Identifying tropical storms and determining storms and their paths have been challenging issues among climatologists. In one of the first studies on extraterrestrial storms, the frequency of tornado and anticyclone centers as well as the destruction centers of these atmospheric systems in the Northern Hemisphere was studied (Smagorinsky, 1950). Some early studies have shown that the North Atlantic Ocean, especially west and east of it, the North Pacific Ocean and the Mediterranean basin, especially during the cold period of the year, are the main tornado centers in the Northern Hemisphere (Withaker and Horn, 1984). . In early studies, a storm was manually identified and routed from synoptic maps, which was a time-consuming task (Flocas et al., 2010). However, due to the entry of computers into the world of science, automatic and machine methods made hurricanes objectively and intuitively identified and routed on digital maps (Ulbrich et al., 2009). Routing cyclones can be a useful tool to classify them based on their size (Rudeva and Gulev, 2007), their physical properties (Blender et al., 1997), and the degree of disturbance they cause in the atmosphere. Due to the lack of a single scientific definition of extraterrestrial storms, a large number of identification and tracking methods have been developed (Neu et al., 2013).
The first target method for Mediterranean storms was introduced by Alpert et al. (1990). In their study, they used ECMWF data based on monthly data for a 5-year period (1982-1987) to analyze storm frequencies and tornado tracks with low temporal and spatial resolution (12-hour temporal resolution and 2.5∘ spatial resolution). they used ). For this purpose, the minimum level of geopotential height of 1000 hectopascals was introduced with the interpolation approach to identify surface cyclones. For routing, the elliptical search area was used to determine the cyclone in the next step, whose main axis was determined using the 700 hPa wind vector. A gradient of 0.5 hPa at 500 km was determined as a criterion for identifying storms in four directions (north, south, east, and west) (Blender et al. (1997) from a two-step approach to identify mid-latitude storms and storm tracks in North Atlantic Ocean. The authors first considered the minimum geopotential pressure as a cyclone. This minimum pressure should occur on a 3x3 grid with a spatial resolution of 1.1x1. The positive slope was a height of 200 meters per 1000 km. After identifying the storms and clustering them using the k-means method, the storms were clustered in three types of storm tracks Their activity was mostly around the place of their formation. The second group of storms was identified as northeast cyclones. They moved east and west in a shorter spatial and temporal range and seemed to have a more limited regional activity.
In another study, Sinclair (1997) used ECMWF circulation data to identify and intuitively track bi-hemispheric storms, showing that they form and intensify in the Northern Hemisphere, near the eastern seaboard of Asia and North America. In the Southern Hemisphere, hurricanes form in mid-latitudes and in the oceans off the east coast of South America and Australia and break up in high latitudes. Mehmet et al. (2004) studied the variability of tornado tracks in Turkey and showed that the dominant tornado tracks are the tracks with the highest frequency of storms in winter. Picornell et al. (2001) identified and navigated western Mediterranean hurricanes for the period 1995–1999 at high resolution (0.5).
Sudanese low pressure systems are one of the thermal low pressures that form around the Red Sea, and their low pressure lines cover the south of the Red Sea, Sudan and Ethiopia, and continue their path from the southwest of Iran, causing heavy rains. The common feature of all These are rain systems, low pressure of the earth's surface or low altitude of the higher surface. For the dynamic and thermodynamic analysis of the mechanism caused by the Sudanese low pressure system, which has climate maps, wind, omega, Shum, slp, monthly mean surface tension in the north, daily mean precipitation and temperature since 1988. -2020 during. The cold season of the year was applied. The results show that the Sudanese low pressure core in 1999, 2006 and 2010. In this period, from the Sudan region to the high latitudes of Iran, the surface level of the north was of good potential. The study showed that the jet streams form rivers that originate in Africa and are strengthened by the Sudanese low pressure and can be transported to the upper atmosphere of Iran. Between the positive and negative omega lines, about 600 hectopascals, the horizontal moisture transport mechanism for Iran's rainfall is created by the atmospheric forces strengthened by the Sudan power source. A high slope in the isothermal lines in the hPa range of 550-850 also occurred on the same day.
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