Impacts of climate change on Australian marine life Dr Martina Doblin, Senior Research Fellow University of Technology Sydney A presentation prepared for the NSW Department of Education and Training, August 2009

What’s so special about the ocean? Life in the ocean has been evolving 2.7 B years longer than on land Life in the ocean has been evolving 2.7 B years longer than on land There are about 40 phyla (major groups of organisms) in the ocean and at least 15 of them are found only in the ocean There are about 40 phyla (major groups of organisms) in the ocean and at least 15 of them are found only in the ocean BUT, far fewer biological changes identified in the oceans and freshwater systems as a result of climate change (<0.3% of terrestrial systems) BUT, far fewer biological changes identified in the oceans and freshwater systems as a result of climate change (<0.3% of terrestrial systems) Image source: wikipedia Earth is 79% ocean!

What’s so special about plankton? Source: Dr Lisa Drake

ASPAB 2007, Warrnambool Responsible for >40% of global photosynthesis Responsible for >40% of global photosynthesis Help maintain processes that regulate global climate and cycle essential elements (such as carbon, nitrogen and water) Help maintain processes that regulate global climate and cycle essential elements (such as carbon, nitrogen and water) Form the base of the foodweb Form the base of the foodweb They keep the Earth livable!

What could happen? Photo: Miriam Godfrey Source: Miriam Godfrey; www. carleton.serc

How is climate change affecting the ocean? Source: CSIRO

Ocean circulation is changing Source: CSIRO

Long term monitoring Rottnest Island Port Hacking Maria Island

Surface warming Temperature increase over time, but only in summer

Change in seasonal temperature and timing

What is this equation? 106CO H 2 O + 16NO PO H + as well as other micronutrients such as silicate (Si) and iron (Fe) and phosphate nitrate nitrate (CH 2 O) 106 (NH 3 ) 16 H 3 PO O 2 SUNLIGHT

Nutrient ratios in south-eastern Australian waters Thompson et al, in review

Nutrient ratios in south-eastern Australian waters Decreased silicate relative to nitrate Thompson et al, in review

Changes in nutrients will lead to changes in biodiversity and function Source:

Changing species composition Pigment (µg L -1 ) or Pigment ratio (µg:µg) mean mean mean % change 1996 to 2004 chlorophyll a peridinin fucoxanthin † peridinin:chl-a fucoxanthin:chla † failed Kolmogorov – Smirnov test for normality & passed Levene median test for equal variance.

Increased prevalence of red tides Sources: ;

How does this all fit together? Less rain Decreased Si Surfacewarming

Summary Evidence of: - surface warming - extended autumn season - altered nutrient ratios in south-eastern Australia (decreased availability of Si) - changes in abundance and species composition of phytoplankton Evidence of: - surface warming - extended autumn season - altered nutrient ratios in south-eastern Australia (decreased availability of Si) - changes in abundance and species composition of phytoplankton Functioning of the ocean will change with many cascading effects including those on surfers, swimmers, seafood eaters Functioning of the ocean will change with many cascading effects including those on surfers, swimmers, seafood eaters

Basically, this will impact you!

Thanks -Peter Ralph, University of Technology, Sydney -Tim Ingleton, NSW Dept. of Environment and Climate Change -David Kuo, University of Technology, Sydney research intern -Tim Pritchard, NSW Dept. of Environment and Climate Change -Monitoring teams

ASPAB 2007, Warrnambool Source:

Potential climate change impacts on marine phytoplankton Increased CO 2 and altered DIC speciation Increased CO 2 and altered DIC speciation Elevated UV Elevated UV Higher temperatures Higher temperatures Reduced mixed layer depth Reduced mixed layer depth Changes in ocean currents & circulation Changes in ocean currents & circulation Increased dissolution of calcifying coccolithophorids Increased dissolution of calcifying coccolithophorids Increased prevalence of species with UV protection Increased prevalence of species with UV protection Changes in phytoplankton species composition Changes in phytoplankton species composition Altered phenology (seasonal timing) Altered phenology (seasonal timing) Altered primary production Altered primary production Range shifts Range shifts

The big questions Biological response to oceanographic and climate events Biogeochemical—carbon cycling, including C export Ecological—what are the implications of changes in the quantity and quality of food at the base of the foodweb to higher trophic levels? Ecosystem function and goods & services The NSW IMOS goal is to examine the physical and ecological interactions of the East Australian Current and its eddy field with coastal waters, to assess the synergistic impacts of urbanization and climate change.

Ocean observations oceanographic cruises Limited time series Before IMOS, no coordinated sampling

IMOS infrastructure MooringsGlidersSatellite remote sensing Spatial coveragepoorgood to excellentexcellent (cloud cover) Depth resolutiongoodexcellentPoor (deep chl-a max) Temporal resolutionexcellentexcellent (intermittent)good Limitationschemical and biological sensors limited at present limited sensors due to payload, power and space issues need in situ optical data to tune algorithms in coastal waters

Primary producer observations Chl-a fluorescence Ocean colour CDOM Backscatter PAR Dissolved oxygen Photosynthetic rates 14 C fixation POC/PON HPLC pigments Species composition Continuous Plankton Recorder* Microscope counts Flow cytometer counts Genomics/metabolomics Elemental isotopes Sediment traps

In vivo fluorescence Fluorescence estimates chlorophyll-a without pigment extraction (Lorenzen 1966)—highly sensitive and used over a wide range of spatial and temporal scales to be a universal indicator of phytoplankton biomass Fluorescence yield is variable and dependent on light, cellular nutrient status, temperature, confounded by CDOM  can introduce significant errors

Other parameters needed for interpreting fluorescence Biooptical data ANFOG

CDOM distribution

Backscatter distribution

Bloom 2/3 along transect Some CDOM/particulate interference at start of transect

Photosynthetic rates

Maria Island: chlorophyll a 1997 – 2006* Decline in spring biomass Decline in spring biomass Slower growth of spring bloom Slower growth of spring bloom Mean monthly chla data Spring growth rates *The data were acquired using the GES-DISC Interactive Online Visualization ANd aNalysis Infrastructure (Giovanni) as part of the NASA's Goddard Earth Sciences (GES) Data and Information Services Center (DISC)."

ASPAB 2007, Warrnambool Implications and future research Implications and future research Implications include: - temporal mismatch between trophic levels causing a change in synchrony of primary, secondary and tertiary production - changing species composition alters food quality for higher trophic levels, potentially leading to less fish production Implications include: - temporal mismatch between trophic levels causing a change in synchrony of primary, secondary and tertiary production - changing species composition alters food quality for higher trophic levels, potentially leading to less fish production Challenge is to not only describe patterns, but to make predictions and test hypotheses about cascading foodweb effects Challenge is to not only describe patterns, but to make predictions and test hypotheses about cascading foodweb effects

Potential climate change impacts on marine phytoplankton Increased CO 2 and altered DIC speciation Increased CO 2 and altered DIC speciation Elevated UV Elevated UV Higher temperatures Higher temperatures Reduced mixed layer depth Reduced mixed layer depth Changes in ocean currents & circulation Changes in ocean currents & circulation Increased dissolution of calcifying coccolithophorids Increased prevalence of species with UV protection Changes in phytoplankton species composition Altered phenology (seasonal timing) Altered primary production Changes in distribution: range shifts