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John Holdren on Climate Change Challenge 2018 02-15

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In Nantucket I attended an amazing and scary presentation by John Holdren on Climate Change. John Paul Holdren was the senior advisor to President Barack Obama on science and technology issues through his roles as Assistant to the President for Science and Technology, Director of the White House Office of Science and Technology Policy, and Co-Chair of the President’s Council of Advisors on Science and Technology (PCAST).

Holdren was previously the Teresa and John Heinz Professor of Environmental Policy at the Kennedy School of Government at Harvard University, director of the Science, Technology, and Public Policy Program at the School's Belfer Center for Science and International Affairs, and Director of the Woods Hole Research Center.

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John Holdren on Climate Change Challenge 2018 02-15

  1. 1. John P. Holdren Professor of Environmental Science and Policy Harvard University Senior Advisor to the Director Woods Hole Research Center Former Assistant to President Obama for Science & Technology and Director, Office of Science & Technology Policy Executive Office of the President of the United States Brown University February 15, 2018 Essence of the energy-climate challenge • Without energy there is no economy • Without climate there is no environment • Without economy and environment there is no material well-being, no civil society, no personal or national security Watson Distinguished Speaker Series Institute at Brown for Environment and Society Watson Institute for International and Public Affairs •
  2. 2. 2/15/2018 2 That term implies something… • uniform across the planet, • mainly about temperature, • gradual, • quite possibly benign. This seems to have confused people. What’s actually happening is… • highly nonuniform, • not just about temperature, • rapid compared to capacities for adjustment • harmful for most places and times A more descriptive term is “global climate disruption”. A few basics Terminology: “global warming” is a misnomer The changes are not just about temperature. Climate = weather patterns, meaning averages, extremes, timing, and spatial distribution of… • yes, hot & cold, but also… • cloudy & clear • humid & dry • drizzles, downpours, & hail • snowfall, snowpack, & snowmelt • breezes, blizzards, tornadoes, & typhoons Climate change entails disruption of the patterns. Global average T is just an index of the state of the global climate system as expressed in these patterns. Small changes in the index correspond to big changes in the system (much like your body temperature). A few basics
  3. 3. 2/15/2018 3 When the average of any of these weather variables changes, the extremes change much more. A few basics Original climate Altered climate Temperature The principle holds for any “normally distributed” climate variable: A modest change in the average  big changes at the “tails”. Climate governs (so altering climate affects) • availability of water • productivity of farms, forests, & fisheries • prevalence of oppressive heat & humidity • formation & dispersion of air pollutants • geography of disease • damages from storms, floods, droughts, wildfires • property losses from sea-level rise • expenditures on engineered environments • distribution & abundance of species Changes--in averages & extremes--matter because… A few basics
  4. 4. 2/15/2018 4 Outline of the rest of the presentation WHAT WE KNOW (beyond a reasonable doubt) ABOUT… • the pace, character, & causes of climate change • the ongoing impacts on people & ecosystems WHAT WE EXPECT • Scientific best estimates under specified future emissions • What else could happen (probability/timing uncertain) WHAT WE CAN DO • reducing emissions (how much, how fast, by whom) • adapting to unavoidable change (acting locally) • the need for (and current lack of) federal leadership • what states, cities, businesses, NGOs, & citizens can do What We Know “Everyone is entitled to his own opinion, but not his own facts.” Daniel Patrick Moynihan
  5. 5. 2/15/2018 5 Global-average surface air temperature from 1880 2016 was the hottest year on record, 2017 2nd hottest, 2015 3rd hottest, 2014 4th hottest. Shaded rectangles are decadal averages; from the 1960s, each has been warmer than the last. Earth has been warming more or less steadily for the last 100+ years, as the increasing forcing from the human-caused GHG buildup came to dominate natural variability. What we know: The pace & character of change The Arctic, West Antarctic Peninsula, and mid-continents are warming much faster than the global average NASA What we know: The pace & character of change
  6. 6. 2/15/2018 6 Arctic sea-ice extent 1979-2017: it’s shrinking Inset shows Arctic vs global T rise 1880-2017 What we know: The pace & character of change Antarctic sea-ice is in trouble, too 2002-2015 What we know: The pace & character of change Sea-ice loss in Antarctic allows the land ice to flow into the sea.
  7. 7. 2/15/2018 7 Muir Glacier, Alaska, 1941-2004 NSIDC/WDC for Glaciology, Boulder, compiler. 2002, updated 2006. Online glacier photograph database. Boulder, CO: National Snow and Ice Data Center. August 1941 August 2004 Glaciers worldwide have been shrinking for decades What we know: The pace & character of change The Greenland ice sheet has been losing mass at rates of 100-500 billion tons per year Hansen Expert Opinion 2017 What we know: The pace & character of change
  8. 8. 2/15/2018 8 The Antarctic Ice Sheet is likewise losing mass Hansen Expert Opinion 2017 What we know: The pace & character of change The pace of sea-level rise is increasing WMO 2017 Monthly values 3-month running mean 1992-2016 trend = 3.3 mm/yr 2010-2016 trend = 6.0 mm/yr What We Know: The pace & character of change Increases result from ice additions, thermal expansion, and groundwater depletion.
  9. 9. 2/15/2018 9 What We Know: The Causes of Recent Climate Change “Science is true whether or not you believe in it.” Neil DeGrasse Tyson https://fractionalflow.files.wordpress.com/2014/10/fig-1-world-total-energy-consumption-1800-to-2013.png Growth of world population & prosperity from 1850 to 2015 led to a 22-fold increase in energy use. Units are million tonnes of oil equivalent per year In 2015 the world still depended on coal, oil, & natural gas for about 80% of its total energy supply and two-thirds of its electricity. What we know: Causes of climate change
  10. 10. 2/15/2018 10 IPCC AR5 SYN Fig SPM-1 Civilization’s CO2 emissions tracked the rise of fossil-fuel use & deforestation Global anthropogenic CO2 emissions The H2O stays in the atmosphere only briefly, so the additions do not accumulate there. But much of the CO2 stays long and accumulates. Roughly, coal is CH, oil is CH2, natural gas is CH4, and wood is CH2O. In each case, their combustion produces CO2 and H2O, all going into the atmosphere. What we know: Causes So the atmosphere’s CO2 content grew markedly Updated from IPCC AR4, WG1 SPM, 2007 The record of CO2 content over the millennia (from ice cores, large curve) shows the gradual rise from the Agri- cultural Revolution and the steep one from the Industrial Revolution. The 2016 CO2 concen- tration was 403 ppmv, 45% higher than 1750. The “forcing” (scale on the right) is the resulting change in CO2 vs time from ice cores & direct measurement What we know: Causes the energy balance of the atmosphere since 1750.
  11. 11. 2/15/2018 11 Humans have added other heat-trapping gases too USGCRP 2017 Most important are methane (CH4) & nitrous oxide (N2O) from energy systems & agriculture and (most recently) CFCs & HFCs from consumer products & industry The forcing from the non-CO2 gases is smaller than that from CO2, but not insignificant. What we know: Causes Human well-mixed GHGs Net human influence Human particulates + short-lived GHGs Solar variability + volcanoes IPCC AR5, WG1 SPM, 2013 T (C) Within measurement & analytical uncertainties, essentially all of the recent observed warming was human-caused. The wafflers’ claim there’s a lot of uncertainty about the human role is wrong. Human vs natural influences on T 1950-2010 What we know: Causes
  12. 12. 2/15/2018 12 °C depar- ture from 1960-90 average Marcott et al. SCIENCE vol 339, 2013 Blue band is one-sigma uncertainty range (68% confidence interval). Natural influences—mainly variations in Earth’s orbit and axis of rotation—were in a long-term cooling phase that would have continued for 1000s of years more but for the influence of humans. Humans are clearly the cause; nature was heading the other way. Years before present What we know: Causes What We Know: Ongoing Impacts on People and Ecosystems “The debate about when climate change becomes dangerous should be over. It’s already dangerous.” John Holdren
  13. 13. 2/15/2018 13 Serious harm from climate change is here now Around the world we’re seeing, variously, increases in • floods • drought • wildfires • heat waves • coral bleaching • coastal erosion & inundation • power of the strongest storms • permafrost thawing & subsidence • expanding impacts of pests & pathogens • altered distribution/abundance of valued species All plausibly linked to climate change by theory, models, and observed “fingerprints”, most worsening faster than projected. What we know: Ongoing impacts on people and ecosystems Growing harm: Heavier downpours  more floods Percentage increase, between 1958 and 2012, in the amount of precipitation falling in the heaviest 1% of precipitation events in each region. By far the biggest increase was in the Northeast. Source: USGCRP, Assessment of Climate Change Impacts in the United States, May 2014 What We Know: Ongoing impacts on people and ecosystems A warmer atmosphere holds more water, so more can (and does) come down at one time.
  14. 14. 2/15/2018 14 East Baton Rouge, LA, August 2016: Up to 20 inches of rain in 3 days Downpours  Floods (continued) “Hundred-year” floods now occur once a decade or more in many places. Three “five-hundred-year” floods occurred in Houston in three years. Hurricane Harvey brought >50 inches of rain over 5 days to parts of Texas in August 2017. What we know: Ongoing impacts on people and ecosystems Credit: Ken James / Bloomberg California’s Folsom Lake at 17% capacity, 02-02-14 Growing harm: In a wetter world overall, many drought-prone regions are getting more so! What we know: Ongoing impacts on people and ecosystems
  15. 15. 2/15/2018 15 Growing harm: drought (continued) • Higher temperatures = bigger losses to evaporation. • More of the rain falling in extreme events = more loss to flood runoff, less moisture soaking into soil. • Mountains get more rain, less snow, yielding more runoff in winter and leaving less for summer. • Earlier spring snowmelt also leaves less runoff for summer. • Altered atmospheric circulation patterns can also play a role. What we know: Ongoing impacts on people and ecosystems Growing harm: Drought in the Amazon WMO 2017 Precipitation index for Brazil, 1/15 – 12/16 What we know: Ongoing impacts on people and ecosystems The Woods Hole Research Center is a leader in work on drying & burning in the Amazon.
  16. 16. 2/15/2018 16 0 2 4 6 8 10 12 1983 19841985 1986 1987198819891990 1991 19921993 1994 19951996 19971998 19992000 2001 20022003 2004 2005200620072008 20092010 2011 2012 20132014 2015 Data from National Interagency Fire Center Growing harm: Wildfires Millions of acres burned annually in U.S. wildfires 6 4 2 0 1981 - 2015 What we know: Ongoing impacts on people and ecosystems 10 8 Contributing factors are heat, drought, more dead trees killed by pests, and more lightning in a warming world. Update: 2016 was 5.5 M acres, 2017 was 10.0 M acres Wildfires (continued) • The fire season in the USA is about 3 months longer than it was 40 years ago. • The average fire is much bigger & hotter than before. Small wildfires burn at 1300- 1400F; big ones can burn at 2000F or more, spreading faster, with far greater risks for firefighters. • In Alaska, even the tundra has experienced wildfires in recent years. • The smoke from today’s big wildfires can carry health- harming fine particulates thousands of miles. What we know: Ongoing harm
  17. 17. 2/15/2018 17 Wildfires (continued): Smoke spreads nation-wide What we know: Ongoing impacts on people & ecosystems Fine particulate matter (PM-2.5) from wildfires is a serious health hazard. Growing harm: huge increase in heat waves 34 Probability distribution for Jun-Jul-Aug temperature anomaly on land in the Northern Hemisphere. Baseline normal distribution is for 1951-80. Standard Deviations Hansen at al., PNAS, 2012 Portion of Northern Hemisphere land experiencing > 3σ summer heat in a given year increased from 0.1-0.2% in 1951-80 to 10% in 2001-2011—a 50- to 100-fold increase. What we know: Ongoing impacts on people and ecosystems
  18. 18. 2/15/2018 18 Growing harm: More N hemisphere winter extremes Scientific American blog, January 2014 Rapid Arctic warming weakens/slows polar vortex. Resulting wavy jet stream alternating, slow- moving southward incursions of cold air and northward incursions of warm air. In U.S. Northeast, collision of cold Arctic air with moisture-laden air over warmed Atlantic can cause extreme snowfall. What we know: Ongoing impacts on people and ecosystems Growing harm: Coral bleaching “As of February 2017, the ongoing global coral bleaching event continues to be the longest and most widespread ever recorded.” https://coralreefwatch.noaa.gov/satellite/analyses_guidance/global_coral_bleaching_2014-17_status.php Jarvis Reef, South Pacific (courtesy WHOI) What we know: Ongoing impacts on people and ecosystems
  19. 19. 2/15/2018 19 Growing harm: Ocean acidification The link is that dissolved CO2 forms weak carbonic acid (H2O + CO2  H2CO3), lowering the pH. About 1/3 of CO2 added to atmosphere is quickly taken up by the surface layer of the oceans (roughly, the top 80 meters). World Bank / Potsdam Institute Nov 2012 What we know: Ongoing impacts on people and ecosystems Growing harm: Death of coral reefs in Florida Keys NASA Aqua satellite imagery. Washington Post, 26 June 2017 Florida’s coral reefs are being devastated by multiple stresses, of which warming water and acidification are the most important. Less than 10% of the reef system is now covered by living coral. (Red circles show percentage declines since 1996.) What we know: Ongoing impacts on people and ecosystems
  20. 20. 2/15/2018 20 Growing harm: Thawing/subsiding permafrost Norwegian Polar Institute, 2009 Russia Fairbanks, AK What we know: Ongoing impacts on people and ecosystems EPA 2016 Growing harm: Rising sea  coastal inundation What We Know: Ongoing impacts on people and ecosystems
  21. 21. 2/15/2018 21 Growing harm: rising sea  coastal erosion What We Know: Ongoing impacts on people and ecosystems Cape Cod Times Cape Cod loses 33 acres per year to inundation and coastal erosion. Growing harm: Stronger tropical storms • 10/12: Sandy, largest ever in Atlantic • 11/13: Haiyan, strongest in N Pacific • 10/15: Patricia, strongest worldwide • 10/15: Chapala, strongest to strike Yemen • 02/16: Winston, strongest in S Pacific • 04/16: Fantala, strongest in Indian Ocean • 10/17: Ophelia, strongest in E Atlantic Sandy Winston What We Know: Ongoing impacts on people and ecosystems
  22. 22. 2/15/2018 22 Growing harm: Pest outbreaks USGCRP 2009 Pine bark beetles, with a longer breeding season courtesy of warming, devastate trees weakened by heat & drought in California, Colorado, Alaska… What We Know: Ongoing impacts on people and ecosystems Growing harm: Increased vector-borne disease What We Know: The ongoing impacts on people and ecosystems Climate Nexus
  23. 23. 2/15/2018 23 Growing harm: Impacts on valued species Shifting patterns in Pacific climate, West Coast salmon survival rates, and increased volatility in ecosystem services What We Know: The ongoing impacts on people and ecosystems Valued species: Walruses impacted by shrinking sea ice Courtesy Fran Ulmer Along with whales, seals, polar bears Gary Braasch What We Know: The ongoing impacts on people and ecosystems
  24. 24. 2/15/2018 24 What’s Coming: The future of climate change and its impacts “Prediction is difficult…especially about the future.” attributed to Yogi Berra and Neils Bohr What’s coming depends on future emissions IPCC 2013 Target of ∆T ≤ 2ºC IPCC Scenarios Last time T was 2ºC above 1900 level was 130,000 yr BP, with sea level 4-6 m higher than today. Last time T was 3ºC above 1900 level was ~30 million yr BP, with sea level 20-30 m higher than today. Note: Shaded bands denote 1 standard deviation from mean in ensembles of model runs Scientific best estimates under specified future emissions Global average T continues to increase under all plausible scenarios. Momentum in the climate sys- tem means T continues to go up even after at mospheric con- ditions stabilize. And sea level continues to go up even after T stabilizes.
  25. 25. 2/15/2018 25 Under high emissions: heat extremes multiply Scientific best estimates under specified future emissions 38. Under high emissions: SW Europe roasts observations HadCM3 Medium-High (SRES A2) 2003 2040s 2060s Temperatureanomaly(wrt1961-90)°C July-August T in southwestern Europe The 2003 heatwave killed 35,000-70,000 people in France, Spain, & Italy. Summers as hot as 2003 will likely be the norm by the 2040s and will be considered unusually cool by the 2060s. Scientific best estimates under specified future emissions
  26. 26. 2/15/2018 26 Under high emissions: much of USA roasts, too Scientific best estimates under specified future emissions National Academies, Stabilization Targets, 2010 These declines are without taking into account any increase in major droughts. Scientific best estimates under specified future emissions
  27. 27. 2/15/2018 27 Frequency of 4-6 month duration droughts (events per 30 years) Under high emissions: Drought frequency soars 2070-2099, IPCC A2 scenario 1961-1990 Results shown are the mean of 8 global climate models. Drought defined as soil moisture below historical 10th percentile value for that calendar month. Source: Sheffield and Wood 2008 Climate Dynamics (2008) 31:79–105 DOI 10.1007/s00382-007-0340-z events per 30 years Scientific best estimates under specified future emissions Percentages shown are increases in median annual area burned, referenced to 1950-2003 averages, for a 1°C rise in global average temperature. National Academies, Stabilization Targets, 2010 Even a 2C increase (low emissions) portends a large worsening of wildfires Scientific best estimates under specified future emissions
  28. 28. 2/15/2018 28 Increased storminess in all scenarios Scientific best estimates under specified future emissions Bhatia and Vechhi, Princeton U, 5 April 2017 Princeton hurricane model projects increase in land- falling Cat 3-5 hurricanes in the Northeast These findings are for the IPCC’s RCP4.5 emissions scenario—a mid-range case, not the worst! Scientific best estimates under specified future emissions
  29. 29. 2/15/2018 29 Sea level likely to rise another 0.5-2 m by 2100 NOAA OAR CPO-1, December 2012 Sea-level rise continues for many centuries after 2100 in all scenarios, ultimately reaching 2 meters or more per degree of global avg warming. Scientific best estimates under specified future emissions Sea level: Flooded area with 1 meter rise Scientific best estimates under specified future emissions
  30. 30. 2/15/2018 30 Acidification: Continued drop in ocean pH in all scenarios, with significant impacts on marine life Steffen et al., 2004 Increased acidity lowers the availability of CaCO3 to organisms that use it for forming their shells & skeletons, including corals. Adverse effects are already being observed. Coral reefs could be dead or in peril over most of their range by mid to late 21st century. 1870, 280 ppm 2003, 375 ppm 2065, 515 ppm Scientific best estimates under specified future emissions Some of the worst possibilities • Rapid CH4 and CO2 release from thawing permafrost & warming Arctic sediments, accelerating all climate-related impacts (WHRC focus) • Massive drying & fires in the (formerly) moist tropics, with huge damage to local peoples & biodiversity (WHRC focus) • Greatly accelerated sea-level rise from rapid disintegration of Greenland and Antarctic ice sheets • Ocean fisheries crash caused by combination of warming, acidification, oxygen depletion, toxics, overfishing… • Collapse of the Atlantic Meridional Overturning Circu- lation, shutting down the Gulf Stream All of these become more likely as T rises above 1.5C. What else could happen (probability/timing/magnitude not well quantified)
  31. 31. 2/15/2018 31 What We Should Do “If you don’t change direction, you’ll end up where you’re heading.” Lao Tzu There’s a big difference in expected harm depending on the action society takes IPCC WGII, 2014 The high-emissions scenario, with global avg T increase of 5C or more, would entail catastrophic impacts. What We Can Do
  32. 32. 2/15/2018 32 What We Should Do So hiding our heads in the sand is not smart Society’s options There are only three: • Mitigation, meaning measures to reduce the pace & magnitude of the changes in global climate being caused by human activities. • Adaptation, meaning measures to reduce the adverse impacts on human well-being resulting from the changes in climate that do occur. • Suffering the adverse impacts and societal disruption that are not avoided by either mitigation or adaptation. What We Should Do
  33. 33. 2/15/2018 33 Concerning the three options… • We’re already doing some of each. • What’s up for grabs is the future mix. • Minimizing the amount of suffering in that mix can only be achieved by doing a lot of mitigation and a lot of adaptation. – Mitigation alone won’t work because climate change is already occurring & can’t be stopped quickly. – Adaptation alone won’t work because adaptation gets costlier & less effective as climate change grows. – We need enough mitigation to avoid the unmanage- able, enough adaptation to manage the unavoidable. What We Should Do Mitigation possibilities include… (CERTAINLY) • Reduce emissions of greenhouse gases & soot from the energy sector • Reduce deforestation; increase reforestation & afforestation • Modify agricultural practices to reduce emissions of greenhouse gases & build up soil carbon (CONCEIVABLY) • “Scrub” greenhouse gases from the atmosphere technologically • “Geo-engineering” to create cooling effects offsetting greenhouse heating What We Should Do
  34. 34. 2/15/2018 34 How much mitigation, how soon? • Limiting ∆Tavg to ≤2ºC is now considered by many the most prudent target that still may be attainable. – EU embraced this target in 2002, G-8 & G-20 in 2009 – Paris added 1.5C as “aspirational goal” in 2015 • To have a >50% chance of staying below 2ºC: – atmospheric concentration of heat-trapping substances must stabilize at around 450 ppm CO2 equivalent (CO2e); – to get there, developed-country emissions needed to peak around 2015 and decline rapidly thereafter, and – developing-country emissions must peak no later than 2025 and decline rapidly thereafter. What We Should Do Adequate mitigation will require addressing most heat-trapping substances across most emitting sectors in most countries. Mitigation: Everybody must get on board Distribution of CO2 emissions among nations CO2 and non-CO2 GHG Sectoral sources of global GHG emissions What We Should Do
  35. 35. 2/15/2018 35 Is the needed mitigation affordable? • Detailed analysis by the McKinsey group indicates that a carbon tax increasing over time to $70 per ton of CO2e by 2030 (in 2015 dollars) would put the world on a 2C trajectory.  The total tax bill (reaching $2T per year in 2030) is not the cost, because the average cost to reduce emissions would be much less than $70 per ton. Gov’ts could spend most of it in other ways.  GWP in 2030 at 2.5%/yr growth between now and then would be $170 trillion, so even the $2 trillion figure would be ~1%. • World now spends 2% of GWP on defense; USA spends 3.3% of GDP on defense, 1.7% on env protection. Such costs are not “losses”, just choices about resource allocation. • Most economic models find aggressive mitigation reduces GWP by 2-3% of GWP in 2100, but they underestimate innovation. Far less affordable would be costs of unmitigated climate change. What We Should Do Adaptation possibilities include… • Developing heat-, drought-, and salt-resistant crop varieties • Strengthening public-health & environmental- engineering defenses against tropical diseases • Preserving & enhancing “green infrastructure” (ecosystem features that protect against extremes) • Preparing hospitals & transportation systems for heat waves, power outages, and high water. • Building dikes and storm-surge barriers against sea-level rise • Avoiding further development on flood plains & near sea level Many are “win-win”: They’d make sense in any case. What We Should Do
  36. 36. 2/15/2018 36 The need for (& current lack of) Federal leadership THE OBAMA ADMINISTRATION… • Boosted climate research & monitoring; invested in clean- energy R&D & incentives; promulgated aggressive efficiency standards; promoted climate-change adaptation • Launched the “Climate Action Plan” with further mitigation, adaptation, & international initiatives; reached agreement with China leading to Paris accords with 195 countries THE TRUMP ADMINISTRATION… • Put climate contrarians in charge at OMB, EPA, DOI, & DOE while leaving most key science positions unfilled; proposed deep budget cuts in climate science & clean energy R&D • Cancelled Obama’s Climate Action Plan & Executive Orders on adaptation; withdrew from Paris accords What We Should Do What states, communities, businesses, scientists, philanthropists, & opinion leaders should do • States, communities, & businesses (and universities!) should devise and implement their own mitigation & adaptation plans (as many already have been doing). • Scientists should continue to… – monitor & analyze climate change and improve projections; – explain to every available audience what we know, how we know it, how it affects that audience, how we can fix it. • Philanthropists should seek to fill gaps in climate research & education created by Federal government’s cutbacks. • Opinion leaders should refine their ability to explain climate change impacts & remedies and rebut contrarian errors. • All should let Congress & President Trump know that abdicating U.S. government leadership on climate change is folly. What We Should Do
  37. 37. 2/15/2018 37 What else individuals should do REDUCE YOUR OWN CARBON FOOTPRINT • Get an energy audit of your home & shrink its energy waste • Replace incandescent (and even fluorescent) lights with LEDs • Put solar cells on your roof • Walk, bike, or take public transportation rather than driving • For needed driving, get a hybrid, all-electric, or other high- fuel-economy car • Recycle, and, better yet, re-use (shopping bags, utensils, drink containers…) • Eat less meat • Invest in companies that are taking action on climate (and disinvest in those that aren’t) • And, for the biggest impact available to young people, have one fewer kid! What We Should Do “Trend is not destiny.” Rene Dubos Thank you!

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