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The document is a correction notice for an article titled "Estimation of ionospheric Faraday rotation over ocean areas using L-band spaceborne PolSAR data" published in the International Journal of Remote Sensing. The correction addresses errors in the equations presented in the article, specifically related to the use of angle brackets and the omission of certain symbols. The corrected equations are provided in the notice, along with examples of incorrect and correct usage of these symbols in figures and tables. The text emphasizes the importance of using the correct symbols to ensure accurate representation of the data, and the corrections aim to improve the accuracy and clarity of the mathematical representations. [Extracted from the article]

The mineralogical anomaly is the mineralogically diagnostic character that differs from its surrounding spectra in terms of absorption features of a spectrum. On the airless planetary body like our Moon, the characteristics of mineral exposures are mostly affected by the physical process over time because of space weathering. This inevitable fact produces mature exposures that act as a background for mineralogical anomaly detection. In this regard, the present study categorizes the optical maturation trend of a site, and the background characterization is integrated with anomaly detection, which makes it more practical, robust, and efficient. These fundamental ideas have been improvised into our automated mineralogical anomaly detection method that uses a modified density-based spatial clustering of applications with noise (Modified DBSCAN) algorithm to categorize the maturity trend from various scatter plots of spectral property. Subsequently, the Reed-Xiaoli detector analyzes the data points belonging to below 33% of maximum point density on the corresponding scatter plot. Experimentally, the proposed method has been validated with previously reported results of literatures over the varietal lunar sites (crater Theophilus, crater Humboldt, Hansteen Alpha silicic dome, western inner ring of Mare Moscoviense, and crater Von Kármán), which have diverse mineralogy in the region. The reflectance spectra of anomalous points explore the mineralogical diversity of the studied region using Chandrayaaan-1 Moon Mineralogy Mapper ( M 3 ) data. However, it can also operate with any hyperspectral datasets within the spectral range of 400–3000 nm. This flexibility makes our proposition more attractive for an end-user in the field of planetary science. [ABSTRACT FROM AUTHOR]

Most satellites observing sea surface winds have sun-synchronous orbits and provide observation data at the same place two times per a day. A daily mean value estimated from these data suffers from sampling errors because the high-frequency variation including a diurnal change in the wind field cannot be neglected. To overcome this problem, the use of multiple satellites is useful. The purposes of this study were to describe the time variation of the accuracy of daily mean wind data in a third-generation Japanese Ocean Flux Data Sets with Use of Remote Sensing Observations (J-OFURO3) and to investigate its causes by comparison with in situ measurement data from moored buoys. The results reveal that the three statistical measures such as bias, Root Mean Square error and cross correlation coefficient have improved over time. A set of scatter diagrams of the number of satellites versus the statistical measures for each year shows strong correlations. The accuracy of daily mean data provided by J-OFURO3 is concluded to depend on the number of satellites. We also focused on specific time intervals for satellite wind observations, particularly the maximum missing time interval (MMTI) within a day. The results showed that the correlations between the three statistical measures and MMTI were quite high. Because the above-mentioned two causes are not independent, we analysed the combined effect of the two causes together. The results show that the accuracy of daily mean data depends more strongly on MMTI than on the number of observations. By applying these results, it is possible to determine the optimal number of sensors and the optimal observation time to achieve maximum target accuracy. This provides very useful information for the design of satellite observation systems for sea surface wind. [ABSTRACT FROM AUTHOR]

A novel approach involving the use of the contextual information in a scatter plot of Moderate Resolution Imaging Spectrometer (MODIS) derived Land Surface Temperature versus Fraction of Vegetation (LST vs. Fv) has been proposed in this study to obtain pixel-wise values of bulk surface conductance (Gs) for use in the Penman-Monteith (PM) model for latent heat flux (λET) estimation. Using a general expression for Gs derived by assuming a two-source total λET (canopy transpiration plus soil evaporation) approach proposed by previous researchers, minimum and maximum values of Gs for a given region can be inferred from a trapezoidal scatter plot of pixel-wise values of LST and corresponding Fv. Using these as limiting values, Gs values for each pixel can be derived through interpolation and subsequently used with the PM model to estimate λET for each pixel. The proposed methodology was implemented in 5 km × 5 km areas surrounding each of four flux towers located in tropical south-east Asia. Using climate data from the tower and derived Gs values the PM model was used to obtain pixel-wise instantaneous λET values on six selected dates/times at each tower. Excellent comparisons were obtained between tower measured λET and those estimated by the proposed approach for all four flux tower locations (R2 = 0.85–0.96; RMSE = 18.27–33.79 W m–2). Since the LST- Fv trapezoidal method is simple, calibration-free and easy to implement, the proposed methodology has the potential to provide accurate estimates of regional evapotranspiration with minimal data inputs. [ABSTRACT FROM AUTHOR]

Analysis of hybrid polarimetric synthetic aperture radar data has gained importance in the last couple of years with the availability of spaceborne data from Radar Imaging Satellite-1 (RISAT-1). RISAT-1 provides right circular transmit and linear receive data in Fine Resolution Stripmap-1 (FRS-1) mode with a swath of 25 km approximately covering 625 km2areas. But an administrative unit, like a district, in India cannot be covered in single FRS-1 acquisition. In this article, the possibility of acquisition of multi-incidence angle FRS-1 data to cover a larger area in three consecutive days over Khagaria district of Bihar State, India, for maize crop discrimination and mapping was investigated. It was assumed that the difference of 3 days in imaging does not affect the backscatter response from maize crop as there will not be much change in the maize crop characteristics in 3 days. The backscatter response of maize crop, which is in maximum vegetative stage, was studied at three incidence angles (viz. 28°, 42°, and 52°). The analysis was carried out for the discrimination of maize crop at each incidence angle in Raney derived hybrid decomposition parameters viz. Odd bounce, Double bounce, and Volume scattering mechanisms. The result shows that there is a slight difference in the backscatter response from maize crop due to the changes in incidence angle from 28° to 42° and has not shown any significant difference from 42° to 52°. However, the maize crop got well discriminated in the scatter plots of volume and double bounce scattering at both 28° and 42° and with odd and volume scattering combinations at 52°. The classification of the multi-incidence angle data resulted in 47,732 ha of maize cropped area in Khagaria district during rabi (winter season), 2014–15 with the producer’s accuracy of 92.00%. [ABSTRACT FROM PUBLISHER]

For studies of Antarctic climate change, the Advanced Very High Resolution Radiometer (AVHRR) offers a time series spanning more than two decades, with numerous overpasses per day from converging polar orbits, and with radiometrically calibrated thermal infrared channels. However, over the Antarctic Plateau, standard multispectral application of AVHRR data for cloud optical property retrieval with individual pixels is problematic due to poor scene contrasts and measurement uncertainties. We present a method that takes advantage of rapid changes in radiances at well-defined cloud boundaries. We examine a transect of AVHRR-measured radiances in the three thermal infrared channels across a boundary between cloudy and cloud-free parts of the image. Using scatter diagrams, made from the data along this transect, of the brightness temperature differences between channels 3 and 4, and channels 4 and 5, it is possible to fit families of radiative transfer solutions to the data to estimate cloud effective temperature, thermodynamic phase, and effective particle radius. The major approximation with this method is that along such a transect, cloud water path has considerable spatial variability, while effective radius, phase, and cloud temperature have much less variability. To illustrate this method, two AVHRR images centred about the South Pole are analysed. The two images are chosen based on their differing contrasts in brightness temperature between clear and cloud-filled pixels, to demonstrate that our method can work with varying cloud top heights. In one image the data are consistent with radiative transfer simulations using ice cloud. In the other, the data are inconsistent with ice cloud and are well simulated with supercooled liquid water cloud at 241.5 K. This method therefore has potential for climatological investigation of the radiatively important phase transition in the extremely cold and pristine Antarctic environment. [ABSTRACT FROM AUTHOR]

In non-Rayleigh distributed radar images, the number of scatters can be viewed as a Poisson random variable with the mean itself random. It is well known that the image follows the K distribution when the mean is gamma distributed. The recent paper by Delignon and Pieczynski derived three more intensity distributions by taking the mean to follow: the inverse gamma distribution, the beta distribution of the first kind, and the beta distribution of the second kind. In this Technical note, we derive a comprehensive collection of 16 possible forms for the intensity distribution. The corresponding estimation procedures are also derived by the method of moments. We feel that this work will serve as an important reference for statistical modelling of SAR images. [ABSTRACT FROM AUTHOR]

A study has been carried out to analyse the high temporal Ku-band scatterometer data from QuikSCAT with 4.45 km resolution for regional assessment of rice crop phenology. Four-day composite data were used covering the two predominant rice-growing states in India during the monsoon season of 2004. These data were registered with reference to a rice map derived from RADARSAT SAR data of the same season in order to select predominant rice sites. Analysis shows the dual peak backscatter profile of rice crop (at tillering stage and another at maturity). Minima of the backscatter profile were found to coincide with the heading. The derived heading stage using a lognormal curve fitting matched well with the observed dates. The slope of the second peak varied with crop variety, and shows the potential of correlation with the panicle characteristic. [ABSTRACT FROM AUTHOR]