NSW IMOS and productivity

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Transcript NSW IMOS and productivity

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
Earth is 79% 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)
Image source: wikipedia
What’s so special about plankton?
Source: Dr Lisa Drake
They keep the Earth livable!
• Responsible for >40% of global photosynthesis
• Help maintain processes that regulate global climate and cycle essential
elements (such as carbon, nitrogen and water)
2007,
Warrnambool
• ASPAB
Form
the
base of the foodweb
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
along 110°E
along 154°E
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
20
latitude (°S)
30
latitude (°S)
30
Rottnest Island
20
40
Port Hacking
40
Maria Island
50
50
2
4
6
8
time (month of year)
10
12
2
4
6
8
time (month of year)
10
12
Surface warming
26
26
surface temperature in July
24
24
22
22
temperature (°C)
temperature (°C)
surface temperature in January
20
18
16
14
20
18
16
14
Maria Island
Port Hacking
Rottnest Island
12
10
1940 1950 1960 1970 1980 1990 2000 2010
time (year)
12
10
1940 1950 1960 1970 1980 1990 2000 2010
time (year)
Temperature increase over time, but only in summer
Change in seasonal temperature
and timing
0
1953 - 1963
1953-1963
-20
-40
-60
-80
-100
1
2
3
4
5
6
7
8
9
10
11
12
0
1997-2007
-20
-40
-60
25
24.5
24
23.5
23
22.5
22
21.5
21
20.5
20
19.5
19
18.5
18
17.5
17
16.5
16
15.5
15
14.5
14
13.5
13
12.5
12
-80
1997 - 2007
-100
1
2
3
4
5
6
7
8
9
10
11
12
What is this equation?
nitrate
SUNLIGHT
106CO2 + 122H2O + 16NO3- + PO43- + 19H+
(CH2O)
and
106
(NH3) H3PO4 + 138O2
16
phosphate
as well as other micronutrients such as
silicate (Si) and iron (Fe)
Nutrient ratios in south-eastern
Australian waters
6
6
5
5
4
4
Nitrate : Silicate 3
(molar ratio)
3
2
2
1
1
0
1940
Thompson et al, in review
0
1950
1960
1970
1980
Time (year)
1990
2000
2010
Nutrient ratios in south-eastern
Australian waters
6
12
Maria Island: all depths, annual mean
5
10
4
8
Si
Silicate (µM)
Nitrate (µM)
3
6
2
4
NO3
1
0
1940
Thompson et al, in review
2
0
1950
1960
1970
1980
1990
2000
Time (year)
Decreased silicate relative to nitrate
2010
Changes in nutrients will lead to
changes in biodiversity and function
Source: www.microscopy-uk.org.uk
Changing species composition
Pigment (µg L-1)
or
Pigment ratio
1996-97
mean
1997-98
mean
2004-05
mean
% change
1996 to
2004
chlorophyll a
0.66
1.36
2.00
203
peridinin
0.011
0.26
0.67
5991
fucoxanthin†
0.111
0.123
0.263
137
peridinin:chl-a
0.023
0.148
0.290
1161
fucoxanthin:chla
0.169
0.108
0.152
-11
(µg:µg)
†
failed Kolmogorov – Smirnov test for normality & passed Levene median test for equal variance.
Increased prevalence of red tides
Sources: www.carleton.serc ; www.microscopy-uk.org.uk
How does this all fit together?
Less rain
Surface
warming
Decreased Si
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
• 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
2007, Warrnambool
Source:ASPAB
www.microscopy-uk.org.uk
Potential climate change impacts
on marine phytoplankton
•
•
•
Increased CO2 and altered DIC
speciation
Elevated UV
•
Higher temperatures
•
•
•
•
•
Reduced mixed layer depth
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
Range shifts
The big questions
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.
• 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
Ocean observations
oceanographic
cruises
Limited time series
Before IMOS, no
coordinated sampling
IMOS infrastructure
Spatial coverage
Depth resolution
Temporal resolution
Limitations
Moorings
poor
good
excellent
chemical and biological
sensors limited at present
Gliders
good to excellent
excellent
excellent (intermittent)
limited sensors due to
payload, power and space
issues
Satellite remote sensing
excellent (cloud cover)
Poor (deep chl-a max)
good
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 CDOM
can introduce significant errors
ANFOG
Biooptical data
• Other parameters needed for
interpreting fluorescence
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*
Spring growth rates
Mean monthly chla data
0.35
0.30
0.8
0.25
0.7
-1
chlorophyll a (µg L )
0.20
0.15
1996 1998 2000 2002 2004 2006 2008
0.6
0.4
0.3
0.2
• Decline in spring
biomass
Time
average
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
0.5
-1
0.40
growth rate (month )
0.45
• Slower growth of
spring bloom
0.1
Aug
Oct
Dec
Feb
Apr
Jun
Time
*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)."
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
• Challenge is to not only describe patterns, but to make
predictions and test hypotheses about cascading foodweb
effects
ASPAB 2007, Warrnambool
Potential climate change impacts
on marine phytoplankton
•
•
Increased CO2 and altered DIC
speciation
Elevated UV
•
Higher temperatures
•
•
Reduced mixed layer depth
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