Forests & Oceans Ecosystem services, climate change impacts & solutions

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1 Image: NASA Forests & Oceans Ecosystem services, climate change impacts & solutions Forests and Oceans: for the People, for the Climate Paris CoP21 Side Event, 8 December 2015 WWF International Prof Brendan Mackey, PhD IUCN Council, Regional Councilor for Oceania Director, Climate Change Response Program, Griffith University, Australia Image: C. Mittermeier

2 Forests & Oceans are key Earth system components Of the total emissions from human activities during the period , about 44% accumulated in the atmosphere, 26% in the ocean and 30% on land. Source: Mackey (2014) Significance, ww.significancemagazine.org February 19-23; Global Carbon Project

3 Image: S. Rees Forests & carbon

4 Forest are under multiple human pressures Source: Mackey et al. (2015) Conservation Letters DOI: /conl Loss of pre-agricultural forest cover At least 35% Remaining forest that is primary forest 36% Remaining primary forest in protected areas 22% Primary forest carbon stocks relative to secondary & degraded forests 30-70% more carbon

5 Current estimates of non-ocean global C stocks Total deforestation would increase atmospheric CO 2 by up to 100 ppm Pg C Source: IPCC AR5 WGI; House et al. (2002) Glob. Change Biol. 8,

6 Potential for tropical forests in stabilizing [atmco 2 ] Currently, estimate of emissions from deforestation & degradation account for at least 1/10 of annual greenhouse gas emissions, i.e. > 1 billion tonnes of carbon (or 3.67 billion tonnes of CO 2 ) each year 1 Stopping deforestation and degradation, plus regrowth of secondary forests, plus targeted reforestation would reduce total emissions by as much as 5 billion tonnes of carbon each year, i.e. a reduced source of 1 billion tonnes and an increased sinks of 4 billion tonnes each year Absorption of carbon by tropical forests could offset much of the release of fossil fuel carbon between now and 2050, stabilizing and then reducing [atm CO 2 ] within a few decades, and providing a bridge to a fossil-fuel-free world 2 Sources: 1 Global Carbon Project 2014; 2 Houghton et al. (2015) NATURE CLIMATE CHANGE VOL 5 DECEMBER; ScienceDaily.com

7 Image: S. Rees Forests & water

8 Forests influence regional climate: water recycling

9 Forests influence watershed hydrology: water flow & quality /clear-fell /clear fell From: State of Environment Report 1996; Image: D.Lindenmayer

10 Climate change impacts on forests Image: S. Rees

11 Climate change impacts on ecosystems Shifts in species distributions & ecosystem composition Altered process rates: photosynthesis, respiration & nutrient cycling Changed fire regimes & hydrological regimes Breakdown in co-evolved & ecological species interactions Novel ecosystems & ecosystem loss Biome shifts Changes to vegetation structure & composition Reduced/increased ecosystem productivity & carbon stocks

12 Many species face forced migration or extinction Ecoregional global concentrations of terrestrial and marine climate change vulnerable species. Source: Michela Pacifici et al. PUBLISHED ONLINE: 25 FEBRUARY 2015 DOI: /NCLIMATE2448

13 Image: U.N. Oceans

14 Ocean ecosystem-benefits Climate regulation Ocean warming dominates the increase in energy stored in the climate system, accounting for more than 90% of the energy accumulated between 1971 and 2010 Of the total emissions from human activities during the period , about 26% accumulated in the world s oceans Oceanic phytoplankton produce 50% of the world's oxygen Food Security - more than one billion people worldwide rely on the ocean for their primary source of protein Biodiversity - an estimated 50-80% of all life on Earth is found under the ocean surface Economic prosperity - if the world's seas and oceans were a national economy, they would be worth around $24 trillion, making it the world's seventh largest economy Sources: WWF (2015); Global Carbon Project (2015); UNESCO

15 Blue carbon We have overlooked the key role coastal marine ecosystems - mangroves, seagrasses and saltmarshes - play as carbon sinks and reservoirs Source: NOAA

16 Coastal ecosystem services Mangroves, tidal marshes and seagrasses support coastal water quality, healthy fisheries, and coastal protection against floods and storms Over the period , estimated losses in the value of benefits because of loss of ecosystem area were $7.2 trillion per year for tidal marshes Mangroves are estimated to be worth at least US$1.6 billion each year in ecosystem services that support coastal livelihoods and human populations around the world Source: Blue Carbon Initiative

17 Climate change impacts on oceans Altered ocean currents Rising sea levels Increase intensity of tropical cyclones Warming Ocean acidification A pteropod shell showing dissolved ridges, abrasions and cloudiness. Credit National Oceanic and Atmospheric Administration Sources: IPCC; NYT; Wikipedia; EPA

18 Solutions? Climate change will interact with many existing threats to biodiversity & ecosystems, often resulting in even greater negative impacts, e.g. weeds Therefore, key climate strategy for land and oceans is to promote natural adaptive capacity & resilience by Reducing anthropogenic stressors Protecting and restoring biodiversity Enhancing connectivity