Global Warming So What? . April 2014 .
Pay ranchers and farmers to move Carbon neutral is no longer enough. carbon from the air back into soils. Why? We already have too much CO2 in the air. Warming could well triple, vanishing Arctic sea ice (about 1°F warming), phasing out coal’s sulfur emissions (ditto)& warming Earth enough so energy out = in (ditto). Too much heat can cut crop yields in half. Don’t let our food supply dry up. Give every American a $300 carbon tax credit Pay for it with a 3¢ / lb carbon tax,. Replace CO2regs. even without more CO2. Blame each year. rising 5% / year. Tax bad stuff (CO2). Tax income (good) less.
WATER FOOD . Rainfall becomes more variable. Planet-wide, we get a little more rain. Around the Arctic gets lots more, mid-latitudes (20-40°) less rain.. Yet in any one place, we get more hours and days without rain. In other words, we get more downpours and floods, yet also longer, drier, hotter droughts.
Droughts Worsen . Evaporation increases. Droughts Worsen.
• 3-Year Moving Average US Warming Graph . +5.8°F / century trend +12.1°F / century -2.4°F / century Consider Salina, Kansas, in the heart of wheat country, breadbasket of the world. At this rate, by 2100 summer in Salina would be like Dallas now. At the 12.1°F rate, by 2100 summer in Salina would be like Las Vegas now.
Greenhouse Effect Dark Earth absorbs sunlight. Earth warms up and radiates heat. Greenhouse gases in the air (GHGs) intercept some outgoing radiation and re-radiate it back down. This warms Earth more. More GHGs = warmer still. Light surfaces reflect sunlight. Those surfaces don’t warm Earth much. Changing a light surface (ice) to a dark one (water) warms Earth. Changing a dark surface (forest) to a lighter one (desert) cools Earth.
Greenhouse Gases • GHGs warm Earth by 32°C (58°F). Earth would average 0°F without them. • Water vapor (H2O) does 2/3 of this warming. As Earth warms up, evaporation increases H2O in the air. This amplifies warming from other GHGs a lot. • Carbon dioxide (CO2) does 52% of the rest. Almost all US CO2 comes from burning coal, oil & natural gas. Per unit of energy, coal emits 4 units of CO2, oil 3, natural gas 2. • Methane (CH4, natural gas) does 30% CH4 comes from wetlands, cows, leaky coal mines & gas wells, rice, landfills. • CFCs, nitrous oxide, and other gases do the rest. (10% indirectly via O3).
• CO2 Levels in the Air , Up 42% highest level in 15-20 million years Earth then was 5-11°F warmer. (35% Since 1880) Seas then were 80-130 feet higher. Annual Averages CO2 level as high 3.0-3.5 million years ago Earth then was 3-6°F warmer. Seas then were 65-120 feet higher. This means ice then was gone from almost all of Greenland, some of East Antarctica. most of West Antarctica, and 300 ppm (maximum between ice ages) CO2 levels now will warm Earth’s surface 5°F We face lag effects. So far, half the CO2 we’ve emitted has stayed in the air. The rest has gone into carbon sinks. , not just the 2°F seen to date. Current CO2 levels are already too high for us. - into oceans, soils, trees, rocks. CO2 Levels in Air
• • Ocean Heat Content . Of the net energy absorbed by Earth from the Sun, ~84% went to heat the oceans. 7% melted ice, 5% heated soil, rocks & trees, while only 4% heated the air. Levitus, 2005 1967-1990 0.4x 1022 Joules / year I 1991-20050.7x 1022 Joules / yr 1022 Joules = 100 years of US energy use, at 2000-13 rate 2006-2013 1.2x 1022 Joules / yr = 20 xhuman use acceleration Heat Content (1022 Joules) By now, the oceans gain more heat ievery 2 years than ALL the energy we’ve ever used. IMMENSE heat gain From 2007 to now, ocean heat gain has switched to mostly (70%) below 700 meters deep. Since 2007, ~90% goes to heat oceans, less to air and others. We notice air heating slower.
Sun vs Temp . ∆ °C Watts / m2 - World Radiation Center - NASA Solar Irradiance at Earth Orbit, Annual Average Global Air Temperature, Land Surface, 3-Year Moving Average In 2007, solar output was the lowest yet recorded (in 28 years), but Earth’s air temperatures (land surface) were the highest yet recorded.
Sulfates &Cooling Dark sulfates in the air block sunlight. Sulfates make haze More sulfates= cloudier = cooler. Most sulfates come from burning coal, SO2 goes up the smokestacks. GHGs stay in the air many years, GHG levels keep rising. Sulfates now offset 30-40% of GHG warming: As we stop sending up SO2, That cools Earth. & become cloud condensation nuclei. some from volcanoes. It changes to SO4 (sulfate) up in the air. sulfates usually for days. Sulfate levels don’t. 0.5-0.7°C. warming will catch up.
• ∆°C sulfates still 3x 1880 levels NASA GISS - Earth’s 7,000 weather stations - adjusted for urban heat island effects Brown . cloud. grows over .. China, India. . warmingunmasked Sulfates fall 27%. cool Sulfate Cooling Un-Smooths GHG Warming Pinatubo erupts Coal-Fired Power Plants Sulfates fall 13%. Sulfates up 46%. Sulfates up 52% (61/40). cool Sulfatesup 110%. El Chichón erupts major cooling cool warming unmasked cool Katmai, Colima erupt Santa Maria, Soufriere, Pelee erupt USSO2 cuts start. Agung erupts Krakatoa erupts warming unmasked cool Great Depression cool less SO2 up the stacks cool cool Cooling offsets GHG warming. Cooling offsets GHG warming. Cooling limits GHG warming. 40 89 116 118 61 77 162 1880 2000 Sulfate Levels in Greenland Ice milligrams of Sulfate per Ton of Ice (Intergovernmental Panel on Climate Change, 2002)
Earth Is Heating Up. Earth now absorbs 0.25%more energy than it emits – a 300 millionMWheat gain 300 million MW This absorption has been accelerating, from near zero in 1960. Earth will warm another 0.6°C . just so it emits enough heat to balance absorption. Airat the land surface is 1.0°Cwarmer than a century ago. Half that warming happened in the last 33 years. • Airat the sea surface is 0.8°C warmerthan a century ago. 84-90% of the energy Earth absorbs heats the oceans. If it all went to melt Greenland ice, the ice would vanish in 70 years.. The oceans have gained ~10 x moreheat in 40years than ALL the energyhumans have EVER used. ~ means “approximately, roughly, is about equal to” 1°C = 1.8°F. One MW can power several hundred US homes. (±75 million MW) = 70 xglobalelectric supply = 20 x human energy use. , so far,
Tipping Points • Report to US & British Legislators - January 2006 What would make climate change accelerate, so natural forces defeat our efforts to slow it? • Disappearance of sea ice means more heat is absorbed by the water below. • Carbon sinks fade & fail in oceans & forests. Some become carbon sources. 3 Methane release from permafrost revs up warming in a vicious circle.
More Heat - So? Water Hurricanes convert ocean heat to powerful winds & heavy rains. Intense hurricanes are becoming more common. Higherhurricane energy closely tracks sea surface warming. With more carbon, oceans have grown more acidic. So, forming shells is more difficult. They dissolve easier. Warmer water holds less dissolved oxygen. Fish & mollusks suffer. Jellyfish prosper. Sea surfaces warmed 0.15°C over 1997-2004, so planktonabsorbed 7% less CO2. Warming was far strongest in the North Atlantic. CO2 uptake therefell by half. Ocean phytoplankton levels may be down 40% since the 1950s. Phytoplankton supply half of Earth’s oxygen.
Reservoirs in the Sky Most mountain glaciers dwindle ever faster: in the Alps, Andes, Rockies, east & central Himalayas. When Himalayan glaciers vanish, so could the Ganges River (& others) in the dry season. When Andes glaciers vanish, so does most of the water supply for Lima and La Paz. Mountain snows melt earlier. CA’s San Joaquin River (Central Valley, US “salad bowl”) could dry up by July in most years. The Colorado River’s recent 10-year drought was the worst since white men came.
Earth’s Thermostat. Minimum ice area fell 37% in 34 years, Arctic Ocean ice could vanish by fall in 5 years Greenland’s netice-melt rate rose 5xover the past 15 years. Its yearly net melt-water is already 1/2 of US water use. Antarctica is losing 1/3 that much, but has 9 x as much.. So, sea level will likely rise 1-7 feet by 2100 . Thawing Arctic permafrost has 5 xMORE carbon than ALL our fossil fuelsemitted. Already, Arctic permafrost emits ~ as much carbon as all US vehicles. Thawing permafrost can add ~100ppm of CO2 to the air by 2100, 280 more by 2300. Seabed methane hydratesand stores under Antarctic ice hold much more carbon. Arctic Ocean ice is shrinking fast. As the ice recedes, Earth absorbs more heat. It will warm more, even without more CO2. PIOMAS Wipneus U of Bremen The ice got thinner too. , 53% in the last 10. while volume fell 72% & be gone all summer in 12. & far more afterward.
Hot &Dry From 1979 to 2005, the tropics spread. . Sub-tropic arid belts grew ~140 miles toward the poles, . a century ahead of schedule. . That means our jet stream moves north more often. In turn,the US gets hot weather more often. 2011-12 was America’s hottest on record. . Over September 2011 - August 2012, relative to local norms, 33 states were drier than the wettest state (WA) was wet. In 2012,44 of 48 states were drier than normal. Severedrought covered a record 35-46% of the US . Drought reduced the corn crop by a quarter. . The soybean crop was also hit hard. The Mississippi River neared a record low. Lake Michigan hit one. By 2003, forestfires burned 6 x as much area / year as before 1986. Pine bark beetles ravage Rocky Mtn forests.. What Else? , for 39 weeks. Record prices followed. US fires to double by 2050.
Notable Recent Droughts . When I was young, the leading wheat producers were the US Great Plains, Russia’s steppes, Canada, Australia, and Argentina’s Pampas. Notable Recent Droughts. When WhereHow Bad 2003 France, W Europe record heat 2003-10 Australia worstin millennia. 2005 Amazon Basin once a century. 2007 Atlanta, US SE once a century 2007 Europe: Balkans record heat, Greek fires, 2007-9 California record low rain in L.A. 2008-9 Argentina worst in half a century 2008-11 north China ~worst in 2 centuries. 2009 India monsoon season driest since 1972 2010 Russia record heat, forest fires. 2011 Texas, Oklahoma recordheat & drought 2012 US: SW, MW, SE most widespread in 78 years; record heat “Once a century” droughts are now happening once a decade. #3 now hotter in 2012 , 20-70K die. Record heat in 2013. Worse in 2010. Since 1979, its dry season grew longer by 1 week per decade. hundreds die. CA worse in 2013. China now #1 in wheat. #2 in wheat Wheat prices up 75%. 15K die.
Groundwater . Over 1994-2007, desertsgrew from 18 to 27% of China’s area... Yearly net US groundwater withdrawals for irrigation grew since 1950, . from 1.6 to 4.4% of US water use now. . 1/5 of wheat is irrigated in the US, 3/5 in India, 4/5 in China. . Central CA loses enough to irrigation yearly to fill Lake Erie in 100 years. . Groundwater loss from India’s Ganges Basin would fill Lake Erie in 10. . With more evaporation & irrigation, many water tables fall. Worldwide, irrigation wells chase water ever deeper.. Many wells in China’s wheat belt must go down 1,000 feet for water. . Since 1985, halfthe lakes in Qinghai province (China) vanished. . 92% in Hebei(around Beijing), Inland seas and lakes dry up& vanish . the Aral Sea, Lake Chad (Darfur), Lake Eyre, Sea ofGalilee. . More riversfailtoreach the sea:. Water No Is That All? So, the Ogallala Aquifer dwindles. 3-20 feet a year. Water prices rise. as water tables dropped below lake beds. , for example: Yellow,Colorado, Indus, Rio Grande, etc.
• Droughts Are Spreading Already. Switch from what could happen to what has happened already. combined effect 30% = 16 million square miles 10 million more square miles Compare 2002 to 1979. 11% of the area during 1951-80: once per 9 years Area whererain is scarce increased by quite a bit: 3-6 million square miles. Evaporationincreased, by a lot since 1987. Compare 30% actualsevere drought area in 2002 (11% of the time during 1951-80) to 27% projected for 2000-2004 in previous slide. from Fig. 9 in Aiguo Dai, Kevin E. Trenberth, Taotao Qian [NCAR], "A Global Dataset of Palmer Drought Severity Index for 1870-2002: Relationship with Soil Moisture and Effects of Surface Warming,”Journal of Hydrometeorology, December 2004, 1117-1130 Droughts spread, as projectedor faster. Evaporation at work Earth’s area in severe droughthastripledsince 1979. Over 23 years, the area with severe drought grew by the size of North America.
as projected SUMMARY or faster. Severedroughthas arrived, Severe droughtnow afflicts an area the size of Asia. So, farmers mine groundwater ever faster for irrigation. From 1979 to 2002 (+0.5°C) . 1) The area where rain is scarce increased by the size of the United States. Add in more evaporation.. 2) The area with severe drought grew by the size of North America. 3) The area suffering severe drought tripled. 4)The similarly wet area shrankby the size of India.
Turning Wheat into Cactus . In 2005-6, scientists calculated how climate would change for 9 Northeast and 6 Great Lakes states in 2 scenarios: #1 - a transition away from fossil fuels, or #2 - continued heavy reliance on them (business as usual emissions). By 2085, averaged across 15 states, the climate change would be like moving 330 miles to the SSW (coal & oil use dwindle), or moving 650 miles to the SSW (heavy coal & oil use). Consider central Kansas, heart of wheat country. 330 miles to the SSW lies the area from Amarillo to Oklahoma City. 650 miles to the SSW lies the area around Alpine & Ft. Stockton, TX. 2 people / square mile. Cactus grows there. Mesquite & sagebrush too. No wheat
• ExtremeDroughtCanClobberEarth • In 1989, NASA climate models showed, as CO2 levels rise and Earth warms up, droughts would spread and intensify. • “Once-per-9-year” droughts would cover 27% of Earth by 2002. • With business as usual emissions, by 2059 CO2 levels would double pre-industrial levels. • As a result, Earth would warm 4.2°C [7.5°F] from 1880 levels. Rain would increase 14%. • Despite the added rain, increased evaporation would bring extreme “once-a-century”drought to 45% of Earth, & rising. WET DRY 0 1 5 16 36 36 16 5 1 0 % Occurrence in Control Run Fig. 1d in David Rind, R. Goldberg, James Hansen, Cynthia Rosenzweig, R. Ruedy, “Potential Evapotranspiration and the Likelihood of Future Droughts,”Journal of Geophysical Research, Vol. 95, No. D7, 6/20/1990, 9983-10004. .
What Drives Drought? The water-holding capacity of air rises exponentially with temperature. Air 4°C warmer holds 33% more moisture at the same relative humidity. . more moisture in the air does not equal more clouds. To maintain soil moisture, ~10% more rain is required to offset each 1°C warming. Warmth draws more water UP (evaporation), so less goes DOWN (into soils) or SIDEways (into streams). Morewater isstoredin theair,lessinsoils. Not all the water that goes up comes back down. Thus,
Droughts - Why Worry? . Droughts - Why Worry? 2059 - 2 x CO2 (Business as Usual Emissions) . More moisture in the air, Average US stream flows decline 30%, Tree biomass in the eastern US falls by up to 40%. More dry climate vegetation: The vegetation changes mean • Biological Net Primary Productivity falls 30-70%. SWITCH from PROJECTIONS to ACTUALS. . • Satellites show browning of the Earth began in 1994. . Rind et al., 1990 but 15-27% less in the soil. despite 14% more rain. savannas,prairies, deserts Fung 2005 Zhao 2010
Crop Yields Fall. Rind et al., 1990 - 3 of the big 4 crops (rice is the 4th) United States: 2059 Projections - doubled CO2 - Business as Usual • Great Lakes, Southeast, southern Great Plains • Corn, Wheat, Soybeans 2 Climate Models (Scenarios) . • NASA GISS Results Goddard Institute for Space Studies • Yieldsfall30%, averaged across regions & crops. • NOAA GFDL Results Geophysical Fluid Dynamics Lab • Yieldsfall50%, averaged across regions & crops. CO2 fertilization not included . So things won’t be this bad, especially this soon. Temperature effects of doubled CO2 will keep growing - eventually to 4.2° or 4.5°C - but over many decades, even after 2100. CO2fertilization boosts yields 6-30% or more in experiments, where water and other nutrients are well supplied, and weeds and pests are controlled. That won’t happen as well in many fields. Groundwater and snowmelt for irrigation grow scarcer in many areas. Other factors (esp. nitrogen) soon kick in to limit growth, so CO2 fertilization will falter. (based on 4.2°C warmer, 14% more rain) (based on ~ 4.5°C warmer, 5% less rain)
Photosynthesis, Warming & CO2 . Plants evaporate (transpire) water in order to [like blood] get it up to leaves, where H2O & CO2 form carbohydrates, pull other soil nutrients up from the roots to the leaves, and [like sweat] (3) cool leaves, so photosynthesis continues & proteins aren’t damaged. When water is scarce, fewer nutrients (nitrogen, phosphorus, etc.) get up to leaves. So, with more CO2, leaves make more carbohydrates, but fewer proteins.
Warming & Falling Yields . For wheat, corn & rice, photosynthesis in leaves slows above 35°C (95°F) and stops above 40°C (104°F). Warming(above 35° or 40°C) hurts warm, tropical areasharder& sooner. Over 1992-2003, warming above the norm cut rice yields by 10+% / °C. Over 1982-98, warming in 618+ US counties cut corn & soybean yields ~17% / °C. With more CO2, 2°C warming cut yields 8-38% for irrigated wheat in India. Warmer nights since 1979 cut rice yield growth 10%± in 6 Asian nations. Warming since 1980 cut wheat yield growth 5.5%, corn 3.8%.
Heat Spikes Devastate Crop Yields Heat Spikes Devastate Crop Yields Schlenker & Roberts 2009 . Based on 55 years of crop data from most US counties, and holding current growing regions fixed, average yields for corn and soybeans could plunge 37-46%by 2100 with the slowest warming and plummet 75-82%with quicker warming. Why? Corn and soybean yields rise with warming up to 29-30°C, but fall more steeply with higher temperatures. Heat spikes on individual days haveBIG impacts. More rain can lessen losses. Plants transpire more water to cool off. Growing other crops, or growing crops farther north, can help too.
World Grain Production . 80% of human food comes from grains. World grain production rose little from 1992 to 2006. Production per capita fell from 343 kilograms in 1985 to 306 in 2006. • UN Food & Agriculture Organization Worldwatch Institute 2006
World Grain Stocks . Any future food production increases will occur away from the tropics. In the tropics, food production will fall. Soil erosion continues. Water to irrigate crops will grow scarcer, as glaciers and snowpacks vanish, water tablesfall, and rainfall becomes more variable. Satellites show that, since1994, hotdrysummersoutweighwarm, wet springs. A world that was turning greener is now turning browner. Grainstocks (below) are at low levels. FAO: Crop Prospects and Food Situation
• Crop yields plateaued . Million Metric Tonnes harvest by nation in 2011 (right column) are used to calculate weights. Weighted average world grain yields per acre plateaued over 2008-12. This is consistent with spikes in food prices, and with forecasts of falling crop yields.
Food Price Index . Poor people could not afford to buy enough food in 2007-8. . Malnutrition & starvation rose. Food riots toppled governments in 2011. and 2010. With food stocks at low levels, food prices rose steeply in 2007-8 2002-04 = 100 UN, Food & Agriculture Organization: World Food Situation / FAO News Ditto 2010-11.
• Estimated Impact of +3°C on Crop Yields by 2050 for wheat, rice, maize, soybean & 7 other crops One of many studies, more pessimistic than average. average of 3 emission scenarios, across 5 global climate models, no CO2 fertilization from Chapter 3 in World Development Report 2010: Development and Climate Change. by World Bank, Müller, C., A. Bondeau, A. Popp, K. Waha, and M. Fader. 2009. “Climate Change Impacts on Agricultural Yields.” Potsdam Institute for Climate Impact Research citing
• Deserts Are Already Spreading. 75 60 45 30 15 0 -15 -30 -45 -60 50 Year Trend in Palmer Drought Severity Index, 1950-2002 The Sahara Desert is spreading south, into Darfur & the Sahel. . The Gobi Desert is spreading into northeast China. More sandstorms visit Beijing. Retreating glaciers moisten the soil in Tibet.. -180 -120 -60 0 60 120 180 Fig. 7 in Dai, Trenberth & Qian, Journal of Hydrometeorology, Dec. 2004 -6.0-4.0-2.0 0.0 +2.0 +4.0 +6.0 More negative is drier. More positive is wetter. See Spain, Italy, Greece. The USA lucked out till 2007.
2°C has become unavoidable. 2° vs 4° Warming . 1.0°C warming is here. Holding warming to 2°C, not 4°, prevents these losses: 3/4 of Gross World Product $42 Trillion ~ 3/4 of GWP 1/5 of the World’s Food . 2/3 of the Amazon Rainforest 1/8 of the world’soxygensupply Gulf Stream + West Antarctic Icecap . Florida & Louisiana, central CA, Long Island, Cape Cod 1/2 of all Species . 2°C warming is manageable. Details to follow: first 2°C, next 3°, then 4°, finally 5°C. - Norfolk area, much of 4°Cthreatens civilization itself.
* includesCH4, SO4, soot,O3, N2O, CFCs 2°C Warming - 450 ppm CO2e*.. Many more major floods (Waxman-Markeybill or Kerry-Boxerbill in Congress) . Stern Review, British government, Oct. 2006 . (a report by dozens of scientists, headed by the World Bank’s chief economist) . selected effects - unavoidable damages. • Hurricane costs double. • Major heat waves are common. • Droughts intensify. • Civil wars & border wars over water increase: • Crop yieldsrisenowhere, fall in the tropics. • Greenland icecap collapsebecomes irreversible. • The Ocean begins its invasion of Bangladesh. Forestfires worsen. Deserts spread. more Darfur’s.
3°C Warming - 550 ppm CO2e Stern Review + (McCain-Lieberman bill, watered down) additional damages – maybe avoidable • Droughts & hurricanes get much worse. • Hydropower and irrigation decline. • Crop yieldsfallsubstantiallyin many areas. • More water wars & failed states. • 2/3ofAmazonrainforestmayturntosavanna,desertscrub. • Tropical diseases (malaria, etc.) spread farther & faster. • 15-50%of species face extinction. Water is scarce. Terrorists multiply.
.4°C Warming - 650 ppm CO2e.. Stern Review (double pre-industrial levels) (Bush proposal) further damages - avoidable • Water shortages afflict almost all people. • Crop yieldsfallinALLregions,by1/3inmany. • Entire regions ceaseagriculture altogether. • Water wars, refugee crises, & terrorism become intense. • Methane releasefrom permafrost accelerates more. • The Gulf Stream may stop, monsoons often fail. • West Antarctic ice sheet collapse speeds up.
5°C Warming . 5°C Warming - 750 ppm CO2e (Business as Usual Emissions) . Deserts GROW by 2 x the size of the US. World food falls by 1/3 to 1/2. Human population falls . to match the reduced food supply. Other species fare worse. a lot,
UN Chief on Climate Change . Some scientists are saying publicly that if humanity goes on with business as usual, climate change could lead to the collapse of civilization, even in the lifetime of today's children. United Nations Secretary General Ban Ki-Moon said “I think that is a correct assessment.” He added carefully “If we take action today, it may not be too late.” September 24, 2007
Costs ―––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––-–––––----––––––––––––––––– Costs ofInaction: including $120 billion ($400 / American) in the US for 2012 . Already 0.5 million / year die worldwide,. $74 Trillion . This exceeds GWP. . a HUGE hiddenTAX:$50,000 / American $85 / Ton of CO2 ―––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––------–––––––––––––––––––––– Costs ofAction: Spend 1% of GWP ($150 billion by US), each year, ± 2%. Damages fall to $25 - $30 / Ton of CO2. World Savings ~ $2.5 Trillion, net from each year’s spending. inflation-adjusted $, Business as Usual Stern Review DARA, Watkiss / Hope, now $695 Billion/Year (more than 1% of GWP), (almost 1% of US GNP). +4.5 million from coal sulfates. Costs GROWover time. : 2005-2200) (present value (2%/year discount rate) annualized: $1.5 Trillion / year $30-75 / year / American – CBO, EPA
Solutions Put way less carbon in the air. Take carbon out of the air, big time.
• CO2 Emission Paths to Stabilization . Stern Review 2006 CO2e (CO2 equivalent) includes warming from CO2 & other GHGs, less the cooling effect of sulfates. -32% Total Warming +3°C -67% -75% +2°C The paths assumeNOemissionsfrompermafrostor seabedmethanehydrates, nor lagged warming from vanishing sea ice & sulfates, nor warming so energy out = in. (397 CO2 + 362 other GHGs - 222 sulfates = 537). We already exceed 450 ppm CO2e for +2°C Holding eventual warming to 2°C may no longer be possible, unless we take lots of CO2 out of the air.
Take Carbon Outof the Air. Perennial grass roots add carbon to soil. with short rotation cattle grazing, like buffalo. Lots more rain soaks in. (1 oz C/sq ft) Cut CO280 ppm. , for $20-100/T. Speed up natural process10 x. Rebuild soil carbon even more, retain water. Algae bloom, suck CO2 from the air. even if fertilization works well. Oceans may be too small, soon carbon returns to air. Tiny critters eat them; Other problems will arise. 1 Rebuild rangelands. Speed up process 10-50 x Dung beetles move carbon underground. Absorb 1 T carbon (3.7 CO2)/acre/yr. 2 Farming, done right, can put 1.5 - 4.3 GT CO2 /yr in soil Organic farms add 0.5 T C (1.8 CO2)/acre/yr to soil. Rebuild soil organic matter: from 1-3% now, to 6-10% before farming. 3 Rocks have weathered for eons, taking 1 GT CO2 /yr from the air. Move CO2 into crushed rock (basalt, etc.) Spread around millions of 2-story towers with crushed rock. 4 Bury biochar shallow in soils. 5 Add iron filings to select ocean areas. Algae must suck 8 x as much carbon from the air as our food supply does, just to break even. Dead algae may not sink. Additional fertilizers (K, P, N, etc.) may be needed.
Take More Carbon Out of the Air. 6Plant more trees. - for lumber, paper, palm oil, soybeans, ranches, fuelwood. . Trees need water, but soils will have less. 7Maintain forest soils: Below-ground carbon ~ above-ground(20-45ºN). (Permafrost holds 3-7 x as much carbon / acre as tropical rainforest.) . 8 Add silicates during hydrolysis at sea surface. A Add Sulfates to the Stratosphere – to block sunlight. We’d need a hundred flights every day to the stratosphere by big cargo planes. They’d be only 1% of what we now put in the troposphere. But it would shift rain from one region to another, e.g., leaving east Africa dry. B Mirrors in Space – to block sunlight We’d need half a million square miles of mirrors now, twice the size of Texas. Add that much in 30 years, and again in 50. Even if the mirrors are as thin as Saran Wrap, we’d need dozens of space shuttle-sized cargo launches every day this century. C Create more clouds, or whiten them more. It’s a good idea, but deforestation continues Forest fires run wild. humus, roots, fungi, bacteria, leaf litter. Drought & fires hurt. Scrub CO2 from the air. Geo-Engineering Smoke & Mirrors don’t slow acid in ocean. Only $10 billion / year! They drift outward - solar sails!
• World CO2 Emissionsfrom Fossil Fuels32.6 Billion Tons in 2011 US DOE / EIA . . . In late 2009, Chinapledged tocutits CO2 intensity 40-45% by 2020, India 20-25%. Chinawind powergrewmore than coal. * Misc. = Korea, Indonesia, Thailand, Taiwan, Malaysia, Vietnam, Bangladesh, etc. In 2012, In 2013-4, 7 China mega-cities start carbon cap & trade.
CO2 Emissions by Nation, Year . CO2 Emissionsfrom Fossil Fuels (Billion Metric Tons) China Misc. Asia= . Korea, Indonesia, Thailand, Bangladesh, Taiwan, Philippines, Malaysia, Vietnam, etc. Mid-East & Central Asia In 1992, Ukraine etc. to Europe, Kazakhstan, etc. to Central Asia. Misc. Asia Other Asia Japan India US M-E & CA = Turkey to Pakistan & Kazakhstan Europe Other USSR Latin America Africa Canada Russia Oceania = Australia, NZ, etc.
America’s Low-Carbon Revolution Has Begun US DOE / EIA US DOE / EIA Net Imports US DOE / EIA US DOE / EIA