West, J. M., and Salm, R. V. 2003. Resistance and resilience to coral
bleaching: implications for coral reef conservation and management. Conservation Biology, 17, 956–967.
Wilkinson, C. R. (ed.), 1998. Status of Coral Reefs of the World:
1998. Townsville: Global Coral Reef Monitoring Network,
Australian Institute of Marine Science.
Wilkinson, C. R. (ed.), 2004. Status of Coral Reefs of the World:
2004. Townsville: Global Coral Reef Monitoring Network,
Australian Institute of Marine Science.
Wilkinson, C. R., and Buddemeier, R. W., 1994. Global climate
change and coral reefs: implications for people and reefs.
Report of the UNEP-IOC-ASPEI-IUCN Global Task Team
on the Implications of Climate Change on Coral Reefs. Gland,
Switzerland: IUCN.
Williams, E. H., and Bunkley-Williams, L., 1990. The world-wide
coral reef bleaching cycle and related sources of coral mortality.
Atoll Research Bulletin, 335, 1–71.
Wilson, S. K., Graham, N. A. J., Pratchett, M. S., Jones, G. P., and
Polunin, N. V. C., 2006. Multiple disturbances and the global
degradation of coral reefs: are reef fishes at risk or resilient?
Global Change Biology, 12, 2220–2234.
Wooldridge, S. A., 2009. Water quality and coral bleaching
thresholds: formalising the linkage for the inshore reefs of the
Great Barrier Reef, Australia. Marine Pollution Bulletin, 58,
745–751.
Wooldridge, S., Done, T., Berkelmans, R., Jones, R., and Marshall, P.,
2005. Precursors for resilience in coral communities in a warming
climate: a belief network approach. Marine Ecology Progress
Series, 295, 157–169.
Cross-references
Climate Change: Impact of Sea Level Rise on Reef Flat Zonation
and Productivity
Climate Change: Increasing Storm Activity
Corals: Environmental Controls on Growth
El Niño, La Niña, and ENSO
Ocean Acidification, Effects on Calcification
Remote Sensing
River Plumes and Coral Reefs
Sea Level Change and Its Effect on Reef Growth
Symbiosis
Temperature Change: Bleaching
Tropical Cyclone/Hurricane
Zooxanthellae
CLIMATE CHANGE: IMPACT OF SEA LEVEL RISE ON
REEF FLAT ZONATION AND PRODUCTIVITY
David Hopley
James Cook University, Townsville, QLD, Australia
Definitions
Climate change: projected changes to atmosphere and
ocean which may affect coral reefs and their biota in
a detrimental way, usually considered over the next 100
years or so.
Sea level rise: one of these projected changes resulting
initially from thermal expansion of the oceans and longer
term melting of glaciers, projected to be 13–68 cm by
2100.
Reef flat: the intertidal part of the coral reef, exposed at
low tide, often sediment covered but with living corals in
pools, for example as micro atolls, or around the lower
edges of the reef flat where exposure is of shorter duration.
Productivity: the production of calcium carbonate
forming the framework and sediments of the reef. Usually
expressed as kilograms per square metre per year (kg m
2
/
year), the figure may be converted into reef accretion rates
by taking into account the density and porosity of the contributing organisms and detrital facies.
Introduction
The impact of sea level rise on coral reef flats was one of
the first considerations raised in relation to climate change
and coral reefs. Most publications in the 1980s considered
the impact to be a beneficial one. This was especially so in
the Indo-Pacific area, where isostatic adjustments had produced a sea level at or above its present position for over
6,000 years. Many reefs are now adjusted to this level with
lagoons infilled, sediments dominating the reef flat and
living corals limited to shallow pools (Figure 1). Such reef
flats are too shallow for at least half the tidal cycle for the
transmission of waves with sufficient energy to entrain
and transport all but the finest sediments.
Many general references on Greenhouse effects emphasized the rejuvenation of reef tops (e.g., Henderson-Sellers
and Blong, 1989) whilst others went as far as suggesting
reefs could be drowned and many ecosystems eliminated
(e.g., Falk and Brownlow, 1989). Some scientific assessments suggested that renewed coral growth would make
reef flats aesthetically more pleasing (e.g., Hopley and
Kinsey, 1988).
Reef flat attributes and sea level rise
Atlantic reefs have experienced a continuous sea level rise
throughout the Holocene (for isostatic reasons) with the
result that their shallowest points are commonly subtidal
and have a living coral cover. They are thus well placed
to accelerate their growth as sea level rises. Indo-Pacific
reefs, however, already at sea level for over 6,000 years,
are very different. Many lagoons have been completely
infilled (see Reef Classification by Hopley (1982)). Rather
than living corals, shingle ridges and cemented platforms
are to be found on the windward margins of many reefs
and mangroves have colonized the sheltered areas behind
them. The result is the typical low wooded island morphology found, for example, on the northern Great Barrier
Reef (GBR). Reef flats are sediment covered often stabilized by binding organisms such as seagrass and macro
algae. Corals, including micro atolls may be confined to
moated parts of the reef flat.
Geomorphologically, these reef flats are inert for much
of the time. As demonstrated by Kench and Brander
(2006), at Warraber Island in Torres Strait (maximum tidal
range ca. 4 m), Lady Elliott Island, in the southern GBR
(1.7 m) and Cocos-Keeling atoll in the Indian Ocean,
(1.2 m), both the high loss of energy of incident waves at
210
CLIMATE CHANGE: IMPACT OF SEA LEVEL RISE ON REEF FLAT ZONATION AND PRODUCTIVITY
bleaching: implications for coral reef conservation and management. Conservation Biology, 17, 956–967.
Wilkinson, C. R. (ed.), 1998. Status of Coral Reefs of the World:
1998. Townsville: Global Coral Reef Monitoring Network,
Australian Institute of Marine Science.
Wilkinson, C. R. (ed.), 2004. Status of Coral Reefs of the World:
2004. Townsville: Global Coral Reef Monitoring Network,
Australian Institute of Marine Science.
Wilkinson, C. R., and Buddemeier, R. W., 1994. Global climate
change and coral reefs: implications for people and reefs.
Report of the UNEP-IOC-ASPEI-IUCN Global Task Team
on the Implications of Climate Change on Coral Reefs. Gland,
Switzerland: IUCN.
Williams, E. H., and Bunkley-Williams, L., 1990. The world-wide
coral reef bleaching cycle and related sources of coral mortality.
Atoll Research Bulletin, 335, 1–71.
Wilson, S. K., Graham, N. A. J., Pratchett, M. S., Jones, G. P., and
Polunin, N. V. C., 2006. Multiple disturbances and the global
degradation of coral reefs: are reef fishes at risk or resilient?
Global Change Biology, 12, 2220–2234.
Wooldridge, S. A., 2009. Water quality and coral bleaching
thresholds: formalising the linkage for the inshore reefs of the
Great Barrier Reef, Australia. Marine Pollution Bulletin, 58,
745–751.
Wooldridge, S., Done, T., Berkelmans, R., Jones, R., and Marshall, P.,
2005. Precursors for resilience in coral communities in a warming
climate: a belief network approach. Marine Ecology Progress
Series, 295, 157–169.
Cross-references
Climate Change: Impact of Sea Level Rise on Reef Flat Zonation
and Productivity
Climate Change: Increasing Storm Activity
Corals: Environmental Controls on Growth
El Niño, La Niña, and ENSO
Ocean Acidification, Effects on Calcification
Remote Sensing
River Plumes and Coral Reefs
Sea Level Change and Its Effect on Reef Growth
Symbiosis
Temperature Change: Bleaching
Tropical Cyclone/Hurricane
Zooxanthellae
CLIMATE CHANGE: IMPACT OF SEA LEVEL RISE ON
REEF FLAT ZONATION AND PRODUCTIVITY
David Hopley
James Cook University, Townsville, QLD, Australia
Definitions
Climate change: projected changes to atmosphere and
ocean which may affect coral reefs and their biota in
a detrimental way, usually considered over the next 100
years or so.
Sea level rise: one of these projected changes resulting
initially from thermal expansion of the oceans and longer
term melting of glaciers, projected to be 13–68 cm by
2100.
Reef flat: the intertidal part of the coral reef, exposed at
low tide, often sediment covered but with living corals in
pools, for example as micro atolls, or around the lower
edges of the reef flat where exposure is of shorter duration.
Productivity: the production of calcium carbonate
forming the framework and sediments of the reef. Usually
expressed as kilograms per square metre per year (kg m
2
/
year), the figure may be converted into reef accretion rates
by taking into account the density and porosity of the contributing organisms and detrital facies.
Introduction
The impact of sea level rise on coral reef flats was one of
the first considerations raised in relation to climate change
and coral reefs. Most publications in the 1980s considered
the impact to be a beneficial one. This was especially so in
the Indo-Pacific area, where isostatic adjustments had produced a sea level at or above its present position for over
6,000 years. Many reefs are now adjusted to this level with
lagoons infilled, sediments dominating the reef flat and
living corals limited to shallow pools (Figure 1). Such reef
flats are too shallow for at least half the tidal cycle for the
transmission of waves with sufficient energy to entrain
and transport all but the finest sediments.
Many general references on Greenhouse effects emphasized the rejuvenation of reef tops (e.g., Henderson-Sellers
and Blong, 1989) whilst others went as far as suggesting
reefs could be drowned and many ecosystems eliminated
(e.g., Falk and Brownlow, 1989). Some scientific assessments suggested that renewed coral growth would make
reef flats aesthetically more pleasing (e.g., Hopley and
Kinsey, 1988).
Reef flat attributes and sea level rise
Atlantic reefs have experienced a continuous sea level rise
throughout the Holocene (for isostatic reasons) with the
result that their shallowest points are commonly subtidal
and have a living coral cover. They are thus well placed
to accelerate their growth as sea level rises. Indo-Pacific
reefs, however, already at sea level for over 6,000 years,
are very different. Many lagoons have been completely
infilled (see Reef Classification by Hopley (1982)). Rather
than living corals, shingle ridges and cemented platforms
are to be found on the windward margins of many reefs
and mangroves have colonized the sheltered areas behind
them. The result is the typical low wooded island morphology found, for example, on the northern Great Barrier
Reef (GBR). Reef flats are sediment covered often stabilized by binding organisms such as seagrass and macro
algae. Corals, including micro atolls may be confined to
moated parts of the reef flat.
Geomorphologically, these reef flats are inert for much
of the time. As demonstrated by Kench and Brander
(2006), at Warraber Island in Torres Strait (maximum tidal
range ca. 4 m), Lady Elliott Island, in the southern GBR
(1.7 m) and Cocos-Keeling atoll in the Indian Ocean,
(1.2 m), both the high loss of energy of incident waves at
210
CLIMATE CHANGE: IMPACT OF SEA LEVEL RISE ON REEF FLAT ZONATION AND PRODUCTIVITY