Slides for GGR 314,
Global Warming
Chapter 3: The Carbon Cycle
Course taught by
Danny Harvey
Department of Geography
University of Toronto
Exhibit 3-1: The pre-industrial carbon cycle
Atmosphere 560
120
60
M
Biota
720
aR
60-M-R
100
100
Surface Water 560
Soil & Detritus 5400
R
50
40
Biota 3
(1-a)R 10
10
Net Flux = B
Deep Ocean 34,000
B
Exhibit 3-2: Collapsing vegetation and exposure of previously frozen
C-rich soils as permafrost warms
Source: http://www.globalcarbonproject.org/news/SoilOrganicPoolsinPermafrost.html
Exhibit 3-3: A carbon rich soil above permafrost (left) and ice wedges
in permafrost (left)
Source: http://www.globalcarbonproject.org/news/SoilOrganicPoolsinPermafrost.html
Exhibit 3-4: Diatoms, depicted below, have SiO2 (siliceous, made of
silica) skeletons
Source: Wikipedia, Open Source photo in article on plankton
Exhibit 3-5: Coccoliths (left) and foraminifera (right) have calcium
carbonate (calcareous) skeletons
Width of image: 5.5 mm
Source: Left, Wikipedia, Richard Lampitt and Jeremy Young in article on “Coccolithophore”
Right, Wikipedia article on “Foraminifera”, author Psammophile
Exhibit 3-6: Geographical variation in net primary productivity
of the world’s oceans
Source: Schlesinger (1991)
Exhibit 3-7: Variation of potential pCO2 in the low-latitude ocean
Source: Broecker and Peng
Fraction of Injected Gas Remaining
in the Atmosphere
Exhibit 3-8: Impulse responses – the variation in the amount of a GHG
remaining in the atmosphere after a “pulse” (sudden) emission at time t=0.
1.0
N2O
0.8
CO2
0.6
0.4
CH4
0.2
0.0
0
50
100
150
Years after Impulse
Source: Harvey (2000, Global Warming: The Hard Science, Prentice Hall)
200
Exhibit 3-9: Simulated variation in the terrestrial biosphere sink using the
LPJ dynamic global vegetation model driven either by observed
temperature and precipitation variations (CRU Climatology) or with
output from two climate models
Source: Fischlin et al (2007, IPCC AR4, WGII)
Exhibit 3-10: CO2 emissions and CO2 sinks for a scenario where trend
of increasing emissions turns around between 2010-2020.
Source: Harvey (1989, Climatic Change, Vol. 15, 343-381)
Exhibit 3-11: Methane escaping from thawing yedoma (loess)
soils in Siberia
Exhibit 3-12: Sonar image of methane bubbles rising from the sea floor
along a 2.5 km segment in 250-m deep water west of Svalbard (Arctic
Ocean)
Methane bubbling from lakes
http://www.youtube.com/watch?v=eM5WPl69Z18&feature=related
Source: Kerr (2010, Science, Vol. 329, 620-621)
Video, methane from frozen lakes, ignited
http://www.youtube.com/watch?v=oa3M4ou3kvw
Methane bubbling from lakes
http://www.youtube.com/watch?v=eM5WPl69Z18&feature=related
Exhibit 3.13a: CO2 stabilization scenarios
Exhibit 3-13b: Range of CO2 emissions permitted for the
various stabilization scenarios