List of Articles Modis

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  1 - Investigating the drought index based on satellite images and its relationship with the reduction of the area under rice cultivation, a case study: (Ghamas province, Iraq)
  Ali Nik ahd Wathq  Ahmad almatlak ali ebrahimi
  Introduction: Using indicators based on remote sensing, drought can be studied through its effects on crops and more accurate and effective results can be obtained. The severe drought conditions in the entire country of Iraq have caused the farming communities to witnes More

  Introduction: Using indicators based on remote sensing, drought can be studied through its effects on crops and more accurate and effective results can be obtained. The severe drought conditions in the entire country of Iraq have caused the farming communities to witness a decrease in the harvest of rice, vegetables and fruits for the tenth year in a row. Therefore, farmers have to reduce the area under cultivation, which causes a decrease in their income and products. Ghamas province in Iraq is one of the regions that has rice cultivation lands and is suffering from drought. Therefore, this research has investigated the changes in the surface coverage under rice cultivation in this province and its relationship with the surface temperature in order to investigate drought Materials and Methods: In this research, the Normalized Difference Vegetation Index (NDVI) related to the MODIS sensor was used to study the changes in vegetation cover. MODIS satellite data were prepared and collected for the study area during the years 2010 to 2022. Next, three remote sensing indices, NDVI, Vegetation Condition Index (VCI) and Land Surface Temperature (LST) were used to investigate the area under rice cultivation as well as land surface temperature and drought severity. Results and Discussion: According to the obtained results, the cultivated area of agricultural products has increased during this period in the studied area, so that in 2010 the area under cultivation according to VCI and NDVI indices is 11875 ha and 10337 ha ,respectively, while in 2022, it increased to 14775 ha and 13275 ha, respectively. The results showed that according to the NDVI, vegetation cover with a gentle slope had an increasing trend during this period, while according to the LST result, the land surface temperature decreased during this period. This shows that with the increase in vegetation, LST has decreased. Conclusion: The results showed that according to the NDVI index, the vegetation cover had an increasing trend during this period, while according to the LST index, the surface temperature of the earth decreased during this period. This shows that with the increase in vegetation, the surface temperature of the earth has decreased. However, according to the VCI index, the studied area is in a non-drought condition. Therefore, according to the obtained results, the increase in vegetation cover based on NDVI and the increase in VCI index and comparing it with the temperature of the target area, shows a decrease in the temperature of the earth's surface during these 10 years. As the temperature of the ground surface decreases, it indicates an increase in vegetation cover and the area under rice cultivation. Manuscript profile
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  2 - Investigation expansion and occurrence of red tide in the Persian Gulf and Oman Sea using analysis of MODIS sensor data
  samad Hamzei mohammad sedigh Mortazavi abas ali Aliakbari Bidokht Abolhassan Gheibi
  Cochlodinium polykrikoides red tide occurred in the fall and winter 2008-2009 in the coastal waters of Persian Gulf and Oman Sea that surprised many marine and environmental organizations.This phenomenon with more than thirty tons fisheries mortality More

  Cochlodinium polykrikoides red tide occurred in the fall and winter 2008-2009 in the coastal waters of Persian Gulf and Oman Sea that surprised many marine and environmental organizations.This phenomenon with more than thirty tons fisheries mortality in the Hormozgan province caused to decrease fish consumption by the people. In this research, we received data and images from Aqua and Terra satellites of  ODIS sensor. We used the local algorithms for making Persian Gulf and Oman Sea chlorophyll and temperature images.We compared local algorithm with field measurements and satellite images and observations of real remote sensing data. We corrected spectral coefficients, and ultimately results, was useful expansion rate of harmful algalbloom.Satellite images show increase chlorophyll in areas harmful algal bloom (red tide) was occurred.In the industrial population cities bordering the Strait of Hormuz, algal density is high. The inflow current has important role to Transfusion of red tide to the western regions of the Persian Gulf.Most of the growth of red tide in the north of the Strait can be seen by the satellite is close to 9 months in this area has been steady. Manuscript profile
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  3 - Spatio-temporal Variations of Snow-covered Days in the Northwest of Iran using Remote Sensing Data
  Abbas Kashani Bromand Salahi Amirhossein Halabian Batool Zeinali
  In this research, the spatiotemporal variations of snow-covered days (SCDs) in this region were analyzed using the data of the sixth version of MODIS Terra and MODIS Aqua sensors on a daily basis in the period of 2003-2020. In order to reduce the cloud cover effect, thr More

  In this research, the spatiotemporal variations of snow-covered days (SCDs) in this region were analyzed using the data of the sixth version of MODIS Terra and MODIS Aqua sensors on a daily basis in the period of 2003-2020. In order to reduce the cloud cover effect, three algorithms were applied to the data. For the digital elevation model, the Digital Surface Model (DSM) of the Japan Space Exploration Agency was used. The relation between two snow-cover phenological components (SCAs and SCDs) and the relation between the SCDs and the altitude were investigated. The findings show an increase in SCDs in the months of November, December, and January. Maximum SCDs are observed in January in Sabalan Mountain and then Sahand. The reduction of SCDs in the spring and summer months is also affected by the two factors of latitude and altitude. The absolute maximum of SCDs in this region is observed at 160 days/ year in the mountain of Sabalan. Examining the changes in SCDs in March and April shows a decrease in SCDs in high-altitude classes. At the same time, it shows the increasing pattern of SCDs in November and December at many altitude levels. Analysis of the relation between SCA and SCDs in different months illustrated that SCAs has decreased in regions with more SCDs (heights) due to the reduction of topographic areas. The relation of SCDs and altitude also showed that the minimum of SCDs occurred in all altitude levels (even altitudes above 3500 m with 4 days) in August and the maximum occurred in December with 22 days at the altitude of 3500 m. SCDs decrease with increasing altitude in mountainous areas of 3500 to 4000 m, due to the increase of land slope and instability of SC in steep areas. Manuscript profile
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  4 - Drought monitoring chnages in Droudzan catchment using MODIS images
  marzieh mogholi
  One of the methods of studying drought and its destructive effects is drought monitoring and zoning using meteorological indicators and remote sensing techniques. In order to determine the effect of droughts on vegetation changes, drought intensities were determined usi More

  One of the methods of studying drought and its destructive effects is drought monitoring and zoning using meteorological indicators and remote sensing techniques. In order to determine the effect of droughts on vegetation changes, drought intensities were determined using annual SPI drought indices by rainfall data of meteorological stations. In this research, SPI drought index was investigated in short and one-month periods and the annual period for three stations which according to the results of the calculation of meteorological drought indicators in general in all stations in The 2001, 2003, 2005, 2007, and 2013 droughts have occurred from weak to severe, and also occurred in 2009 and 2014 in the region of Tarsal. Initially, the standard rainfall index (SPI) was calculated for three meteorological stations in Shiraz, Eghlid and Dorogozan during the years 2015 to 2001, and then, based on images taken from MODIS in October, August, September, the normalized vegetation difference index ( NDVI) and then the correlation between meteorological indices and vegetation was taken during the statistical period for dry and wet years. Accurately, the NDVI's statistical results have the highest correlation with drought and climatic variation with the Drooden Station, . Manuscript profile
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  5 - Monitoring of Ashtrankoh glaciers in the catchment area of Gohar Lake in Lorestan and investigating its relationship with vegetation reduction using MODIS images and NDSI index between 1380 and 1395
  mohammad ebrahim afifi vahid sohrabi
  In this study، MODIS satellite images related to the years 2001 to 2015 have been used to prepare a map of the surface under snow cover in Lorestan Province، Ashrankuh Region. The main purpose of the research was to investigate the relationship between natural glaciers More

  In this study، MODIS satellite images related to the years 2001 to 2015 have been used to prepare a map of the surface under snow cover in Lorestan Province، Ashrankuh Region. The main purpose of the research was to investigate the relationship between natural glaciers and vegetation. In this study، it was the NDSI index، which is actually the normalized difference of two spectral bands (visible band and near-infrared band or short-wavelength infrared band)، which is used to extract snow-covered surfaces. k-means algorithm was used for clustering. The results obtained from the changes in the glacial zones have shown a decreasing trend. So that the area covered by glaciers in 2001 was estimated to be around 7500 square meters and in 2015 this amount was estimated to be approximately 5000 square meters. Fluctuation in the changes of each year compared to the next year is very low due to the wideness of the Modis image cell، but in the long term، the decreasing trend of glacier levels is quite clear. Manuscript profile
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  6 - Simulation of snowmelt runoff in Armand basin using SRM model and satellite images
  Matin Sheini Jabari hossein ghorbanizadeh kharazi
  Snow in mountainous areas is one of the main components of the hydrological cycle, however, there are many changes in its temporal and spatial distribution. In this study, the SRM model and remote sensing data were used in order to monitor the time and space of the snow More

  Snow in mountainous areas is one of the main components of the hydrological cycle, however, there are many changes in its temporal and spatial distribution. In this study, the SRM model and remote sensing data were used in order to monitor the time and space of the snow cover level and simulate the runoff caused by snowmelt in Armand Basin. The hydrological data of the basin and the raster data of the MODIS sensor were collected and used for a period of 2 years (water years 2005-06 to 2006-07). After processing MODIS sensor images in ENVI software, the snow cover level was determined. The simulation with the SRM model showed successful and acceptable results. So that the results of the evaluation of the model using two indicators, the Coefficient of determination and the volume difference, showed the high accuracy of the model in estimating the runoff resulting from snowmelt in the Armand Basin. The R2 obtained for Armand Basin is about 0.90. Manuscript profile