environmental change that is unconnected with climate

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Transcript environmental change that is unconnected with climate

The Eawag Workshop on Climate and Water
Preliminary summary of results and implications for
bundling relevant future research at Eawag
Special thanks to the working group leaders:
Jürg
Beer
(Global
issues)
Flavio
Anselmetti
(Palæolimnology)
Bas
Ibelings
(Aquatic
ecosystems)
Ole
Seehausen
(Fish)
Olaf
Cirpka
(Groundwater)
Urs von Gunten (Drinking water and water technology)
Andreas
Klinke
(Societal
issues)
and to all the rest of you who participated!
Brief
history
of
the
topic
Preliminary summary of main results of workshop
Some
suggestions
for
common
research
Plenary
discussion
Summary
Climate and zooplankton, UK
George & Harris (1985): Nature 316, 536-539.
"Year-to-year
fluctuations in the
biomass of crustacean
zooplankton in Lake
Windermere are strongly
correlated with
variations in water
temperature, but poorly
correlated with the
abundance of the
dominant planktivorous
fish.”
Air and water temperatures in
the Lake District are strongly
related to the sea-surface
temperature to the west of the
UK, implying a large-scale
climatic influence.
"This represents the first
conclusive evidence of
climatologically induced
variability in a freshwater
planktonic system."
George & Taylor (1995): Nature 378, 139.
Zooplankton biomass related to position of
the north wall of the Gulf Stream
Climate-related regional coherence
Magnuson, Benson & Kratz (1990): Freshw. Biol. 23, 145-159.
Lakes in N. Wisconsin connected by:
(i) common climatic forcing
(ii) groundwater flow
"Coherence between lakes was greater for limnological
variables directly influenced by climatic factors than for
variables either indirectly affected by climate of
complexly influenced by other types of factors"
“Lake 239” (ELA, Ontario), 1969-1988
Schindler, Beaty, Fee, Cruikshank, DeBruyn, Findlay, Linsey, Shearer, Stainton & Turner (1990): Science 250, 967-970.
EU projects (with Eawag involvement)
Coordinated by Glen George
• EU FP4 project "REFLECT" (1998–2000)
• EU FP5 project "CLIME" (2001-2003)
Coordinated by Rick Battarbee
• EU FP3 project "MOLAR" (1996-1999)
• EU FP5 project "EMERGE" (2000-2003)
• EU FP6 project "Euro-limpacs" (20042009)
Relevant international research networks
(initiated by John Magnuson and coworkers)
• LTER (Long Term Ecological Research)
• LIAG (Lake Ice Analysis Group)
• GLEON (Global Lake Ecological Observatory Network)
Global aspects
What contribution can we make to solving global-scale climate-change problems?
1)
Work is already ongoing on global-scale problems relevant to climate change
For example:
- Greenhouse gases (CH4)
- Solar forcing (Be in Greenland ice)
- Adapt approach to existing global-scale problems to allow for the expected
impacts of climate change? E.g. SODIS; Arsenic in groundwater.
2)
The predicted main changes are a shift in mean values and, more
importantly, an increase in variability
- Reconstruction of past climate change and “intelligent monitoring” of present
climate change at carefully selected sites
3)
“Space-for-time substitution” and “Space-for-space substitution”
Climate change results in a horizontal shift of climate zones over hundreds to
thousands of kilometres. Translated to altitude, the same shifts correspond merely
to hundreds of metres.
The selection of 3-4 ecosystems at different altitudes in the Alps would offer the
opportunity to study large-scale climate shifts within Switzerland (analogues)
4)
Water availability and water quality in mountain regions
Many aspects apparently specific to the Alps are actually also relevant to other
mountain regions: transfer of know-how.
Palæolimnology
Using the past as the key to the future
1) Lake sediments enable us to quantify natural climate variability, thus allowing
predicted
changes
to
be
put
into
historical
perspective
Warmer time windows in the Holocene can be used as analogues for future climate
scenarios
(How
will
the
future
be?
Look
into
the
past!)
2) Climate change as a driver of ecosystem change in the past
Lake sediments archive various proxies that document past physical, chemical and
biological changes in the ecosystem in response to various past climates. This allows the
impact of past climate change on these ecosystems to be assessed.
3) A gap to be filled: past and future changes in precipitation
The natural range in precipitation (extreme events/floods and background values) have so
far not been quantified, although these are crucial in future climate scenarios and for the
assessment of natural hazards. Investigation of critical proxies for precipitation.
4)
Again:
“space-for-space
substitution”
Climate change has a stronger impact at high latitudes than at low latitudes. The impact of
past climates on a vertical gradient of environments (rather than a horizontal one) could
be investigated in the Alpine area.
Aquatic ecosystems
From monitoring to understanding, predicting and managing
the effects of climate change on aquatic ecosystems
1)
Monitoring
- Set up and maintain ‘clever’ monitoring systems that will capture the true dynamics of
changing
aquatic
ecosystems,
e.g.
community
dynamics.
(GLEON...)
2)
Understanding
- Which changes in water quality and in aquatic ecosystems can be demonstrably attributed
to
climate
change?
- What determines the resilience of the response of ecosystems to change?
What
is
the
capacity
of
ecosystems
to
adapt?
3)
Predicting
Use a deepened understanding of the effects of climate change on aquatic ecosystems to
improve,
calibrate
and
validate
ecosystem
models.
4)
Managing
Incorporate the adaptive responses of society into the study of ecosystem change.
Fish
Background, objectives and current limitations
Broad agreement that:
1. Fish communities are changing rapidly. Patterns are poorly documented, drivers are
poorly understood. There are strong indications that climate change is an important
driver.
2. Switzerland is a hotspot of diversity and endemism of cold-adapted fish species.
Several have already become extinct
3. Switzerland is geographically uniquely positioned for research on climate change
impacts on fish, and we think it is highly relevant to Eawag‘s mission
Objective of a research program “climate and fish”:
Understanding and predicting responses of fish assemblages to climate change
Current limitations:
1. Lack of quantitative data on fish communities in Swiss lakes and rivers
2. Limited understanding of relative importance of and interaction between abiotic and
biotic climate-driven stressors
3. Limited understanding of potential responses of fish species to climate change
Fish
An integrated programme “climate and fish” would include:
1. Literature analyses and formal meta-analyses, relying on data mostly from
other regions of the world, but also Swiss grey literature. These would
address a number of key issues that would guide the data collection
strategy.
2. Generation of a time zero+ baseline data set on fish community
composition and genetic diversity in the major Swiss lakes and rivers.
3. Establishment of long-term data series in a network of waters covering
elevational gradients and the biogeographical regions.
4. Hypothesis-driven experimental work to quantify the potential of
evolutionary response to climate change in key species.
5. Theoretical and quantitative ecological and genetic modelling to integrate
these parallel approaches.
Groundwater
The impact of climate and environmental change on aquifers
1) Direct impacts of climate change on groundwater bodies are probably less
important
than
indirect
impacts
Changes
in
land
use,
agricultural
practice,
legislation
- Factor environmental change into integrated water resources management
2) In CH: Impact of droughts is more important than the impact of warming
Needed:
Vulnerability
study
of
Swiss
aquifers
3) Key project in CH: Follow the process chain from environmental changes to
groundwater
quality
Needed:
Well
studied
aquifer
system
+
calibrated
model
- Hypothesis: Change in hydrology  change in groundwater hydrogeochemistry 
threat
to
current
practice
of
groundwater
use
4) Eawag‘s contribution to climate and groundwater in semi-arid regions:
Geogenic
pollution
in
a
changing
climate
Drinking water and water technology issues
1)
Changes
in
→
Effect
Upgrading
river
of
discharge
on
(proportion
of
groundwater
wastewater
wastewater)
quality?
treatment?
2) Changes in agricultural practices (irrigation, changes in application of
fertiliser,
manure,
pesticides)
→
Effects
on
groundwater
quality
and
quantity
3)
Changes
in
temperature
and
mixing
regimes
of
lakes
→ Effect on phytoplankton and cyanobacterial population, taste and odour,
cyanotoxins.
Adequate
treatment?
4) Institutional/organisational problems in coping with the effects of climate
change on water supplies
Societal issues
Governance and research approaches
1)
Governance
in
Switzerland
- Resilience and flexibility of current water management systems
- Adequacy of current regulations and management practices (including monitoring) to
tackle
the
relationship
between
water
resources
and
climate
- Integration of stakeholders to understand and deal with emerging problems better
Integrated
water
resource
management
2)
-
3)
Governance
in
developing
High
vulnerability
of
Development
of
technological
Capacity
building
Interdisciplinary
and
and
transition
countries
urban
water
systems
and
organisational
solutions
and
empowerment
transdisciplinary
4)
Involvement
of
Eawag
(e.g., WMO, IPCC, FAO, UNESCO, UNEP...)
with
research
international
approaches
bodies
Some common and important issues
1) Reconstructing the past and monitoring the present - “intelligent monitoring”
(referring to human intelligence) and “clever monitoring” (referring to the capabilities of the
monitoring
system)
2) Understanding processes - because understanding is a prerequisite to robust
modelling
3) Broadness of approach - interdisciplinary, international, cooperative, involving
stakeholders
and
external
partners
4)
Distinguish
between:
(i) environmental change that is the direct result of climate change;
(ii) environmental change that is the indirect result of climate change; and
(iii) environmental change that is unconnected with climate change.
Some common and important issues
4)
Distinguish
between:
(i) environmental change that is the direct result of climate change;
(ii) environmental change that is the indirect result of climate change; and
(iii) environmental change that is unconnected with climate change.
Direct:
- Interface between climate and aquatic physics (e.g., shifts in the heat balance of lakes and
rivers; shifts in the phenology of ice and of mixing). But there are some direct biological and
chemical effects (e.g. impact of changes in cloud cover on photosynthesis; impact of
changing
air
temperature
on
pH
in
catchments).
Indirect:
- Interface between aquatic physics and other aquatic disciplines - climate is not directly
involved. E.g. Impacts of higher water temperatures on phytoplankton (mesocosm
experiments)
or
on
fish
habitats.
Unconnected:
- Impacts of urbanisation, new technologies, global and local economics, population shifts,
legislation changes, agricultural practices etc. etc. etc..... Essentially unpredictable in the
long term.
Some common and important issues
4)
Distinguish
between:
(i) environmental change that is the direct result of climate change;
(ii) environmental change that is the indirect result of climate change; and
(iii) environmental change that is unconnected with climate change.
So why should we bother studying the impacts of climate change on water resources when
the impacts of other types of environmental change (e.g. social change) that are much less
quantifiable
are
likely
to
be
greater?
What
we
can
predict,
we
should.
- It is important to establish a “framework of thought” well in advance of the strongest
impacts - i.e., to be intellectually prepared. The models (even intellectual, conceptual
models) have to be in place in good time so they can be employed, refined and made more
quantifiable closer to the time of impact, when the social changes are easier to predict than
now.
Water resources as an endangered species
Contamination
Ing, Sandec,
U-Chem, U-Mik
Climate
Surf, W+T, Eco
Climate
Siam
Wave 21
Agriculture
U-Chem
Contamination
WRQ
W+T,
WRQ
EcoGWP
Record
Eco,
Surf,
W+T
Climate
W+T
Some questions addressed by:
QP:
Wave 21, WRQ
CCES: Record
 Agriculture
 Industrial / urban / natural
contamination
 Conflicts: ecology 
groundwater protection
 Climate:
quantity (spring water!)
Quality
(change in redox, input of
nutrients, physical conditions,
hygiene, etc...)
3 points to discuss
• 'WRQ' maps: CH  climate
• Natural analogues
• Lakes: integrated models
coupling: climate, physics, water quality & biology
Vertical “space-for-time” or “space-for-space” analogue
Using altitudinal shifts as a proxy for climate warming
.
Decrease in surf ace air t emperat ure wit h increasing alt it ude in Swit zerland
( based on dat a from 4 0 met eorological st at ions)
Altitude (m a.s.l.)
4000
4000
3000
6 .1 K km-1
5 .6 K km-1
3000
5 .1 K km-1
2000
2000
1000
1000
a) July 2000
0
-5
0
5
b) August 2000
10
15
20
25 -5
0
5
10
c) September 2000
15
20
Air temperature (΅C)
25 -5
0
5
10
15
20
25
Livingstone, Lotter & Kettle (2005)
.
Alt it ude dist ribut ion of 1 0 7 lakes in t he Cant on of Berne, Swit zerland
3000
Choose ~4-5 lakes covering
an altitudinal gradient, e.g.
Hagelseewli
2339 m a.s.l. / 19 m / 25x103 m2
0
Seebergsee
1831 m a.s.l. / 15 m / 58x103 m2
Hinterburgseeli
1514 m a.s.l. / 11 m / 45x103 m2
2500
(Schwarzsee
1046 m a.s.l. / 10 m / 455x103 m2 )
2000
1500
A
lt
it
u
d
e
a
.s
.l
.
[m
]
Burgseewli
613 m a.s.l. / 19 m / 53x103 m2
1000
500
0
Data from Guthruf, Guthruf-Seiler & Zeh (1999)
Impact of climate change on water quality
Lakes
- Impacts of increased water temperatures in the epilimnion
- Cyanobacterial blooms (potentially toxic)
- Impacts of a longer stratification period and a shorter period of circulation on oxygen and
nutrient concentrations
- Impacts of shifts in the timing of physical and biological events - match/mismatch
Rivers
- Impacts of increased water temperatures on fish habitat
- Impacts of a reduction in residual water flow on biota
- Impacts of an increased proportion of waste water during dry periods
- Cooling problems for large industrial complexes
Groundwater
- Impacts of a sinking groundwater table on geogenic contamination (e.g., summer of 2003)
- Increase in nutrient concentrations (e.g. nitrate)
- Changing redox conditions due to higher temperatures
- “WRQ maps” for climate change in Switzerland
International cooperation
For example, cooperating internationally in deploying high-resolution
‘clever’ monitoring involvement on a global scale, e.g. within the
expanding international network GLEON...
The Global Lake Ecological
Observatory Network (GLEON)
• A grassroots network of
– ecologists, engineers, information technology
experts
– institutions and programs
– instruments
– data
• Linked by a common cyberinfrastructure
• With a goal of understanding lake dynamics at
local, regional, continental, and global scales
gleon.org
Yuan Yang Lake, Taiwan ; photo by Matt Van de Bogert