Search published articles

Showing 5 results for Frost

Hassan Lashgari, Farshad Pajoh , Mohammad Bitar, Farzaneh Jafari,
Volume 2, Issue 1 (4-2015)

The temperature as an indicator of heat intensity is one of the basic elements of knowing weather. The frost is a condition when the air temperature is less than 0 c Due to the geographical possition of Iran, spring is a season that plants resume a new life after leaving a pause in a periode of the growth. At the beginning of such a periode emerge of sudden cold cause loss bloom (in the case of openinig) or delay in a beginning of plant growth periode (Azizi,2002). Recentley with occuring climate chaos, one of the important climatic disasters which treats human and particularly different  areas of the country are cold waves and sever frosts that in some years covers large area of the country.

    Surface data including minimum daily temperature of the days of 29 to 30 and 25 to 26 of march of 2003 and 2005 in 9 meteorological synoptic stations in the area of north west of Iran in  table (1) was collected  from meteorology organization then the days of cold waves in the above mentioned time periode, were analyzed. In ordet to analyse the synoptic patterns, using ncep/ncar data, maps of sea level pressure ,combined of  geopotential height and vorticity and temperature advection  using Grads were drawn and analysed in the levels of 1000 to 500 hpa.
    As it mentioned, during the time period, 29 to 30 and 25 to 26 of the march in 2003 and 2005, 2 clod system  were located on the area of north west. In oeder to explain and analyze of  synoptic patterns of  mentioned period time, the absolute minimum temperature below 0 degrees celsius of stations in western Azarbayejan province were selected and maps of sea level pressure, combined of  geopotential height and vorticity and temperature advection  using Grads were drawed and analysed in the levels of 1000 to 500 HPA. 
     The results showed that in the time of occuring hazardous cold waves of  29 to 30 of march 2003 and 25 to 26 of march 2005 and analyzing the sea level map in the first day of cold wave with spreading the cold core high pressure  from the eastern Europe and its location on north and east north of the black sea and its pentration from north west corner of the country covered most of the areas of the country. 
    Analyzing the combined maps of geopotential height and vorticity in the levels of 1000 and 850 HPA in the first day of occurrence of  cold, generaly faced with huge anticyclonic development . But in the levels of 700 and 500 HPA , the under studied area was in the south trough of the obtained cold core of the low height locating in the cetral Asia. But on the day of cold peak, high pressure core was exactly located on the under the studied area . Also in the upper levels of atmosphere with locating the back of the trough cumulated  of cold air of upper width on the sea level high pressure centre while strengthening the lower levels anticyclonic flows, led to intensifying cold and frost in the west Azarbayejan province. 
Positive and negative vorticity maximum cells, also conformed the intensity cold circulation flows on the north half of the country in anticyclone and cyclone centers in order. Also analysing the temperature advection in the levels of 1000 to 500 HPA, direction and temperature intensity exactly followed geopotential height maps patterns. 
     Such that in the levels of 1000 hpA of the both cold wave analysed, the anticyclonic cold temperature adcection and northward is located on the north west of the Iran. In temperature advection maps of 29 and 30 march 2003 in 850 HPA in Azarbayejan province, the anticyclonic circulation is matches with sea level high pressure. But in the 2nd cold wave that’s occured on 25 and 26 march 2005, the north west area is between 2 antycyclonic circulation on Mediterranean and cyclon located on south of  Russia that the directions of temperature cold flows is completely north ward in this level. 
    In the temperature advection maps of 700 and 500 HPA, the Azarbayejan province is in the western edge of central Asia trough or south of Russia. 
    The results showed that with studying  atmospheric motions and synoptic systems which create cold flows, we can prevent of spring late  emergence cold wave destructive impact on agricultural products, energy consumption, and road accidentd by  forcasting of these atmospheric conditions.

Neda Kazemi, Maryam Sharifzadeh,
Volume 3, Issue 1 (4-2016)

Frost is one of the sources of risk in agriculture which threatens the orchardists' performance and their security of products. The protection of cold-sensitive species of fruits against frost damage is an annual challenge in many growing regions of the world. Frost protection managerial behavior is the the first way to avoid or reduce the effects of frost damage to walnut trees. Application of active and passive methods of frost protection is effective under conditions of strong thermal inversions. However, most of studies on the adoption of managerial behaviors to environmental hazards usually ignore underlying psychological constructs that affect farmers’ decisions and behavior. Sepidan county is one the well-known regions of Fars province which is subjected to frost damage for its climatic nature. The amount of frost damage to walnut orchards of Komehr township, which is located in Northwest of Sepidan county is significantly substantial in recent years. The region is well-known for its walnuts and this product is the most important source of velliagers’ income. This research aims at investigating frost management behavior of walnut orchardists of Sepidan county, Fars province, Iran. The managerial behavior is composed of active and passive methods of protecting walnut trees to frost damage.

This applied study was based on descriptive correlational method. Data collection tools were structured questionnaires. The sample of this survey study was consisted of 90 orchardists of Komehr township. The sample orchardists were selected based on their vulnerability against frost. Structured questionnaires were used to collect information from a random sample of walnut orchardists that were interviewed. Face validity was confirmed by a panel of experts. And the reliability was confirmed by conducting a pilot study in Bardzard region. The calculated Cronbach’s alpha for the measures of the instrument were 0.53-0.82. Statistical package for social science (SPSS) in WINDOWS context was used for analyzing data. Coefficient of variation and cluster analysis was the most important analysis methods applied in this research.

Results revealed that active methods of frost protection includes burning fuel, tires etc., were the most common methods of controlling frost in walnut gardens. While using energy intensive practices (heaters, sprinklers) were shown the lowest rate of interest. However, orchardists' "perceived effectiveness", "perceived ease of use" and "perceived usefulness" of their active and passie controlling behavior was investigated. As it was shown by the results, orchardists' perception of effectiveness of the method of controlling frosts was in a low position. On the other words, they were not belived in the effectiveness of the methods. This was whilst, orchardists belived in ease of using the active and passive measures of controlling frost. They were noted that these methods had the potential of controlling damage to their gardens. Performing frost controlling methods was not easily applicable and garden's context was known as the most important barrier to performing the frost controlling behavior. To better understand orchardists' profile regarding to their frost protection behavior, cluter analysis was used. By means of this method, orchardists were categorized to two clusters: orchardists with convergent behavior with respect of frost protection protocol and divergent ones. Convergent group of orchardists (n=23, 25.5 %) were those who invested more on their gardens, used crop insurance supports, and more importantly they used lower levels of chemical products (poisons, fertilizers, etc.) on their gardens. On the other hand, divergent system of gardening regarding to frost protection pointed to the system of negative orientation towards rational thinking and behavior of gardening protection. These group of orchardist (n=67, 74.5%) were those who were performed eclologically dangerous methods of gardening regarding to use of pesticides, fertilizers and other chemical inputs. Low level of orientation towards crop insurance organizations and investment for the gardens were the most differtation factors for this group. However, results shed light on the difference of these two groups of orchardists regarding to their percievd effectiveness, ease of use and usefulness of frost protection methods. As it was shown by the results, frost protection- conevergent group of crchardists was significantly different from their divergent counterparts regarding their frost protection behavior and perception of ease of use and usefulness of frost protection methods. The aforementioned group of orchardists perceived frost protection methods easy to perform. From their viewpoints, these methods were useful in increasing crop yield, promoting its quality and controlling damge.      

, , , ,
Volume 5, Issue 4 (3-2019)

 Extended  Abstract
Cold and frost is one of the most important climatic parameters in the agricultural climate, and the damage caused by them reduces the possibility of producing many agricultural and horticultural products in vulnerable areas. Cold and frost is one of the climatic hazards that annually causes damage to various activities. The agricultural sector is the most important part of the damage that is most seriously damaged by frost. Cold and frosty weather for many crops and gardens results in harmful and destructive consequences, in some years billions of rials damage farmers, farmers and, ultimately, the national interests of the country. Considering that the northwest region of Iran suffers a lot of financial losses each year due to atmospheric hazards especially cold and frost. Identification and zoning of areas with high potential of cold and frost hazard and prediction of their occurrence can provide valuable and valuable information for preventing and mitigating damages. In this study using HadCM3 global model under two scenarios A2 and B1 and The LARS-WG microscope model is dealt with this.
It is important to check the time of occurrence and predict their future changes. For this purpose, general atmospheric circulation (GCM) models are designed that can simulate future climate parameters. In this study, the output data of the HadCM3 general circulation model under two scenarios of A2 and B1 were analyzed by LARS-WG statistical method in 21 synoptic stations located in northwest of Iran. The results of this study were based on the base period (1980-1989) and The 2020 decade (2030-2011) was evaluated for two climate variables: minimum temperature and maximum temperature. Then the history of the first and last frost and cold of autumn and spring was extracted and their date of occurrence was calculated in the future.
The monthly average of the minimum temperature of the stations studied in the course of the 2020s and the base period shows that the temperature has been increased according to both scenarios and increased in all months and at most study stations compared to the base period. The maximum changes in the minimum temperature in the study area are based on the average scenarios in this decade related to Abhar, Ardebil, Khoy and Urumieh stations at 0.8 degrees Celsius; In fact, the minimum temperatures that occurred at these stations during the base period have not been observed in the next period and the heating process has shown that its rate in the region of the study area in the 2020s is between 0.4 and 0.8 It will be in the base period. The results indicate an increase in the monthly average of the minimum and maximum daily temperatures in the upcoming period to about 0.8 degrees Celsius. The results of the first and last glacial survey in the decade of 2020 indicate that the first glacial precipitate of autumn occurs between 2 and 9 days later, with the least change in the history of frost occurring in two stations of Qazvin and Meshkinshahr each with 2 The change day is relative to the base period. The last frost of late spring also will be 3-10 days earlier on the surface of the region. However, the duration of the ice free period will be reduced at all stations, which is the highest decrease for Khoy station with 16 days, then the stations of Urmia and Ardebil each Two with 14 days and the lowest decrease is due to Meshkinshahr station for 6 days. Based on the results of changes in the date of early ice ages, changes are less than the late frost. Based on this, the study of the condition of glaciers and serma in most of the studied stations shows that the first frost and autumn frost in the coming period will start earlier and the cold and the frostbite will end sooner. The least changes were observed in the south-east of the study area, Meshkinshahr and Sarab regions, and the most changes in the glacial period were related to Khoy, Urmia, Tabriz and Ahar areas. According to the results of most studied areas, averaging between 10 and 12 days decrease in length The ice age will experience the base course.
The results indicate an increase in the monthly average of the minimum and maximum daily temperatures in the upcoming period to about 0.8 C. Based on this, the study of the condition of glaciers and serma in most of the studied stations shows that the first frost and autumn frost in the coming period will start earlier and the cold and the frostbite will end sooner. Also, the length of the cold and freezing period is decreasing, which may reflect the consequences of climate change at study stations. The results of this study are based on the studies of Grasick and Dodwilich (2015) in Poland, Medella et al. (2016) in Texas, Hosseini and Ahmadi (1395) in Saqez, Aqa Shariatmadari et al. (1395) in West Iran, Sobhani et al. (1396). ) In Ardebil and Khalili et al. (1396) in Iran.
Mr Ali Hasanzadeh, Mr Hooshmand Ataei, Mr Nader Parvin, Mr Amir Gandomkar,
Volume 6, Issue 1 (5-2019)

Agricultural crops have damaged a lot due to the aftermath of late spring frost, and because low temperatures have damaging effects on agricultural production, it is essential to anticipate and prevent potential damages. Often, atmospheric temperature variations are very urgent due to the high temperature of the systems and the plants cannot adapt themselves with severe oscillations and, have been damaged. The aim of this study was to analyze the climate of the spring frost in Kermanshah, identifying the sea level equations and the late spring freezing frost of the period from 1990 to 2015. This survey has been done to determine the period of the freezing phenomenon, determine the minimum daily temperature of 7 stations placed in Kermanshah,  Hamedan, and Ilam. After analyzing the data of spring frost freezing of Kermanshah province using the main component analysis technique and hierarchical clustering method, the most common 10 patterns of late spring coldness of the area were studied and determined. In 10 resulting cluster, 8 clusters were related to the high-pressure pattern of Siberia. From the total 91 days of spring frost freezing in Kermanshah province (79% (72 days)) is due to the high rainfall of Siberia, 12% (11 days)  is due to the Mediterranean climate and 9% (8 days) is due to the Van lake climate. These pressure patterns were named according to the location of their deposition, which caused the loss of the environment and the freezing frost of the spring.
Dr Raoof Mostafazadeh, Vahid Safariyan-Zengir, Khadijeh Haji,
Volume 8, Issue 4 (3-2022)

Road accidents is the outcome of driver behavior, road condition, vehicle status, and environmental factors. Therefore, identification and assessment of effective parameters on road accidents can be considered as an appropriate way to reduce the accident events, driving violations and increase the road safety. Determining the effects of meteorological factors on the road accident events has gained more attention in recent years.
  The The main objective of this study was to investigate the relationship between the number of road accidents and the meteorological variables in the intercity road of Grmi-Ardabil in the Barzand route.
In this regard, the effects of climatic factors (including rainfall amount, the minimum absolute temperature, and the number of frost days) on the frequency of perilous events were analyzed. The data of accident events (in recent 4 years) were obtained from the trooper department of Ardabil Province along with the meteorological parameters of Germi station through a 11-year period. The statistical tests were performed using R programming software through statistical analysis.
Findings and Discussion:
The results showed that the majority of accidents were occurred in winter season which is in consistent with the frequency of frost days and also corresponded to the absolute minimum temperature. According to the results, the highest significant positive correlation at (R2= 0.43) was observed between the number of injured people and frost days. In addition, the relationship between the absolute minimum temperature and the number of were identified as significant negative correlation.
As a concluding remark, the poor road conditions caused by climate element can be considered increasing the frequency of accident events. Accordingly, the proper strategies related to behavior change could be
considered in setting the rules and regulations to reduce the accidents and the number of injuries.

Keywords: Climatic hazards, Correlation analysis, Frost days, Minimum absolute temperature, Germi-Ardabil road


Page 1 from 1     

© 2024 CC BY-NC 4.0 | Journal of Spatial Analysis Environmental hazarts

Designed & Developed by : Yektaweb