scholarly journals Monitoring DSI and Lancaster Indices for Study Dust and Sand Storm In Meteorological Mehrabad Station of Tehran

2021 ◽  
Vol 11 (2) ◽  
pp. 30-42
Author(s):  
Rahman Sharifi ◽  

The first climatic factors affecting the phenomenon of dust and fine dust are collected, reconstructed, extended and completed in the form of DSI (Dust Storm Index) and Lancaster in Mehrabad meteorological station of Tehran was studied and analyzed. The results showed that in Mehrabad meteorological station in terms of temperature in 1992 the lowest value and in 1998, 2001, 2017 the highest value and in terms of humidity in 2017 the lowest amount of humidity and in 2000 the highest amount of humidity and in terms of rainfall in the year 2013 the lowest amount of precipitation and in 2019 the highest amount of precipitation and in terms of evaporation in 2009 the lowest amount of evaporation and in 1391 the highest amount of evaporation and finally in terms of number of dust days in 1998 the lowest number of days and in 2009 the highest number of days Dust has been recorded. Mehrabad station of Tehran in years showed DSI index, more than one number and Lancaster index, more than fifty number in most of the mentioned years, the values of temperature and evaporation are high and the values of precipitation and humidity are relatively low, which shows the direct relationship between the dust storm index (DSI index) and mobility index of sand dunes (Lancaster index) is almost too high and above the number, It is noteworthy that in most of the mentioned years, Meteorological factors and data have been at Mehrabad station in Tehran.

2020 ◽  
Vol 54 (1A) ◽  
pp. 69-83
Author(s):  
Muaid Rasheed

The study deals with the geological situation of Earth's features, and the effect of climate on them, through monitoring changes that have occurred in Earth's features by applying supervised classification represented by maximum likelihood classification using GIS 10.7 for years 1990–2019 to produce maps of desertification and sand dunes encroachment. The factors forming the Earth's features in the study area vary due to the geological structure, geomorphological processes, and climatic factors, which requires an analysis of these processes and their impact on environmental components. The climate of the study area is characterized by continental characteristics causing significant differences in the geomorphological units of the region, especially sand dunes. The most important climate factors affecting the desertification and dunes are the temperature, evaporation, wind speed and rainfall. Three satellite images were used in this study, obtained from Landsat 5-8 besides, the rate annual of temperature, evaporation, wind speed and the total annual of rainfall obtained from European center ECMWF. To obtain high accuracy of classification, an Error Matrix and Kappa Coefficient was processed using ERDAS. The results showed clear changes in the Earth's features with climate during the entire period, where the increase in the rate of temperature and evaporation enhances desertification and encroachment of dunes due to the dryness of the area resulting from the decrease in rainfall rates due to the lack of vegetation growth, as the area of desertification increased to 3028 km2 in 2019, compared with 1990, while the area of dunes double, in the year 2019 compared to the year 1990. dune encroachment changed directly with the winds as a result of wind blowing in a northwestern direction, so the dunes expanded in the south and southwest direction at the expense of cultivated areas as they encroachments by 20 km compared to 1990.


Hacquetia ◽  
2014 ◽  
Vol 13 (1) ◽  
pp. 171-189
Author(s):  
Georgios Fotiadis ◽  
Michael Vrahnakis ◽  
Yannis Kazoglou ◽  
Ioannis Tsiripidis

Abstract A recently completed project on the Natura 2000 sites of Prespa National Park revealed that the area hosts 49 habitat types according to the EU classification, of which eight have a narrowly restricted distribution in Greece. The priority habitat type “*6260 Pannonic sand steppes” is reported here for the first time for Greece. The new locality represents its southernmost occurrence on the Balkan Peninsula. The aim of this paper therefore is to describe the Greek stands of this habitat type, investigate the factors affecting its occurrence and discuss the associated conservation issues. This is based on a total of 87 releves sampled for this study and 8 additional releves from the literature. The releves were classified by applying TWINSPAN and ordinated using Detrended Correspondence Analysis (DCA). Six vegetation units could be distinguished. One of these corresponds to the habitat type *6260 and was found exclusively on inland sand dunes. Syntaxonomically, we assigned this unit to the alliance Sileno conicae-Cerastion semidecandri s.l. of the class Koelerio-Corynephoretea. Its occurrence in the study area seems to be determined by climatic factors, as well as by the sandy substrate, while anthropogenic disturbances such as grazing also appear to be beneficial to some degree. Apart from the Koelerio-Corynephoretea, another five grassland classes were distinguished in the national park, namely the Thero-Brachypodietea, Stellarietea mediae, Festuco-Brometea, Daphno-Festucetea and Juncetea trifidi.


Author(s):  
Nikolaj Dobrzinskij ◽  
Algimantas Fedaravicius ◽  
Kestutis Pilkauskas ◽  
Egidijus Slizys

Relevance of the article is based on participation of armed forces in various operations and exercises, where reliability of machinery is one of the most important factors. Transportation of soldiers as well as completion of variety of tasks is ensured by properly functioning technical equipment. Reliability of military vehicles – armoured SISU E13TP Finnish built and HMMWV M1025 USA built were selected as the object of the article. Impact of climatic conditions on reliability of the vehicles exploited in southwestern part of the Atlantic continental forest area is researched by a case study of the vehicles exploitation under conditions of the climate of Lithuania. Reliability of military vehicles depends on a number of factors such as properties of the vehicles and external conditions of their operation. Their systems and mechanisms are influenced by a number of factors that cause different failures. Climatic conditions represent one of the factors of operating load which is directly dependent on the climate zone. Therefore, assessment of the reliability is started with the analysis of climatic factors affecting operating conditions of the vehicles. Relationship between the impact of climatic factors and failure flow of the vehicles is presented and discussed.


1998 ◽  
Vol 31 (9) ◽  
pp. 13-18 ◽  
Author(s):  
Levent Şaylan ◽  
Hasan Tatli ◽  
Zekai Şen

2014 ◽  
Vol 36 (2) ◽  
pp. 185 ◽  
Author(s):  
Fang Chen ◽  
Keith T. Weber

Changes in vegetation are affected by many climatic factors and have been successfully monitored through satellite remote sensing over the past 20 years. In this study, the Normalised Difference Vegetation Index (NDVI), derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Terra satellite, was selected as an indicator of change in vegetation. Monthly MODIS composite NDVI at a 1-km resolution was acquired throughout the 2004–09 growing seasons (i.e. April–September). Data describing daily precipitation and temperature, primary factors affecting vegetation growth in the semiarid rangelands of Idaho, were derived from the Surface Observation Gridding System and local weather station datasets. Inter-annual and seasonal fluctuations of precipitation and temperature were analysed and temporal relationships between monthly NDVI, precipitation and temperature were examined. Results indicated NDVI values observed in June and July were strongly correlated with accumulated precipitation (R2 >0.75), while NDVI values observed early in the growing season (May) as well as late in the growing season (August and September) were only moderately related with accumulated precipitation (R2 ≥0.45). The role of ambient temperature was also apparent, especially early in the growing season. Specifically, early growing-season temperatures appeared to significantly affect plant phenology and, consequently, correlations between NDVI and accumulated precipitation. It is concluded that precipitation during the growing season is a better predictor of NDVI than temperature but is interrelated with influences of temperature in parts of the growing season.


1961 ◽  
Vol 41 (1) ◽  
pp. 199-203 ◽  
Author(s):  
A. C. Carder

In a 3-year free-water evaporation study, an evaporimeter tank in the open field lost 34.5 per cent more water than a tank sheltered by buildings and trees. Meteorological factors responsible for this difference appear to be high wind velocities and long daily periods of sunshine. Changes in temperature regime had no effect.Difference in evaporation from the two tanks led to examination of data obtained over 35 years from the sheltered tank. It was found that, although there was a progressive decrease in amount of evaporation over the years from this tank, rainfall at the same time had increased and that the effect of this increase on evaporation was roughly equal to that of all other factors affecting evaporation, such as a change in exposure, etc. Thus, the comparatively low rate of evaporation from the sheltered tank was undoubtedly due in part to the proximity of buildings and trees which had been established.


10.5109/4636 ◽  
2005 ◽  
Vol 50 (1) ◽  
pp. 189-199
Author(s):  
Eduardo Jimmy Pua Quilang ◽  
Taichi Maki ◽  
Mingyuan Du

2020 ◽  
Vol 37 (2) ◽  
Author(s):  
Claudia Patricia Criollo-Velásquez ◽  
Johana Alixa Muñoz-Belalcazar ◽  
Tulio César Lagos-Burbano

The determinant factors of coffee cup quality are highly variable and depend on their interaction with coffee production and benefit. This study aimed to analyze soil and climatic factors and their association with the cup quality of Castillo coffee variety of three to five years of age from production units in ecotypes 220A and 221A of the Department of Nariño. The study farms were located in three different altitudinal ranges: ≤1500 m, between 1501 and 1700 m, and >1700 m. Soil, climate, and coffee cup quality variables were analyzed through principal component analysis and cluster analysis. A low level of association was found between climatic and soil nutritional factors and coffee cup quality. Soil Mn, Fe, and Cu contents showed the highest association levels with cup quality, indicated by an average score of 80.89. The highest values of photosynthetically active radiation -PAR- and thermal amplitude were found in La Unión - Nariño, and these variables were associated with the group that obtained the highest cup quality score (82.58). Cup quality was not associated with elevation since the highest scores (85.5 and 82.33) were obtained from production units located at ≤1500 m.a.s.l. and >1700 m.a.s.l, respectively.


2019 ◽  
Vol 31 (5) ◽  
pp. 1248-1258
Author(s):  
LUO Xiaochun ◽  
◽  
HANG Xin ◽  
CAO Yun ◽  
HANG Rongrong ◽  
...  

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