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Milestones in the evolution of the atmospherewith reference to climate change and mass extinctions
Andrew GliksonResearch School of Earth Science and Planetary Science Institute
Australian National UniversityApril, 2008
Climate forcing factors and atmospheric statesAtmospheric states with time, emergence and the evolution of lifeLong term climate trendsEpisodic mass extinctions
MARS (D 6796 km)-113OC to 0oC ; thin atmosphere 0.01 Bar at surface; CO2 95.3%; O2 0.13% of O2 on Earth
VENUS (D 12 100 km) >450OC 90 Bar at surface; CO2 & sulphuric acid
EARTH (D 12,756 km)mean T +18oC (-50 to+55oC)(without the greenhouse effect mean T -14oC);1 bar; N 79%, O2 20% CO2 ~250-300 ppm 2006:~381 ppm CO2
4.4 Ga zirconNanobes Courtesy: P.J.R. Uwins
1.0 mic
H2O
3.95 Ga Stromatolite
6CO2 + 6H2O→C6H12O6 + 6O2
Mesosphere
Ionosphere
Troposphere
Stratosphere
350 km
Ozonelayer
Tropopause
O2 CO2
O2CO2
LUNGS OF THE EARTH
CLIMATE FORCING FACTORS
“Paleoclimate data show that the Earth’s climate is remarkably sensitive to global forcing. Positive feedbacks predominate. This allows the entire planet to be whipsawed between climate states. A climate forcing that ‘flips’the albedo of a sufficient portion of an ice sheet can spark a cataclysm.”Hansen et al., 2007 (J. Royal Society)
ORBITAL FORCING
GREENHOUSE GASES AND AEROSOLS
THE ICE ALBEDO FLIP
ORBITAL FORCINGCl
imat
ic pr
eces
sion
Obliq
uity
Time (thousands of years)
Ecce
ntric
ity
Eccentricity period 95-135 kyr
Precession period 20-26 kyr kyr
Axial tilt period ~40 kyr
Sunspot cycle +/-1.5 W/m2
1 W/m2 ~ 0.75 oC
Sun spot frequency
The maximum global mean forcing since 1750 due to orbital variations = about 0.25 Watt/m2
(Hansen et al., 2007, Roy. Soc. London)
Eccentricity: Circular, elliptic, parabolic or hyperbolic trajectories.Precession: Change in the direction of the Earth's axis of rotation relative to the Sun at the time of perihelion and aphelion. Obliquity: Earth axial tilt relative to the ecliptic plane
CLIMATE SENSITIVITY AND AEROSOL EFFECTS
ATMO
SPHE
RIC
CO2 B
Y 21
00
TEMP
ERAT
URE
CHAN
GE B
Y 21
00
PRESENT-DAY AEROSOL FORCING w/m2
PLANTSProduction of oxygen
Regulation of carbon dioxideAccumulation of methane, pit and coalRegulation of ground water levelRegulation of local temperatures and rainfallExtensive fires — tinderbox Earth
ANIMALSAbsorption of oxygenEmission of CO2 and CH4
O2CO2
O2
ANTHROPOGENICAbsorption of oxygenEmission of CO2Extra-emission of CO2
BIOLOGICAL FORCING: THE ATMOSPHERIC RESPIRATION SYSTEM
CO2
THE GREENHOUSE EFFECT (natural balance)(Radiative forcing units Watt/m-2)
Earth surface with no greenhouse effect: mean T -18oCEarth surface - greenhouse effect: mean T +14oC
GREENHOUSE EFFECT/CLIMATE SENSITIVITYDoubling of CO2 ~2 to ~4OC since 1750, i.e.+280 ppm for +3oC1 pm CO2→0.0107oC100 ppm → ~1.0oC
Solar radiationat the top of the
atmosphere 342 W/m-2 Reflection from the top of the atmosphere
77 W/m-2
Reflection (albedo)from the Earth surface
30 W/m-2
AtmosphericAbsorption
67 W/m-2
Reaching the EarthSurface 168 W/m-2
IR radiation Emitted from the
Earth surface390 W/m-2
155 W/m-2
Re-emitted towardthe Earth surface by greenhouse gases
1 Watt/m2 = 0.75oC
H2O, CO2, CH4, N-oxides
235W/m2
O == C == 0 variable
LOWER CRETACEOUS110 – 90 Ma >1000 ppm CO2; ~7oC warmer that at present
Deep ocean basins (dark blue) and shallow inland seas (light blue) are shown in this view of the Earth 110 million years ago (Cretaceous Period). Note the opening of the central Atlantic Ocean caused by rifting between North America (upper left) and Africa (lower right). Image by Ron Blakey, Northern Arizona University.
Global Climate Change and the Cretaceous Greenhouse World by Greg A. Ludvigson
EXTREME ATMOSPHERIC STATES: GREENHOUSE WORLD
(Cryogenian 850-630 Ma)
ICE THICKNESS (METRES)
TEMPERATURE (Oc)
PRECIPITATION (MM D-1)
Computer simulation of conditions during the Snowball Earth period Hyde et al (2000) Nature 405:425-429
Solar luminosity –4%CO2 as low as 40 ppm?
EXTREME ATMOSPHERIC STATES: SNOWBALL EARTH
5 10 15 20
GLOBAL MEAN TEMPERATURES (OC)
Climate Change Fact Sheet Compiled by Prof. Stefan Rahmstorf Potsdam Institute for Climate Impact Research (www.pik-potsdam.de/~stefan)
100
50
0
-50
-100
-150
SEA
LEVE
L (M
ETRE
S)
Last Glacial Maximum
20 kyr
Eocene ~40 Ma
Pliocene ~3 Ma
SEA LEVEL CHANGES BETWEEN EXTREME CLIMATE STATESSEA LEVEL AMPLITUDE >200 METRES
~22 metre/1o C
~4 to 18 metre/1oCToday
EARLY STAGESEA LEVEL RISE?
< 1 metre 2100 IPCC projection
?
EXTRATERRESTRIAL FORCING AND ENDOGENIC RESPONSES
EPISODIC EXTRATERRESTRIALO IMPACT AND ENDOGENIC VOLCANIC FORCING
305 GtC EMITTED SINCE 1750
TOTAL ESTIMATED FOSSIL CARBON RESERVES~ 4000 GtC
“Late Cretaceous/Early Tertiary background CO2 levels of 350-500 ppm by volume, With a marked increase to at least 2,300 ppm by volume within 10,000 years of the KTB impact, due to instantaneous transfer of approximately 4,600 GtC to the atmospheric reservoir by a large extraterrestrial bolide impact. A resultant climatic forcing of +12 W/m2 would have been sufficient to warm the Earth's Surface by approximately 7.5 degrees C, in the absence of counter forcing by sulfate aerosols. Beerling et al., 2002, PNAS, 99, 7836-7840
ATMOSPHERIC STATES WITH TIMEAtmospheric states with time, emergence and the evolution of life
1718
19
20
21
22
23 13
14
16
24
PMAM
Asteroid/comet impacts volcanic activity glaciation red beds banded ironstones biogenic events mass
011
10
9
8
7 6 5
4
3
1
2
154000M
1140M
1710M570 BYO2
pH
2860M
3420M
48% KT extinction(Dinosaurs)
4560M PRESENT
Milestones in terrestrial evolutionBipedalism ~5 my – last 1 minute 35 secondsStone tools ~ 3 my – last minuteFire ~700 000 yr – last 13 secondsBurial ~ 100 000 yr – last 2 secondsNeolithic ~ 12 000 yr – last 0.24 seconds
78% PT extinction2400-2200m
600-800m
300
0.0
20
THE EARLY ATMOSPHERE
Low solar luminosity (-70-80%), compensated by super-greenhouse effect (due to high CH4, H2O, CO2, CO, H2S, polymerized hydrocarbons)Evidence of low O2 from unoxidized pyrite & uraninite in sediments and abundance of ferrous iron – forming banded iron formations.Some oxygen available (according to S isotope studies). High temperatures of the hydrosphere, due to high geothermal gradients and greenhouse effects.CO2 supplied by volcanic activity, but low sequestration due to high water temperatures (evidenced by scarcity of carbonates pre-2.7 Ga) and limitederosion due to low continent/ocean ratio. Anoxic, reducing, sulphur-rich oceans constrained biological evolution of allbut the most primitive single-cell prokaryotes lacking in nucleus, includingmethanogenic bacteria and cyanobacteria (forming stromatolites).
Model of ancient stratified ocean with cyanobacteria colonizing surface mixed layer, above layer of anoxygenic photoautotrophic Fe(II)-oxidizing bacteria, with a hydrothermal source of Fe(II) underneath (Holland, 1973; Morris, 1993). Question mark and double arrow point to thickness of layer of anoxygenicphototrophs supported by Fe(II) input. After Kappler et all., Geology, 2005
cyanobacteria mixed layer
Hydrothermal Fe+2
Fe+2Fe+3 (OH)3
Photic depth
Anoxygenetic Fe+2
oxidizing phototrophs
BIF DEPOSITION
Fe-poor chert
O2
BIOGENIC ORIGIN OF BANDED IRON FORMATION
6Fe+2 + 0.5O2 + CO2 + 16H2O → [CH2O] + 6Fe(OH)3 + 12H
MILESTONES IN THE EVOLUTION OF LIFE FORMS
Ediacara
Sulphur-rich oceans CO2-rich reducingAtmosphere (detrital Sulphide, uranitite, sulphur isotopes)Soluble ferrous oxide
0.6 B.Y.
3.42 B.Y. stromatolites
3.49 B.Y. stromatolites
2..1 Ga 1.5 Ga Mitosis 0.54 GaMulticelularAnimals;calcareous shells
2.73 B.Y. stromatolitesBanded ironstones / possible Bacterial deposits Oldest – 3.85 B.Y.
Archaea
Apex microfossils (3.47 B.Y.)
OXYGEN ENRICHMENT
Stromatolites: past and present
A. 2.63 Ga giant stromatolite, Carawine DolomitePilbara, Western Australia.
B. Shark Bay stromatolites.
THE “CAMBRIAN EXPLOSION”2 cm
Trilobite
DickinsoniaCostata: Ediacaran
Halkiera: mid-Cambrian
Molusc-like fossil 555 Ma
Microscopic sponges
Opabinia BW
Increase in oxygen was Needed to produce the protein Collagen Connective tissue required to Form complex animals
Antrim Basalt:Mass extinction513+/-12 Ma
Long term climate trends
AGE (Ma) (variable scale)
Supe
rior
glac
iatio
n
Stur
tian/
Merin
oan
Glac
iatio
n (lo
w at
m. C
O2)
C-P
glac
iatio
nGREENHOUSE EARTH
DESCENT INTO GLACIAL/INTERGLACIAL
OCEAN GAP/SPREADING/VOLCANISM/CO2 RELEASE
CO2 SEQUESTRATION/OXYGEN ENRICHMENT
EVENTS
Present
War
mCo
ld
Ocea
ns to
o wa
rmTo
sequ
este
r CO2
Dense vegetation/CO2 sequestrationLow atm CO2Dense vegetation/
CO2 sequestration
ONSET OFLAND PLANTS
O2Low pH; high
CH4 & H2S
251
GREENHOUSE EARTH
513 Ma
374 Ma58% EX
200 Ma35% EX
182 MaFerrar
65 Ma48%EX
145 Ma20% EX
251 Ma78% EX
488 Ma41% EX
265 Ma49% EX
MAB
LAND
PLA
NTS
ABUN
DANT
VEG
ETAT
ION
JURA
SSIC
FOR
REST
S
513 Ma40% EX
CO2 FORCING OF ATMOSPHERIC TEMPERATURES
Land
plan
ts
PTLT KT
CO2 r
elativ
e to
(pre
-indu
stria
l leve
ls) 23
0 ppm
CO2 LEVELS THROUGH TIME RELATIVE TO PRE-INDUSTRIAL AGE LEVELS
Time (Million years)
Mammals proliferate
230 ppm CO2
1150 ppm
2300 ppm
3450 ppm
Amphibians / Lizards (cold blooded)Dinosaurs (warm blooded)
Advent of land plants –
CO2-ABSORPTION
387 ppm CO2
Dana L. Royer, 2002
Time (million years)
% o
f O2 in
the a
tmos
pher
e
OXYGEN LEVELS AND BIOLOGICAL EVOLUTION
LATE
DEV
ON
IAN
EXT
INC
TIO
NS
PER
MIA
N-T
RIA
SSIC
EXT
INC
TIO
N
END
-CA
MB
RIA
N E
XTIN
CTI
ON
S
CARB
ONIF
EROU
S-PE
RMIA
N GL
ACIA
TION
(c
ause
d in
par
t by p
lant a
bsor
ptio
n of
CO2
)
TRIA
SSIC
-JU
RA
SSIC
EXT
INC
TIO
N
QU
AR
TRN
AR
Y G
LAC
IATI
ON
APP
EAR
AN
CE
OF
LAN
D P
LAN
TSA
ND
AN
THR
OPO
DS
ASTEROIDIMPACT
VOLCANISM
Low-
O 2 / fa
st fi
shBi
olog
ical d
ivers
ifica
tion
Coal
form
atio
n / g
igan
tism
(rep
tiles
and
arth
ropo
ds)
Incr
ease
d m
amm
alian
size
Nove
l air
sect
ion
orga
ns in
din
osau
rs / b
irds
Prol
ifera
tion
of an
thro
pods
and
fish
STOMATA (CO2 capture perforation)
Episodic mass extinctions
Meteorite cruster
Asteroid impact
Volcanism
Methane eruption
CORRELATIONS BETWEEN IMPACTS, VOLCANISM AND MASS EXTINCTIONSCrutzen P.J. and Stoermer, E.F., 2000. The “Anthropocene”. Global Change Newsletter 41, 12-13 Glikson, A.Y., 2008. Milestones in the evolution of the atmosphere with reference to climate change. Aust. J. Earth Science, 55, 123-127.Keller, G., 2005. Impacts, volcanism and mass extinction: random coincidence or cause and effect? Australian Journal of Earth Sciences 52, 725 – 757.Ruddimann, W.F., 2005. Plows, Plagues, and Petroleum: How Humans Took Control of Climate, Princeton University Press.Ruddimann, W.F., Varvus, S.J., Kutzbach, J.E., 2003. Test of the overdue-glaciation hypothesis, Quaternary Science Reviews 24.Schmitz, B. et al., 2008. Asteroid breakup linked to the great Ordovican biodiversification event. Nature Geoscience 1, 49-53Sepkosky, J. J. JR 1996. Patterns of Phanerozoic extinction: a perspective from global data bases. In: Walliser O. H. ed. Global Events and Event Stratigraphy, 35 – 52, Springer, Berlin.
Stanley, S.M., 1977. Extinction. Scientific American Library, W.H. Freeman and Co.,
New York
Munta 1
ACRAMAN IMPACT ACRYTARCHS EXTINCTION - RADIATION
Acraman ejecta layer
Grey et al., 2003
Araguinha impact 252.7±3.8 Ma
0
2
4
6
8
10
RCO2
Fbg
-270 -265 -260 -255 -250 -245 -240
Time Ma
Fbg
RCO2 P Tr
CO2 RISE AND REDUCED BURIAL OF ORGANIC MATTER AT THEPERMIAN-TRIASSIC BOUNDARY
RCO2 - ratio of CO2 mass in the atmosphere to that at present (Pleistocene mean 250 ppm). Fbg - burial rate of organic matter in 10^18 moles/ million years.
TIME (Ma)
2500 ppmCO2
RCO2
P. Ward, 200713C
isoto
pic d
iverg
ence
from
org
anic
carb
on st
anda
rdPermian
Triassic Jurassic
TertiaryCretaceous
Triassic
Carbon isotopic evidence of mass extinctions across geological boundaries
High
bio
logi
cal a
ctivi
tylo
w bi
olog
ical a
ctivi
ty
Royer, D.L., Wing, S.L., Beerling, D.J. et al. (2001) Palaeobotanical evidence for near present-day levels of atmospheric CO2 during part of the Tertiary. Science, 292, 2310-2313
METHANE ERUPTION:Paleocene-Eocene thermal maximum (PETM) 55 Ma
The descent into Quaternary ice ages
Global deep ocean δ18OAntarctic ice sheet
North hemisphere ice sheets0
1
2
3
4
5
δ18O‰
Deep
oce
an te
mpe
ratu
re o C
60 50 40 30 20 10 0
TIME (Ma)
Global deep ocean δ18O‰ values and temperatures with time Age resolution +/- 0.5 m.y.
Paleocene Eoecene Oligocene Miocene Pliocene33.7-23.7
Ma55 – 33.7
Ma23.7-5.3
Ma5.3-1.0
Ma
Pleistocene1000 – 10 kyrHolocene10 kyr – 1750ADAnthropocene – 1750AD - ?
Oligoceneglaciation
Paleocene-EoceneThermal maximum
12
8
4
0
CH4
HIGH SEA LEVELS LOW SEA LEVELS
Chicxulub Popigai, Chesapeake Bay Youngest dryas?
(Hansen et al., 2008)
Paleocene 66-52 Ma
Eo-Olig 37-30 Ma Olig-Mio 30-10 Ma
Cretaceous
Eocene 52-37 Ma
Mio 10-5 Ma Pliocene 5-2 Ma 2 Ma – 10kyr
AUSTRALIA PALAEO-MAPS
Geoscience Australia Atlas
~3 Ma Mid-PlioceneThermal (+20C to +30Cand SL (25+/-10 m) rise
~0.7 Ma Discoveryof fire by Homo
QUATERNARY CRISES
TER-0 Ters-I, II, III, III
Australopithacus
Homo Erectus
Fire-enhanced peaks?
MID-PLIOCOENE ~3 Ma TEMPERATURE ANOMALIES(R. Chandler, 1997 NASA Goddard Institute of Space Science)
∆oC
Images based on Global Gridded Pliocene and Late Quaternary Sea Level, U.S. Geological Survey Open-File Report 96-000, Peter N. Schweitzer and Robert S. Thompson. http://chemistry.beloit.edu/Warming/sealevel/index.html
120 METER LOWSTANDDURING THE
LAST GLACIAL
35 METRE HIGHSTAND IN THE MID-PLIOCENE 3 Ma AGO
THE MID-PLIOCENE ANALOGY OF CURRENT CLIMATE CHANGE
“The salient feature of terrestrial climate change is its asymmetry. Global Warming events are usually rapid, followed by slower descent into colder climate. Given the slow pace of the weak orbital forcings and the magnitude of glacial-to interglacial climate change, the cause of rapid warming at glacial “terminations” must lie in a climate feedback”(Hansen et al., 2007. Roy. Soc. London)
Orbital forcing (June 65oN) ~ 40-100 W/m2
INTERGLACIAL ONSETSSOLAR-TRIGGERED GREENHOUSE + ALBEDO-FLIP EVENTS
Albedo flip(ice/snow/vegetation)~3.0-4.0 W/m2
Greenhouse gasCO2, CH4, NOxforcing~3.0 W/m2
1 W/m2 = 0.75 oC
Estimates of sea levels during Termination-II 135-110 kyr (Siddall et al., 2006)and termperatures from the Vostok ice core (Petit et al., 1999)
THE TERMINATION-II ANALOGY
110 115 120 125 130 135 Kyr
- 6oC
+ 3oC0
- 3oC
- 6oC
+ 9oC
VOSTOK
EPICA
Sea L
evel
ICE VOLUME
SEA LEVEL PEAK LAG>5000 YEARS FROMPEAK TEMPERATURE
PEAK
TEM
P
PEAK SL
MIN.
ICE
VOLU
ME
MAX
SEA
LEVE
LS
100Years
Dansgaard-Oeschenger warming events
20000
15000
10000
5000
disc
harg
e (km
3 /yea
r)
30
20
10
0
%lit
hics
(glac
ial d
ebris
)
70 60 50 40 30 20 10 Kyr
North Atlantic Heinrich events, ice melt and sea level rises (Salzman, 2002) Older
dryasYounger dryas
0.5
0.4
0.3
0.2
0.1
Sea L
evel
chan
ge (c
m/ye
ar)
20 18 16 14 12 10 8 6 4 2 0 kyr
Heinrich glacial debris deposits North Atlantic ocean
ABRUPT CLIMATE CHANGE
Central Greenland ice core (GISP2)
For the best-characterized warming, the end of the Younger Dryas cold interval 11,500 years ago, the transition in many ice-core variables was achieved in three steps, each spanning 5 years and in total covering 40 years. However, most of the change occurred in the middle of these steps. The warming as recorded in gas isotopes occurred in decades or less (Alley, 2000, PNAS, 97, 1331-1334).
Accumulation (m
eters ice/year)Te
mper
ature
s o C+12oC (POLAR)
in 40 years
Sea l
evel
-120
+20
YD OD
NF
Age (thousands of years before present)
END-GLACIAL (termination-I) SEA LEVEL RISE
OLDE
R DR
YAS
+20
0
-20
-40
-60
-80
-100
-120
AGE KYR BP
SEA
LEVE
L (M
ETRE
S) (r
elativ
e to
mea
n 0-
7000
yrs)
Siddall et al., 2003
+0.35 cm/year
+1.7c
m/ye
ar
2.8 cm
/year Ice core temperatures
(Alley, 2000)
YOUN
GER
DRYA
S
• Last 450,000 years:Vostok ice core record(blue)
• Last 100 years:Contemporary record(red)
• Next 100 years: IS92A scenario(red)
ANTHROPOGENIC FORCINGAtmospheric CO2 levels last 450,000 years
CO2
CONC
ENTR
ATIO
N (P
PMV)
AGE OF ENTRAPPED AIR (103 YEARS)
CURRENT 2006
"Sea surface temperatures within 1oC of the warmest interglacial periods over the past million years.“
James Hansen (NASA’s chief climate scientist, 2007)
Western Equatorial Pacific Sea Surface Temperatures Indian Ocean SST
Kyr Date Kyr Date1350 1000 500 150 75 1870 2006 150 75 1870 2006
Tem
pera
ture
(o C)
30
29
28
27
26
30
29
28
27
26
2001-2006 mean2001-2006 mean
1870-1900 mean
1870-1900 mean
6-8 m SLR>8 m SLR
2000-2005 +0.15oC
COMBINED TEMPERTATURE EFFECTS OF GREENHOUSE EMISSIONSAND THE SOLAR SPOT CYCLE
Sunspot cycle (+/-1.5 W/m2)
1900 2000~1
980-
2000
+0.4o C
http://www.skepticalscience.com/Global-warming-stopped-in-1981.html
Tota
l sol
ar ir
radi
ance
W/m
2
1371
1370
1369
1368
1367
1366
13651975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007
Monthly Land-Ocean temperatgure anomaly (NASA GISS)
Total solar irradiance
Tem
pera
ture
anom
aly o C
+0.8
+0.6
+0.4
+0.2
0
-0.2
-0.4
-0.6
+0.56oC since 1975
CLIMATE TIPPING POINTS
N.H.
Tem
pera
ture
(°C)
0
0.5
1
-0.5
1000 1200 1400 1600 1800 2000
2
4
3
5
6
1
0
Glob
al T
empe
ratu
re (°
C)
IPCC Projectionsfor 2100 AD
Earth System moves to a new state;modern civilization collapses
Feedbacks push climate change higher;abrupt changes much more likely;massive impacts to humans
Loss of Greenland ice sheet= 6.4 metre sea level rise
Large biodiversity loss;coral reefs disappear
“Committed” Climate Change
IPCC PROJECTIONS
YEAR
BACK TO THE EOCENE
CO2 >550 ppm
The life force
NanobesCourtesy: P.J.R. Uwins
1.0 micron
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