Drought is one of the climatological phenomena that affect the vast majority of Iran, including Fars Province, in terms of metrological, hydrological, agricultural and socio-economical aspects. Quantitative description and monitoring of this phenomenon requires the utilization of drought indices. 

To evaluate various drought indices in the Fars province,  temperature, precipitation, and evaporation data of 113 stations in and close to the province (including synoptic, climatological stations and rain gauge stations) were collected and analyzed for 51 years (1966-2016). Additionally, 9 drought indices including SPEI, SIAP, DI, SPI, PN, MCZI, CZI, RDI and ZSI were employed. After ensuring data randomness, homogeneity, and normality, the three evaluation methods of minimum rainfall, normal distribution, and cross-correlation were utilized to select the most efficient drought index.

The SPEI index has the lowest difference between different drought classes compared to other indices based on the normal distribution method. According to the cross-correlation method, ZSI index has the highest correlation and similarity with the SPI index. Also, the minimum rainfall method showed that all indicators in the years of minimum rainfall show very severe and severe drought classes and this method cannot be a criterion for selecting the appropriate drought index.

In six years out of the 30-year period under evaluation, widespread severe drought had occurred across the province which include the years 1984, 1989, 1994, 2000, 2008, and 2009. Assessment of the indices for ten selected stations across the province indicated the two SIAP and RAI indices to yield similar outcomes.

Almost all regions of the world suffer from drought in one way or another. Various indices have been developed to better evaluate and understand the drought. Here, we investigate the spread of drought in the Neishabour plain using the data collected during the hydrological years of 1990 to 2018. Our dataset includes rainfall and minimum/maximum temperature collected by 13 climatological stations and 3 synoptic stations in the region. The drought was analyzed based on 6 indices: SPI, RDI, SPEI, aSPI, eRDI, and SPEIEP. For the first 3 indices, the total amount of precipitation was used, while for the rest, the amount of effective precipitation based on the USBR method was used. To better understand how drought spreads in the plain we needed to convert point data to regional data, to this end we investigated simple, ordinary, and general kriging of geostatistical methods. Our results showed that the two-by-two correlation coefficient between indices varied between 0.65 and 0.97. In all stations, the lowest R2 value belonged to the comparison between SPI and SPEIEP. In general, there was a high correlation in comparing the indices that used the amount of effective precipitation with corresponding indices that used the amount of total precipitation. Specifically, the comparison between eRDI-vs-RDI and aSPI-vs-SPI showed R2 values higher than 0.98 and SPEI-vs-SPEIEP showed R2 values higher than 0.96. In addition, SPI, aSPI, RDI, and eRDI indices were highly correlated with each other. This similarity of behavior exists in determining the most appropriate method of drought zoning in the studied area. To better dissociate between different methods and determine the optimum one, we looked at root mean square error (RMSE) values. Based on RMSE values the optimum method of zoning severe and extreme drought events was the ordinary kriging method. However, in the case of SPEI and SPEIEP, the most suitable zoning method was simple kriging. Furthermore, indices that use evaporation and transpiration better showed the extent of the drought area in recent years compared to the SPI index that only considers rainfall. This could be due to the effect of global warming on increase in evaporation and transpiration. We may therefore conclude that effective precipitation, precipitation, and evapotranspiration had a positive spatial correlation with each other in the study area because the findings of Global Moran's spatial autocorrelation index indicated cluster patterns for all 6 drought indices in the area. In most of the stations, a prominent cluster pattern was observed in the years with severe and very severe droughts, according to the local Moran's index results. Overall, our results suggest the usage of the SPEIEP index to monitor the drought in the Neishabour plain, considering the increasing temperature and also the smaller error of the SPEIEP index in determining the expansion of drought in the plain. In addition, considering that the SPEIEP index is relatively new and requires more studies in this basin and other basins, it is suggested that evaporation and transpiration be estimated with other methods such as Blaney-Kreider, Torrent-White, and Penman-Monteith and also effective precipitation with the other methods. Influence of the effective precipitation and evapotranspiration estimation method on SPEIEP index values should also be investigated. Additionally, it is recommended that more research be done on the spatial autocorrelation of drought in various geographic and climatic conditions across the country (Iran). If at all possible, it should also be looked into as how the severity of the drought or the geographical characteristics of the regions affect the degree of spatial autocorrelation of drought.

Iraq's Hammar marsh was a key region for food production economically. The Hammar marsh's ecosystem had started to deteriorate by 1980 because of the war. Ever since then it has had serious issues brought on by both natural and human causes. We highlight these issues, their links, and how social and economic forces led to environmental deterioration in this essay by focusing on globalization. We measured changes in ecological, economic, and social systems using a variety of metrics during the last 20 years in order to quantify the issues and chronicle the changes. Significant climatological changes, including decreases in precipitation and humidity as well as temperature rises, have influenced environmental deterioration in the Hammar marsh. The Hammar marsh's social structures were also subjected to a great deal of stress, including as conflict and sanctions. To determine how the environment has changed across three periods between 2002, 2012, and 2022, we computed and examined categorization changes in Landsat images. Throughout the research region, changes in climatological variables were linked to changes in the vegetation and water.

In this paper, a feasibility study is conducted on a photovoltaic-low-speed wind turbine-battery zero-energy building for a 175 m2 residential house in Gorgan. First, the climatological data of Gorgan City related to the amount of solar radiation and wind speed for the past 50 years have been extracted and then they are analyzed annually, monthly, and hourly using Climate Consultant software to check how Renewable resources can be used to produce clean energy. To determine the number of devices required, the annual energy requirement of the residential unit should be estimated. For this purpose, the power and energy consumption of the residential unit has been estimated based on its consumption data in the last year and analyzed using RETScreen1 software. The designed zero energy system has energy exchange with the grid and sends excess energy to it. The results of climate data analysis show that there is a possibility of wind and solar energy efficiency in this region. Although the price of energy in the region is low, due to economic efficiency, the lack of non-renewable energy resources, and the need to replace these resources, the use of wind turbines and solar panels to supply the required electrical energy is necessary.

Understanding the daily weather types of any specific location is crucial for identifying its long-term climate patterns. In this study, we utilized the Wos classification method in conjunction with a comprehensive climatological approach to analyze key variables, including minimum, average, and maximum temperatures, as well as cloud cover and daily precipitation. Data from 1985 to 2021 were collected from 39 synoptic stations, which exhibited a well-distributed representation across the country and provided complete datasets. Weather types were identified using established coding techniques. The findings indicated that the predominant temperature types in the country are primarily categorized as hot and very hot, with sub-codes reflecting generally low to moderate cloud cover and negligible precipitation. Furthermore, the application of Ward's clustering method facilitated the identification of three distinct climatic groups. The geographical characteristics of each location, including factors such as altitude, latitude, proximity to the sea, and synoptic influences, play a significant role in the regional differentiation of these groups within the country. The outcomes of this research can be instrumental in developing weather calendars for various regions, with implications for numerous sectors including agriculture and tourism.

Natural Drought, a natural phenomenon that ranks foremost among all natural disasters in its impact on communities, demands a comprehensive study utilizing appropriate drought indices given its significance and detrimental effects on diverse regions, including Iran. Effective drought management strategies hinge on accurate identification of drought periods using suitable indices. Saravan County has experienced recurrent droughts in recent years, with severe consequences for agriculture, water resources, and socioeconomic conditions. Identifying drought's effects on environmental sustainability in this county and proposing effective measures to mitigate environmental degradation is crucial. This study employed eight drought indices to assess drought severity in Saravan County: Decile Precipitation Index (DPI), Percent of Normal Precipitation Index (PNPI), Palmer Drought Severity Index (PDSI), Standardized Water Supply Index (SWSI), Standardized Precipitation Index (SPI), Crop Moisture Index (CMI), Rainfall Anomaly Index (RAI),Effective Drought Index (EDI). The analysis revealed that areas experiencing drought conditions occupy the most extensive area in the region, with this category spanning vast areas in the central, western, northwestern, and eastern parts. The severe drought category encompasses a portion of the northern and northeastern region. The findings highlight the need for adopting a comprehensive approach to drought management in Saravan County, incorporating multiple drought indices to accurately assess drought severity and implement effective mitigation strategies. By understanding the spatiotemporal distribution of drought, policymakers and stakeholders can develop targeted interventions to safeguard the region's agricultural productivity, water resources, and environmental sustainability.

Drought stands as an inevitable natural disaster with no means of prevention. Its detrimental impacts extend across diverse sectors, including water resources, agriculture, and the environment. Drought is typically defined as a substantial scarcity of natural freshwater resources persisting over an extended period due to shifts in precipitation and temperature patterns. Consequently, periods marked by below-average rainfall often result in temporary drought, particularly in arid and semi-arid regions characterized by relatively high temperatures. Globally, drought events are classified into four categories: meteorological, soil moisture (agricultural), hydrological, and socio-economic. Studying drought becomes imperative for implementing optimal solutions and strategies to manage water resources and ensure food security, among other concerns.  This research utilizes the Pedj Drought Index (PDI), a unique and potent tool, to delve into drought analysis. The PDI, grounded in precipitation and temperature data, offers a more accurate and accessible understanding of drought's spatial and temporal characteristics. Based on yearly averages at stations, this innovative approach provides a fresh perspective on drought analysis. We gathered and scrutinized annual rainfall and temperature data from 20 synoptic stations in Northwestern Iran from 1987 to 2021 to conduct this study. The PDI's accuracy and accessibility make it a reliable choice for drought analysis, providing a comprehensive view of the situation.  From 1991 to 1995, most of the studied stations experienced wet conditions, while from 2013 to 2017, they faced a severe drought. The most extended wet period occurred in the south at the Bijar station (9 years), and the most prolonged drought period happened in the east at the Ardabil station (8 years). The maximum wet period based on the PDI index (9 years) was observed at the Bijar station, and the most prolonged drought period was at the Ardabil station (8 years). In the northwest of the country, the average duration of the most extended wet periods is 5.5 years, and the average duration of the most prolonged drought periods is 7.5 years. Additionally, the central station experienced two 5-year drought periods, and the Tabriz station underwent two 4-year wet periods. Based on the precipitation anomaly index, 60% of the stations (12 stations) showed a decreasing trend in precipitation anomalies, with the Sanandaj and Maragheh stations having a significant 95% decrease. In comparison, only 40% (8 stations) exhibited an insignificant upward trend in precipitation. The temperature anomaly index showed an upward trend in all studied stations, with only Bijar, Takab, Sarab, and Miandoab stations (highlighted in red) having a significant 95% increase. According to the drought index PDI, none of the stations experienced extremely dry (ExD) or moderately dry (MiD) conditions. The highest percentage of severe drought was observed in Zanjan (71.5%), moderate drought in Khalkhal (20%), and mild drought in Tabriz, Maragheh, and Piranshahr (42.85%). Severe dryness was observed in the Bijar station (42.85%), moderate dryness in Maku (17%), severe dryness in Takab, Khormabad, and Miandoab (71.5%), and highly severe dryness (71.5%) in Ardabil Province. These findings underscore the urgent need for effective drought management and water resource planning in the northwest region of Iran. These findings underscore the urgent need for effective drought management and water resources planning in the northwest area of Iran. Discussion and This study investigated the effects of annual mean precipitation and temperature changes on drought and long-term dry events using the PDI index in 20 stations in the northwest region of Iran, spanning five provinces over 35 years (1987-2021). The northwest Iran stations experienced wet periods from 1990 to 1994, dry periods from 1998 to 2001, and from 2013 to 2017. The most extended wet period was approximately 5.5 years, and the longest prolonged drought period was around 7.5 years. On an annual scale, the PDI could describe the spatiotemporal variations of drought and wetness in the study area to a considerable extent. Despite its simplicity, the PDI provided highly accurate results compared to common drought indices such as SPI and SPEI, which rely on statistical assumptions and distribution-related parameters. The stronger correlation of PDI with SPEI, as opposed to SPI, demonstrates the capability of PDI to explain the effects of precipitation and temperature changes on drought and wetness in the northwest region of Iran.

Drought is a severe hydrological event that can cause serious problems in human life. In this context, it can have adverse effects on water supply and quality, public health, agricultural productivity, land degradation, desertification, famine, etc. (Madadgar and Moradkhani, 2014; Li et al., 2020). In a general classification, drought events are classified into four different categories, meteorological, hydrological, agricultural and socio-economic droughts (Wilhite and Glantz, 1985; Khadr, 2016). Some of the well-known and common meteorological drought indices in drought monitoring include Palmer Drought Severity Index (PDSI), Drought Identification Index (RDI), Standardized Precipitation Index (SPI) and Standard Precipitation Evapotranspiration Index. Considering the significant role of evaporation and transpiration in the water balance, it is necessary to consider its effect when studying drought in a particular region. Based on this, RDI, which includes both precipitation and evaporation and transpiration, can be considered as a reliable indicator for drought monitoring (Moeinifar et al., 1400). According to importance of drought as a natural phenomenon in hydrological and meteorological studies, its monitoring and forecasting with a suitable approach can be important. The main role of Drought prediction in risk management, reducing the effects of drought on existing water resources and their optimal use, the possibility of rational decision-making by decision makers to minimize the damages caused by drought, as well as planning and managing resource projects. It has water. (Khadr et al., 2016; Madrigal et al., 2018; Beyaztas and Yaseen, 2019). Among the models worked till date, single Kstar and GPR models are the newest models for drought prediction.

 Drought is result of climate change and specific principle decrease relation to longterm mean margin.for local & time drought variation in disparate weather climate in Iran, nomination vector this variation can in water management and that designation to control variation aspects, these have mater role. In this study the drought variation trend using non-parametric Mann-Kendall in 28 synoptic stations from 1981 to 2010 were studied. Also local dispense survey with earth statistics in ArcGIS9.3 software accomplish. The results of trending drought using Standardized Precipitation Index (SPI) represent the different behavior of drought index in different climates. The results of SPI showed that the majority of climates surveyed have experienced annual drought period. The occurrence of droughts, dry climate with cool winter and hot sammer of the highest annual drought was observed. As this climate drought years mean occurrence percent 20.55 percent was observed. Mann-Kendall test results Standardized Precipitation Index (SPI) also Represents that in the 3 seasons, spring, fall, winter and annual scale significant trend increase. The most trend drought significant increase was observed in Sanandaj. Surveyed local dispense observed in annual scale The most drought in south-east of country was increase was observed. In seasons scale, drought local dispense was heterogeneous. But in winter season drought local dispense explanatory was normal drought pitch in country.

Among environmental stresses, drought stress is the most critical ecological constraint that has could affect yield and product quality. It is important better to understand the effects of high temperatures and drought stress because, according to the forecasts made and seasonal temperature changes, we are facing a drought. Almost half of all human food needs, especially in Asia, are met directly from cereals. Wheat is one of the most adaptable cereals in different climatic conditions. Starch and proteins are the main components in wheat endosperm that affect the quality of the final product. Starch composition in wheat has a decisive effect on seed quality, flour processing, and yield. Physicochemical properties and final application of wheat starch are closely related to the structure of starch granules and the distribution of amylose and amylopectin. The internal structure of A and B-granules are somewhat different in composition, size, gelatinization temperature, and physicochemical and functional properties that lead to changes in swelling strength, gelatinization, and adhesion properties. Protein and starch, not only directly but also indirectly through the creation of bonds and effects on various reactions, can have a significant impact on the quality of the bakery. For these reasons, its recognition and investigation during drought stress as the most critical biological structure of wheat from the point of view of agricultural economics is of particular importance. Two bread wheat cultivars named Navid, with medium to poor baking quality, and Pishtaz, with high baking quality, were used in this study. Two wheat cultivars were cultivated in three replications in the research farm of Shahed University of Tehran in November 2019. Irrigation once a week was used as a normal treatment and stopped irrigation at the bolting stage for drought treatment (The criterion of drought stress is 30% of the maximum field capacity). Each replication consisted of two rows of cultivation with a length of 2.5 m and distances of 25 cm. At 35 days post-anthesis, the seeds of each plant were harvested from the middle two third of the spike. Traits such as total starch, wet gluten, gluten index, grain protein percentage, Zeleny sedimentation volume, bread volume, flour moisture, hardness index, and water absorption in flour were measured. Also, total starch and granules are separated was analyzed by by FT-IR. Statistical analyses were performed with SAS software (version 9.4) and Average Comparison with t-tests at the level of 0.05. and 0.01. In both wheat cultivars, drought stress showed a significant decrease in total starch content. Also, between the two cultivars under normal and drought stress conditions, the amount of starch in the Navid cultivar decreased significantly. Under drought stress, loss of AGPase activity leads to premature cessation of starch accumulation. In both cultivars, drought stress caused a significant increase in wet gluten compared to the normal. The results showed that the shorter the time between flowering and seed ripening, the smaller the seeds and the higher the gluten content. Drought had no effect on the Pishtaz cultivar but was influential on the Navid cultivar and caused a significant decrease in gluten index. Also, in both normal and drought stress, the gluten index was significantly higher in the Pishtaz cultivar. some researchers have shown that high-quality wheat cultivars have a higher gluten index. Drought stress in both cultivars significantly increased seed protein. It has been proven that reducing starch under stress conditions disturbs the protein ratio to starch and increases the amount of protein per unit volume. In both cultivars, we saw an increase in the percentage of Zeleny sedimentation volume. The higher the gluten content and the better the gluten quality, the slower the deposition and the increased the Zeleny sedimentation volume. in measuring the percentage of bread volume, the drought did not have a significant effect in the Pishtaz cultivar. But, in the Navid cultivar, drought stress caused a significant decrease. Drought stress in the Pishtaz cultivar had no significant effect on wheat seed moisture. However, in the Navid cultivar, drought stress with a decrease significantly reduced the grain moisture. Low or high humidity can increase crop damage during harvesting and storage, increasing the cost of post-harvest processes to some extent. The Percentage of hardness index in the Pishtaz cultivar in drought stress conditions with a significant difference increased. But in the Navid cultivar, drought stress had no significant effect on the hardness index. A very strong correlation has been observed between the hardness index and the rheological properties of the dough, and the quality of gluten. Both wheat cultivars, drought stress significantly increased the water uptake percentage of flour. Higher Glutenin to Gliadin ratio under drought stress conditions may make gluten and dough more robust, and This is accompanied by an increase in water absorption by flour. Drought stress in the Pishtaz cultivar did not cause molecular changes, and the molecular structure remained constant. In the Navid cultivar, for total starch, A-granules, and B-granules in both normal and drought stress in the positions of the peaks did not change. However, the intensity of one of the peaks in the range of O-H bond tension showed a decrease in the condition of drought stress. Investigating the mechanisms that enable plants to adapt to drought stress and maintain their growth in these conditions ultimately helps select stress-resistant plants for cultivation in dry and semi-arid soil. In general, drought stress reduced the yield and baking quality of both wheat cultivars; of course, it was more in the Navid cultivar with medium to poor baking quality, which indicated that this cultivar is more vulnerable to drought stress than the Pishtaz cultivar. The results of this research can provide insight into the impact of potential mechanisms through drought on the ultrastructures and physicochemical properties of wheat starch and its relationship with baking quality.