Patterns of pH, temperature and salinity in the Straits of Malacca and the South China Sea with possible relation to riverine run‐offs in the 

region

Anisah Lee AbdullahGeography Section, School of Humanities

Universiti Sains Malaysia

pH and Ocean Acidification

ongoing decrease in the pH and increase in acidity of the Earth's oceans, caused by the uptake of anthropogenic carbon dioxide (CO2) from the atmosphere.

not a peripheral climate issue, it is the other CO2challenge.

riverine run‐offs

The seas in the region

Andaman Sea

Indian Ocean

Straits of Malacca South China Sea

Sulu Sea

Celebes Sea

Pacific Ocean

Types and location of major reefs 

Oceanic reefs and atolls

Clear water fringing reefs

Turbid water reefs

Turbid water reefs

Clear water fringing reefs

Prime Marine Scientific Expedition (EPSP) 2009

ROSES Expedition 2004

pH (South China Sea to Straits of Malacca) 

Fig. 11. Typical pre‐industrial (∼1850), present (1997) and projected (∼2050) (a) NTCO2 and (b) pH vertical profiles of seawater in the SCS.‐normalized total CO2 (NTCO2=TCO2*35/S)

Chen et al. 2006

Fig. 12. Typical pre‐industrial (∼1850), present (1997) and projected (∼2050) (a) Ωc and (b) Ωa vertical profiles of seawater in the SCS.

Chen et al. 2006

Aragonite (South China Sea to Straits of Malacca) 

Seven thousand years of pH and atmospheric CO2

Biodiversity related studies

The Faunal Divide

Andaman Sea

Indian Ocean

Straits of Malacca

South China Sea

Sulu Sea

Celebes Sea

Pacific Ocean

Indian Ocean Fauna Pacific Fauna

The Coral TriangleRed lines connect areas with equal number of coral genus (from Veron, 1995)

The South China Sea

The biodiversity gradient in the South China Sea

Andaman Sea

Indian Ocean

Straits of Malacca

South China Sea

Sulu Sea

Celebes Sea

Pacific Ocean

Water depth at TerumbuSiput

0.5 metre

1 metre

3 metre

10 metre

25 metre

100 metre

2096 metre

The smallest sea cucumber

Human habitation on shallow reefs and coastal towns of Semporna and Tawau

Threats to the coral reefs in the South China Sea

• Coastal development and land reclamation• Coral mining• Destructive fishing practices (trawling, use of cyanide and fish bombing)• Overfishing (especially in coastal waters)• Freshwater run‐off and sedimentation• Eutrophication• Heavy tourism pressure• Sewage and solid waste disposal• Harvesting for the aquarium trade• ‘Dirty’ aquaculture• Introduction of invasive alien species• Chronic oil pollution from maritime traffic

Human induced threats

Threats to the coral reefs in the South China Sea

• Ocean acidification• Rise in sea surface temperature• Sea level rise• Large seismic activity and tsunami waves• Increased frequency of large storms

Other threats

Sea surface temperature

29 March 2010 13 May 2010

31 May 2010 28 June 2010

TelukDatai

Jul 2010 Aug 2010 Sept 2010

Oct 2010Jan 2011

Sequential changes on a coral head following the bleaching event of 2010

Percentage of live coral cover affected by bleaching on the reef of TelukDatai

(July 2010‐Jan 2011)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Jul Aug Sept Oct Jan

2010 2011

NormalBleachingRecoveredDead

Months

Percen

tage cov

er (%

)

Legend:

End of coral bleaching event

Bleached 

TelukDatai

0

20

40

60

80

100

1958

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

Total Suspe

nded

Solid

 (mg/ L)

010203040506070

Percen

tage

 coral

cover (%)

00.20.40.60.81

1.21984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

Sedimen

t rate

(g / cm

2 /d)

Human Population of ASEAN  

Indonesia, 231,369,500

Philippines, 92,226,600

Vietnam, 85,789,573

Thailand, 64,232,760

Myanmar, 50,020,000

Malaysia, 28,306,700

Cambodia, 14,805,000

Lao, 6,320,000 Singapore, 4,987,600 Brunei, 

400,000

0

50

100

150

200

250

300

350

Popu

latio

n (in

 millions)

mid‐2010

mid‐2025

mid‐2050

Source: Population Reference Bureau, 2010

The current and projected population of the ASEAN nations (2010‐2050)

The disputed territories in the South China Sea

Total landing of fish from the Malaysian Seas (2006)

2007 22002008 21002020 2030 2040 2050 2070 2080 2085

World population surpasses 6.6 billion (U.S. Census Bureau)

Global oil production turning point -triggering global recession, food shortages & conflict between nations over dwindling oil supplies(R. Hirsch, Science Applications International Corporation)

Up to 30% of coral reef will likely be lost in Asian coastal waters(IPCC)

Up to 50% of agriculture yields could be reduced due to less rainfall(IPCC)

Arctic Sea could be ice-free in the summer(M. Holland, NCAR)

Biodiversity hotspots are more threatened, a quarter of the world’s plant & animal species could face extinction(J. Malcolm, Conservation Biology)

Electricity production for the world’s existing hydropower stations will decrease(IPCC)

Sea levels could rise at low-lying areas(IPCC)

Risk of dengue fever from climate change is estimated to increase to 3.5 billion people(IPCC)

Disappearance of Arctic ice cap;Ocean pH levels will very likely decrease - ability of shelled marine organisms to form shells or exoskeletons could be impaired(IPCC)

Shortening of Earth’s day due to the shift of the poles towards the Earth’s axis rotation - as a result of ocean expansion(F. Landerer, Max Planck Institute for Meteorology)

Timeline of Climate Change

Increase SST leads to increased of coral bleaching events

Input from riverine run‐offs in the region coupled with the effects of global warming and our increasing release of CO2 into the atmosphere will intensify further the current problems of climate change and its evil twin, the ocean acidification.

Ocean Acidification is real, its happening, its going to affect ocean food chain.

Many questions unanswered but above all “What can we do about it?”

We still lack knowledge but the scientists know enough to be concerned.

There is little doubt that we also have to be the solutions.

In disaster risk, need to consider coastal and marine ecosystem ‐ silent sufferer of the louder disasters .

“It is the individual drop of seawater  that make up  the ocean.”

Thank you

anisah@usm.myzulfigarusm@yahoo.com