological drought is to define a threshold limit, such that if the river is less than that, a hydrologic drought is considered. In this study, the fixed threshold limit of Q70 was used in Karaj drainage Basin. Results showed that Q90 of year 1998 was the driest year. The results show that 1377 year was one of the driest years in this area and in Karaj station 284 days and for Gachsar station 255 days were dry. Also, the results show a total lack of water in Gachsar station Q70 threshold equal to 68/11 million cubic meters, Kalavan stations equivalent to 75.2 million cubic meters and for Karaj station equal to 44/42 million cubic. The general extreme value (GEV) best fit the parameters of the drought. The results can be used in water resources management and planning necessary to prevent or mitigate the effects of drought in the area.