Global Imaging Data Research Articles

SSBD: an ecosystem for enhanced sharing and reuse of bioimaging data.

SSBD (https://ssbd.riken.jp) is a platform for the sharing and reuse of bioimaging data. As part of efforts to build a bioimaging data ecosystem, SSBD has recently been updated to a two-tiered data resource comprising SSBD:repository, a public repository for the sharing of all types of bioimaging data reported in journals, and SSBD:database, an added-value database for the sharing of curated, highly reusable, metadata-rich data. This update addresses the conflicting demands of rapid data publication and sharing of richly annotated data, thereby promoting bioimaging data sharing and reuse. With this update, SSBD is now positioned as a core repository and database within the foundingGIDE, an international consortium working to establish a global image data ecosystem. Harmonizing metadata between data resources enables cross-searching and data exchange with data resources from other countries and regions.

Analysis of Surface Temperature in Buru District Using Cloud Computing on Google Earth Engine

Monitoring land surface temperature in Buru Regency using Google Earth Engine cloud computing-based geospatial technology can help in understanding global climate and weather change, as well as provide important information for scientists, governments, and non-governmental organizations in making decisions related to climate change mitigation and natural disaster management. This research aims to analyze land surface temperature in Buru Regency using MODIS satellite image data based on the cloud computing google earth engine. This research uses Moderate Resolution Imaging Spectroradiometer (MODIS) Terra Land Surface Temperature and Emissivity 8-Day Global image data analyzed on Google Earth Engine. The results show that the lowest land surface temperature value in Buru Regency is 12, 7438ᵒ C, and the highest value is 31, 9582ᵒ C. The area that has a land surface temperature (LST) in the very high class has an area of 96,604.46 ha or 19.90%, the LST area in the high class is 139,606.47 ha or 28.76%, the LST area in the medium class is 140,853.38 ha or 29.02%, the LST area in the low class is 79,896.56 ha or 16.46% and the LST area in the very low class is 28,458.57 ha or 5.86%. The land surface temperature analysis in Buru Regency can provide important information for the local government in making policies and planning for sustainable regional development.

Analysis of Floating Macroalgae Distribution around Japan Using Global Change Observation Mission-Climate/Second-Generation Global Imager Data

Floating macroalgae information is required to manage coastal environments and fishery resources effectively. In situ observations and analyses can result in under-sampling, thereby challenging the comprehension of the floating macroalgae abundance and spatiotemporal alterations. This study reports the spatiotemporal variation of floating macroalgae distribution around Japan from 2018 to 2021 using Global Change Observation Mission-Climate/second-generation Global Imager data. We employed the floating algae index (FAI) scaled from local ocean FAI to minimize the effect of spatial variation in ocean color. Fractional macroalgae coverage in a pixel was determined using a linear unmixing algorithm with lower and upper thresholds. The lower threshold was determined using the cumulative frequency of the scaled FAI, and the upper threshold was modified based on the more precise Sentinel-2 data. The results revealed that monthly macroalgae coverage varies spatially and seasonally, peaking in the spring and summer in the southwestern area. The macroalgae distribution particularly expanded from the East China Sea to west Japan during spring. In 2018–2021, the total biomass of the offshore floating macroalgae was estimated to be 8880–133,790, 8460–141,900, 3910–70,380, and 4620–61,870 tons. The findings of this study validated the empirical knowledge about specific locations and can serve as a reference to analyze temporal and spatial variations in future studies.

Mars Reconnaissance Orbiter's Mars Color Imager (MARCI): A New Workflow for Processing Its Image Data

AbstractThe Mars Reconnaissance Orbiter's (MRO's) Mars Color Imager (MARCI) has returned approximately daily, approximately global image data of Mars since late 2006, in up to seven different colors, from ultraviolet through near‐infrared. To‐date, that is over 5,300 Mars days of data, nearly eight full Mars Years, or more than 15 Earth years. The data are taken at up to nearly 500 m per pixel, and the nearly circular orbit of MRO and its consistent early afternoon imaging provide an unprecedented baseline of data with which to study Mars' atmosphere and surface processes. Unfortunately, processing MARCI data is difficult, fraught with exploding file sizes, issues that require work‐arounds in free software, and other problems that make this a severely under‐utilized data set. This article discusses a workflow to process MARCI data to their fullest, including suggestions on how to work around issues unique to MARCI and how the data work with the current version of the free software ISIS (Integrated Software for Imagers and Spectrometers). Discussion of some trades that can be made to dramatically speed data processing are also described. Examples of processed MARCI images, mosaics, and color composites are shown, demonstrating the abilities of this workflow on global, regional, and local areas at the full, 96 pixels per degree scale afforded by MARCI.

A Theoretical Study of the Tomographic Reconstruction of Magnetosheath X‐Ray Emissions

AbstractWe present an initial assessment of using tomography on single‐spacecraft images to reconstruct 3D X‐ray emissions from the Earth's magnetosheath. 3D structures in the Earth's magnetosphere have been studied using superposed epoch techniques with single‐point single‐spacecraft observations. They have yielded great insights, but some studies are observation starved, particularly for infrequent solar wind conditions. Global imaging data have provided more insight about these structures, but are 2D projections of 3D structures. We explore the use of tomographic reconstruction techniques to understand what can be extracted from global images from a single spacecraft. The Solar wind Magnetosphere Ionosphere Link Explorer mission, due to launch in 2024 on a 3‐year mission, will carry a soft X‐ray imager which will capture emissions from portions of the magnetosheath and upstream solar wind. We already demonstrated that the 3D shape of the magnetopause and the bow shock can be extracted from such images with suitable assumptions. The next step is to examine whether full 3D reconstructions of the emissions are possible. We explore the limited range of viewing angles, which affect the accuracy of the reconstructions and introduce artifacts in some cases, and the low count‐rates in the images which introduce noise in the reconstructions which must be filtered out. Despite these limitations we show that it is possible to reconstruct some aspects of the magnetosheath global morphology using single‐spacecraft soft X‐ray imaging.

Disk-resolved photometric modeling and properties of asteroid (101955) Bennu

OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) is a NASA mission to return a sample of asteroid (101955) Bennu. Photometric modeling of Bennu's surface is a key element of both sample site characterization and our broader scientific understanding of the asteroid. Bennu's heterogeneous surface presents substantial variation in reflectance and produces a scattered dataset that poses a challenge to photometric modeling. We show that the resolution of the shape model with which we calculate photometric angles strongly affects the accuracy of the analysis, as well as the efficacy of subsequent photometric corrections. We use global imaging data to fit empirical photometric models of the surface. These models represent the average behavior of Bennu's surface and can be used beyond this work to photometrically correct panchromatic and color basemaps of Bennu and perform albedo analyses of individual features on Bennu's surface. Bennu's global photometry reveals a moderate opposition effect and detectable phase reddening, both of which suggest a macroscopically rough surface, which is confirmed by centimeter-scale images of the asteroid.

GLOBAL BUNDLE ADJUSTMENT WITH VARIABLE ORIENTATION POINT DISTANCE FOR PRECISE MARS EXPRESS ORBIT RECONSTRUCTION

Abstract. The photogrammetric bundle adjustment of line scanner image data requires a precise description of the time-dependent image orientation. For this task exterior orientation parameters of discrete points are used to model position and viewing direction of a camera trajectory via polynomials. This paper investigates the influence of the distance between these orientation points on the quality of trajectory modeling. A new method adapts the distance along the trajectory to the available image information. Compared to a constant distance as used previously, a better reconstruction of the exterior orientation is possible, especially when image quality changes within a strip. In our research we use image strips of the High Resolution Stereo Camera (HRSC), taken to map the Martian surface. Several experiments on the global image data set have been carried out to investigate how the bundle adjustment improves the image orientation, if the new method is employed. For evaluation the forward intersection errors of 3D points derived from HRSC images, as well as their remaining height differences to the MOLA DTM are used. In 13.5 % (515 of 3,828) of the image strips, taken during this ongoing mission over the last 12 years, high frequency image distortions were found. Bundle adjustment with a constant orientation point distance was able to reconstruct the orbit in 239 (46.4 %) cases. A variable orientation point distance increased this number to 507 (98.6 %).

GLOBAL BUNDLE ADJUSTMENT WITH VARIABLE ORIENTATION POINT DISTANCE FOR PRECISE MARS EXPRESS ORBIT RECONSTRUCTION

The photogrammetric bundle adjustment of line scanner image data requires a precise description of the time-dependent image orientation. For this task exterior orientation parameters of discrete points are used to model position and viewing direction of a camera trajectory via polynomials. This paper investigates the influence of the distance between these orientation points on the quality of trajectory modeling. A new method adapts the distance along the trajectory to the available image information. Compared to a constant distance as used previously, a better reconstruction of the exterior orientation is possible, especially when image quality changes within a strip. <br><br> In our research we use image strips of the High Resolution Stereo Camera (HRSC), taken to map the Martian surface. Several experiments on the global image data set have been carried out to investigate how the bundle adjustment improves the image orientation, if the new method is employed. For evaluation the forward intersection errors of 3D points derived from HRSC images, as well as their remaining height differences to the MOLA DTM are used. <br><br> In 13.5 % (515 of 3,828) of the image strips, taken during this ongoing mission over the last 12 years, high frequency image distortions were found. Bundle adjustment with a constant orientation point distance was able to reconstruct the orbit in 239 (46.4 %) cases. A variable orientation point distance increased this number to 507 (98.6 %).

Post-launch analysis, calibration, and validation of CCD line of sight for a space-borne push-broom electro-optical sensor using a global image data set

This article describes a technique which estimates line-of-sight (LOS) parameters of each CCD array in a high-resolution electro-optical sensor on board a satellite using statistical information which is extracted automatically from a large number of real images acquired after launch. First, the focal length of panchromatic (PAN) CCD arrays is estimated by using thousands of ground control points (GCPs) converted to raw image space. Second, a model is introduced for deriving LOS parameters for multispectral (MS) CCD arrays in one focal plane assembly (FPA) such as the focal lengths and the first/last detector cell positions from automatically matched band-to-band (B2B) tie-points. Finally, the LOS parameters of all arrays in one FPA are updated using automatically matched tie-points in the overlap zone (OZ) in order to represent the geometrical relationship between the CCD arrays with the same spectral band in two FPAs. The proposed technique was applied to the calibration of a ground segment image processor for a currently operating high-resolution imaging satellite during its initial commissioning phase. This article describes the accuracy and robustness of the LOS parameters estimated by the proposed technique by using more than one hundred images covering full geographical locations and off-nadir tilt angle ranges.

Estimation of the helium ion density distribution in the plasmasphere based on a single IMAGE/EUV image

AbstractWe have developed a technique by which to estimate the spatial distribution of plasmaspheric helium ions based on extreme ultraviolet (EUV) data obtained from the IMAGE satellite. The estimation is performed using a linear inversion method based on the Bayesian approach. The global imaging data from the IMAGE satellite enable us to estimate a global two‐dimensional distribution of the helium ions in the plasmasphere. We applied this technique to a synthetic EUV image generated from a numerical model. This technique was confirmed to successfully reproduce the helium ion density that generated the synthetic EUV data. We also demonstrate how the proposed technique works for real data using two real EUV images.

Photometric correction of Mercury's global color mosaic

During the third flyby of Mercury by the MESSENGER spacecraft, a dedicated disk-integrated photometric sequence was acquired with the wide-angle multispectral camera to observe Mercury's global photometric behavior in 11 spectral filters over as broad a range of phase angle as possible within the geometric constraints of the flyby. Extraction of disk-integrated measurements from images acquired during this sequence required careful accounting for scattered light and residual background effects. The photometric model fit to these measurements is shown to fit observed radiances at phase angles below 110°, possibly except where both solar incidence and emission angles are high (>70°). The complexity of the scattered light at wavelengths greater than 828 nm contributes to a less accurate photometric correction at these wavelengths. The model is used to correct the global imaging data set acquired at a variety of geometries to a common geometry of incidence angle=30°, emission angle=0°, and phase angle=30°, yielding a relatively seamless mosaic. The results here will be used to correct image mosaics of Mercury acquired in orbit.

Evolution of auroral asymmetries in the conjugate hemispheres during two substorms

[1] Five hours of simultaneous global imaging data from the conjugate hemispheres are used to examine the dynamics of the auroral substorm. Earlier studies have demonstrated that substorm onset locations in the two hemispheres are systematically displaced due to the orientation of the interplanetary magnetic field. In this paper we present, for the first time, how the asymmetric auroras induced by the IMF orientation at substorm onset disappears during the expansion phase. We suggest that this is the large scale manifestation of auroral arcs as being the sites of magnetic stress release. Magnetic stress on field lines with asymmetric footpoints can lead to a net hemispherical difference in parallel electric field strength which implies that the auroras move with different speeds in the two hemispheres to release the magnetic stress. The relative velocity can be derived from the potential between the hemispheres. During expansion phase the twisted magnetic fields are rectified, bringing the closed magnetic field lines back to the configuration defined by the Earth's interior.

Estimating photosynthetically available radiation at the ocean surface from ADEOS-II global imager data

A simple, yet efficient and fairly accurate algorithm is presented to estimate photosynthetically available radiation (PAR) at the ocean surface from Global Imager (GLI) data. The algorithm utilizes plane-parallel radiation-transfer theory and separates the effects of the clear atmosphere and clouds, i.e., the planetary atmosphere is modeled as a clear atmosphere positioned above a cloud layer. PAR is computed as the difference between the incident 400–700 nm solar flux at the top of the atmosphere (known) and the solar flux reflected back to space by the atmosphere and surface (derived from GLI radiance), taking atmospheric absorption into account. Knowledge of pixel composition is not required, eliminating the need for cloud screening and arbitrary assumptions about sub-pixel cloudiness. For each GLI pixel, clear or cloudy, a daily PAR estimate is obtained. Diurnal changes in cloudiness are taken into account statistically, using a regional diurnal albedo climatology based on 5 years of Earth Radiation Budget Satellite (ERBS) data. The algorithm results are verified against other satellite estimates of PAR, the National Centers for Environmental Prediction (NCEP) reanalysis product, and in-situ measurements from fixed buoys. Agreement is generally good between GLI and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) estimates, with root-mean-squared (rms) differences of 7.9 (22%), 4.6 (13%), and 2.7 (8%) Einstein/m2/day on daily, weekly, and monthly time scales, and a bias of only 0.8–0.9 (about 2%) Einstein/m2/day. The rms differences between GLI and Visible and Infrared Spin Scan Radiometer (VISSR) estimates and between GLI and NCEP estimates are smaller and larger, respectively, on monthly time scales, i.e., 3.0 (7%) and 5.0 (14%) Einstein/m2/day, and biases are 1.1 (2%) and −0.2 (−1%) Einstein/m2/day. The comparison with buoy data also shows good agreement, with rms inaccuracies of 10.2 (23%), 6.3 (14%), and 4.5 (10%) Einstein/m2/day on daily, weekly, and monthly time scales, and slightly higher GLI values by about 1.0 (2%) Einstein/m2/day. The good statistical performance makes the algorithm suitable for large-scale studies of aquatic photosynthesis.

Atmospheric correction scheme for GLI with absorptive aerosol correction

The present study proposes an atmospheric correction scheme for Advanced Earth Observation Satellite II (ADEOS-II)/Global Imager (GLI) ocean color retrieval that corrects for the atmospheric absorptive aerosol effect. Radiative transfer simulations were conducted assuming a non-absorptive model aerosol with a soot-type aerosol at various mixture ratios. The results indicate that while the spectral dependency of aerosol reflectance does not change in the longer (>550 nm) wavelength region, the reflectance at shorter wavelengths is highly variable and depends on the mixture ratio. The influence of aerosol absorption was also investigated using GLI data from ocean areas adjacent to Japan in the presence of absorptive Siberian fire smoke aerosol in the spring of 2003. The spectral curvature of the aerosol was estimated from the data obtained. An empirical, iterative scheme that detects and evaluates the influence of absorptive aerosols was developed by comparing 380 nm GLI-observed aerosol reflectance with predicted reflectances derived using an in-water optical model. To evaluate the performance of this scheme, satellite-derived normalized water-leaving radiances were compared with those measured from a ferry servicing Nagasaki and Fukue. The results of data acquired on March 20, 2003, indicate that this absorption correction scheme improved root mean square estimation error for normalized water-leaving radiance by approximately 40% in the 380, 400, and 412 nm bands. This atmospheric correction algorithm was used as a part of the second version of the GLI standard ocean color data process system at Japan Aerospace Exploration Agency (JAXA).

Relative merits of the 1.6 and 3.75 μm channels of the AVHRR/3 for cloud detection

A study was performed to investigate the potential impacts of the cloud-masking capability of the advanced very high resolution radiometer (AVHRR) on board the National Oceanic and Atmospheric Administration (NOAA) polar orbiting satellites because of the addition of the 1.6 µm channel (ch3a) and the removal of the 3.75 µm channel (ch3b) during daylight operation. Both channels are measured by the AVHRR, but only one is available in the data stream. Because the AVHRR presents the longest time series of global imager data, this change could impact a critical source of climate data. Specifically, changes in its cloud-masking capability may introduce a discontinuity in its derived clear-sky data records. To study the relative cloud-detection capabilities of the AVHRR with ch3a or ch3b, data from the moderate resolution imaging spectroradiometer (MODIS) on the National Aeronautics and Space Administration (NASA) TERRA mission was used because it offers ch3a, ch3b, and the other AVHRR channels simultaneously. The MODIS data analysis indicated that ch3b offered more capability in separating cloud from snow. Cloud-masking results with ch3a and ch3b were comparable with respect to the separation of cloud from aerosol and the detection of cloud over a desert scene. Although these results are preliminary and based on a limited analysis, they do indicate that the switch from ch3b to ch3a may have significant impacts on the cloud-detection capability of the AVHRR.

The Sinusoidal Projection: A New Importance in Relation to Global Image Data

The reprojection of image data causes the loss or duplication of original pixel values. This research investigated the feasibility of using the sinusoidal projection for global image database construction. Specifically, reprojection accuracies were tested with geographic latitude and longitude coordinates, and the Hammer-Aitoff, Eckert IV, Mollweide, and sinusoidal projections. Reprojections between these five global projections and the Universal Transverse Mercator (UTM) projection and referencing system were performed using fifty-four sample datasets. A statistical analysis of categorical accuracy, a measure describing the omission of pixel values during reprojection, was conducted. Geographic coordinates and the sinusoidal projection both showed very high accuracy rates (100.0 percent and 99.5 percent respectively) when sample datasets were reprojected from UTM. The geographic coordinates, however, showed very low accuracy (65.3 percent) when sample datasets were reprojected to the UTM projection, while the sinusoidal projection showed the highest accuracy (98.4 percent). The results strongly suggest that the sinusoidal projection is very accurate and efficient for building global image databases.

Lunar iron and titanium abundance algorithms based on final processing of Clementine ultraviolet‐visible images

The Clementine mission to the Moon returned global imaging data collected by the ultraviolet visible (UVVIS) camera. This data set is now in a final state of calibration, and a five‐band multispectral digital image model (DIM) of the lunar surface will soon be available to the science community. We have used observations of the lunar sample‐return sites and stations extracted from the final DIM in conjunction with compositional information for returned lunar soils to revise our previously published algorithms for the spectral determination of the FeO and TiO2 content of the lunar surface. The algorithms successfully normalize the effects of space weathering so that composition may be determined without regard to a surface's state of maturity. These algorithms permit anyone with access to the standard archived DIM to construct high spatial resolution maps of FeO and TiO2 abundance. Such maps will be of great utility in a variety of lunar geologic studies.

Plasma and magnetic flux transport associated with auroral breakups

Auroral breakups are the first visible sign of a substorm expansion onset. Keying the plasma sheet behavior to onset times of auroral breakups may help to identify the substorm onset process. With this goal in mind, we have identified a list of auroral breakups based on global imaging data from the Ultraviolet Imager of the POLAR spacecraft for two favorable viewing periods and have examined the simultaneous plasma measurements in the tail from GEOTAIL. Synoptic patterns of plasma transport and magnetic field changes in the tail surrounding the times of auroral breakups are constructed. The results indicate that the plasma sheet activities associated with auroral breakups are transient and spatially localized. These findings are consistent with the scenario in which expansion phase activities are dominated by localized, transient disturbances as portrayed by the substorm synthesis model.

Regional and global stratigraphy of Venus: a preliminary assessment and implications for the geological history of Venus

Photogeologic analysis of Magellan images for 36 widespread sites and several larger areas permits the definition and characterization of a sequence of mappable stratigraphic units and tectonic structures deforming them. Seven rock-stratigraphic units, three related time-stratigraphic units (Systems), and three geologic time subdivisions (Periods) are proposed to describe the vast majority of the areas under study. The first widespread geologic unit preserved on Venus is the highly deformed tessera terrain formed during the Fortunian Period, apparently the result of an event that destroyed the morphology of preexisting terrain and any superposed craters. Global image data reveal no evidence for extensive terrain dating from the pre-Fortunian time, comprising the first 80–90% of the history of Venus, although rocks dating from this period are almost certainly contained within the tessera. Immediately following the Fortunian an extensive period of plains volcanism began, the Guineverian Period, during which the majority of Venus was volcanically resurfaced. During the Guineverian early widespread plains of the Sigrun Group were deformed by extensive and closely-spaced graben systems. Continued widespread plains emplacement occurred and units of the Lavinia Group were deformed, some into extensive ridge belts, recording a change from distributed extensional deformation to often-focused compressional deformation. Plains of the Rusalka Group are the most widespread currently exposed, and are characterized by extensive development of wrinkle ridges of compressional origin. These Guineverian Period plains must have been emplaced and deformed over a relatively short period of time (probably less than about a hundred million years) because the vast majority of impact craters are superposed on the plains, and the crater retention age of this surface is of the order of 300–500 Ma. This extensive plains volcanism then gave way to materials of the Atla Group, local volcanic edifices and flow units with sources associated with coronae and rifts that were emplaced in the late Guineverian and Aurelian Periods. The Aurelian Period, defined by impact craters with dark parabolas, is interpreted to extend from the present back to about 30–50 Ma ago. During this period extensive rifting occurred in several areas of Venus and volcanism has continued at a reduced level relative to the earlier parts of the Guineverian period. Our observations favor a model in which the observed part of the geologic history of Venus (which is the last 20% or less) started with catastrophic tectonic deformation and volcanic resurfacing, followed by the period of declining surface activity of endogenic origin which lasts until now. The lack of surface units representing the first 80–90% of the history of Venus is remarkable from the standpoint of its present low level of activity. This contrast, together with the emerging geologic history of the last 10% of the lifetime of Venus, suggest that catastrophic and/or episodic global processes may have characterized Venus in its earlier history. This factor may also provide an insight into earliest Earth history.