Impacts - 3

1. Impacts - 3 Your schedules please?

2. 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

3. Risk to ecosystems

4. 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

5. Extinction risk from climate change Nature, 2004

6. 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

7. 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

8. Wild species and extinction • Rapid temperature change and species • Range shifts • Phenology • Disruption of natural communities • Extinction • Changes in physical structure and genetics

9. mammals

10. Vulnerability of African mammals to anthropogenic climate change under conservative land transformation assumption. Thuiller at al. 2006

11. 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

12. 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

13. Genetic and plastic responses of a northern mammal to climate change - 2003

14. Latest news…Grim outlook for grizzlies in Yellowstone region Milder winters have allowed bark beetles to decimate the white-bark pine, whose nuts are a critical food source for grizzlies. Meanwhile, there has been a slight seasonal shift for plants that grizzlies rely on when they prepare to hibernate and when they emerge in the spring, changing the creatures' denning habits. 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 meat-dependent diet that puts them on a collision course with the other dominant regional omnivore: humans. 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. “With milder winters affecting their food and hibernation habits, they're forced into a meat-dependent diet – putting them at odds with humans and livestock. They could end up as despised as wolves.”

15. 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

16. birds

17. 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

18. 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

19. 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

20. 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

21. 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

22. consequences • Co-extinction of interdependent species (loss of specific host 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-plant-animal interactions. Lacking studies on threatened systems such as desert and tundra and on threatened taxa such as amphibians

23. 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

24. 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

25. 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

26. 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

27. 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 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

28. 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. • 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.

29. 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. • 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.

30. What I’d like you to do • Water • Hurricanes • Wildfires • Tropical forests of Amazonia