Space station image captures a red tide ciliate bloom at high spectral and spatial resolution

Mesodinium rubrum is a globally distributed nontoxic ciliate that is known to produce intense red-colored blooms using enslaved chloroplasts from its algal prey. Although frequent enough to have been observed by Darwin, blooms of M. rubrum are notoriously difficult to quantify because M. rubrum can aggregate into massive clouds of rusty-red water in a very short time due to its high growth rates and rapid swimming behavior and can disaggregate just as quickly by vertical or horizontal dispersion. A September 2012 hyperspectral image from the Hyperspectral Imager for the Coastal Ocean sensor aboard the International Space Station captured a dense red tide of M. rubrum (106 cells per liter) in surface waters of western Long Island Sound. Genetic data confirmed the identity of the chloroplast as a cryptophyte that was actively photosynthesizing. Microscopy indicated extremely high abundance of its yellow fluorescing signature pigment phycoerythrin. Spectral absorption and fluorescence features were related to ancillary photosynthetic pigments unique to this organism that cannot be observed with traditional satellites. Cell abundance was estimated at a resolution of 100 m using an algorithm based on the distinctive yellow fluorescence of phycoerythrin. Future development of hyperspectral satellites will allow for better enumeration of bloom-forming coastal plankton, the associated physical mechanisms, and contributions to marine productivity.

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Morphological Band Registration of Multispectral Cameras for Water Quality Analysis with Unmanned Aerial Vehicle

Remote Sensing ◽

10.3390/rs12122024 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2024 ◽

Cited By ~ 1

Author(s):

Wonkook Kim ◽

Sunghun Jung ◽

Yongseon Moon ◽

Stephen C. Mangum

Keyword(s):

Unmanned Aerial Vehicle ◽

Red Tide ◽

Spatial Scales ◽

Quality Analysis ◽

Geometric Transformation ◽

Concentration Estimation ◽

Individual Bands ◽

Aerial Vehicle ◽

Short Time ◽

The Impact

Multispectral imagery contains abundant spectral information on terrestrial and oceanic targets, and retrieval of the geophysical variables of the targets is possible when the radiometric integrity of the data is secured. Multispectral cameras typically require the registration of individual band images because their lens locations for individual bands are often displaced from each other, thereby generating images of different viewing angles. Although this type of displacement can be corrected through a geometric transformation of the image coordinates, a mismatch or misregistration between the bands still remains, owing to the image acquisition timing that differs by bands. Even a short time difference is critical for the image quality of fast-moving targets, such as water surfaces, and this type of deformation cannot be compensated for with a geometric transformation between the bands. This study proposes a novel morphological band registration technique, based on the quantile matching method, for which the correspondence between the pixels of different bands is not sought by their geometric relationship, but by the radiometric distribution constructed in the vicinity of the pixel. In this study, a Micasense Rededge-M camera was operated on an unmanned aerial vehicle and multispectral images of coastal areas were acquired at various altitudes to examine the performance of the proposed method for different spatial scales. To assess the impact of the correction on a geophysical variable, the performance of the proposed method was evaluated for the chlorophyll-a concentration estimation. The results showed that the proposed method successfully removed the noisy spatial pattern caused by misregistration while maintaining the original spatial resolution for both homogeneous scenes and an episodic scene with a red tide outbreak.

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The red-tide ciliate Mesodinium rubrum in Korean coastal waters

Harmful Algae ◽

10.1016/j.hal.2013.10.006 ◽

2013 ◽

Vol 30 ◽

pp. S53-S61 ◽

Cited By ~ 20

Author(s):

Wonho Yih ◽

Hyung Seop Kim ◽

Geumog Myung ◽

Jong Woo Park ◽

Yeong Du Yoo ◽

...

Keyword(s):

Coastal Waters ◽

Red Tide ◽

Mesodinium Rubrum

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Plasma processing and chemistry

Pure and Applied Chemistry ◽

10.1351/pac200274030369 ◽

2002 ◽

Vol 74 (3) ◽

pp. 369-380 ◽

Cited By ~ 18

Author(s):

Daniel C. Schram

Keyword(s):

Surface Science ◽

Materials Science ◽

Plasma Deposition ◽

High Growth ◽

Radical Mechanism ◽

Short Time ◽

Further Development ◽

C2h Radical ◽

Very High ◽

Monolayer Coverage

Plasma deposition and plasma conversion can be characterized by five steps: production by ionization, transfer of chemistry to precursors, transport of radicals to the surface, surface interactions with deposition, recirculation and generation of new monomers. For very fast deposition, large flows of radicals are needed and a regime is reached, in which monolayer coverage is reached in a very short time. Such large flows of radicals can be obtained by ion-induced interactions, as the C2H radical from acetylene for a-C:H deposition, or by H atom abstraction as the SiH3 radical from SiH4 for a-Si:H deposition. These radicals with intermediate sticking coefficient are advantageous as they are mobile and have a finite dwelling time at the surface. By such a pure radical mechanism, good layers can be formed with very high growth rates, if large radical fluxes can be reached. This regime of high fluence is also interesting for conversion, of which ammonia formation from hydrogen and nitrogen atoms is given as an example. These new approaches offer new possibilities for further development of the field in close connection with surface science, catalysis, and materials science.

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Cloud Photogrammetry from Space

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

10.5194/isprsarchives-xl-7-w3-247-2015 ◽

2015 ◽

Vol XL-7/W3 ◽

pp. 247-254 ◽

Cited By ~ 1

Author(s):

K. Zakšek ◽

A. Gerst ◽

J. von der Lieth ◽

G. Ganci ◽

M. Hort

Keyword(s):

Brightness Temperature ◽

Spatial Resolution ◽

Space Station ◽

Atmospheric Temperature ◽

Multiple Cameras ◽

International Space ◽

Earth Observations ◽

Atmospheric Temperature Profile ◽

Short Time ◽

Short Time Evolution

The most commonly used method for satellite cloud top height (CTH) compares brightness temperature of the cloud with the atmospheric temperature profile. Because of the uncertainties of this method, we propose a photogrammetric approach. As clouds can move with high velocities, even instruments with multiple cameras are not appropriate for accurate CTH estimation. Here we present two solutions. The first is based on the parallax between data retrieved from geostationary (SEVIRI, HRV band; 1000 m spatial resolution) and polar orbiting satellites (MODIS, band 1; 250 m spatial resolution). The procedure works well if the data from both satellites are retrieved nearly simultaneously. However, MODIS does not retrieve the data at exactly the same time as SEVIRI. To compensate for advection in the atmosphere we use two sequential SEVIRI images (one before and one after the MODIS retrieval) and interpolate the cloud position from SEVIRI data to the time of MODIS retrieval. CTH is then estimated by intersection of corresponding lines-of-view from MODIS and interpolated SEVIRI data. The second method is based on NASA program Crew Earth observations from the International Space Station (ISS). The ISS has a lower orbit than most operational satellites, resulting in a shorter minimal time between two images, which is needed to produce a suitable parallax. In addition, images made by the ISS crew are taken by a full frame sensor and not a push broom scanner that most operational satellites use. Such data make it possible to observe also short time evolution of clouds.

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Dynamics of the extremely elongated cloud on Mars Arsia Mons volcano

10.5194/egusphere-egu2020-433 ◽

2020 ◽

Author(s):

Jorge Hernandez Bernal ◽

Agustín Sánchez-Lavega ◽

Teresa del Río-Gaztelurrutia ◽

Ricardo Hueso ◽

Iñaki Ordóñez-Etxeberria ◽

...

Keyword(s):

Martian Atmosphere ◽

Dust Storms ◽

Western Slope ◽

Global State ◽

Local Surface ◽

Daily Cycle ◽

Solar Time ◽

Physical Mechanisms ◽

Short Time ◽

Local Cloud

<p>Starting in September 2018, a daily repeating extremely elongated cloud was observed extending from the Mars Arsia Mons volcano. We study this Arsia Mons Elongated Cloud (AMEC) using images from VMC, HRSC, and OMEGA on board Mars Express, IUVS on MAVEN, and MARCI on MRO. We study the daily cycle of this cloud, showing how the morphology and other parameters of the cloud evolved with local time. The cloud expands every morning from the western slope of the volcano, at a westward velocity of around 150m/s, and an altitude of around 30-40km over the local surface. Starting around 2.5 hours after sunrise (8.2 Local True Solar Time, LTST), the formation of the cloud resumes, and the existing cloud keeps moving westward, so it detaches from the volcano, until it evaporates in the following hours. At this time, the cloud has expanded to a length of around 1500km. Short time later, a new local cloud appears on the western slope of the volcano, starting around 9.5 LTST, and grows during the morning.</p><p>This daily cycle repeated regularly for at least 90 sols in 2018, around Southern Solstice (Ls 240-300) in Martian Year (MY) 34. According with these and previous &#160;MEx/VMC observations, this elongated cloud is a seasonal phenomenon occurring around Southern Solstice every Martian Year. We study the interannual variability of this cloud, the influence of the Global Dust Storms in 2018 on the cloud&#8217;s properties (S&#225;nchez-Lavega et al., Geophys. Res. Lett. 46, 2019), and its validity as a proxy for the global state of the Martian atmosphere (S&#225;nchez-Lavega et al., J. Geophys. Res., 123, 3020, 2018). We discuss the physical mechanisms behind the formation of this peculiar cloud in Mars.</p>

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A Red Tide Caused by the Marine Ciliate Mesodinium rubrum in Passamaquoddy Bay, Including Pigment and Ultrastructure Studies of the Endosymbiont

Journal of the Fisheries Research Board of Canada ◽

10.1139/f77-066 ◽

1977 ◽

Vol 34 (3) ◽

pp. 413-416 ◽

Cited By ~ 10

Author(s):

Alan W. White ◽

Robert G. Sheath ◽

Johan A. Hellebust

Keyword(s):

British Columbia ◽

Endoplasmic Reticulum ◽

New Brunswick ◽

Red Tide ◽

Marine Ciliate ◽

Mesodinium Rubrum ◽

Endosymbiotic Alga ◽

Passamaquoddy Bay

A red tide caused by Mesodinium rubrum was observed in Passamaquoddy Bay, New Brunswick, during August 1975. The chlorophyll and phycoerythrin composition and ultrastructure of the endosymbiotic alga are similar to those described for M. rubrum from Ecuador and British Columbia, including the fact that the endosymbionts do not appear to contain a nucleus. Special ultrastructural features are a complete endoplasmic reticulum surrounding symbiont chloroplast, pyrenoid, and starch bodies, ciliate trichocysts with electron-dense and electron-translucent regions, and curious symbiont mitochondria–ciliate macronuclei associations.

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Notes on the Mass Occurrence of the Ciliate Mesodinium rubrum (non-toxic red tide) in Malacca River, Malaysia

Jurnal Biologi Indonesia ◽

10.47349/jbi/13012017/167 ◽

2017 ◽

Vol 13 (1) ◽

pp. 167-169

Author(s):

Suriyanti Su Nyun Pau ◽

Dzulhelmi Muhammad Nasir ◽

Gires Usup

Keyword(s):

Red Tide ◽

Mesodinium Rubrum ◽

Mass Occurrence

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Models for the Prediction of Transients in Closed Regenerative Gas Turbine Cycles With Centrifugal Impellers

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.1806450 ◽

2005 ◽

Vol 127 (3) ◽

pp. 505-513 ◽

Cited By ~ 3

Author(s):

Theodosios Korakianitis ◽

N. E. Vlachopoulos ◽

D. Zou

Keyword(s):

Gas Turbine ◽

Transient Response ◽

Transient Flow ◽

Space Station ◽

Turbine Engine ◽

Physical Mechanisms ◽

Disturbance Propagation ◽

Solar Powered ◽

Energy And Momentum ◽

Component Models

This paper presents transient-flow component models for the prediction of the transient response of gas turbine cycles. The application is to predict the transient response of a small solar-powered regenerative gas-turbine engine with centrifugal impellers. The component sizes are similar to those under consideration for the solar-powered Space Station, but the models can easily be generalized for other applications with axial or mixed-flow turbomachinery. New component models for the prediction of the propagation of arbitrary transients in centrifugal impellers are developed. These are coupled with component models for the heat exchangers, receiver and radiator. The models are based on transient applications of the principles of conservation of mass, energy, and momentum. System transients driven by sinusoidal and double-step inputs in receiver salt temperature are presented and discussed. The new turbomachinery models and their coupling to the heat-exchanger models simulates disturbance-propagation in the components both upstream and downstream from the point of generation. This permits the study of the physical mechanisms of generation and propagation of higher-frequency contents in the response of the cycle.

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