Search Results (4)

The aerosol optical depth (AOD) was measured along the Tapi River in the Gulf of Khambhat in Surat, Gujarat (India). Satellite data from MODIS relating to the aerosol optical depth (AOD) were collected from the Giovanni site, developed by NASA. In this study, the data from a period of 5 years (January to December 2015 to 2019) are discussed. Variations in the regional meteorological conditions are related to aerosol optical depth characteristics. The annual average AOD variation was observed from the data obtained from January to December 2015–2019. The average annual changes in the aerosol optical depth (AOD) revealed a peak value during the monsoon season, while the seasonal mean aerosol optical depth (AOD) was lowest during the pre-monsoon season, and it was somewhat moderate in the winter season. The post-monsoon season’s variations in the aerosol optical depth (AOD) were comparable to those of the winter and pre-monsoon seasons in 2016. Following this, the values increased and exceeded the maximum for both the Aqua and Terra measurements, owing to changes in the local boundary layer. Full article

Black Carbon (BC) aerosols mass concentration was studied at Surat, Gujarat (India), a coastal region near the Tapi River at the Gulf of Khambhat. Using satellite data for solar extinction due to Black Carbon (BC) mass concentration, data were collected from the Giovanni platform developed by NASA. Results of the data for the 5-year period (January to December 2001–2005) are discussed here. Annual and Seasonal variations of Black Carbon (BC) in relation to changes in the regional meteorological conditions are discussed here. The data collected during January to December 2001–2005 indicated the annual average BC concentration. The mean annual variations of BC aerosols mass concentration saw its maximum in the month of December while minimum was seen in the month of July. The seasonal mean BC mass concentration observed to be at its lowest in monsoon season while its highest was in winter at the study region. Variation of the BC trend observed was higher in the month December and lower in the month of July which is mostly related to the changes in the local boundary layer. Full article

Wind energy is one of the supremely renewable energy sources and has been widely established worldwide. Due to strong seasonal variations in the wind resource, accurate predictions of wind resource assessment and appropriate wind speed distribution models (for any location) are the significant facets for planning and commissioning wind farms. In this work, the wind characteristics and wind potential assessment of onshore, offshore, and nearshore locations of India—particularly Kayathar in Tamilnadu, the Gulf of Khambhat, and Jafrabad in Gujarat—are statistically analyzed with wind distribution methods. Further, the resource assessments are carried out using Weibull, Rayleigh, gamma, Nakagami, generalized extreme value (GEV), lognormal, inverse Gaussian, Rician, Birnbaum–Sandras, and Bimodal–Weibull distribution methods. Additionally, the advent of artificial intelligence and soft computing techniques with the moth flame optimization (MFO) method leads to superior results in solving complex problems and parameter estimations. The data analytics are carried out in the MATLAB platform, with in-house coding developed for MFO parameters estimated through optimization and other wind distribution parameters using the maximum likelihood method. The observed outcomes show that the MFO method performed well on parameter estimation. Correspondingly, wind power generation was shown to peak at the South West Monsoon periods from June to September, with mean wind speeds ranging from 9 to 12 m/s. Furthermore, the wind speed distribution method of mixed Weibull, Nakagami, and Rician methods performed well in calculating potential assessments for the targeted locations. Likewise, the Gulf of Khambhat (offshore) area has steady wind speeds ranging from 7 to 10 m/s with less turbulence intensity and the highest wind power density of 431 watts/m². The proposed optimization method proves its potential for accurate assessment of Indian wind conditions in selected locations. Full article

The circulation of the Gulf of Khambhat (GoK) is studied from a Lagrangian point of view using a 2D numerical model. The model-predicted tide elevation and current speed are in agreement with the observations. Seasonal variations of advection of particles are simulated by releasing 237 particles homogeneously distributed over the Gulf. After one month of simulation, no particles escaped from the GoK except a few from the southern GoK during southwest monsoon (June–September), and the advection of particles was at its maximum in the northern part. Residual eddies are present inside the GoK during the northeast (October–January) and southwest monsoon seasons. Gulf circulation is studied with the combined forcing of tide and wind for different tidal conditions, which had noticeable seasonal difference. The maximum simulated current speeds of 3.4 and 2.8 m/s are noticed during southwest monsoon near to Bhavnagar and Dahej respectively, where the tide elevations are maximum indicating that GoK is a tide-dominated system. A seasonal barrier could be found in the southern Gulf, which not only makes the Gulf circulation distinct from that of the Arabian Sea (AS), but also restricts water-mass exchange between the Gulf and AS during ebb condition. As the Gulf is a dump yard for anthropogenic wastes, the present study puts forward an effort to determine the fate of the waste from a hydrodynamic point of view. Full article