Remote Sensing

Total Perceptible Water (TPW) is an important parameter in climatology and weather forecasting and is directly related to any climate process. There are three approaches to estimate this parameter i.e. using radiosonde, using GPS and calculating from satellite images where the first two are localized and the last one can give an instant view of TPW in a vast region. The algorithm used for the TPW calculation from MODIS images is related to the ratio of the reflectance in a water vapor absorbing channel and the reflectance in a non-absorbing channel. Due to strong horizontal variation in the surface reflectance in non-absorbing channels, the retrieved TPW varies strongly from one pixel to its neighboring pixels while it is believed that the horizontal gradient of TPW is very weak. To solve this problem, a damping coefficient was added to the non-absorbing channel reflectance. It is found that this coefficient differs for different surface covers. The current work presents a procedure for calculating these coefficients. The results of a comparison between modified TPW and those extracted from GPS data showed a R 2 of 0.81 whilst this was about 0.67 for non-modified MODIS TPW.

This paper presents the results of a geoarchaeological study of the ancient hydraulic structures in the Bozpar Valley and an analysis of their relationship with the standing monuments, especially the two palatial structures known as Kushk-e Ardashir and Zendan-i Soleyman. It presents a raison d’être for each identified structure regarding its hydraulic function and physical integration within the monumental landscape. Then, it suggests an interpretative pattern in their spatial relation to the mentioned monumental structures. The study area is a small and remote valley in the Zagros highlands in southern Iran. It borders the modern provinces of Fars and Bushehr and is historically associated with the Greater Fars region. The monumental structures in this area belong to the Sasanian architectural tradition. Here, their integrated hydraulic structures are investigated interdisciplinary via remote sensing. The analysis indicates different functions for the two monuments: a representative and official kushk and a [seasonal] leisure palace. Based on the nature and function of the integrated hydraulic structures, the former monument seems to relate to food production activities and the latter to currently unidentified activities other than daily life. The results of this study provide further evidence of integrated hydraulic structures in Late Antique Iran and shall trigger comparative studies from neighbouring regions in the future.

INTRODUCTION: One of the technologies that can have significant results in the field of crisis management is remote sensing, which has the ability to quickly and accurately assess floods and is considered an important and safe tool for reducing risk and responding to this hazard. METHODS: In this study, radar data was used to quickly estimate the areas affected by the flood in the Chabahar city in January 2020, and the Normalized Difference Water Index (NDWI) was used to verify the validity. FINDINGS: According to the research findings, the use of Sentinel-1 radar satellite data in critical situations such as flooding has a high potential for rapid and accurate monitoring of affected areas. Comparison of the results extracted from radar images with the NDWI based on Sentinel-2 optical images also showed that although there are differences between the two methods, a significant overlap was recorded between their results, indicating the relative validity of radar data for estimating flooded areas. CONCLUSION: Overall, it seems that the benefits of using radar images to estimate areas affected by floods are undeniable and that by optimizing the algorithms and methods used, desirable results can be achieved in line with the desired goal.

One of the environmental consequences and conflicts arising from land use and land cover changes is the intensification of soil erosion, which seriously threatens urban water and soil resources. Therefore, it is necessary to regularly identify the spatial dimensions of land use and land cover and their effects on cities so that policymakers and researchers can make informed decisions. Satellite data is one of the fastest and most cost-effective methods available to researchers for preparing land use maps. this study aimed to evaluate the changes in land use percentage and its impact on erosion between 1993 and 2023 in the city of Gomish Tappeh, located in Golestan province. For this purpose, a vegetation cover percentage map was first prepared using TM and OLI sensor images from the Landsat satellite. After atmospheric and radiometric correction, a land use map was created using the pixel-based method (maximum likelihood algorithm), the object-oriented method (nearest neighbor algorithm), and the ARAS method. The most important accuracy assessment methods, including overall accuracy and the classification kappa coefficient, were then extracted. An erosion zoning map was prepared using the resulting land use maps and factors including slope, lithology, distance from roads, distance from rivers, precipitation, and soil, using the Kritik weighting method and the WLC method. the results showed that in the land use maps from 1993 to 2023, the increase in rainfed lands was accompanied by a decrease in pastures, with the most significant change being a downward trend in pasture use. Additionally, according to the 1993 and 2023 erosion zoning maps, Gomish Tappeh is categorized as having both a very high risk and a high risk of erosion. The increase in the area of very high-risk and high-risk erosion classes in the studied basin can be attributed to the conversion of pasture-covered lands to rainfed agricultural lands, the plowing of pastures on steep slopes, the increase in residential areas on riverbanks, and the disregard for river boundaries, which accelerates the erosion process.

In the face of escalating climate change and its cascading impacts, urban resilience has become a fundamental approach to achieving sustainable city management. Zahedan, situated in an arid to semi-arid region, experiences severe climatic stressors including rising land surface temperatures, declining soil moisture, intensifying droughts, and increasing occurrences of dust storms. This study investigates the role of urban green spaces in reducing climate vulnerability and enhancing resilience, focusing on two neighborhoods with contrasting environmental conditions: Daneshgah (University) and Shirabad. Utilizing Landsat satellite imagery, spatiotemporal changes in vegetation cover (NDVI) and land surface temperature (LST) were analyzed for the period 1980–2023. Climatic parameters—air temperature, precipitation, humidity, and wind speed—were examined through time-series analysis and validated using the Mann–Kendall trend test. Furthermore, the TOPSIS multi-criteria decision-making model was applied to evaluate and rank neighborhood vulnerability and resilience levels. The results reveal a marked decline in vegetation cover accompanied by a significant rise in land surface temperature over the past four decades. Drought indices suggest that decreasing precipitation and humidity levels are primary drivers of these patterns. The Daneshgah neighborhood, characterized by greater vegetation density, exhibits higher climate resilience compared to Shirabad. Vegetation in Daneshgah enhances urban resilience by absorbing carbon dioxide, releasing oxygen, reducing ambient temperature, and improving soil water retention, thereby mitigating air pollution and urban heat island effects. Conversely, Shirabad’s compact built environment, inadequate infrastructure, and limited green space intensify its climate vulnerability. The findings underscore the critical role of effective green space management—particularly through the cultivation of drought-tolerant species, adoption of smart irrigation technologies, and establishment of urban green belts—in strengthening Zahedan’s urban climate resilience.