1 Geology 1001/1101 Sec 003 Chris Paola Class 14: the Anthropocene

2 Chapter 14 HUMAN IMPACT ON EARTH’S ENVIRONMENT

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5 What is burning? CH 4 + 2O 2  CO 2 + 2H 2 O + energy methane oxygen carbon dioxide water

6 Relative carbon emissions FuelKg CO 2 / KWhr Coal0.37 Gasoline0.27 Diesel0.24 Natural gas0.23

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8 1. Incoming solar radiation What is the “greenhouse effect”? KEY IDEAS: 1. Energy must balance: output = input 2. Higher surface temp  higher rate of energy radiation 2. Surface temp increases until energy balances GHG 3. GHG return some of the outgoing energy back to earth as infrared radiation 4. Higher surface temp required to balance extra input energy NO ATMOSPHERE, e.g. Moon WITH ATMOSPHERE, e.g. Earth

Jordan, The Essential Earth 1e © 2008 by W. H. Freeman and Company

Observed changes in GHG levels, 10 kyr

Jordan, The Essential Earth 1e © 2008 by W. H. Freeman and Company observed temperature w.r.t mean

Jordan, The Essential Earth 1e © 2008 by W. H. Freeman and Company

numerical model prediction

Jordan, The Essential Earth 1e © 2008 by W. H. Freeman and Company

25 GW: Points that (I think) both sides agree on CO 2 is a greenhouse gas The observed increase in CO 2 levels is anthropogenic The Earth’s climate has warmed over the past couple of decades

26 but… CO 2 is a greenhouse gas The observed increase in CO 2 levels are anthropogenic The Earth’s climate has warmed over the past couple of decades CO 2 is not the most effective greenhouse gas Other anthropogenic changes work against GW The Earth’s climate undergoes important natural cycles that are not well understood

27 Both sides now… By not acting, we will create an environmental catastrophe A new “green” economy could be beneficial There is strong scientific consensus about GW By acting in haste, we will create an economic catastrophe A warmer climate could be beneficial Science is not a democracy; dissenting voices are being suppressed

28 There is no way around the fact that this and other important decisions about the environment will have to be made with imperfect scientific understanding. What is the best way to do this?

29 What is the “Anthropocene”? Holocene: geologic epoch since last glacial advance Anthropocene: proposed current geologic epoch of strong human influence

30 the Anthropocene Energy, Climate change, and CO 2 Land use Geo-engineering

31 Geo-engineering UM Institute on the Environment Momentum 2010 Spring

32 Geo-engineering

33 Geo-engineering

34 Geo-engineering Could stimulating plankton with Fe speed up the biological pump? “Give me half a tanker of iron, and I’ll give you an ice age” – John Martin, former Director, Moss Landing Marine Lab

JMA Potential for Reducing CO 2 Emissions from Fossil Fuel Power Generation CO 2 Capture and Storage Mobil Source: IEA Greenhouse Gas R&D Program R&D Program CO 2 Consumption Storage Gas, Oil, Coal Injection into Depleted Oil/Gas Reservoirs Increased Reforestation

36 The human footprint

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38 The human footprint Land loss in coastal Louisiana associated with river diking & flood control

39 Natural vs agricultural erosion

40 Natural vs agricultural erosion

41 The total earth moved in the past 5000 yr would be sufficient to build a 4000-m- high mountain range, 40 km wide and 100 km long. If current rates of increase persist, we could double the length of our mountain range in the next 100 yr. The human footprint R. L. Hooke (2000) Geology 28:843

42 The human footprint Sanderson, E. W. et al. (2002) Bioscience, 52, 891

43 The human footprint Sanderson, E. W. et al. (2002) Bioscience, 52,

44 The human footprint Sanderson, E. W. et al. (2002) Bioscience, 52, 891

45 How far to the nearest road? Fraction of US land area that is: Less than 127 m (417 ft) = 20% Less than 382 m (1253 ft) = 50% More than 1000 m (0.6 mi) = 18% More than 5000 m (3.1 mi) = 3% Coterminous US, from Riitters, K. H., and J. D. Wickham (2003), Frontiers in Ecology and the Environment, 1,

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