1

Geology 1001/1101

Sec 003 Chris PaolaClass 14: the Anthropocene

2

Chapter 14

HUMAN IMPACT ON

EARTH’S ENVIRONMENT

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

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

5

What is burning?

CH4 + 2O2 CO2 + 2H2O + energy

methane oxygen carbon dioxide water

6

Relative carbon emissions

Fuel Kg CO2 / KWhr

Coal 0.37

Gasoline 0.27

Diesel 0.24

Natural gas 0.23

7

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

AT

MO

SP

HE

RE

, e.

g.

Mo

on

WIT

H A

TM

OS

PH

ER

E,

e.g

. E

arth

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

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

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

1995-2000 observed temperature w.r.t. 1940-1980 mean

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

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

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

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

2070-2100 numerical model prediction

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

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

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

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

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

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

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

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

25

GW: Points that (I think) both sides agree on

• CO2 is a greenhouse gas

• The observed increase in CO2 levels is anthropogenic

• The Earth’s climate has warmed over the past couple of decades

26

but…

• CO2 is a greenhouse gas

• The observed increase in CO2 levels are anthropogenic

• The Earth’s climate has warmed over the past couple of decades

• CO2 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 CO2

• 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

JMAJMA

Potential for Reducing CO2 Emissionsfrom Fossil Fuel Power Generation

COCO22 Capture and Storage Capture and Storage

MobilMobilSource: IEA Greenhouse Gas Source: IEA Greenhouse Gas R&D ProgramR&D Program

COCO22ConsumptionConsumption

COCO22

Storage

Storage

Gas, O

il,

Coal

Injection into Depleted Oil/Gas ReservoirsInjection into Depleted Oil/Gas Reservoirs

Increased ReforestationIncreased Reforestation

36

The human footprint

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

Current: 6,818,119,630

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, 891-904.

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, 125-129.

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

47