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Statistical - Spatial Analysis of the Core of Siberian High Pressure System Period 1955-2014)
Daryosh Yarahmdi, Asadollah Khoshkish, Mustafa Karampour, Ismail Ahmadi,
Volume 16, Issue 40 (3-2016)
Abstract

One of the Siberian high pressure system is the Earth climate system, atmospheric important. The purpose of this study, analysis of core changes Siberian high pressure system in the period mentioned. To identify the core spatial variations in the timeframe mentioned data, daily sea level pressure and temperature of the earth's surface with a resolution of 2.5 degrees within the space of 30 to 65 degrees north latitude and 130 degrees east longitude from the database 45 to NOAA NCEP / NCAR for the cold was extracted. The core of the GIS spatial data analysis system and two separate zones and point to output six decades was ten years old and were analyzed. To study the process of change, determine the direction of the trend, type and timing of changes in temperature and pressure of the core of the system the test of Mann-Kendal is used. Comparison between the first and sixth decades 60-year period showed that the core in January from the East to the West and in October and March from the North East to the South West from the Balkhash Lake to Baikal there has been a significant shift. Results also showed that during the same period the Siberian High central pressure was reduced in January while the land surface temperatures in January showed a significant upward trend. Unlike the months of October and January, in March the central pressure had few mutations but no trend was observed. However, during this month the Earth's surface temperature has increased significantly during thementioned period.


A description on decadal changes in warm season average of precipitation over the Caspian coast of Iran territory
Dr Hossein Asakereh, Nasrin Varnaseri Ghandali,
Volume 22, Issue 64 (3-2022)
Abstract
Change in precipitation features is one of climate change outcome. Change in precipitation amount, especially in warm season, may influences climato-environmental phenomenon as well as human activity. In current research the decadal changes of monthly precipitation over the Caspian coast of Iran territory was evaluated. Accordingly, a large number of rain gauge stations (385 stations), where rainfall is measured painstakingly, have been used. these stations are under the supervision of Meteorological Organization of the country and Ministry of Energy. Since the original dataset pertaining to the precipitation prior to 1966 had noticeable missing values, and the data after 2016 were not accessible, a continuous time period from January 1966 to December 2016 was selected. From the daily precipitation of aforementioned stations contour maps were created using an ordinary Kriging method. The spatial resolution of these precipitation maps was 3 km * 3 km. Our finding showed that during the under investigation period the maximum gradient of precipitation moved from coastal parts toward mountainous area. Decrease in the area with high precipitation and increase in the low precipitation area is an other prominent decadal characteristics. According to the previous study, these changes might attributed to changes in systems which effect precipitation in the Caspian coast of Iran (northward movement in polar vortex, sub-tropical high pressure and cyclone truck). In addition, increasing temperature trends in the summer tend to decrease temperature spatial differences. Therefore, the convectional precipitation during summer has been decreased.

Modeling and predicting the trend of temperature changes in Hamedan County
Zohreh Maryanji, Fatemeh Sotoudeh, Meysam Toulabi Nejad, Ziba Zarrin,
Volume 25, Issue 77 (6-2025)
Abstract
Understanding and predicting future climatic conditions and characteristics is crucial due to their implications for various aspects of life. This research aims to forecast trends in extreme temperatures in the Hamedan region by employing statistical downscaling of general circulation model data. The LARS statistical downscaling model has been utilized to downscale data from the HadGEM2-ES general circulation model and the coupled CMIP5 model under three emission scenarios (RCP2.5, RCP4.5, RCP8.5). Correlation estimates between the simulated and observed data indicate values exceeding 0.95 for all months. Additionally, the p-values derived from statistical tests based on the model outputs demonstrate an acceptable level of performance in data generation and simulation. Consequently, data from 2011 to 2050 were extracted and analyzed for trends. To elucidate changes in trends, the data were examined across three distinct time intervals. The results indicate that in the optimistic scenario (RCP2.5), no significant trend is observed in the average and minimum temperatures. In contrast, significant trends in temperature data are evident under the RCP4.5 and RCP8.5 scenarios, suggesting that the increase in average minimum temperatures reflects severe climatic changes, particularly affecting precipitation patterns during the cold season. Furthermore, the analysis of the trend data reveals a significant increase in average maximum temperatures on both annual and monthly scales across all three examined scenarios, indicating an imminent environmental crisis.

Sustainable Regeneration of Neighborhoods and Reform of Urban Poverty Structures with a Futures Research Approach; Case, Worn and Inefficient Textures of the Ahvaz Metropolis
Ph.d Khalaf Anafjeh, Se Yyed Mehdi Moussakazem, Ph.d Masoud Safaipour, Ph.d Abdulnabi Sharifi,
Volume 25, Issue 79 (12-2025)
Abstract
This article aims to identify and analyze the five strategic drivers of the urban poverty system in the target neighborhoods of the study. These drivers can be effectively managed, manipulated, and tracked through the implementation of anti-poverty policies, thereby improving the overall condition of these neighborhoods. Recognizing the critical need to organize economically-focused spaces, the article seeks to reform and reconstruct the urban poverty structures in the target areas through a futures research approach. The research is applied in nature, utilizing a descriptive-analytical methodology that aligns with contemporary normative futures research practices. Following the development of a questionnaire for equilibrium analysis of interactions, a comprehensive assessment of potential states and their classifications (uncertainty scenarios) was conducted. This enabled the extraction of qualitative insights from 30 experts regarding the interrelationships within the network, facilitated by a Delphi survey and algorithmic data analysis using the CIB method in the Scenario Wizard software.Given the matrix size of 15x15, the Scenario Wizard software analyzed 3,657 combined post-scenarios based on the questionnaire data, yielding five strong or probable scenarios, 14 high-compatibility scenarios (believable scenarios), and 28 weak scenarios (possible scenarios). After expert validation, four scenarios were descriptively named: M-A, M-Sh, H-HA, and Z-S.J. Finally, by employing thematic macro-trends as technical tools for future-oriented economic interventions in the regeneration process, tailored poverty alleviation policies were formulated and proposed for each driver, presented as thematic measures based on the desired scenarios to reform the urban poverty structures of the Ahvaz metropolis.

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