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  Extreme precipitation is one of the climatic risky behaviors that are associated with abnormalities and environmental-human consequences. This study has investigated daily rainfall  of 20 rain gauge and synoptic stations over 30 years (1987-2016) in the West of Gilan province, to determine the trend of extreme precipitation changes. In this regard, non-parametric Mann-Kendall test, Sen's Estimator slope, Poisson distribution, and IDW interpolation have been applied, respectively, to determine the existence of trend, significance, to determine the probability of rainfall occurrence   and to identify spatial patterns of precipitation occurrence with different probabilities. The results suggested an increasing trend in Astaneh-ye Ashrafiyeh, Bandar-e Anzali, Masuleh, and Astara and an extreme decreasing trend in Bash Mahalleh due to the Mann-Kendall test. Studying the significance or insignificance of changes trend by Sen indicated that this trend has been significant in Mashin khaneh, Bash Mahalleh, and Punel Stations; and the null hypothesis, that is, the insignificance of change, was rejected. Sen's Method revealed that there were no significant changes in other stations, and their randomization will be confirmed. To this end, the spatial probability distribution of  to  indicate kernel probability displacement for different x.  The maximum probability to various occurrences has been at Masuleh station and Poisson distribution is a proper assessment of precipitation in this region.
 

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One of the main reasons for the occurrence of landslides is the mismanagement of the earth, especially in mountainous regions and valleys. In this research, we tried to investigate the factors affecting the occurrence of landslides and also comparing sections of Kuhdasht city in terms of landslide susceptibility in the form of multi-criteria decision making method (ELECTRE-1), areas with high risk of landslide hazard. The application of multi-criteria electric methods is in the ranking. The model (ELECTRE-1) evaluates the decision matrix, which includes m options and n indexes. In this research, the choices, parts of the city of Kuhdasht, and indicators are the factors influencing the occurrence of landslides. After weighing, comparing the pair and calculating the final weight of the factors, it was found that the gradient factor with a weight of 0.379 and a petrology with a weight of 0.248 have the main role in the sensitivity of the study area. The area was also assessed for the extent of the vulnerability to landslide. According to this assessment, Tarhan and Romeshgan sections (with the number of domination 2) have the highest risk for the occurrence of landslides and then, respectively, sections of Kohnani (with the number of domination 1), the Darbe gonbad and Central (Without the number of domination). The average weight of the factors according to the harmonized criteria is for the sections of Tarhan (0.427), Romeshgan (0.0412), Kohnani (0.359), Darbe gonbad (0.0253) and central (0.217). Among the factors that cause the sensitivity of the parts of the Tarhan and Romeshgan, the percentage of sensitive slopes (15 to 45 degrees), the petrographic situation (with the overcoming of lime and marl), the use of inappropriate land and hydrographic network can be mentioned.

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Abstract
One of the factors that sometimes leads to the complete destruction of vineyards is the danger of temperatures below zero degrees Celsius. The purpose of this study was to investigate the effect of temperature hazards on the destruction of the western and northwestern vineyards of Iran.The results show that the most frequent days with a devastating cold wave in the region's vineyards occur on average on January 14 (January 25th). The lowest critical temperature among meteorological stations is related to Saghez weather station in Kurdistan province with negative 33 ° C and afterwards, Hamadan, Bostanabad and Sarab cities with record temperatures below 30 ° C. The cities of the study area are. The results showed that 60% of the studied cities with all available Iranian and foreign cultivars could survive the cold season without the threat of severe winter cold conditions.
Key words: Grapes, winter cold, west and northwest
 
Introduction:
Grapes are warm and resistant to temperate zone plants, but despite the resistance of different grape varieties to cold, the resistance to cold in the hair is the same ability of the grape's sleeping tissues to survive under freezing stress conditions. It is autumn and winter, sometimes due to temperature stresses and unexpected damages(Jalili Marandi, R, 2010: 918).Rezazadeh and Alijani (2017)­, Synoptic analysis of the damaging cold waves of northwestern Iran. The results of this study showed that their monthly abundance is in the transition months of November and April and these two months have experienced more severe and pervasive cold waves than the other months. Mahmoudi (2016),  A study of the mean atmospheric circulation leading to widespread glaciation in Iran showed that in the circulation pattern of sea level pressure, the spatial arrangement of the Siberian high-pressure system and its interactions with the two polar low pressure systems (low pressure Iceland) and low pressure Sudanese monsoon is the most important push players in the maximum and minimum incidence of frosts in Iran.
 
Material & Methods
The study area includes West Azarbaijan, East Azarbaijan, Qazvin, Hamadan, Zanjan, Markazi and Kurdistan provinces. The climate of this region is mostly from the semi-arid climates and other climates in the region. The data used in this study include the minimum temperature parameter of 85 synoptic stations in the west and northwest of Iran during the period 1996 to 2014. It is also used to identify synoptic patterns (low and high pressure) and effective factor. The extreme cold and the time of its occurrence in the region have been analyzed by synoptic (synoptic) cold wave on January 14th. For this purpose, three hourly statistics of 85 synoptic stations during the period 1996 to 2014 were studied to determine the frost occurrence in the region and then the most frequent day, and the most frequent minimum temperature below 15 ° C, were determined.
Discussion & Result

Statistical analysis of minimum temperatures below -15 ° C that showed destructive temperatures in grape cultivars in western and northwestern Iran after Saghez in Kurdistan province with negative 33 ° C, Hamadan, Bostanabad and Hamadan Mirages are at temperatures below 30 degrees Celsius. Bostanabad, Kheirabad, Sarab; Zarineh Abatoo, Kamijan and Hamadan stations with mean of 15.8, 14.2, 11.3, 9.4, 8.7 and 8.4 days in one year, respectively, with the most days with Negative temperatures are 15 ° C and lower.Khendab stations with a temperature of 24.8 ° C and the cities of Bostanabad, Khoy and Hamadan with temperatures below 20 ° C have the most frequent temperatures below 15 ° C. Khandab city, in addition to its higher altitude, due to the dry and semi-arid climate and lack of sufficient humidity to reduce the effect of cold air transmitted along with the entry of cold-glacial waves from all stations in more critical condition contract .The analysis of the synoptic maps of January 14, as the average of the most frequent day of the lowest minimum temperature in the region, indicates that the orbital component is positive and the meridional component negative. Such conditions increase the intensity and magnitude of the extremely cold winter time in the region.
Conclusion:
Examination of the 500 hPa surface pressure map on high cold days such as January 21, 2007 shows that by observing the status of Azores tropical high pressure, Siberian surface thermal high pressure, and Iceland polar low pressure In addition, observations of 1022 hPa at ground level and 5520 hPa at 500 hPa can be predicted at least 1 to 3 days before the cold wave transporting critical temperatures to northwest, western and central parts of Iran. It provides farmers with the opportunity to prepare and provide the equipment needed to prevent and deal with the damaging cold wave.From a temporal point of view, the mean temperature distribution map for the late cultivar can be seen as a result of the close proximity of the phenological stages of fruit formation to the arrival and harvesting of cooler months (especially at lower temperatures at night). It is not suitable for the growth of diseases such as fungal infections of superficial white matter.
 

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Soil is the bedrock of life and economic and social activities, biological and biological diversity. Lack of statistics and information on soil erosion and sediment production in many catchments of the country necessitate the application of appropriate methods and models for estimating the severity of soil erosion and sedimentation. In this study, using the BLM Erosion Estimation Model and ElectRE-1 Multi-Criteria Decision Making Method, the erosion rate in the Romeshgan basin has been investigated and the erosion intensity and zoning map has been prepared. Results of applying ELECTRE-1 model show that topographic factor (slope) with weight of 0.5578 is more effective than other factors in basin erodibility and plays the main role. Also based on this model, sub-basin 1 in the north of the basin had the highest vulnerability to erosion and then sub-basin 2, 4 and 3, respectively. Using the BLM model, it was found that the low erosion class in the Romshgan catchment covers the most extent and then there are high, very high, moderate and minor erosional classes. In general, the area has moderate erodibility. The overlap of the layers indicated that the maximum erosion intensity was in the slopes and mountain units, which included new and old alluvial deposits and cone deposits, marl, lime, siltstone, sandstone, conglomerate and gypsum. Also, rainfed agriculture units have the highest intensity and forest and pasture units have the least amount of erosion. In terms of slope factor, lands with slope of 8 to 30 percent have the highest degree of erosion.