Turbulence characteristics inferred from time-lagged satellite imagery of surface algae in a shallow tidal sea

Marmorino, G. O.; Smith, Geoffrey B.; Miller, W. David

doi:10.1016/j.csr.2017.08.021

Cited by 6 publications

(5 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Appropriate levels of disturbance in lakes promote nutrient circulation in the water-sedimentalgae system, which increases Microcystis growth rate and prevents the attachment of algae to the sediment, which facilitates blooms. This is consistent with observations that continuous weak winds over large shallow lakes can accelerate the spread of blooms (Marmorino et al 2017). In our study, the growth period of Microcystis was shortened following exposure to high levels of disturbance of 350-400 rpm; under such conditions, the algae rapidly reached a growth peak, and the maximum chl-a concentrations were relatively low.…”

Section: The Influence Of Water Disturbance and Lake Sediment On Microcystis Growthsupporting

confidence: 92%

Analysis of optimal environmental conditions for Microcystis blooms in large, shallow, eutrophic lakes

Cao

You-hai

et al. 2021

All Life

View full text Add to dashboard Cite

Harmful algal blooms caused by cyanobacteria have detrimental impacts on lake ecosystems. Uncovering the factors influencing such blooms could facilitate aquatic ecosystem conservation and early warning activities. The experiment simulated the environmental characteristics of shallow eutrophic Lake Ulansuhai in arid regions of China. The experiments were conducted at various temperatures (6, 10, 19, 25°C) and different nutrient conditions (N: 1 ∼ 6 mg/L, P: 0.05 ∼ 1.00 mg/L) and in the presence of water, algae, and sediment under various disturbance levels (0, 100, 200, 250, 300, 350, 400 rpm). In this study, The optimal Microcystis growth conditions observed in the study were as follows: 19°C ≤ temperature ≤ 25°C; 1.0 mg/L ≤ N ≤ 1.6 mg/L; 0.05 mg/L ≤ P ≤ 0.1 mg/L; 16 ≤ N/P ≤ 20; and lake flow velocity = 10 cm•s −1 (200 rpm). The most suitable pH for the growth of Microcystis is 8.5. Investigating the environmental factors that affect the growth of bloom-forming cyanobacteria could aid the development of early warning systems and guide lake restoration activities under climate warming, N:P imbalance, and varying lake velocity scenarios.

show abstract

Section: The Influence Of Water Disturbance and Lake Sediment On Microcystis Growthsupporting

confidence: 92%

Analysis of optimal environmental conditions for Microcystis blooms in large, shallow, eutrophic lakes

Cao

You-hai

et al. 2021

All Life

View full text Add to dashboard Cite

show abstract

“…Sediment, phytoplankton, and colored dissolved organic matter can all act as passive tracers on short time scales, particularly in coastal and inland waters where disparate water masses interact. Consecutive images of a flow rich with tracer features can be used to infer surface velocities by means of pattern tracking velocimetry, e.g., [7]. However, offshore, smaller gradients in these parameters make them less reliable as tracers for turbulence studies.…”

Section: Visible Light Methodsmentioning

confidence: 99%

Airborne Remote Sensing of the Upper Ocean Turbulence during CASPER-East

et al. 2018

View full text Add to dashboard Cite

This study takes on the challenge of resolving upper ocean surface currents with a suite of airborne remote sensing methodologies, simultaneously imaging the ocean surface in visible, infrared, and microwave bands. A series of flights were conducted over an air-sea interaction supersite established 63 km offshore by a large multi-platform CASPER-East experiment. The supersite was equipped with a range of in situ instruments resolving air-sea interface and underwater properties, of which a bottom-mounted acoustic Doppler current profiler was used extensively in this paper for the purposes of airborne current retrieval validation and interpretation. A series of water-tracing dye releases took place in coordination with aircraft overpasses, enabling dye plume velocimetry over 100 m to 10 km spatial scales. Similar scales were resolved by a Multichannel Synthetic Aperture Radar, which resolved a swath of instantaneous surface velocities (wave and current) with 10 m resolution and 5 cm/s accuracy. Details of the skin temperature variability imprinted by the upper ocean turbulence were revealed in 1-14,000 m range of spatial scales by a mid-wave infrared camera. Combined, these methodologies provide a unique insight into the complex spatial structure of the upper ocean turbulence on a previously under-resolved range of spatial scales from meters to kilometers. However, much attention in this paper is dedicated to quantifying and understanding uncertainties and ambiguities associated with these remote sensing methodologies, especially regarding the smallest resolvable turbulent scales and reference depths of retrieved currents.Keywords: airborne remote sensing; ocean surface currents; upper ocean turbulence BackgroundCapabilities for spatial measurements of ocean surface turbulence are highly desirable for a wide variety of needs ranging from basic studies of upper ocean mixing processes to data assimilation into high-resolution coastal and ocean circulation models. On the global scale, presently available observations of the ocean currents are provided by satellite altimeters, which are limited to mesoscales and resolve only the geostrophic component of the surface current. Much anticipated launches of the

show abstract

“…These complex hydrodynamics promote the resuspension and injection of TSS from the shelf break into the reef matrix, and TSS concentrations in these regions are likely independent of terrestrial sources [91]. The tidal jets have been associated with localised upwelling and nutrient exchange between the Coral Sea and the GBR lagoon [92,93], being an important mechanism of transport and mixing of sediments, nutrients, and phytoplankton production [94]. However, the location and occurrence of tidal jets are scarcely described due to lack of appropriate spatial and temporal resolution observations [95,96].…”

Section: Himawari-8 Total Suspended Solids For the Great Barrier Reefmentioning

confidence: 99%

A Machine Learning Algorithm for Himawari-8 Total Suspended Solids Retrievals in the Great Barrier Reef

et al. 2022

View full text Add to dashboard Cite

Remote sensing of ocean colour has been fundamental to the synoptic-scale monitoring of marine water quality in the Great Barrier Reef (GBR). However, ocean colour sensors onboard low orbit satellites, such as the Sentinel-3 constellation, have insufficient revisit capability to fully resolve diurnal variability in highly dynamic coastal environments. To overcome this limitation, this work presents a physics-based coastal ocean colour algorithm for the Advanced Himawari Imager onboard the Himawari-8 geostationary satellite. Despite being designed for meteorological applications, Himawari-8 offers the opportunity to estimate ocean colour features every 10 min, in four broad visible and near-infrared spectral bands, and at 1 km2 spatial resolution. Coupled ocean–atmosphere radiative transfer simulations of the Himawari-8 bands were carried out for a realistic range of in-water and atmospheric optical properties of the GBR and for a wide range of solar and observation geometries. The simulated data were used to develop an inverse model based on artificial neural network techniques to estimate total suspended solids (TSS) concentrations directly from the Himawari-8 top-of-atmosphere spectral reflectance observations. The algorithm was validated with concurrent in situ data across the coastal GBR and its detection limits were assessed. TSS retrievals presented relative errors up to 75% and absolute errors of 2 mg L−1 within the validation range of 0.14 to 24 mg L−1, with a detection limit of 0.25 mg L−1. We discuss potential applications of Himawari-8 diurnal TSS products for improved monitoring and management of water quality in the GBR.

show abstract

Turbulence characteristics inferred from time-lagged satellite imagery of surface algae in a shallow tidal sea

Cited by 6 publications

References 18 publications

Analysis of optimal environmental conditions for Microcystis blooms in large, shallow, eutrophic lakes

Analysis of optimal environmental conditions for Microcystis blooms in large, shallow, eutrophic lakes

Airborne Remote Sensing of the Upper Ocean Turbulence during CASPER-East

A Machine Learning Algorithm for Himawari-8 Total Suspended Solids Retrievals in the Great Barrier Reef

Contact Info

Product

Resources

About