List of Articles geopotential height

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  1 - Analysis of Synoptic Patterns of the Two Heaviest Rainfall Events in Zayandeh Rood Dam Basin
  Shahideh Dehghan Amir Gandomkar Alireza Abbasi
  Precipitation is one of the most important climatic elements, and its importance increases especially when heavy rains occur. Investigating rainfall or heavy rainfall in a region requires analysis of synoptic patterns. This research was conducted with the aim of investi More

  Precipitation is one of the most important climatic elements, and its importance increases especially when heavy rains occur. Investigating rainfall or heavy rainfall in a region requires analysis of synoptic patterns. This research was conducted with the aim of investigating the heavy rains in the catchment area of Zayandeh Rood Dam. For this purpose, the daily rainfall data of Kohrang, Fereydon Shahr, Shahrekord, Daran, Pol Zaman Khan, Farrokh Shahr, Chadegan and Saman stations during the statistical period of 1958-2019 were used. After examining the data, two rainfall events on 7/1/2004 and 12/3/2005, which were heavy rains (rainfall above 20 mm) in the study area, were selected and their co-occurrence patterns were analyzed. The data related to geopotential height of three levels of 500, 700 and 850 hectopascals was obtained from the NOAA site and its maps were drawn in Arc Gis software. The obtained results showed that heavy rains occur in the studied basin when cold air in higher latitudes moves to lower latitudes and obtains the necessary moisture over the Red Sea and the Mediterranean. When the trough axis is located in the eastern Mediterranean and there is a lot of humidity, it causes heavy rains in the studied area. In general, it can be stated that the heaviest rains in the studied area occur in March and the Mediterranean and Sudanese systems cause heavy rains in this area. Manuscript profile
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  2 - Synoptic analyzing the occurrence of strong wind and dust storm in Shiraz in March 2019
  Ashraf Asadi
  As transition seasons approach at the end of the winter season, changes in movement patterns and wind speed in mid-latitudes are inevitable. On March 22, 2019, a strong wind accompanied by heavy dust and muddy rain for a large part of the day resulted in the injury of s More

  As transition seasons approach at the end of the winter season, changes in movement patterns and wind speed in mid-latitudes are inevitable. On March 22, 2019, a strong wind accompanied by heavy dust and muddy rain for a large part of the day resulted in the injury of several citizens and significant damage in the city of Shiraz. For this reason, this research was conducted with the aim of investigating the synoptic conditions of the formation of this phenomenon. Earth surface data from the Meteorological Organization and variables of air temperature, geopotential height, sea level pressure, zonal wind, meridional wind, specific humidity, and omega were used as upper atmosphere data to investigate the upper level of the atmosphere. Using these variables, geopotential height roughness map patterns, frontal formation process, vorticity advection, humidity, thickness pattern, earth surface pressure patterns, Jetstream, Omega, and Hof-Muller diagrams of the third type of Jetstream and Omega were drawn at different levels. The results showed that the location of the studied area under the positive advection zone in the east of the western wind channel, which leads to high divergence and low convergence, the establishment of temperature trend and front formation, and especially the descent of the polar front wind to the lower atmospheric levels, the conditions Synoptic have provided for the occurrence of strong air ascent and the formation of strong gusts caused by it. Manuscript profile
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  3 - A Synoptic Study of Heavy Rain in Southern Regions of Bushehr Province
  Amir Gandomkar
  Heavy rains are one of the features of arid and semi-arid climates which result in flood. This kind of rainfall originates from environmental and synoptic conditions. Mediterranean cyclones are the major factors in heavy rainfall in Iran, but these cyclones do not happe More

  Heavy rains are one of the features of arid and semi-arid climates which result in flood. This kind of rainfall originates from environmental and synoptic conditions. Mediterranean cyclones are the major factors in heavy rainfall in Iran, but these cyclones do not happen in some parts of Iran such as Southern and Southeastern areas. In this study, it has been tried to pinpoint the synoptic reasons of heavy rainfall in Southern regions of Bushehr province through the analysis of the relationship between this rainfall in Bushehr province and atmospheric system over Iran and the areas around it. The findings of this study show that the major cause of heavy and torrential rains is the arrival of Sudanese low pressure system in this region from the South and Southwest. Albeit, if the ascent local conditions such as heat occur, the heaviest rains happen in Southern regions of Bushehr province. In fact, this kind of rainfall in this area has a Sudanese origin and if it is accompanied by Mediterranean system, heavier rain falls. Manuscript profile
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  4 - Mahabad Spring Freezing Forecasting, Using Synoptic Study
  A, Gandomkar
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