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Plate tectonics controls global climate change by determining the frequency of major explosive, subduction-
related volcanic eruptions causing incremental global
cooling
the extent of subaerial, rift-related, effusive, flood basaltic lava flows causing sudden global warming,
ocean acidification, mass extinctions, and often the ends of geologic eons, eras, periods, etc.
versus
Peter L. WardU.S. Geological Survey retired
Science Is Never [email protected] Jackson, Wyoming
WhyClimateChanges.com
This talk is available at https://youtu.be/0e1OIOZE-9E
1. Climate change is controlled primarily by sub-aerial volcanism
2. Frequent major explosive eruptions cause incremental GLOBAL cooling
3. Flood basaltic eruptions, on the other hand, cause sudden GLOBAL warming
4. Sudden major warming followed by slow cooling occurs as often as every1000 years in erratic sequences that are clearly not cyclic. Rate is surprising
5. Plate tectonics determines which type of volcanism is dominant at any time
6. These distinctive sequences of volcanism appear to provide another tool,much like magnetic anomalies, for interpreting the geologic record includingcross-correlation and dating
Key points
Aerosol forming
explosive eruptions
Occur in rift zonesDeplete ozone warming Earth GLOBALLY
many degrees within years
Occur above subduction zonesForm aerosols cooling Earth
GLOBALLY ~0.5oC for ~3 years
Aerially extensive
flood-basaltic eruptions
Climate effect is determined by number of eruptions per century
Climate effect is determined by duration and aerial extent
versus
Pinatubo 1991 Bárðarbunga 2014
Ocean temperature
Ocean crustproduction
Onset Antarcticglaciation
Izu-Bonin-Mariana, Aleutians, southern Rocky Mountains,
Sierra Madre Occidental
Himalayanmountainbuilding23-16 Ma
Mid-mioceneclimate
optimum
Cogné &Humler
2006
Major cooling when there is major subduction
VeizerEt al.1999
Ward2009
Major Pacific Plate
subduction
18Stack of 57 globally distributed deep sea δ O records18
125 100 75 50 25Thousand years before presentLisiecki et al. 2005
Erratic sequences of rapid warming followed by slower coolingDansgaard-Oeschger events observed in Greenland ice
FootprintsSudden warming
Slow coolingErratic sequences
Holocene temperatures and volcanism
Zielinskiet al.1996
Mayewski et al., 1995
Greenland Ice Sheet Project 2
WhiteEt al.1997
Basaltic volcanism ended the last ice age
12,000to
9500
12 of 13 best dated tuyaswere active
during this time
Bollingwarming
Peter S. Giles, 2012
Paleozoicbrachiopod
habitattemperatures
DeccanBasalts
SiberianBasalts
SiberianBasalts
CentralAtlantic
MagmaticProvince
DeccanBasalts
7,000,000 km2 11,000,000 km2 500,000 km2
96% marine70% terrestrial
vertebrates
Examples of flood basalts and large igneous provinces
Extrusion of basaltic magma reached a peak 56 million years ago
during the rifting of theGreenland-Norwegian Sea
Storey et al. 2007 Courtillot and Renne 2003Ages of effusive flood basalts
Ages
of m
ass e
xtin
ctio
ns
Typically end geologic eras,periods, and
epochs
Association with end of time unitsPaleocene-Eocene Thermal Maximum
Siberian basaltsDeccan basalts
Ages of LIPs from Ernst 2014
PETM
CAMP
Ethiopia
Columbia
Madagascar
Kerguelen
Parana
Karoo
MackenzieUmkondo
Guibei
Kalkarindji
Kola-Dnieper
Geological Society of America Time Scale
Emeishan basalts
Uatuma
Snowball Earth
Katian?
Pleistocene
Jurassic ice age
Karoo
Hirnation
Only 104 ages since 540 Ma
17 largest out of >200 LIPS
The balance of effusive and explosive volcanism explains climate change in detail
Large Igneous Provinces punctuate the geologic time scale
1. Climate change is controlled dominantly by sub-aerial volcanism
2. Frequent major explosive eruptions cause incremental GLOBAL cooling
3. Flood basaltic eruptions cause sudden GLOBAL warming
4. Sudden major warming and slow cooling occurs as often as every1000 years in erratic sequences that are clearly not cyclic
5. Plate tectonics determines which type of volcanism is dominant at any time
6. These distinctive sequences of volcanism appear to provide another tool,much like magnetic anomalies, for interpreting the geologic recordincluding cross-correlation and dating
Greenhouse gases simply do not absorb a broad enough range of
frequencies, known of as heat, to be a significant cause of global warming
LEDBroad
continuum of frequencies
Selected frequencies
Lessthan16%
A light bulb emits a broad range of
frequencies (heat) just to produce a narrow range of
visible light
LEDs emit a narrow range of visible
frequencies without emitting heat
Planck’s law (1900)
Frequencies absorbed by carbon dioxide
Greenhouse-warming theory appears to be mistaken