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FrankenClimateThe Perils of Engineering Our Way Out
of Global Warming
Supported by the Deep Earth Academy; www.deepearthacademy.orgUsing deep sea evidence to make inference about Earth’s past, present, and future
Gabriel FilippelliProfessor of Earth Sciences, IUPUIDirector, Center for Urban Health
“The 21st century is going to be a wild ride in terms of natural resources. We need to rethink the ways we’re using and consuming resources…while dealing with climate change.”
John Ochsendorf
Outline• Be afraid…be very afraid
– Climate impacts, future
• “It’s Alive!”– Geo-engineering to confront global warming– Premise behind Iron Fertilization
• “Where’s the beef?”– Looking to the deep sea to see how nature worked in the
past
• Don’t worry, be happy– Simpler ways to confront/adapt to climate change
Jakobshavn Ice Stream in Greenland
Tibet
Be afraid…be very afraidWhy worry about climate change?
• Melting Ice…no Ice PACs
Why worry about climate change?
• Extreme Weather• Ocean Acidification• Droughts/Floods• Coastal Security• Ecosystem disruption• Food security risks• Inter-nation strife
Inconvenient for some people and countries, catastrophic for others
Why is climate change occurring? or, “Same as it ever was”
• Greenhouse gasesWater vapor – passive,
responds to temperatureCarbon dioxide, methane,
CFCs – active, store reflected IR as heat in atmosphere
Sources – combustion of fossil fuels; deforestation and soil loss; rice cultivation and ruminants; synthetic chemicalsYear
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2010
Atm
osph
eric
Car
bon
Dio
xide
con
cent
ratio
n (p
pm;
Mau
na L
oa)
310
320
330
340
350
360
370
380
390
My daughter’s first breath
My first breath
But I can’t do anything about it!
Carbon dioxide experiment as cause and cure
I was born
My daughter was born
My great granddaughter is born?
Iron Fertilization experiments
Problem—blooms don’t last long, dominated by one species, yield unexpectedly low carbon effect
Geo-engineering solution to an environmental problem
The addition of iron, a potentially limiting nutrient for biological productivity in some parts of the ocean:
1. Is “natural”2. Spurs plant growth3. Increases carbon dioxide uptake from the atmosphere4. Reduces the Greenhouse Effect
So, no bad effects?Ecosystem disruption, anoxia (think Gulf Dead Zone)
But who holds the switch?
Who decides when it is cool enough? How is it sustained over centuries? Who pays?
It’s Alive!
“It is essential that we have a back-up plan--if geoengineering is that plan, it had better be well researched, well ahead of time.”
And Now What?
• Destroying warrens through ripping, blasting• Fumigating• Poisoning with sodium fluoroacetate• Ferrets• Spreading rabbit-borne diseases myxomatosis,
calicivirus; but need to vaccinate bunnies you want—remember the Easter Bunny, please!
How Does History Rate Us?
• DDT increased agricultural yields, decreased malaria
• But what the chemists hadn’t thought about…
• Extremely persistent in the environment
• Accumulates in organisms• Scrambles reproductive cycles• DDT-tolerance quickly emerged
Unintended Consequences
Law of unintended consequences
an intervention in a complex system tends to create unanticipated and often undesirable outcomes
One unintended consequence—fossil fuels cause global warming. Are we willing to add another…?
Wind-driven Iron FertilizationWind-driven Iron Fertilization
High dust during glacial times fertilized the ocean around Antarctica, making it much for productive thus pulling down atmos. CO2
Vostok CO2 (ppmv)
Petit et al. (1999)
160 180 200 220 240 260 280 300 320
age (kyr)
0
50
100
150
200
250
300
350
400
450
Modern values for Southern OceanDust 0.2 mol m-2 yr-1
Upwelling 8 – 16 mol m-2 yr-1
Assumption—little variation in upwelling flux, large variations in dust flux synchronous with pCO2 changes
We can mimic natural dust addition by dumping iron on the surface, fueling the biological capture of CO2
Hmmm……
But, the biological action was in the oceanCan confirm hypothesis by looking at past ocean conditions
Paradigm—fertilization from above
What did we find?
P/T
i (g/g
)
0.1
0.2
0.3
0.4
0.5
0.6
P A
ccum
ula
tion
Ra
te
( m
ol cm
-2 kyr
-1)
0
400
800
1200
1600
Fe
Accu
mu
latio
n R
ate
( m
ol cm
-2 kyr
-1)
0
10
20
30
40
50
60
age (kyr)
0 100 200 300 400 500 600
Vo
stok D
ust (p
pm
)P
etit e
t al. (1
99
9)
0.0
0.5
1.0
1.5
2.0
Region Glacial Interglacial Reference
Southern Ocean 300 – 3000 100 – 200 Latimer and Filippelli (2001)
Southern Ocean 850 – 1400 100 – 250 Kumar (1995)
Southern Ocean 20 – 40 2 Duce and Tindale, (aolian) 1991; Petit et al., 1981
Equatorial Pacific 50 – 200 10 – 30 Murray et al., 1995
Much Higher Fe Sedimentation during glacial periods
Much higher indeed than the dust values…iron fertilization fueled from below?
Upwelled Iron Model
FeFe FeFe Fe
Shelf sedimentation dominatesLittle turbidite activityRelatively “clean” deep oceanIron limitation
Shelf sedimentation reducedTurbidites activatedRelatively “dirty” deep oceanHigher dissolved Fe in deep and midwatersIron fertilization of productivity in ‘HNLC’
regions
Dirty Glacial ocean from high sediment loads to the deep sea
Some iron dissolved from those sediments, upwelled into surface ocean, in proper form to fuel biological activity
Upwelled iron included the other essential nutrients for plant growth
The reason why the Fe fertilization experiments did not yield satisfactory results in terms of CO2
Paradigm Lost?
=
“Give me a half a tanker of iron, and I’ll give you an Ice Age”
• Not likely how this process acted in the past• Unclear whether the productivity response observed can be
sustained due to rapid downwelling of iron• Implications of large-scale ecosystem modification not well
understood
Novel idea:Novel idea:If we want to bring down carbon levels in the If we want to bring down carbon levels in the
atmosphere, why not invest in emitting less? atmosphere, why not invest in emitting less?
Summary• Be afraid…be very afraid
– Climate impacts and causes clear, future is ours
• “It’s Alive!”– Geo-engineering to confront global warming– Premise behind Iron Fertilization might be flawed
• “Where’s the beef?”– The deep sea holds many examples of “natural”
experiments that are informative for our future
• Don’t worry, be happy– Simpler ways to confront/adapt to climate change
• Not ifif, but whenwhen and how muchhow much are now the cogent questions related to climate change
• Fighting a warming world—based on the concept of modulating the increase in atmospheric carbon dioxide– Carbon emission restrictions– Efficiency, alternative sources, carbon sequestration
• Living in a warming world—based on the concept that even with controlled emissions, warming will occur– Consider coastal security– Consider agricultural security, water supply security
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