huw griffiths understanding global climate change through new breakthroughs in polar research...
TRANSCRIPT
Huw Griffiths
Understanding global climate change through new breakthroughs in polar research
• Changes in sea-ice
• Rising water temperatures
• Ocean acidification
Response of polar marine ecosystems to climate change
Parkinson, 2002
Sea-ice change
declining
growing or stable
Colonies:
50% decrease in krill population
Atkinson et al 2004
1976 - 2003
Over 2-fold decrease / 10 years
Over 2-fold increase / 10 years
© I. Arndt, source: AWI
Bracegirdle, 2008
COPE or ADAPT
MOVE • deeper • further South
Meredith & King 2005
Ocean warming
EXTINCTION
+0.05°C / year
Cheung et al 2009
Changes in species composition - 2050
Sea Ice Zone: January
1991
1993
1998 2000
2001
2002
2003
2004
2005
2006
2007
2008
Stress: 0.05
Southern Ocean Continuous Plankton Recorder
65 mm
0.5 mm
Pre-2000:Pre-2000:large zooplankton (krill)large zooplankton (krill) Post-2000:Post-2000:
small zooplankton (small zooplankton (Oithona)Oithona)
Hosie, pers. com.
Increased CO2 ocean acidification (2100)
calcium carbonate
Orr et al., 2005
© I. Arndt, AWI
Photographs: J. Gutt/W. Dimmler, © AWI/Marum, Univ. Bremen & M. Scheidat, L. Lehnert; results: Gutt et al (submitted to DSR II)
• >8000 known species• 78% of species live on the sea floor• More than half are only known from the Antarctic
Climate Change and Benthic Animals
• Food availability
• Invading predators
• Icebergs
• Heat stress
• Acidification
• Species ranges
Range shifts: Where should we look?
Southern Limits Northern Limits
Barnes et al., 2009
Summary
• Sea-ice changes directly affect the Antarctic marine life
• Warming is expected to change species compositions: invasions, migrations
and extinctions
• Acidification a possible problem for pelagic and benthic species
• Shifts in species ranges will be the first indication of major changes affecting
the seafloor life
For more information about climate change in the Antarctic:“Antarctic Climate Change and the Environment (ACCE)”
www.scar.org
Acknowledgements
I would like to thank all those who helped in the making of
this talk.
Especially Julian Gutt, Graham Hosie, all those involved
in the SCAR climate change report and my colleagues at
the British Antarctic Survey.