Upload
kathleen-wilson
View
217
Download
1
Tags:
Embed Size (px)
Citation preview
The Climate Threat & Conservation
Facing Certainty & Uncertainty
T. Kittel
© 2011, T. Kittel, Institute of Arctic and Alpine Research, University of Colorado, Boulder
Niwot Ridge, Southern US RockiesSubalpine Spruce-Fir Forest
March Maximum TemperatureTrend = + 0.9=C/decade
Manifestation of Change – Land Hydrology
• Spring snowmelt
• Hydrograph shifts
Manifestation of Change – Land Hydrology
+20d later–20d earlier
Timing of spring snowmelt 1948-2000 trends
Also:• Warmer river temperatures
Manifestation of Change - Biosphere
Earliest observation dates of Common Loons in the central and northern interior of British Columbia
• Earlier Spring Events - bird migration
Common Loon arrivalBritish Columbia interior– 8 dy/decade
(p < 0.001)
Steps to Understanding – Historical Analyses• Ecological Record
61 studies of 694 species or groups of species- Root et al. 2003. Nature
Changes in spring timing of a species’ temperature-related trait
earlier later
Terrestrial –• Longer Growing Season - with earlier spring bud break• Shifts in Plant & Animal Distributions - poleward and upward
Also:
The Uncertainties – The Underlying Problem
Socioeconomic, Climate, & Ecological Systems –
• Complex systems:• Many components Highly interactive• Key processes: Span wide range of temporal & spatial scales
• Multiple forcings
• Non-linear Thresholds
Cryosphere
Biosphere
Land Surface
Bottomline -• Difficult to gather key
data • Difficult to predict
behavior
Uncertainty – Sources• Socio-economic Pathway – Emissions Uncertainty
?
Which world?– Our choice
• Climate Model Limitations
Uncertainty – Sources
“Same Conceptual Basis, Different Results”
For a given emission scenario…
Different models’ outcomes
?
A2
A2°CA2
CGCM1
HADCM2SUL MC1LPJ
• Model Uncertainty – Total Ecosystem Carbon
Uncertainty – Sources
“Same Ecology, Different Results”- at the regional level
© 2007, T. Kittel
• Total Ecosystem Carbon
Uncertainty – Sources
“Same Ecology, Different Results”- with time
© 2007, T. Kittel
For a given emission scenario… for a given climate model scenario
The Certainties – Climate
‘What do we know for sure?’ – lessons from the climate models
‘Essentially, all models are wrong, but some are useful’- GEP Box, 1987
(1) Very character of regional climates will likely change over the next decades:
– Multivariate• Higher surface temperatures – different responses for Tmin Tmax
• Regional changes in precipitation,
cloud cover (light regime), wind regimes, etc.
– In means, but in also seasonality and interannual variability
Niwot Ridge, Southern US RockiesSubalpine Spruce-Fir Forest
March Maximum TemperatureTrend = + 0.9=C/decade
• Geographic and temporal coherence in forcings & responses?
“Strong Seasonal and Location Dependence”
Niwot Ridge T(max) TrendsSubalpine ForestMarch =
+0.9=C/decade
Nov = -0.5=C/decade
Alpine TundraMONTH
– Trends will be spatially dependent – even for Landscapes
• Local landscape variation in surface interactions with atmosphere
– Trends likely not to be monotonic• As circulation patterns shift, & the system passes thresholds
– Multivariate, non-linear changes give rise to novel climates
The Certainties – Climate
(2) Probable climate changes are of a magnitude and character to be significant for populations, communities, and landscapes:
– Phenologies/life cycles
– Geographic ranges
– Ecosystem structure & function• Resilience of many ecosystems is likely to be exceeded
• With extended periods dominated by seral stages
– Species interactions out of phase: • Foodwebs, competition, pollination
Certainties – The Biosphere
– lessons from the ecological models
Red-footed Booby in MangroveGalápagos Is.
“The Forgotten Pollinators”Rufous Hummingbird
Monarch Butterfly
White-winged Dove
Arizona-Sonoran Desert Museumwww.desertmuseum.org/pollination/
Lesser Long-nosed Bat
“Nectar corridors”•Sequence of flowering
plants
Long-distance migratory pollinators•Threatened – habitat loss•Keystone species
– Changes not monotonic – • ‘Winners vs. losers’?
• New equilibrium long in coming
Certainties – The Biosphere
“The loser now. Will be later to win” – Bob Dylan (1964, The Times They Are A-Changin‘)
– The rise of novel ecosystem types
Certainties – The Biosphere
– Strong synergisms with other stressors
• Compounding effects of multiple threats
• The magnitude of uncertainties ≥ magnitude of system sensitivity
• The magnitude of what’s certain will change everything
The Lessons
Difficult for conservation action??
Conservation Strategies
Cat Tien National Park, Vietnam
Steps to Understanding –• Integrate Best Knowledge
Steps to Action –• Deal with Uncertainty• Enhance Adaptive Capacity
The Uncertainty – Coping“Get over it”
Ecosystem Futures Financial Market Dynamics
• Change perspective on it Recognize it – Be smart about it
“If we build our … strategy around the [recognition] that we’re pretty darn ignorant, we probably won’t have to wait very long for
confirmation”
- John Clements, Wall Street Journal
• “Conserve smart”
= Implement strategies that recognize & handle uncertainty
• 5 key tenets:
1. Monitor temporal dynamics & trends – develop intuition
• Historical analysis • Start monitoring as soon as get in the game,
not as an afterthought
Research & Monitoring
2. Diversify holdings – to reduce risk in any one preserve
Site Selection & Prioritization
Acting Under Uncertainty – Financial Analog
• 5 key tenets (con’t):
3. Balance goals:
• Protecting current conservation sites & •
Protecting sites with potential for adaptation
Multiple-Goal Portfolio Enhanced Adaptive Capacity
4. Save aggressively – to counter downside risk of uncertainty
• “How much is enough?” Target Redundancy
5. Rebalance portfolio • Reassess strategy Adaptive Management
Acting Under Uncertainty – Financial Analog
Steps to Action – Adaptive StrategiesEnhance Adaptive Capacity –
Adopt ‘No Regrets’ & Scenario-independent Practices
Example strategies –– Reduce vulnerability to other threats
• Habitat loss, Invasive species, Pollution
– Protect processes• Watersheds, Food webs, Life cycles
– Landscape restoration
• Value of degraded sites
– Create networks of reserves
• & Reduce barriers: ‘Porous landscapes’
• The magnitude of uncertainties ≥ magnitude of system sensitivity
• The magnitude of what’s certain will change everything
• Steps to Action –• Integrate Best Knowledge• Deal with Uncertainty• Enhance Adaptive Capacity
The Lessons
Rhinoceros Hornbill eating Strangler Fig fruits, Borneo