Masoud Moradi - Academia.edu (original) (raw)

Papers by Masoud Moradi

Continental Shelf Research, Mar 1, 2022

Journal of Marine Systems, May 1, 2023

Continental Shelf Research, May 1, 2021

Abstract Persian Gulf is a highly turbid and optically complex marginal sea. Satellite remotely s... more Abstract Persian Gulf is a highly turbid and optically complex marginal sea. Satellite remotely sensed chlorophyll-a (Chl-a) products have been widely used in this marine area, despite uncertainties due to complex oceanic and atmospheric optical properties. In this study, accuracy of daily merged multi-sensor Ocean Color Climate Change Initiative (OC–CCI), Copernicus Marine Environmental Monitoring Service (CMEMS) GlobColour, and OC5 single-sensor products of SeaWiFS, MERIS, MODIS, and VIIRS datasets were evaluated using in situ chlorophyll concentrations collected from 2008 to 2018 in the Iranian territorial waters. The results showed that the MAPE, RMSE, bias(δ) and R2 values between in situ and satellite-4 derived Chl-a vary in the range of 131–273%, 0.38–0.69, 0.27–0.43, and 0.27–0.44, respectively. Satellite-derived Chl-a concentrations overestimated the field observations by 131–232% in the northern parts of the middle deeper areas and up to 173–273% in Iranian coastal areas. The OC-CCI and GlobColour merged datasets overestimate the Chl-a concentrations by 19% more than the average of OC5 single-sensor products. Systematic errors were observed in the log-normal distributions of difference between in situ and satellite-derived Chl-a. A bootstrapping-like assessment was performed to eliminate the systematic errors, and to reduce the bias from satellite datasets. The results of statistical adjustment were applied on daily matchup data-pairs and time-series datasets. Furthermore, an inter-comparison was made between merged multi-sensor (OC–CCI, GlobColour CHL2) and OC5 single-sensor (SeaWiFS, MERIS, MODIS, and VIIRS) Chl-a products using 8-day time-series datasets during the years 2000–2020. The results showed that the OC5 single-sensor Chl-a datasets were more consistent with OC-CCI than GlobColour merged CHL2 in the deep and shallow regions of the study area. In contrast, the merged multi-sensor products were more similar to each other than the OC5 single-sensor datasets in the river plume zone. After performing statistical adjustment of time-series datasets, the bias values between OC-CCI, GlobColour CHL2, and OC5 single-sensor datasets decreased by 14–22%, and the single-sensor datasets showed more similarity to OC-CCI datasets.

ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Jan 14, 2023

The Persian Gulf is a peripheral sea that is quite turbid and visually complicated. Because of th... more The Persian Gulf is a peripheral sea that is quite turbid and visually complicated. Because of the complicated oceanic and atmospheric optical features of this maritime area, satellite remotely sensed chlorophyll-a (Chl-a, mg m-3) outputs have been used extensively. In this study, the seasonality and magnitude of Level-3 Chl-a time-series products, and daily Level-2 satellite-derived Chl-a concentrations were assessed using corresponding/concurrent in-situ observations gathered during 2008 to 2018. The results revealed that the field observations overestimated satellite-derived Chl-a by 115% in the deeper areas and up to 161% along the Iranian coastal waters. Comparison of inter-annual Chl-a time-series datasets with corresponding in-situ measurements showed that temporal patterns of the satellite-derived Chl-a values are not consistent with field observations. The monthly average of the satellite Chl-a series shows a different seasonal pattern in every region of the study area, and their magnitude overestimated from 21% to 83% relative to in-situ observations. The absorption coefficients at 488-510 nm are primarily influenced by non-living particles instead of phytoplankton pigments, and no significant correlation are found between in-situ and Chl-a values from OC3/OC4 algorithms. Absorption coefficients spectra of water constituent's shows that the contribution of phytoplankton pigments in particulate absorption coefficients at the bluegreen bands are 48%-59%, and the particulate absorptions of water bodies are under the strong influence of non-living particles (40%-52%). Our results suggest that the red-green band-ratios algorithm centred at 675 nm and 555 nm presents more accurate results than OC3/OC4 over the study area.

40th COSPAR Scientific Assembly, 2014

International Journal of Environmental Science and Technology, 2022

The relationship between the features of the land surface and the atmosphere is well identified b... more The relationship between the features of the land surface and the atmosphere is well identified by its temperature. This parameter is a key tool in investigations of relevant energy equilibrium variations. The purpose of this research is to identify and analyze Land Surface Temperature (LST) variations over Iran using MODIS Aqua data. The modified non-parametric Mann–Kendall test is used for examination of trend significance, and Sen’s slope is used in the calculation of changes rate and direction. The results demonstrated that environmental factors including land cover and elevation have significant effects on LST trend. For inland waters and swamps, positive daytime trends have occurred during the warm months of the year, and negative nighttime trends have occurred during the cold months. The highest frequency of variation per decade corresponds to that between −5 and + 5 degrees Celsius per decade (°C/Decade). The mountainous regions have experienced severe positive daytime variations in the cold months and similar changes in the warm months. The findings also indicate that changes in land cover and use have resulted in LST variations. There have been greater daytime than nighttime such variations, and have occurred at far higher rates for four land covers: the bodies of water, cropland, urban areas, and barren land. The overall results of the research demonstrated that MODIS Aqua LST data are capable of accurately monitoring spatiotemporal variations over Iran.

Continental Shelf Research, 2022

Journal of Great Lakes Research, 2021

Earth Science Informatics, 2020

The present study aimed to examine the capabilities of a low-cost and standard drone (namely, the... more The present study aimed to examine the capabilities of a low-cost and standard drone (namely, the DJI™ Phantom 4 Pro) for mapping of coral reefs in shallow coastal waters. To this end, a coral site in Kish Island, located in the northern Persian Gulf, was selected as the study area, wherein other methods had been previously practiced to generate maps from the corals. The drone flight was operated by the Pix4Dcapture® mobile application, due to its simplicity and high capabilities for performing an automated flight based on user's settings. The flight altitude was set at 50 m, covering the~6 ha (200 × 300 m) area in~5.5 min. Prior to the drone flight, 11 diving buoys were positioned as ground control points (GCPs) on the study area and their coordinates were subsequently measured three times via a handheld GPS. Afterwards, the Agisoft™ Metashape software was utilized to create the orthophoto mosaic from the total number of 121 overlapped taken photos. The spatial resolution of the final orthophoto mosaic was by~2 cm, contributing to the identification of the features with the minimum size of 20 cm. Although the produced mosaic was geo-registered, it was geo-referenced once again based on the above-mentioned GCPs in the ENVI™ 5.3 software to increase planimetric accuracy. Thereafter, the corrected mosaic was digitized by on-screen digitizing in the Autodesk® AutoCAD Map software, so that an identifier (ID) was assigned to each polygon with reference to the types of corals or other substrate features such as the rocks. Consequently, a topological map was generated in the format of the ESRI™ shapefile. The results demonstrated that the proposed technique was capable to differentiate the types of corals (including bleached ones) and other substrate features. In comparison with other alternative methods, the given technique cost lower than field observations and its results were much more accurate compared with those from satellite imagery. The capabilities of the proposed technique may be significantly improved if drones equipped with a multispectral camera were used, but then again, the costs will be increasingly higher.

Continental Shelf Research, 2019

Spatio-temporal variability of Red-Green Chlorophyll-a Index from MODIS data in Chabahar Bay, SE ... more Spatio-temporal variability of Red-Green Chlorophyll-a Index from MODIS data in Chabahar Bay, SE of Iran

Ecotoxicology and Environmental Safety, 2019

Surface sediments, sampled from Iranian coast of the Persian Gulf (n = 134), were analyzed in ord... more Surface sediments, sampled from Iranian coast of the Persian Gulf (n = 134), were analyzed in order to track spatial distribution of PAHs and their related eco-hazards. The levels of PAHs were in the range of 1.98-814 ng g-1 dw and the region was lowly to moderately polluted. The profile of PAHs was mainly composed of 2,3-ring chemicals and suggested a local source of PAHs and relatively fresh inputs. Statistical analysis and molecular fingerprints proposed that the basin receives PAHs from multiple origins including petrogenic and pyrogenic (traffic and auto emission) ones. Spatial distribution of organic matter and fine fraction of the sediments had a horizontally increasing trend in the studied basin. ∑16PAHs showed significant positive correlation with TOC and fine fraction (p < 0.05) and the spatial deposition of ∑16PAHs followed the spatial trends of TOC and fine fraction. Spatial mapping techniques confirmed that Pars Special Economic Energy Zone (PSEEZ) is the hot zone of PAH pollution. A combination of source availability, finer sediments, and great organic matter levels were the main effective factors that highlighted the deposition of PAHs in the PSEEZ. The Nayband Bay, as the Iran's first national marine Park, possibly received PAHs from its adjacent zone, the PSEEZ. On the other hand, low organic matter and sandy nature of the Nayband Bay was not suitable for effective sequestration of PAHs. Thus, the biota of Nayband Park was encountering with relatively severe multiple eco-hazards due to both ecological and economic factors.

Advances in Space Research, 2016

Validation of satellite derived sea surface temperature (SST) is necessary since satellite minus ... more Validation of satellite derived sea surface temperature (SST) is necessary since satellite minus buoy SST (= bias) relies on atmospheric and oceanographic conditions and time periods. This research validates MODIS (Terra and Aqua) satellite daytime SST with buoy SST at the northern Persian Gulf. Sixteen dates during June 2011 to June 2015 were selected for validation. The buoy-satellite matchups were gained within one image pixel (1 km at nadir) and ±6 h in time. For most matchups, time interval was ±3 h. Effects of total column water vapor, aerosol optical depth, wind speed, glint, and satellite zenith angle on bias are then investigated. These parameters are classified based on root mean square (RMS) difference between satellite and buoy SST. Final results represent a near-perfect R 2 (>0.989) for both satellites. The bias was 0.07 ± 0.53°C and À0.06 ± 0.44°C for MODIS-Aqua and-Terra, respectively.

The difference between effective reflectance from sub sea objects and water suspended materials i... more The difference between effective reflectance from sub sea objects and water suspended materials is a function of attenuation coefficient (k) of light intensity in bodies of water. The amount of C-Cmin (here C is digital number) identifies the effective reflectance and it is possible to differentiate the effective reflectance from sub sea objects and water suspended loads using a specific display image of band ratios. In a ratio display image of Landsat TM band pairs, this difference is a function of (1e )/(1 – e). This value for Khark and Kharkoo sub sea objects (Coral reefs and sandy beds) in the Landsat TM image of 1998 is always positive and less than one. Thus a RGB false color of the atmospherically corrected ratio image of effective reflectance (C-Cmin) display image as (C – Cmin)b2/(C – Cmin)b1 ; (C – Cmin)b3/(C – Cmin)b2 ; (C – Cmin)b4/(C – Cmin)b3 : (RGB) shows the best separation of the sub sea objects. The proposed model has been used for detecting coral reefs and sandy b...

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2015

Biophysical properties of water undergo serious variations under red tide (RT) outbreak. During R... more Biophysical properties of water undergo serious variations under red tide (RT) outbreak. During RT conditions, algal blooms spread out in the estuarine, marine and fresh waters due to different triggering factors such as nutrient loading, marine currents, and monsoonal winds. The Persian Gulf (PG) was a talent region subjected to different RTs in recent decade. A massive RT started from the Strait of Hormuz in October 2008 and extended towards the northern parts of the PG covering more than 1200 km of coastlines. The bloom of microorganism <i>C. Polykrikoides</i> was the main specie that generated large fish mortalities, and hampered marine industries, and water desalination appliances. <br><br> Ocean color satellite data have many advantages to monitor and alarm RT occurrences, such as wide and continuous extent, short time of imagery, high accessibility, and appropriate estimation of ocean color parameters. Since 1999, MODerate Resolution Imaging Spectrorad...

Construction and Building Materials, 2006

Abstract The main objective of this research work was to investigate the potential of integration... more Abstract The main objective of this research work was to investigate the potential of integration of geographic information system (GIS), global positioning system (GPS) and computer vision system (CVS) for the purpose of flexible pavement distresses classifications and maintenance priorities. The classification process included distress type, distress severity level and options for repair. A system scheme that integrated the above-mentioned systems was developed. The system utilized the data collected by GPS and a PC-based vision system in a GIS environment. GIS Arcview software was used for the purpose of data display, query, manipulation and analysis. The developed system provided a safer pavement condition data collection technique, flexible data storage, archiving, updating and maintenance priorities updating. Maintenance priorities were assigned based on priority indices values computed by priority index (PI) or available budget criterion. This technique was cost-effective and offered wise-based decision making for different maintenance activities and programs. Using average daily traffic (ADT), distance from maintenance unit ( R ), pavement section area and pavement age, statistical models were developed to forecast pavement distress quantities. It was found that ADT and pavement age variables were the most significant factors in the distresses quantification.

Advances in Space Research, 2022

The capability of Degree Heating Weeks index (DHWs) was examined for prediction of bleaching even... more The capability of Degree Heating Weeks index (DHWs) was examined for prediction of bleaching events in the coral reef communities of the Kish Island located in the north of the Persian Gulf. In doing so, weekly Sea Surface Temperature (SST) values (in 1°×1° spatial resolution) prepared by National Oceanic and Atmospheric Administration (NOAA), coupled with documented bleaching events, such as official reports, published papers, and direct field observations were employed. The SST values of the study area were extracted between 1982 and 2014; subsequently, the corresponding DHWs were determined for the same period. Thereafter, a threshold for DHWs was specified, based on the historical recorded bleaching events. Moreover, for quality assessment of the results, the accuracy of the applied methodology was quantified using Peirce Skill Score (PSS) technique. This technique enabled us to quantify the quality of our hind-casts /forecasts, based on hit rate and alarm rate factors. The resu...

This study examined the advantages of incorporating the new band of Landsat-8 OLI imagery (band 1... more This study examined the advantages of incorporating the new band of Landsat-8 OLI imagery (band 1: Coastal/Aerosol, 435-451 nm) to a model for estimation of Secchi disk depth (SDD) values (as an indicator for transparency) in near-shore coastal waters using multispectral bands. In doing so, Chabahar Bay in the southern part of Iran (north of Gulf of Oman) was selected as the study area. Two approximately four-hour in-situ observations (including 48 and 56 field measured SDD values for each date respectively) were performed in the study area using Secchi disk; this was designed to start about two hours before and end about two hours after the time of satellite overpasses. Thereafter, a model was formed for estimation of SDD values based on the terms including all possible linear and mutual ratio values of Coastal/Aerosol (B1), Blue (B2), Green (B3), and Red bands (B4). In the first step, the correlation between reflectance/ratio reflectance values of these bands and Ln(SDD) values we...

Journal of Great Lakes Research, 2020

The cyanobacterial harmful algal blooms have been observed, over the last decade, in several regi... more The cyanobacterial harmful algal blooms have been observed, over the last decade, in several regions of the southern Caspian Sea, becoming a major threat to human health and aquatic life. The present study aims to develop two models to quantify cyanobacterial concentration in the Caspian Sea using artificial neural networks and multiple band linear regression. The models are based on Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery. Data were collected from the west, center, and east of the southern Caspian Sea between September 2015 and August 2016. The field dataset includes 123 samples in seven different transects and is used to define and evaluate the proposed methods. The Root Mean Square Error (RMSE), unbiased RMSE (URMSE), and correlation coefficient (R) values between Multiple Band Linear Regression Algorithm outputs and field dataset are 1.8 Â 10 À3 mg.m À3 , 22.43%, and 0.73, respectively. For Artificial Neural Network (ANN), the outputs are 1.6 Â 10 À3 mg.m À3 , 18.89%, and 0.81, respectively. The performance of the proposed methods is proven suitable under nearly all conditions of the southern Caspian Sea. However, numerical comparison and visual evaluation of the results show that the ANN method is less sensitive to small changes in the environmental conditions, leading to more stable results. Moreover, the ANN model provides accurate results in most cases, and the accuracy of this results are improved by increasing the training data. This study focused on the development and validation of an optimal algorithm for quantifying temporal and spatial variability phycocyanin concentrations in the Caspian Sea using daily satellite data.

Marine Pollution Bulletin, 2020

Monthly mean satellite derived Chl-a, aerosols, wind, SST, PAR, and turbidity datasets were used ... more Monthly mean satellite derived Chl-a, aerosols, wind, SST, PAR, and turbidity datasets were used to investigate the possible factors regulating phytoplankton variability in the Persian Gulf. The spatial correlation analysis revealed two distinct regions of SST and PAR, and a relatively uniform spatial correlation pattern of the other parameters. The cross correlation between aeolian dusts and Chl-a was significantly positive with 1-3 months offset. The pattern of spatial correlation between Chl-a and SST was positive in the shallow regions without time lag, and was negative with time offset of 3-5 months in deeper regions. The cross correlation between Chl-a and northward winds were positive with time lags of 1-3 months. Vertical mixing under the influence of northward winds in the deeper region, availability of light and nutrients in the shallow regions, and dust fertilizations over the whole area were suggested to be the major controlling factors regulating phytoplankton growth.