Global Environmental Change


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Talk given by Professor Brian Schwartz at the Bloomberg School of Public Health about the environmental changes occurring because of oil consumption, pollution and population growth. Worth the gander. The problems presented here can only be solved by collective action of all of us, a different policy direction and by reassessing our fundamental values. Without all of these things happening, life as we know it will likely come to an end in our lifetime!

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Global Environmental Change

  1. 1. Global Environmental ChangeGlobal Environmental Change Brian S. Schwartz, MD, MSJohns Hopkins Bloomberg School of Public Health Departmental of Environmental Health Sciences July 29, 2011 1 Overview • Contexts • General definitions • Key problems of GEC • For each – Problem definition and scope – Some scientific evidence – Health risks 2 © 2011. Johns Hopkins University Except where attributed 1
  2. 2. Global Environmental ChangeContexts Sustainable Development"Meeting the needs of the Meeting present generation without compromising the ability of future generations to meet their needs."Gro Harlem Brundtland, World Commission on Environment and Development (Brundtland Report) [subsequently became Director-General of WHO], 1987 3 * • Development: improving human condition in all its aspects (economic, sociopolitical, environmental) • Sustainable development: by means and to end points that are consistent with maintaining improved conditions indefinitely • Sustainable well-being: sustainable development to achieve well-being where it is p g absent and putting the maintenance & expansion of well-being onto a sustainable basis where it is being provided unsustainably today* Assistant to President Obama for Science & Technology, Director of White House Office of S & T Policy, & Co-Chair of President’s Council of Advisors on S & T 4 © 2011. Johns Hopkins University Except where attributed 2
  3. 3. Global Environmental Change Three Essential Pillars of Human Well-being• Economic conditions and processes – Employment, income, wealth, markets, trade, productive technologies• Sociopolitical conditions and processes – Law & order, national & homeland security, g governance, j justice, education, health care, science, culture, arts, liberty, privacy• Environmental conditions and processes – Air, water, soils, mineral resources, biota, nutrient cycles, climatic processes 5 The preservation and enhancement of all three are the core responsibilities of 6 © 2011. Johns Hopkins University Except where attributed 3
  4. 4. Global Environmental ChangeWhich of Three is Most Important?• Each is indispensable• Failure of any one can mean collapse of y p the human enterprise• The three interact – Economic systems cannot function without inputs from environmental system or stability provided by sociopolitical system – Societal stability cannot be maintained in the face of environmental disaster (even in the most prosperous countries) • Social disruption may be the main outcome of concern 7 The world now faces unprecedented threats to thesethree pillars – arising from resource limitations and uses – and thus to human well-being. This lecture is about trying to y g convince you about the existence and magnitude of some of those threats … 8 © 2011. Johns Hopkins University Except where attributed 4
  5. 5. Global Environmental ChangeEnvironmental Signals at Global Level• Atmospheric CO2 • Soil quality• Temperature • Pasture lands• Sea l S levels l • Storm intensity• Ecosystems • Forests• Desertification • Rangelands• Fisheries • Glaciers• Co a ee s Coral reefs • P l i caps Polar ice• Water tables • Species losses• Biodiversity losses • Toxicants in air,• Soil quantity water, soil 9 “We know from earlier civilizations that the lead indicators of economic decline were environmental,not economic. The trees went first, then the soil, and finally the i ili ti it lf To th civilization itself. T archeologists, the sequence is all too familiar.” 10 © 2011. Johns Hopkins University Except where attributed 5
  6. 6. Global Environmental ChangeThreat #1.To all three pillars. Peak oil and the coming era of energy scarcity M. King Hubbert, 1903-1989. Geophysicist. • He made a startling prediction first made public in 1949 prediction, 1949, that the fossil fuel era would be of very short duration. • In 1956 he predicted U.S. oil production would peak in 1970; he was scoffed at; he was exactly correct. Our environment problem is mainly caused by energy; our energy problem is mainly because there is not enough environment. 11 The bell- shaped curve of production – Hubbert’s Peak. Hubbert’s original estimate Scientific American, Energy and Power, 1971 Predicted world oil production would peak around 2000 It is a geologic reality that cannot be overcome with more drilling or new technology 12 © 2011. Johns Hopkins University Except where attributed 6
  7. 7. Global Environmental ChangeOil-producing Countries Past Peak Note: Hubbert’s method worked very well in 1956 to predict U.S. peak in 1970 NGL = natural gas liquids 13Monthly world oil production and prices, 2002–2010 World oil production has stalled Flat from 2005-10 while demand increased 2-5%/year Figure from Post Carbon Reader Ch 19 Data from US EIA © 2011. Johns Hopkins University Except where attributed 7
  8. 8. Global Environmental ChangeWSJ Blogs, Environmental Capital, 5/4/09 “Peak Oil: Global Oil Production’s Peaked”(Raymond James, financial & energy investment services & analysis) • Non-OPEC peaked in 2007 • OPEC and thus world, peaked in 1Q2008 OPEC, world “… contention rests on simple argument: OPEC oil production … fell … as oil prices were above $100 per barrel, a sign of the ‘tyranny of geology’ …” “… a paradigm shift of historic proportions.” Daily production vs. $ price 2003 2004 2005 20041997 2003 2005 2005 2005 2005 2006 2006 2006 2009 2007 2008 2009 2006 16 © 2011. Johns Hopkins University Except where attributed 8
  9. 9. Global Environmental ChangeOVERVIEW GLOBAL HEALTHFOOD CONFLICTPUBLIC HEALTH DEPARTMENTS URBAN FORMCOMMUNICATION HEALTH CARE 17 Implications of Peak Oil Are Myriad • Economies – high correlation between per capita GDP and per capita energy inputs • Food – our current system inefficiently converts fossil f l i t f d f il fuels into food • Water – energy and water are inter-dependent • Population – remarkable parallel between use of fossil fuels and population growth • Transportation – highly reliant on liquid fuels • Communities and built environment • Health – EMT, disaster preparedness and response, hospitals, pharmaceuticals, plastics • War – very dependent on liquid fuels • Energy security – perhaps no such thing 18 © 2011. Johns Hopkins University Except where attributed 9
  10. 10. Global Environmental Change “A Harsh Reality”• “Oil: Peaking some time in the next three years, possibly already y y y past peak• Gas: Peaking some time in the next three to 13 years• Coal: Peaking some time in the next 13 years• Nuclear: Probably peaking some time in the next 10 years, with lots 2008 of variables, but its use won’t increase substantially” 19 Resource Scarcity • Petroleum – as already covered; and energy scarcity  minerals & materials scarcity y y • Fresh water – impacted by climate change • Agricultural land – China purchasing prime farmlands in Africa • Phosphorus – US, China, Morocco possess most of the resource, already limiting exports • Rare earth elements – renewable energy • Soil – loss of top soils due to farm practices 20 © 2011. Johns Hopkins University Except where attributed 10
  11. 11. Global Environmental ChangeRelated Problem.Implications for all three pillars. The U S has the “wrong” built U.S. wrong environment. We heavily invested in a model that likely will be greatly disruptive and disrupted in the 21st Century, Century and that is already affecting public health in several ways. I will tell you more about the built environment and public health on August 8th. 21 The Key Threats to Pillars from Global Environmental Change Are LINKED• Global climate change (1) • Ecosystem destruction (3)• Stratospheric O3 depletion (2) • Biodiversity & species loss (4)… are caused by human behaviors & are a threat to health 1 2 3 WHO, 2006 4 3 22 © 2011. Johns Hopkins University Except where attributed 11
  12. 12. Global Environmental ChangeThreat #2.To all three pillars.Climate Change 23 GALLUP POLL, April 21, 2008 National Journal, Oct. 2010: “The GOP is stampeding toward an absolutist The rejection of climate science that appears unmatched among major political parties around the globe.”Rasmussen Reports, June 28-29, 2009: 41% of Americans opposed (37% infavor) to climate change and energy bill passed 219-212 along party lines inU.S. House of Representatives last month, now being considered in Senate.National Republican Congressional Committee: “Democrats ongoing crusadeagainst economic recovery.” 24 © 2011. Johns Hopkins University Except where attributed 12
  13. 13. Global Environmental Change Timelines• The planet is around 5B years old• Humans have been in settlements for around 10,000 years• Industry and its hazards have been around for approximately 200 years• Global climate change has been a concern for around 30 years (first world climate conference in 1979, Kyoto Protocol 1997)• Hottest year on record 2005; 2010 tied; 2009 2nd; 2000-9 hottest decade on record• This happened fast! 25 26 © 2011. Johns Hopkins University Except where attributed 13
  14. 14. Global Environmental Change Intergovernmental Panel on Climate Change, 2007IPCC was created in 1998; 2007 was fourth full report p “Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.” 27Tim Flannery, Australianmammologist, paleontologist, climateactivist: “… the pronouncements of the IPCC do not represent mainstream science, nor even good science, but lowest-common-denominator science – and of course even that is delivered at glacial speed. If the IPCC says something, you had better believe it – and then allow for the likelihood that things are far worse than it says they are.” 28 © 2011. Johns Hopkins University Except where attributed 14
  15. 15. Global Environmental Change • Analysis of air bubbles in Antarctic ice cores A2 • Similar data for CH4 and N2O • Atmospheric CO2 has not exceeded 300 ppm B1 in 800,000 yearsUS GCRP, 2009 29Northern Hemisphere Temperatures, Past 1,000 Years “Multiple indicators, same bottom line conclusion: consistent and unmistakable signal from the top of the atmosphere to the bottom of the oceans” 30 © 2011. Johns Hopkins University Except where attributed 15
  16. 16. Global Environmental Change A1F1 4°F / 2.2 °C Observed and projected O Simulated and projected changes in global average changes in amount of temperature, three IPCC precipitation in heaviest 5% ofscenarios, relative to 1960-79. days, relative to 1960-79.A range of models predicts 2 More severe events are to 11.5 °F. US GCRP, 2009 coming. 31Momentum in Climate System and Lag Times: CO2, temperature, and sea level continue to rise long after emissions are reduced IPCC 32 © 2011. Johns Hopkins University Except where attributed 16
  17. 17. Global Environmental Change US GCRP, 2009 A1F1 World CO2 emissions, 2008, 40% higher than in 1990 Actual emissions have been worse than even the most pessimistic IPCC projection (A1F1) 33 Examples of global emission pathways for cumulative CO2 emissions of 750 Gt, 2010-2050 (an amount with 67% probability of keeping global warming < 2°C). If world population = 9B … this is 0.5T/person (US current = 20T/person )“An important consequence of the rapidly growing emissions rate … is that any delay in reaching the peak in emissions drastically increases the required rapidity and depth of future emissions cuts.” 34 © 2011. Johns Hopkins University Except where attributed 17
  18. 18. Global Environmental ChangeHighlights• 2010 one of two warmest years on record (2005)• Weather extremes observed globally: hot, cold, wet, dry• Arctic continues to warm at twice rate of lower latitudes• Changes in ocean salinity patterns suggest increase inhydrologic cycle• Arctic sea ice extent third lowest on record since 1979(Antarctic sea ice extent near maximum)• Greenland glaciers lost more mass than in any year onrecord (10 ) d (10y)• Greenland Ice Sheet lost record mass (since 1958), area &duration of melting largest since 1978• Permafrost temperatures 2°C warmer than 20-30y ago• 2010 is 20th straight year that alpine glaciers lost mass• CO2 increased 2.6 ppm, higher than 30y average rate 35 How do we know these changes are due to human activities? Detection and attribution research 36 © 2011. Johns Hopkins University Except where attributed 18
  19. 19. Global Environmental Change IPCC, 2001; Hansen, 2011 Studying Climate • Scientists study all this complexity using: – Earth’s paleoclimate history: how did Earth respond to past changes, especially in response to boundary forcings* – M d Modern observations of climate change, coincident with b i f li h i id ih rapidly-changing human-made & natural climate forcings – Climate models and theory • To project future climate: – Use historical observations – paleoclimatology – Use computer models p • Current data to develop and validate model, then use to predict future • Also use to understand perturbations – if current model predicts current conditions well, perturb it to see how this might change outcomes of interest * Boundary forcings are factors that affect Earths energy balance (e.g., solar irradiance, ice sheet distribution, GHGs) 37 The Human Fingerprint A climate forcing is an imposed perturbation –natural or human-made –of Earths energy balanceUS GCRP, 2009 Forcings in Watts/m2 38 © 2011. Johns Hopkins University Except where attributed 19
  20. 20. Global Environmental Change Stay < 2°C (3.8°F) increase, < 450 ppm CO2 “Catastrophic Climate Change” • Sea level rise leading to g displacement of human populations (10’s – 100’s millions) • Extinction of 50% of plant and p animal species • Regional climate change with large impacts on food production and hydrologic cycle 39The Bad News About Climate Change • GHG emission trajectories over past 7 years: worse than even the worst IPCC projections • In 2010, GHG emissions highest ever • Ocean absorption of CO2 has been declining • Ice sheet melting: much faster than predicted • Coral reef bleaching accelerating • Several tipping points in climate feedbacks may soon be fully engaged – declining albedo, burning boreal forests Amazon dieback forests, dieback, melting permafrost, enhanced El Niño • Growing consensus: 450 ppm will not be safe; need to get down to 350 ppm (now 390 ppm) • To prevent < 2°C increase, emissions must start declining by 2016 40 © 2011. Johns Hopkins University Except where attributed 20
  21. 21. Global Environmental Change2007 Climate models are not needed to calculate forcings – is about chemistry and physics. Climate sensitivity (S) = equilibrium global surface temperature change (ΔTeq) in response to specified unit forcing after planet has come back to energy balance (S = ΔTeq/F). Climate sensitivity depends upon climate feedbacks – physical processes that occur as climate changes in response to a forcing0.75°C per W/m2 – that can enhance or diminish climate 3°C per 2xCO2 response.  > 2°C per W/m2 “Climate feedbacks are the core of> 8°C per 2xCO2 the climate problem.” Hansen J, 2011 41 Examples of policy-relevant tipping points (those that could occur this century due to human activities) Tipping point: critical threshold at which the future state of a system can be qualitatively altered by a small change in forcing. + Others are notdepicted (e.g., shallow water corral reefs) Copenhagen Diagnosis 42 © 2011. Johns Hopkins University Except where attributed 21
  22. 22. Global Environmental ChangeThawing permafrost above Arctic Circle Methane 23X CO2 “The Peril Below the Ice” – A Positive Feedback 43 Impacts 2008 44 © 2011. Johns Hopkins University Except where attributed 22
  23. 23. Global Environmental ChangeTemperatureSea level risePrecipitation IMPACTS ON … Species & Water Coastal natural Health Agriculture Forest resources areas areas 45 1. Global warming is unequivocal and primarily human-induced 2. Climate changes are underway in the U.S. and are projected to grow 3. Widespread climate-related impacts are occurring now and are expected to increase 4. Climate change will stress water resources 5. Crop and livestock production will be increasingly challenged2009 46 © 2011. Johns Hopkins University Except where attributed 23
  24. 24. Global Environmental Change 6. Coastal areas are at increasing risk from sea-level rise and storm surge 7. Risks to human health will increase 8. Climate change will interact with many social and environmental stresses 9. Thresholds will be crossed, leading to , g large changes in climate and ecosystems 10.Future climate change and its impacts depend on choices made today2009 47 Climate Change & Public Health • More heat-related illness • Worsening air quality • Rising sea levels • More accidents and injuries from increased flooding, storm surge, and extreme weather • Greater risk of infectious diseases • Threatened quantity & quality of water supplies • Threatened food supplies • Stressed ecosystems, potential for collapse, and St d t t ti l f ll d loss of ecosystem services • Vulnerable populations • Environmental refugees, social disruption, conflict 48 © 2011. Johns Hopkins University Except where attributed 24
  25. 25. Global Environmental Change Warmer Temperatures are Here Heat-related morbidity and mortality – a direct health effect of climate change Nature 2004: Summers like this in Europe will happen every other year by 2040Summer 2003 35,000 dead 49 Example: Climate on the Move – Changing Summers Projections of summer average temperature and precipitation changes (mid = 2040 59 end = 2080 99) 2040-59, 2080-99) Translates into considerably HOTTER and DRIER summers in both locations. Many other similar regional impacts have been forecast: e g water levels e.g., in Great Lakes, coastal erosion, insect infestations, drought and flood risks US GCRP, 2009 50 © 2011. Johns Hopkins University Except where attributed 25
  26. 26. Global Environmental Change Conrad Icefield and Glacier Purcell Mountains British Columbia Melting, melting, melting … 51 US GCRP, 2009 Conrad Icefield and Glacier Purcell Mountains British ColumbiaCubic miles of glacier ice loss 52 © 2011. Johns Hopkins University Except where attributed 26
  27. 27. Global Environmental Change Retreating Margin of Larsen B Ice Shelf, 1998- 2002 Red squares indicate glacier velocity measurement sites where speed increased up to 5X faster in 12 mo after 2002 ice shelf breakup 53 54 © 2011. Johns Hopkins University Except where attributed 27
  28. 28. Global Environmental Change Rate of Greenland ice melting doubled from 1996-2005 Moulin (NASA photo) 55 Arctic Climate Impact Assessment 11/2004Arctic Sea Ice Observed September 1979 (first data) Observed September 2003 ----------------------------- PROJECTIONS---------------------------- 2010-2030 2040-2060 2070-2090 Telegraph, UK, Apr 2009: “Scientists say Arctic could be ice-free within decade” 56 © 2011. Johns Hopkins University Except where attributed 28
  29. 29. Global Environmental Change SoTC10: ARCTIC “Changes occurring faster than in most of rest of world. Trends in snow cover duration, permafrost, & vegetation continued or accelerated.” Updated to 2008 (Copenhagen Diagnosis) 2008 57• IPCC: sea level projectedto rise 7-23 in by 2100*• Hansen: paleoclimate datasuggest that sea l t th t level will l illrise > 20 ft (6 m) with 2°C  * … excluding future rapid dynamical changes in ice flow & melting58 © 2011. Johns Hopkins University Except where attributed 29
  30. 30. Global Environmental ChangeRising Temperatures Warmer temperaturesWorsen Air Pollution increase tropospheric ozone formation This has been linked to asthma and cardiovascular disease hospitalizations and deaths 59 Dengue Malaria Lyme disease Some pests will thrive with change in climate: vector-borne disease risk 60 © 2011. Johns Hopkins University Except where attributed 30
  31. 31. Global Environmental Change Extreme Events IPCC, 2007: Climate change will result in more weather extremes – more heavy precipitation events, floods, droughts, stronger hurricanes (“climate chaos”) • Regional extremes are very important to public health • More relevant to people; largest impact on communities •MMore difficult t model – greater variability on smaller diffi lt to d l t i bilit ll scales & resolution of current models an issue • Much progress being made • Regional extremes attribution improving and projections are concerning 61 Katrina3-dayaverage seasurface T°Yellow,Yelloworange, andred areas are> 82° F(27.8° C, theT° needed forhurricanes tostrengthen).Min 26° Cneeded forhurricanes toform. Epstein P. NEJM 2005; 353: 1433-6. 62 © 2011. Johns Hopkins University Except where attributed 31
  32. 32. Global Environmental Change Hurricane projections to 2080 for 1% annual increases in CO2 levels 63Just As the Challenges of Peak Oil Arrive, Climate Change Will Constrain Energy Production US GCRP, 2009: • Energy production is likely to be constrained by rising temperatures and limited water supplies in many regions • Energy production and delivery systems are exposed to sea-level rise and extreme weather events in vulnerable t th t i l bl regions • Climate change is likely to affect some renewable energy sources (e.g., hydropower) 64 © 2011. Johns Hopkins University Except where attributed 32
  33. 33. Global Environmental Change 2008• Water is needed to generate energy – veryimportant and large quantities• Energy is needed to deliver water• These resources already limit the other –increasing examples• Switching from gasoline to electric vehicles orbiofuels is a strategic decision to switchdependence from foreign oil to domestic water• Complex inter-connectedness – our theme Linkages between My sick joke is that Eastern Australia had average rainfall for the last seven years. The first six were the climate change, driest six years in the record books, and the seventh ecosystems, was feet deep in unprecedented floods. Such y “average” rainfall makes farming difficult. food and Jeremy Grantham, GMO LLC, May 2011 production Meeting needs for increased agricultural production has the potential to increase global rates of biodiversity loss, climate change, & desertification. 66 © 2011. Johns Hopkins University Except where attributed 33
  34. 34. Global Environmental ChangeSummers in 2080-2100 Warmer than Warmest on Record • Compared these temperatures to historical ones and their impacts on agriculture • Crop yields declined 20-50% at these temperatures • There will be food deficits in many parts of world • Tropics most susceptible • Most of world lives in these p places • Adaptation may help, must start now Using summer means (minimizes tails, thus under-estimating effect) 67 An Equation for Disaster Forced migration of millions + Scarce resources, including energy + Shrinking economies + Already stressed infrastructures and ecosystems = Conflict• Wars over food, land, water, energy, environmental refugees?• Each would have severe implications for population health. 68 © 2011. Johns Hopkins University Except where attributed 34
  35. 35. Global Environmental Change Environmental ConflictsTEEB, 2008 69 So, to review, and in summary … 70 © 2011. Johns Hopkins University Except where attributed 35
  36. 36. Global Environmental Change 71 2009 dataUS: 5% population, 18% GHG emissions 72 © 2011. Johns Hopkins University Except where attributed 36
  37. 37. Global Environmental Change Deaths Attributed to ClimateChange (selected outcomes only)WHO data for 2000; for cardiovascular diseases, diarrhea, malaria, inlandand coastal flooding, and malnutrition.In 2000 – 150,000 deaths Patz J, et al. Nature 2005; 438: 310-7. 73 1995 Nobel Prize in Chemistry Stratospheric ozone depletion Some slides from Pyle JA, Solomon S. IPCC WG1, obtained from July 19 2006 74 © 2011. Johns Hopkins University Except where attributed 37
  38. 38. Global Environmental Change The Small BiosphereEarth diameter = 8,000 Karman line (“edge ofmiles space”) = 62 milesBiosphere (layer inwhich life can be found)= 8 milesStratospheric ozone 75 Stratospheric Ozone • Most O3 in lower stratosphere, 15-25 km • Began accumulating 1-2B y agoago, product of photosynthesis in aquatic algae & plants • O2 is converted to O3 by high-energy photolytic action of UV radiation – Cl* from CFCs catalyze breakdown of O3 Cl • Ozone layer blocks out all UV-C, 50% of UV-B, and small fraction UV-A* • T1/2 for ozone regeneration: 3-4 y* Wavelengths: UVA 400 nm - 320 nm; UVB 320 nm - 290 nm; UVC 290 nm - 100 nm 76 © 2011. Johns Hopkins University Except where attributed 38
  39. 39. Global Environmental Change Chlorofluorocarbons (CFCs) • DuPont, first synthesized 1928 • CFC-12 (R-12), DuPont trade name ( ), Freon – Primary use as refrigerant in residential refrigerators and mobile air conditioners • CFC-11, 113, 114, 115 used in production of other products – Foam rubber (blowing agents), rigid insulating foam, solvents in electronics industry 77 CFCs and Ozone• 1974: Molina & Rowland, two American scientists, hypothesize CFC role in Nature• 1978: U.S. bans use in spray cans 9 8 U S ba s sp ay ca s• 1983: Scandinavians propose global ban• 1985: Vienna Convention – 20 nations sign; declaration, not commitment – Precedent: multinational agreement on environmental problem before clear scientific consensus – In 1985, there was no evidence that CFCs actually damaged stratospheric ozone! 78 © 2011. Johns Hopkins University Except where attributed 39
  40. 40. Global Environmental Change Potential Effects of Ozone Depletion • Direct health effects – SKIN: damage, cancer (10% loss, for 40 years, 300,000 new cases non-melanocytic skin cancer, 5,000 9,000 new cases cancer 5 000-9 000 melanoma) – EYE: cataracts, conjunctival epithelial thickening, ? retinal degeneration – IMMUNE system: ? immunosuppression • Indirect effects – Crop yields, forest growth – Phytoplankton reduction (under hole, 10% ) – Positive feedback to global warming (GW increases ozone depletion which enhances GW) 79Regions of the world by latitude90°60°30°0°3030°60°90° 80 © 2011. Johns Hopkins University Except where attributed 40
  41. 41. Global Environmental Change Early Observations• 1985: British scientists – 40% loss of Antarctic ozone in late winter and early spring• 1986-7: losses reported over both poles, late winter• 1988: inverse correlation measured between stratospheric CFC & O3• 1980s: measured 50% increase in CFC levels• 1988: new report, two important conclusions – (1) Antarctic O3 hole caused by CFCs; and (2) O3  observed in North Temperate Zone – Industrial opposition to CFC phase out disappeared; DuPont switches within 2 weeks• 1980-92: at 30-50° N, O3 decreased 0.5%/y• 1980s & 1990s: UV levels measured by satellite – s of 5% per decade at 30° N and 30° S; 15% per decade at 55° S; 40% per decade over Antarctic; 10% per decade over Arctic 81 Measured 82 © 2011. Johns Hopkins University Except where attributed 41
  42. 42. Global Environmental ChangeSo, good news for the world. But not all the news is good. 2/3 of world total gone by 2065 NASA simulation – a world without controls on Cl & B pollution i l ti ld ith t t l Br ll ti With controls, recovery was expected by 2050 “Amid the good news … lurk big questions about how long it will take … A decade ago, researchers projected … fully recover by 2050 … now … far more uncertainty. One … complicating factor … GHGs have altered atmospheric conditions … since Montreal Protocol was signed, some of which speed up ozone recovery and some of which delay it.” 83 WMO & UNEP: > 700,000 excess cases 1980-2050 due to ozone depletion • MeBr pesticide still being used (was supposed to be phased out by 2005 in developed countries), after lobbying efforts • Cl- and Br-containing compounds in old air conditioners and fire- fighting sys e s e pec ed to make it g g systems expected o a e to atmosphere as these break down • Br levels in stratosphere are higher than expected and than levels used in models 84 © 2011. Johns Hopkins University Except where attributed 42
  43. 43. Global Environmental Change World Response Summarized • 1985: Vienna Convention • 1987: Montreal Protocol on Substances that Deplete the Ozone Layer – 50% phase out of CFCs by 1998 • 1990: London Revisions – Added new compounds, financial mechanisms for aiding developing countries, added new control measures • 1992: Copenhagen Amendment – Added HCFCs, HBFCs, and MeBr • 1997: Montreal Amendment – Licensing systems for control & monitoring of substances under agreements • 1999: Beijing Amendment – New compounds, new control measures, new restrictions on trade • Virtually all countries have ratified these treaties 85 Compare & ContrastOzone Depletion & Climate Change • Both are global in scale • Both pose significant potential risks to inhabitants of this planet, both direct and indirect • Both with significant sources of uncertainty and natural variability • Both required complex computer modeling • Both have generated considerable, rancorous hh d d bl debate • One was “solved” before scientific consensus • The other – the heated debate continues 86 © 2011. Johns Hopkins University Except where attributed 43
  44. 44. Global Environmental Change Ecosystem destruction 87 Millennium Ecosystem Assessment• 1400 experts from 95 countries• S Spent 4 years conducting a global t d ti l b l inventory of the state of our ecosystems• Quantifying the effect that human activities are having on them (and on the impacts of ecosystem changes for human well being) well-being)• Identifying information gaps• Making suggestions for the future• Results released April 2005 88 © 2011. Johns Hopkins University Except where attributed 44
  45. 45. Global Environmental Change Millennium Ecosystem Assessment Findings • 60 per cent of the planets ecosystem services are currently being degraded by human activities • 20 per cent of the worlds coral reefs have been lost • 40 per cent of the planets rivers have been fragmented 89Human Activities that Degrade Ecosystems• Runoff of pesticides, fertilizers, and animal wastes• Pollution of land, water, and air resources• Introduction of non-native species• Over-harvesting of fisheries• Destruction of wetlands• Erosion of soils• Deforestation• Urban sprawl Ecological Society of• Ecosystem fragmentation America, 2000 90 © 2011. Johns Hopkins University Except where attributed 45
  46. 46. Global Environmental Change Ecosystem Impacts• Deforestation• Coastal wetlands• Marine fisheries• Coral reefs• Desertification The coming era of energy, water, and food scarcity 91 Example: Marine Fisheries • Ocean acidification • Over-harvesting • Pollution runoff from land • Destructive practices • Warming oceans 2009• Bottom trawlers withenormous nets• 20 lbs bykill for eachlb catch• Up to 55% coral,67% spongesdestroyed in singledrag• Area larger than CAalready destroyed byU.S. trawlers Seafloor destruction plume Satellite view, Gulf of Mexico 92 © 2011. Johns Hopkins University Except where attributed 46
  47. 47. Global Environmental ChangeEcosystem Services Ecological Society of America, 2000 • Moderate weather extremes and impacts • Disperse seeds • Mitigate droughts and floods • Protection from ultraviolet rays • Cycle and move nutrients • Protect streams, rivers, & coasts from erosion • Detoxify and decompose wastes • Control agricultural pests • Maintain biodiversity • Generate & preserve soils & renew fertility • Contribute to climate stability • Purify air and water • Regulate disease carrying organisms • Pollinate crops and natural vegetation 93 Images: 1921 2007 Mount Everest & Main Rongbuk Glacier, Tibet Autonomous Region, China, 1921-2007The “Third Pole” – Greater Himalayas and Tibetan Plateau: the largest non- polar ice mass in the world A critical ecosystem function: collect and store monsoon rains Feeds ten major rivers in Asia: Yellow, Yangtze, Mekong, Salween, Irrawaddy, Brahmaputra, Ganges, Indus, Amu Darya, and TarimTotal flow from glacier melt: Indus 50%, Tarim 50%, Yangtze 18%, Salween 9% But melt waters can account for up to 70% of spring and fall flows for each © 2011. Johns Hopkins University Except where attributed 47
  48. 48. Global Environmental Change Energy  Climate  Ecosystems• Energy issues, climate change, and ecosystem issues are intricately interlinked• To date, our ecosystem issues have looked less severe because we have used cheap energy to overcome o e come them• Climate change is now an overarching set of challenges on top of all ecosystem issues 95Biodiversity and species loss 96 © 2011. Johns Hopkins University Except where attributed 48
  49. 49. Global Environmental ChangeFirst sighted RIP Mauritius EXTINCT c. 1580 c. 1681 The dodo bird 97 The first human-caused extinction5 Mass Extinctions • Ordovician Mass extinction: – Cause: glaciation Earth loses 75% of species in • Devonian geologically short – 70% of all species time interval – Cause: global cooling • Permian – Largest extinction event – 96% of all marine species, 75% of terrestrial families – Cause: Siberian volcanism & warming • Triassic – ~25% of all families, many vertebrates – Cause:  CO2, warming, acidification • Cretaceous – Most famous – dinosaurs – 85% of all species – Cause: meteorite impact theory remains the most probable 98 © 2011. Johns Hopkins University Except where attributed 49
  50. 50. Global Environmental Change The 6th Mass Extinction Caused by Humans• >16,000 species currently threatened with extinction – 100 to 1,000 times the “normal” background rate of species extinction – In last 500 y, 844 extinctions due to human activity – Numbers of threatened species are increasing• Different from previous – No cataclysmic natural event – Caused by humans 99 4 3 2 1 100 © 2011. Johns Hopkins University Except where attributed 50
  51. 51. Global Environmental ChangeMean Species Abundance TEEB, 2008 1970 Arose out of G8+5 environment ministers meeting in Potsdam, FRG, May 2007 Major continuing impacts, with additional 11% average losses 2050 2000-50, with > 20% in some biomes, especially in Africa, India, China. (% of original land biodiversity) 101 Convention on Biological Diversity • Came from Earth Summit in 1992 – U.S. signed 1993 • The variability among living organisms from all sources including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part. This includes diversity within species, between species and of ecosystems (CBD, 2002). 102 © 2011. Johns Hopkins University Except where attributed 51
  52. 52. Global Environmental Change Key Messages• Biodiversity has many benefits for humans• Declines in biodiversity due to human activities over the past 50 y have been rapid and unprecedented in human history• The main drivers of change are getting worse & are likely to co t ue or accelerate ey continue o acce e ate• An unprecedented effort would be needed to achieve (by 2010) a significant reduction in the rate of biodiversity loss at all levels 103 104 © 2011. Johns Hopkins University Except where attributed 52
  53. 53. Global Environmental Change The world’s ocean is at high risk of entering a phase of extinction of marineJune 2011 species unprecedented in human history Examined combined effects of pollution, acidification, ocean warming, over-fishing, and hypoxia. warming over-fishing hypoxia The panel concluded that: • The combination of stressors … is creating conditions associated with every previous major extinction … in Earth’s history • The rate of degeneration … is far faster than … predicted • Many … negative impacts previously identified are greater than the worst predictions • … the first steps to globally significant extinction may have begun with a rise in the extinction threat to marine species such as reef-forming corals 105 Bleaching as coral expel algae Coral reefs: 0.2% of ocean floor; 25% of ocean’s biodiversity; key source of protein for 500M people, protect coastal shores from weather & tsunamis World Resources Institute: 75% of world’s reefs at risk Global Coral Read Monitoring Institute: 20% of world’s reefs lost Warming seas, ocean acidification expected to put all world’s reefs at risk by 2050 © 2011. Johns Hopkins University Except where attributed 53
  54. 54. Global Environmental Change Parting Words Climate change + energy scarcity: the canvas on which the history of h h h h h f the 21st Century will be painted.* Climate change is likely to be the predominant scientific, economic, political and moral issue of the 21st century. The fate of humanity and nature may depend upon early recognition and understanding of human-made effects on Earths climate. James E. Hansen, NASA Goddard Institute for Space Studies, 2011 * Adapted from Mark Lynas 107“The Perfect Storm”Challenges Responses Outcomes Conflict Ecosystem & The “wrong” built Geopolitics ofspecies declines environment scarcity Refugees Climate change Deficits Competition SocialThe coming era of Huge fossil fuel over resources upheaval energy scarcity inputs into food production Population Other resource scarcity morbidity Population P l ti mortality (Workable solutions) (Sustainability) 108 © 2011. Johns Hopkins University Except where attributed 54
  55. 55. Global Environmental Change We the undersigned, senior members of the world’s scientific community, hereby warn all humanity what lies ahead. ahead A great change in our stewardship of the earth and life on it is required if vast human misery is to be avoided and our global home on this planet is not to be irretrievably mutilated. The World’s Scientists’ Warning to Humanity, 1992 (1,700 scientists signed, 104 Nobel laureates) 109Australia, Saudi Arabia 2006 Brazil 1.9 Indonesia 1.6 Pakistan 0.8 Nigeria 0.6 Total emissions #1 #2 From 2002-2006, per capita emissions increased from 2.1 to 4.6MT/y in China. World average increased by ~15%. 110 © 2011. Johns Hopkins University Except where attributed 55
  56. 56. Global Environmental Change An Editorial• There is a lot we can do NOW with technology … but not much happening• While we are waiting for p g political, , business, and public health leaders to act …• … what can WE do now?• American behaviors are the biggest cause of this problem• The challenges presented today may b h h ll d d be the most difficult humanity has ever faced• The threats to human health and well- being are potentially catastrophic 111 Which future do you prefer? Is this a false choice or real? Scientific American 2006 112 © 2011. Johns Hopkins University Except where attributed 56
  57. 57. Global Environmental Change Remember: We have NOT EVEN TRIED YET 113 © 2011. Johns Hopkins University Except where attributed 57