Impacts of climate change on Impacts of climate change on Australian marine lifeAustralian marine life

Dr Martina Doblin, Senior Research FellowUniversity of Technology Sydney

A presentation prepared for the NSW Department of A presentation prepared for the NSW Department of Education and Training, August 2009 Education and Training, August 2009

What’s so special about the ocean?What’s so special about the ocean?• Life in the ocean has been Life in the ocean has been

evolving 2.7 B years longer than evolving 2.7 B years longer than on landon land

• There are about There are about 40 phyla40 phyla (major (major groups of organisms) in the ocean groups of organisms) in the ocean and at least 15 of them are found and at least 15 of them are found only in the ocean only in the ocean

• BUT, far fewer biological changes BUT, far fewer biological changes identified in the oceans and identified in the oceans and freshwater systems as a result of freshwater systems as a result of climate change climate change (<0.3% of terrestrial systems)(<0.3% of terrestrial systems)

Image source: wikipedia

Earth is 79% ocean!

What’s so special about plankton?What’s so special about plankton?

Source: Dr Lisa Drake

ASPAB 2007, Warrnambool

• Responsible for >40% of global photosynthesisResponsible for >40% of global photosynthesis• Help maintain processes that regulate global climate and cycle essential Help maintain processes that regulate global climate and cycle essential

elements (such as carbon, nitrogen and water) elements (such as carbon, nitrogen and water) • Form the base of the foodwebForm the base of the foodweb

They keep the Earth livable!They keep the Earth livable!

What could happen?

Photo: Miriam GodfreySource: Miriam Godfrey; www. carleton.serc

How is climate change affecting How is climate change affecting the ocean?the ocean?

Source: CSIRO

Ocean circulation is changingOcean circulation is changing

Source: CSIRO

Long term monitoringLong term monitoringalong 110°E

time (month of year)

2 4 6 8 10 12

latit

ud

e (

°S)

20

30

40

50

0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45

along 154°E

time (month of year)

2 4 6 8 10 12

latit

ud

e (

°S)

20

30

40

50

Rottnest IslandRottnest IslandPort HackingPort Hacking

Maria IslandMaria Island

Surface warmingSurface warming

Temperature increase over time, but only in summerTemperature increase over time, but only in summer

surface temperature in January

time (year)

1940 1950 1960 1970 1980 1990 2000 2010

tem

pe

ratu

re (

°C)

10

12

14

16

18

20

22

24

26

Maria IslandPort HackingRottnest Island

surface temperature in July

time (year)

1940 1950 1960 1970 1980 1990 2000 2010

tem

pe

ratu

re (

°C)

10

12

14

16

18

20

22

24

26

Change in seasonal temperature Change in seasonal temperature and timingand timing

1 2 3 4 5 6 7 8 9 10 11 12-100

-80

-60

-40

-20

01

95

3-1

963

1212.51313.51414.51515.51616.51717.51818.51919.52020.52121.52222.52323.52424.525

1 2 3 4 5 6 7 8 9 10 11 12-100

-80

-60

-40

-20

0

1997

-20

07

1953 - 1963

1997 - 2007

What is this equation?What is this equation?

106CO106CO22 + 122H + 122H22O + 16NOO + 16NO33-- + PO + PO44

3-3- + 19H + 19H++

as well as other micronutrients such asas well as other micronutrients such as

silicate silicate (Si) and iron (Fe)(Si) and iron (Fe)

and and phosphatephosphate

nitratenitrate

(CH(CH22O)O)106106

(NH(NH33))1616HH33POPO44 + 138O + 138O22

SUNLIGHTSUNLIGHT

Time (year)

1940 1950 1960 1970 1980 1990 2000 2010

Nitrate : Silicate(molar ratio)

0

1

2

3

4

5

6

0

1

2

3

4

5

6

Nutrient ratios in south-eastern Nutrient ratios in south-eastern Australian waters Australian waters

Thompson et al, in review

Maria Island: all depths, annual mean

Time (year)

1940 1950 1960 1970 1980 1990 2000 2010

Silicate (µM)

0

1

2

3

4

5

6

Nitrate (µM)

0

2

4

6

8

10

12

Si

NO3

Nutrient ratios in south-eastern Nutrient ratios in south-eastern Australian waters Australian waters

Decreased silicate relative to nitrateDecreased silicate relative to nitrate

Thompson et al, in review

Changes in nutrients will lead to Changes in nutrients will lead to changes in biodiversity and functionchanges in biodiversity and function

Source: www.microscopy-uk.org.uk

Changing species compositionChanging species compositionPigment (µg LPigment (µg L-1-1) ) or or Pigment ratio Pigment ratio

(µg:µg)(µg:µg)

1996-97 1996-97 meanmean

1997-98 1997-98 meanmean

2004-05 2004-05 meanmean

% % change change 1996 to 1996 to 20042004

chlorophyll chlorophyll aa 0.660.66 1.361.36 2.002.00 203203

peridininperidinin 0.0110.011 0.260.26 0.670.67 59915991

fucoxanthinfucoxanthin†† 0.1110.111 0.1230.123 0.2630.263 137137

peridinin:chl-aperidinin:chl-a 0.0230.023 0.1480.148 0.2900.290 11611161

fucoxanthin:chlfucoxanthin:chlaa 0.1690.169 0.1080.108 0.1520.152 -11-11

† failed Kolmogorov – Smirnov test for normality & passed Levene median test for equal variance.

Increased prevalence of red tidesIncreased prevalence of red tides

Sources: www.carleton.serc ; www.microscopy-uk.org.uk

How does this all fit together?How does this all fit together?

Less rainLess rain

Decreased SiDecreased Si

SurfaceSurfacewarmingwarming

SummarySummary

• Evidence of:Evidence of: - surface warming - surface warming - extended autumn season - extended autumn season - altered nutrient ratios in south-eastern Australia - altered nutrient ratios in south-eastern Australia

(decreased availability of Si)(decreased availability of Si) - changes in abundance and species composition of - changes in abundance and species composition of phytoplankton phytoplankton

• Functioning of the ocean will change Functioning of the ocean will change with many cascading effectswith many cascading effects

including those on surfers, swimmers, seafood eatersincluding 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, WarrnamboolSource: www.microscopy-uk.org.uk

Potential climate change impactsPotential climate change impactson marine phytoplanktonon marine phytoplankton

• Increased COIncreased CO22 and altered DIC and altered DIC speciationspeciation

• Elevated UVElevated UV

• Higher temperaturesHigher temperatures

• Reduced mixed layer depthReduced mixed layer depth• Changes in ocean currents & Changes in ocean currents &

circulationcirculation

• Increased dissolution of calcifying Increased dissolution of calcifying coccolithophoridscoccolithophorids

• Increased prevalence of species Increased prevalence of species with UV protectionwith UV protection

• Changes in phytoplankton species Changes in phytoplankton species compositioncomposition

• Altered phenology (seasonal Altered phenology (seasonal timing)timing)

• Altered primary productionAltered primary production• Range shiftsRange 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

oceanographiccruises

Limited time series

Before IMOS, no coordinated sampling

IMOS infrastructure

Moorings Gliders Satellite remote sensing Spatial coverage poor good to excellent excellent (cloud cover)Depth resolution good excellent Poor (deep chl-a max)Temporal resolution excellent excellent (intermittent) goodLimitations chemical and biological

sensors limited at presentlimited 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

• 14C 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 CDOMcan introduce significant errors

• Other parameters needed forinterpreting fluorescence

Biooptical dataANFOG

CDOM distribution

Backscatter distribution

• Bloom 2/3 along transect• Some CDOM/particulate interference

at start of transect

Photosynthetic rates

Maria Island: Maria Island: chlorophyll chlorophyll a a 1997 – 2006*1997 – 2006*

• Decline in spring Decline in spring biomass biomass

• Slower growth of Slower growth of spring bloomspring bloom

Time

Aug Oct Dec Feb Apr Jun

chlo

roph

yll a

(µ

g L-1

)

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

average1997199819992000 20012002 2003 20042005 2006

Time

1996 1998 2000 2002 2004 2006 2008

grow

th r

ate

(mo

nth-1

)

0.15

0.20

0.25

0.30

0.35

0.40

0.45

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 researchImplications and future research• Implications include: Implications include:

- temporal mismatch between trophic levels causing a - temporal mismatch between trophic levels causing a change in synchrony of primary, secondary and change in synchrony of primary, secondary and tertiary production tertiary production - changing species composition alters food quality for - changing species composition alters food quality for higher trophic levels, potentially leading to less fish higher trophic levels, potentially leading to less fish production production

• Challenge is to not only describe patterns, but to make Challenge is to not only describe patterns, but to make predictions and test hypotheses about cascading foodweb predictions and test hypotheses about cascading foodweb effectseffects

Potential climate change impactsPotential climate change impactson marine phytoplanktonon marine phytoplankton

• Increased COIncreased CO22 and altered DIC and altered DIC speciationspeciation

• Elevated UVElevated UV

• Higher temperaturesHigher temperatures

• Reduced mixed layer depthReduced mixed layer depth• Changes in ocean currents & Changes in ocean currents &

circulationcirculation

Increased dissolution of calcifying Increased dissolution of calcifying coccolithophoridscoccolithophorids

Increased prevalence of species with Increased prevalence of species with UV protectionUV protection

Changes in phytoplankton species Changes in phytoplankton species compositioncomposition

Altered phenology (seasonal timing)Altered phenology (seasonal timing)

Altered primary productionAltered primary productionChanges in distribution: range shiftsChanges in distribution: range shifts