Large-scale coral reef restoration could assist natural recovery in Seychelles, Indian Ocean

Abstract Globally, artificial reefs (ARs) are being increasingly used as a coral reef restoration strategy, and ARs made from conventional substrates (e.g. metal, concrete) have had limited success for coral reef conservation due to structure size and lack of pre-deployment engineering. To curb further deterioration on reefs, technological advances in restoration methods must be quickly tested and applied on a large scale. Here, we present the results of the first IntelliReefs biomimicking “Oceanite” nanotechnology ARs. We compared benthic community composition on three Oceanite ARs 14 months after deployment in Sint Maarten. We also examined fish abundance, diversity, and behaviour on the ARs. The results from this study suggest that Oceanite can enhance local biodiversity, attract coral recruits, provide food and protection for large fish communities, and develop a healthy early coral reef community in 14 months. IntelliReefs' future research will focus on large-scale deployments and further development of site-, species-, and function-specific substrates to optimize AR conservation goals and increase project success. Our Ocean-Shot will deploy durable, bio-enhanced reefs that build resilience to climate change, increase economic benefits, and coastal protection for seaside communities. Oceanite can further be customized for specific stressor mitigation (e.g., pathogens, warming, acidification, reduced water quality, invasive species).

Download Full-text

Subsurface Fluxes Beneath Large-Scale Convective Centers in the Indian Ocean: Coupled Air-Wave-Sea Processes in the Subtropics

10.21236/ada574114 ◽

2012 ◽

Author(s):

James N. Moum

Keyword(s):

Indian Ocean ◽

Large Scale ◽

The Indian Ocean

Download Full-text

Stokes drift through corals

Environmental Fluid Mechanics ◽

10.1007/s10652-021-09811-8 ◽

2021 ◽

Author(s):

Joseph J. Webber ◽

Herbert E. Huppert

Keyword(s):

Coral Reef ◽

Coral Reefs ◽

Porous Layer ◽

Large Scale ◽

Fluid Layer ◽

Ocean Waves ◽

Stokes Drift ◽

Inviscid Fluid ◽

Porous Bed ◽

Vertical Drift

AbstractMotivated by shallow ocean waves propagating over coral reefs, we investigate the drift velocities due to surface wave motion in an effectively inviscid fluid that overlies a saturated porous bed of finite depth. Previous work in this area either neglects the large-scale flow between layers (Phillips in Flow and reactions in permeable rocks, Cambridge University Press, Cambridge, 1991) or only considers the drift above the porous layer (Monismith in Ann Rev Fluid Mech 39:37–55, 2007). Overcoming these limitations, we propose a model where flow is described by a velocity potential above the porous layer and by Darcy’s law in the porous bed, with derived matching conditions at the interface between the two layers. Both a horizontal and a novel vertical drift effect arise from the damping of the porous bed, which requires the use of a complex wavenumber k. This is in contrast to the purely horizontal second-order drift first derived by Stokes (Trans Camb Philos Soc 8:441–455, 1847) when working with solely a pure fluid layer. Our work provides a physical model for coral reefs in shallow seas, where fluid drift both above and within the reef is vitally important for maintaining a healthy reef ecosystem (Koehl et al. In: Proceedings of the 8th International Coral Reef Symposium, vol 2, pp 1087–1092, 1997; Monismith in Ann Rev Fluid Mech 39:37–55, 2007). We compare our model with field measurements by Koehl and Hadfield (J Mar Syst 49:75–88, 2004) and also explain the vertical drift effects as documented by Koehl et al. (Mar Ecol Prog Ser 335:1–18, 2007), who measured the exchange between a coral reef layer and the (relatively shallow) sea above.

Download Full-text

Tropical Cyclone Count Forecasting Using a Dynamical Seasonal Prediction System: Sensitivity to Improved Ocean Initialization

Journal of Climate ◽

10.1175/2010jcli3585.1 ◽

2011 ◽

Vol 24 (12) ◽

pp. 2963-2982 ◽

Cited By ~ 16

Author(s):

Andrea Alessandri ◽

Andrea Borrelli ◽

Silvio Gualdi ◽

Enrico Scoccimarro ◽

Simona Masina

Keyword(s):

Tropical Cyclone ◽

Indian Ocean ◽

Wind Shear ◽

Large Scale ◽

Initial Conditions ◽

North Pacific Ocean ◽

Convective Available Potential Energy ◽

Seasonal Prediction ◽

Boreal Summer ◽

Prediction System

Abstract This study investigates the predictability of tropical cyclone (TC) seasonal count anomalies using the Centro Euro-Mediterraneo per i Cambiamenti Climatici–Istituto Nazionale di Geofisica e Vulcanologia (CMCC-INGV) Seasonal Prediction System (SPS). To this aim, nine-member ensemble forecasts for the period 1992–2001 for two starting dates per year were performed. The skill in reproducing the observed TC counts has been evaluated after the application of a TC location and tracking detection method to the retrospective forecasts. The SPS displays good skill in predicting the observed TC count anomalies, particularly over the tropical Pacific and Atlantic Oceans. The simulated TC activity exhibits realistic geographical distribution and interannual variability, thus indicating that the model is able to reproduce the major basic mechanisms that link the TCs’ occurrence with the large-scale circulation. TC count anomalies prediction has been found to be sensitive to the subsurface assimilation in the ocean for initialization. Comparing the results with control simulations performed without assimilated initial conditions, the results indicate that the assimilation significantly improves the prediction of the TC count anomalies over the eastern North Pacific Ocean (ENP) and northern Indian Ocean (NI) during boreal summer. During the austral counterpart, significant progresses over the area surrounding Australia (AUS) and in terms of the probabilistic quality of the predictions also over the southern Indian Ocean (SI) were evidenced. The analysis shows that the improvement in the prediction of anomalous TC counts follows the enhancement in forecasting daily anomalies in sea surface temperature due to subsurface ocean initialization. Furthermore, the skill changes appear to be in part related to forecast differences in convective available potential energy (CAPE) over the ENP and the North Atlantic Ocean (ATL), in wind shear over the NI, and in both CAPE and wind shear over the SI.

Download Full-text