{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

12. Global Warming - Global Warming Intergovernmental Panel...

Info icon This preview shows pages 1–19. Sign up to view the full content.

View Full Document Right Arrow Icon
Global Warming
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
http://www.youtube.com/watch?v=jOjfxEejS2Y Intergovernmental Panel on Climate Change IPCC Report 2007 http://www.ipcc.ch/
Image of page 2
Global Warming vs. Climate Change A tendency for the global mean surface temperature to increase Do you “believe in” global warming? Focus on climate change
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Global Warming Public Opinion (US) 2006 ~70% feel global warming is happening ~70% thought global warming was responsible for more extreme weather events 2010 Decreased to ~50% Climate-gate, Himalaya error (IPCC)
Image of page 4
Global Warming Hidden meaning (realclimate.org) 1) whether greenhouse gases are accumulating? 2) whether the greenhouse effect is established science? 3) whether global warming has been observed? 4) whether future climate change is expected to be big enough to worry about?
Image of page 5

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Earth’s Natural Greenhouse Review Earth Ave. mean global temp = 15°C Blackbody temps = -18°C (moon ave. temp = -16°C) Earth’s natural greenhouse effect = 33°C warming Makes Earth Habitable
Image of page 6
Knowns Concentrations of GHG are increasing The source of this increase is human activity (burning fossil fuels) Physics behind the greenhouse effect Increased global temperatures More debatable Global temperatures are increasing That increase is caused by anthropogenic GHG Global Warming
Image of page 7

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
• H 2 O, CO 2 , CH 4 Sources? Earth’s Natural Greenhouse Gases
Image of page 8
Sources H 2 O Water vapor, evaporation – mostly from tropics CO 2 Volcanism, decay of organic matter, respiration CH 4 Seepage from natural sources: wetlands (anaerobic decay), methane hydrates Earth’s Natural Greenhouse Gases
Image of page 9

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Greenhouse Effect (review) Incoming radiation Short wave radiation (visible light) Outgoing radiation Long wave radiation (infrared) Short wave VIS Long wave IR
Image of page 10
Greenhouse Effect (review) IR not enough energy to break bonds- imparts vibrational and rotational energy to molecules more collisions increase in total energy of motion in all air molecules increased temperature of the atmosphere (ave. energy of the motion of molecules) radiates that heat to space and to earth
Image of page 11

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Increases energy of ALL molecules But energy is initially absorbed by the greenhouse gases Due to relationship between bond lengths within the gas molecule and IR wavelengths Atmosphere then re-emits energy to the earth and space Greenhouse Effect (review)
Image of page 12
Earth as a Black Body (S/4)(1- α ) Earth σ T T e = 255K = -18°C
Image of page 13

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Atmosphere Earth’s Greenhouse see KKC box pg 43 (45) (S/4)(1- α ) Earth σ T T s = 288K = 15°C
Image of page 14
Anthropogenic GH Gases CO 2 CH 4 CFC -11 CFC -12 N 2 O Atmospheric Conc. ppm ppb ppt ppt ppb Pre- industrial (1750-1800) 280 800 0 0 288 Present Day 353 379 1720 1774 280 251 484 538 310 319 Rate of change /yr 1.8 1.86 15 3 9.5 -2 17 .5 0.8 .7 Atm lifetime (yrs) 50- 200 12 45 100 114 (from IPCC 1990 and 2007) 2005 2005 1990 1990
Image of page 15

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
“Keeling” Curve KKC 1-2 2011 = 391ppmV
Image of page 16
Atmospheric CO 2 Deforestation IPCC 2001 Deforestation Data from: ice cores Keeling curve
Image of page 17

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Atmospheric CO 2 Emissions Total Fossil Fuels Deforestation
Image of page 18
Image of page 19
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}