HOLOCENE CORAL REEF ON KAUAI, HAWAII: EVIDENCE FOR A SEA-LEVEL HIGHSTAND IN THE CENTRAL PACIFIC

This study compares the noise levels at the cold-water coral Tisler reef, before and after the closure of the border between Norway and Sweden, which occurred as a direct result of the COVID-19 pandemic. The Tisler reef is a marine protected area located under a ferry “highway” that connects Norway and Sweden. Cold-water coral reefs are recognised as being important hotspots of both biodiversity and biomass, they function as breeding and nursing grounds for commercially important fish and are essential in providing ecosystem functions. Whilst studies have shown that fishery, ocean warming, and acidification threaten them, the effects of noise pollution on cold-water coral reefs remains unstudied. To study the severity of noise pollution at the Tisler reef, a long-term acoustic recorder was deployed from 29 January 2020 until 26 May 2020. From 15 March COVID-19 lockdown measures stopped passenger vessel traffic between Norway and Sweden. This study found that the overall noise levels were significantly lower after border closure, due to reduced ferry traffic, wind speeds, and sea level height. When comparing the median hourly noise levels of before vs. after border closure, this study measured a significant reduction in the 63–125 Hz 1/3 octave band noise levels of 8.94 ± 0.88 (MAD) dB during the day (07:00:00–19:59:59) and 1.94 ± 0.11 (MAD) dB during the night (20:00:00–06:59:59). Since there was no ferry traffic during the night, the drop in noise levels at night was likely driven by seasonal changes, i.e., the reduction in wind speed and sea level height when transitioning from winter to spring. Taking into account this seasonal effect, it can be deduced that the COVID-19 border closure reduced the noise levels in the 63–125 Hz 1/3 octave bands at the Tisler reef by 7.0 ± 0.99 (MAD) dB during the day. While the contribution of, and changes in biological, weather-related and geophysical sound sources remain to be assessed in more detail, understanding the extent of anthropogenic noise pollution at the Tisler cold-water coral reef is critical to guide effective management to ensure the long-term health and conservation of its ecosystem functions.

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Hydrodynamic response of a fringing coral reef to a rise in mean sea level

Ocean Dynamics ◽

10.1007/s10236-014-0734-5 ◽

2014 ◽

Vol 64 (7) ◽

pp. 975-987 ◽

Cited By ~ 7

Author(s):

Soheila Taebi ◽

Charitha Pattiaratchi

Keyword(s):

Coral Reef ◽

Sea Level ◽

Mean Sea Level ◽

Hydrodynamic Response

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Loss of coral reef growth capacity to track future increases in sea level

Nature ◽

10.1038/s41586-018-0194-z ◽

2018 ◽

Vol 558 (7710) ◽

pp. 396-400 ◽

Cited By ~ 94

Author(s):

Chris T. Perry ◽

Lorenzo Alvarez-Filip ◽

Nicholas A. J. Graham ◽

Peter J. Mumby ◽

Shaun K. Wilson ◽

...

Keyword(s):

Coral Reef ◽

Sea Level ◽

Reef Growth ◽

Growth Capacity

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A standardized database of Last Interglacial sea-level indicators in southeast Asia: Records from coral reef terraces in a tectonically complex region

10.5194/egusphere-egu21-16151 ◽

2021 ◽

Author(s):

Kathrine Maxwell ◽

Hildegard Westphal ◽

Alessio Rovere

Keyword(s):

Coral Reef ◽

Southeast Asia ◽

Sea Level ◽

Tectonic Setting ◽

Sea Level Change ◽

The Philippines ◽

Sea Level Changes ◽

Last Interglacial ◽

Level Change ◽

Se Asia

<p>The Last Interglacial (LIG), as well as other warmer periods in the Earth&#8217;s geologic history, provides an analogue for predicted warming conditions in the near future. Analysis of sea-level indicators during this period is important in constraining regional drivers of relative sea-level change (RSL) and in modeling future trajectories of sea-level rise. In southeast Asia, several studies have been done to examine LIG sea-level indicators such as coral reef terraces and tidal notches. A synthesis of the state-of-the-art of the LIG RSL indicators in the region, meanwhile, has yet to be done. We reviewed over 50 published works on the LIG RSL indicators in southeast Asia and used the framework of the World Atlas of Last Interglacial Shorelines (WALIS) in building a standardized database of previously published LIG RSL indicators in the region. In total, we identified 38 unique RSL indicators and inserted almost 140 ages in the database. Available data from Indonesia, the Philippines, and East Timor points to variable elevation of sea-level indicators during the LIG highlighting the complex tectonic setting of this region. Variable uplift rates (from as low as 0.02 to as high as 1.1 m/ka) were reported in the study areas echoing various collision and subduction processes influencing these sites. Although several age constraints and elevation measurements have been provided by these studies, more data is still needed to shed more light on the RSL changes in the region. With this effort under the WALIS framework, we hope to identify gaps in the LIG RSL indicators literature in SE Asia and recognize potential areas that can be visited for future work. We also hope that this initiative will help us further understand the different drivers of past sea-level changes in SE Asia and will provide inputs for projections of sea-level change in the future.</p>

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Divergence of seafloor elevation and sea level rise in coral reef ecosystems

Biogeosciences ◽

10.5194/bg-14-1739-2017 ◽

2017 ◽

Vol 14 (6) ◽

pp. 1739-1772 ◽

Cited By ~ 31

Author(s):

Kimberly K. Yates ◽

David G. Zawada ◽

Nathan A. Smiley ◽

Ginger Tiling-Range

Keyword(s):

Coral Reef ◽

Coral Reefs ◽

Sea Level Rise ◽

Sea Level ◽

Anthropogenic Impacts ◽

Regional Scale ◽

Coastal Hazards ◽

Carbonate Production ◽

Coral Reef Ecosystems ◽

Study Sites

Abstract. Coral reefs serve as natural barriers that protect adjacent shorelines from coastal hazards such as storms, waves, and erosion. Projections indicate global degradation of coral reefs due to anthropogenic impacts and climate change will cause a transition to net erosion by mid-century. Here, we provide a comprehensive assessment of the combined effect of all of the processes affecting seafloor accretion and erosion by measuring changes in seafloor elevation and volume for five coral reef ecosystems in the Atlantic, Pacific, and Caribbean over the last several decades. Regional-scale mean elevation and volume losses were observed at all five study sites and in 77 % of the 60 individual habitats that we examined across all study sites. Mean seafloor elevation losses for whole coral reef ecosystems in our study ranged from −0.09 to −0.8 m, corresponding to net volume losses ranging from 3.4  ×  106 to 80.5  ×  106 m3 for all study sites. Erosion of both coral-dominated substrate and non-coral substrate suggests that the current rate of carbonate production is no longer sufficient to support net accretion of coral reefs or adjacent habitats. We show that regional-scale loss of seafloor elevation and volume has accelerated the rate of relative sea level rise in these regions. Current water depths have increased to levels not predicted until near the year 2100, placing these ecosystems and nearby communities at elevated and accelerating risk to coastal hazards. Our results set a new baseline for projecting future impacts to coastal communities resulting from degradation of coral reef systems and associated losses of natural and socioeconomic resources.

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