Download Impacts - 3 - Green Resistance

Impacts - 3
Your schedules please?
Future changes: a review of impact
assessments
 Most widely used scenarios are based on emission scenarios of
IPCC. Four different narratives:
 Fossil versus renewable energy
 Regional blocks or globalized international collaboration
 Equity versus personal wealth
 Level of climate change determined by general circulation models
(GCM) that comprehensively simulate the dynamic atmospheric
processes that determine climate conditions
 Output of GCMs (w/ atmospheric carbon dioxide [ ]) – used in
different ecological models to determine impacts
 Problem: this causal chain neglects linkages and feedbacks
between processes
 More advanced models partially address this issue
2
5/5/2017
Risk to ecosystems
3
5/5/2017
Plants and vegetation
 Dynamically assigning plant types on basis of climate, soil and
disturbances, dynamic global vegetation models indicate that the world’s
ecosystems [currently sequestering ~ 25% of CO2 emissions] could
shift and become a CO2 source
 High risk of forest loss for Eurasia, eastern China, Canada, Central America,
and Amazonia
 Dependent on model used
 Warming ~ 3 C, global biosphere converts to a carbon source during the
21st century in ~ ½ the scenarios
 Warming ~ 2C -> down to 15%
 Biome studies: large shifts in vegetation for each degree of warming
 Warming ~ 3 C, ~ 35% of all vegetation in the world will change character;
impact on each type will differ [alpine and tundra: reduced 90%; tropical
forest extent: stable]
 Another study: 15 – 37% of plant species – extinct by 2050
4
5/5/2017
Extinction risk from climate change
Nature, 2004
5
5/5/2017
Climate change threats to plant
diversity in Europe, 2005
 A more reliable study – using species-specific models and
linked to changes in European biodiversity – projects late 21st
century distributions for 1,350 European plant species under
7 climate change scenarios and applied IUCN’s Red List
criteria
 Many European plant species could become severely threatened
regionally
 More than ½ could be vulnerable or threatened with extinction
by 2080
 Mountain species most sensitive; Med to Euro-Siberian region
most sensitive
6
5/5/2017
Risk from indirect impacts of CC
 Increased drought  increased fire risk
 Projected % extinctions – ranged from 1% to 43 % of
endemic species (average 12%)
 Vulnerable hotspots include the Med Basin
7
5/5/2017
Wild species and extinction
 Rapid temperature change and species
 Range shifts
 Phenology
 Disruption of natural communities
 Extinction
 Changes in physical structure and genetics
8
5/5/2017
mammals
9
5/5/2017
Vulnerability of African mammals to anthropogenic climate change under
conservative land transformation assumption. Thuiller at al. 2006
10
5/5/2017
Vulnerability of African mammals to anthropogenic climate change under
conservative land transformation assumption. Thuiller at al. 2006
 Did not consider direct effects of carbon dioxide on species
composition of grasses
 Most palatable grasses on which wildlife depends consist of
C4 grasses – well adapted to low atmospheric carbon dioxide
[ ] and dry conditions
 Increasing carbon dioxide [ ] will favor C3 grasses. These
grasses take advantage of higher carbon dioxide [ ] by
growing faster and improving their water and nutrient use
efficiency – but these grasses are less palatable
11
5/5/2017
Changes in physical structure and
genetics
 Fewer studies focus on shifts in morphology and genetics
 Both are related to temperature change
 Paleothermometers
 Woodrats - Changes in their body sizes closely aligned with changes in
temperature
 Genetic changes
 Genetically controlled photoperiod of the pitcher-plant mosquito has
changed over the last thirty years
12
5/5/2017
Genetic and plastic responses of a
northern mammal to climate change 2003
13
5/5/2017
Milder winters have allowed bark
beetles to decimate the white-bark
pine, whose nuts are a critical food
source for grizzlies. Meanwhile, there
“With milder winters affecting their food and has been a slight seasonal shift for
plants that grizzlies rely on when they
hibernation habits, they're forced into a
prepare to hibernate and when they
meat-dependent diet – putting them at
emerge in the spring, changing the
odds with humans and livestock. They
creatures' denning habits.
Latest news…Grim outlook for
grizzlies in Yellowstone region
could end up as despised as wolves.”
The result, some biologists say, is that
bears accustomed to feasting on berries
and nuts in remote alpine areas are
being pushed into a more meatdependent diet that puts them on a
collision course with the other
dominant regional omnivore: humans.
14
If a shift in public perception drives
changes in policy, grizzly bears could
be legally hunted in the Lower 48 for
the first time in nearly four decades.
5/5/2017
Will the Walrus Withstand a Warmer
World?
 In three of the last four summers,
thousands of walruses have
mysteriously come ashore in Alaska.
This unprecedented behavior
occurred when ice in Chukchi Sea
drastically retreated, leaving the
marine mammals without their
usual summertime habitat.
 100 dead baby walruses in
September 2009 on remote Alaskan
beach. How did they die?
 Facing: loss of habitat + ocean
acidification resulting in reduction
of clam and snail populations
15
5/5/2017
birds
16
5/5/2017
Climate change and birds
 Impacted through




Sea level rise,
Changes in fire regimes,
Vegetation changes,
Land-use changes
 Could eventually destroy or fundamentally change 35% of
terrestrial habitats
 Warming of 2 to 3 times the global average predicted to destroy
more than 90% of bird species’ habitat in the Arctic
 In Europe’s Med coastal wetlands, and NA waterfowl habitat
 Warming of 3 to 4 C  eliminate 85% of all world’s remaining
wetlands
17
5/5/2017
Climate change
and birds
 Initial research: more than a
1/3 of all European birds will
become extinct if species are
unable to shift to new ranges
 Red kite (lose most of its
habitat)
 Scottish crossbill (lose all its
habitat)
 Worse in Australia wet
tropics bioregion: ¾ of bird
species to extinction
18
5/5/2017
Climate change and birds
 Projections likely underestimates; have not factored the
devastating impacts of climate extremes or the indirect and
secondary effects of climate change
 As discussed: CC shift timing of natural events and species’
geographical distributions  rearranging plant and animal
communities and ecosystems and disrupting relationships
with predators, competitors, prey and parasites  altering
the makeup and functions of most if not all the world’s
ecosystems
19
5/5/2017
Non-climatic forces
 Ability to cope with rapid CC severely compromised by
added stress of ongoing non-climate-related changes
 Habitat change
 Overharvesting/overexploitation
 Pollution
 Introduction of exotic species
 Thus: one way to manage conservation of species under CC
is to abate the effects of non-climate stressors
20
5/5/2017
Permanent death
 If warming > 2 C, ~ 20% of known species will likely be
unable to adapt
 If warming > 4 C, ~ 40% of known species will likely be
unable to adapt
 Between 1.7 and 1.8 million species have been identified thus
far - ~ 340,000 and 680,000 species could face extinction
 Do not include any of the estimated 14 million unidentified
species
21
5/5/2017
consequences
 Co-extinction of interdependent species (loss of specific host




22
plants caused Singaporean tropical butterfly species to die out)
Cascading effects (extinction of a top predator, coyote, mesopredator release…)
Direct human impacts (such as?)
Complex. Uncertain. Inter-related processes.
Species-preservation planning and actions call for a more
complete and action-focused understanding of climate-plantanimal interactions. Lacking studies on threatened systems such as
desert and tundra and on threatened taxa such as amphibians
5/5/2017
What to do? – a triage approach
 (save the most with limited resources)
 Requires categorizing criteria for species, populations, communities
or ecosystems; developing plans suited to a particular region or
biome
 Sort extinction-risk species into 3 groups
 Those that will clearly become extinct w/o intervention but can be
saved relatively quickly and easily = first to receive attention
 Those needing minimal but measurable help
 The unavoidable losses – those that could only be saved with intense,
lengthy, and expensive effort and even then are unlikely to survive
 Triage plan: also consider exceptional cases (a species that is only
extant member of a family) + capacity of the species’ extinction to
cause a cascading effect (given limited knowledge); same logic
applied to habitats and communities
23
5/5/2017
What to do?
 Two approaches
 Reduce Greenhouse Gas Emissions – economically and
technologically feasible!
 Increase resilience of species and ecosystem by reducing and
removing other stresses on ecosystems and enhancing
conservation efforts
24
5/5/2017
Marine ecosystems
 Carry out ~ 50% of global primary production and support
extensive biodiversity
 Provide protein sources and livelihoods for millions of people
 Ocean warming
 Major changed already in planktonic and benthic community
composition and productivity
 Increase the depth of thermal stratification  greater barrier to the
upwelling of nutrients required for primary production from the
deeper, colder nutrient-rich waters into the sunlit upper waters
where pp occurs; expansion of ‘ocean deserts’
 Reduced upwelling  5% decrease in global oceanic primary
production with a doubling of CO2
 Ocean acidification
25
5/5/2017
Marine ecosystems
Ocean warming
 Major changed already in planktonic and benthic community
composition and productivity
 Increase the depth of thermal stratification  greater barrier to
the upwelling of nutrients required for primary production
from the deeper, colder nutrient-rich waters into the sunlit
upper waters where pp occurs; expansion of ‘ocean deserts’
 Reduced upwelling  5% decrease in global oceanic primary
production with a doubling of CO2
 Thermohaline circulation
26
5/5/2017
Marine ecosystems: ocean acidification
 the other CO2 problem
 May be as serious a problem as the more familiar greenhouse warming effect
 Currently: world’s ocean absorb on average ~ 1 metric ton of CO2 produced





27
by each person each year
Estimated: surface waters of the ocean have taken up more than 500 billion tons
of CO2, around 27 to 34% of all that generated
Carbon dioxide reacts with seawater to form carbonic acid  increasing
acidity. Already pH level in surface ocean waters have declined by ~ 0.1 units
since preindustrial times; number of H+ ions increased by 30%
Ocean pH could fall further – as much as 0.4 unit by 2100 and 0.7 by 2300.
Such changes have not occurred for at least the last 420,000 years
50-55 MYA, ocean pH did decline to level expected by 2300  extinction of
many bottom dwelling, calcifying, marine organisms (took thousands of years
for pH change)  release of massive quantities of methane from marine
sediments
5/5/2017

Oysters?

THEY have formed a succulent and
nutritious part of the human diet for
thousands of years. But a new report is
warning that plentiful supplies of oysters and
mussels could disappear over the next
century because the oceans are becoming
increasingly acidic.




28
Dr John Baxter, the co-editor of an
international report into the acidification of
the world's seas, said increasing levels of
carbon dioxide being released into the
atmosphere by industrialised countries was
gradually changing the acid level of waters
across the world.
If the trend continued, the shells of
thousands of species would be eroded and
the creatures eventually wiped out - creating
a huge knock-on effect on other fish and
marine life.
Shellfish, lobsters, certain types of plankton
at the bottom of the marine food chain and
coral reefs would also face serious ecological
damage.
The first major marine areas to be affected
are the northern oceans, which are home to
a wide variety of important marine life.
The Arctic Ocean is expected to be the first
to reach a dangerous level of acidification
with 10 per cent of its area hitting the
threshold at which damage will occur by the
end of this decade.
5/5/2017
Ocean acifidication
 The facts : A special introductory
guide for policy advisers and
decision makers
 The guide is the first product
prepared by the Ocean Acidification
Reference User Group, an initiative
of the European Project on Ocean
Acidification (EPOCA), whose role
is to work with leading scientists to
rapidly communicate key messages
to policy advisers, decision makers
and, beyond that, a mass public
audience. Production of the guide
was sponsored by Natural England
and EPOCA by leading scientists
and organizations worldwide who
freely gave their time and expertise
to create this landmark product.
29
 Questions Answered: A fresh look
at the global problem of ocean
acidification for those people who
want to know a little more
 In this guide we do four new things.
We answer some key questions
many people are now asking about
ocean acidification. We say how
sure the international scientific
community is about what is already
happening to the ocean, we discuss
what the future may hold for the
ocean in a high carbon dioxide
(CO2) world, and we explore the
consequences for all of us of what is
now happening.
5/5/2017
What I’d like you to do
 Water
 Hurricanes
 Wildfires
 Tropical forests of Amazonia
30
5/5/2017