Based on Greenland and Antarctica
ice core studies:
The rise and fall of Earth's surface temperatures led the rise and fall of carbon dioxide (CO2) concentrations in the air by hundreds of years, (for at least the past 800,000 years that are covered by ice core studies).
Reason:
As oceans warmed from natural causes, they gradually released some of their vast stores of dissolved CO2.
As oceans cooled from natural causes, they gradually absorbed more CO2.
The lowest CO2 levels on record, based on ice cores, were during cold periods when ice sheets covered much of the Earth, such as 20,000 years ago.
At maximum glaciation, CO2 concentrations were under 200 parts per million (ppm) -- less than half the current CO2 level of 400 ppm.
Under 200 ppm is a CO2 level that stunts the growth of green plants, which prefer 800 to 1,200 ppm for maximum growth.
The ice core record shows surface temperatures warmed up from natural causes at least several hundred years BEFORE CO2 concentrations began rising.
This multi-hundred year lag supports a conclusion that natural temperature changes DRIVE changes in CO2 levels, not the current claim that man made CO2 levels drive temperature changes.
New Research:
Geothermal heat fluctuations lead both temperature and CO2 changes by thousands of years.
Heat flux from below melts ice sheets, and drives temperature & CO2 variations.
Russian geophysicists Demezhko and Gomostaeva (2015) recently found the geothermal heat flux from below the Earth’s surface may have risen two to three thousand years before the surface temperatures and CO2 concentrations began rising.
“The increase of carbon dioxide concentrations occurred 2–3 thousands of years later than the heat flux increase and synchronously with temperature response.”
Therefore, the order for heat energy changes may be:
(1) Increase in the heat from under the Earth’s surface,
(2) Earth’s surface temperature rises, and
(3) CO2 concentrations in the air rise.
Greenland warms and glaciers melt significantly due to heat from below:
"Considering the magnitude of heat energy required to melt polar ice sheets from below, and that central Antarctica’s air temperatures average about -55°C year-round, it should not be surprising that a significant portion of the meltwater flow from both polar ice sheets (Greenland and Antarctica) is derived from “heat flow from the deep Earth”.
There is much to learn about geothermal factors and their relationship to the Earth’s climate system.
For example:
More than 70% the Earth’s volcanoes occur under the sea floor, unobserved -- there are more than 100,000 extinct and active locations beneath the ocean depths.
Fluctuations of heat flow from the Earth and subglacial volcanoes may determine:
(1) changes in surface temperatures,
(2) ice sheet melt,
(3) CO2 levels, and
(4) climate change in general.
Remember that a glacier is a moving 'river of ice' -- meltwater at the base of the glacier is the lubricant that promotes movement toward sea level.
It would be wise to continuing studying geothermal heat effects rather than declaring "climate science is settled“ -- that's an anti-science statement, because science is NEVER settled.
IPCC AR4 (2007):
“Atmospheric CO2 follows temperature changes in Antarctica with a lag of some hundreds of years.”
Caillon et al., 2003:
“ ... CO2 increase lagged Antarctic ... warming by 800 ± 200 years ... ”
Fischer et al., 1999:
“High-resolution records from Antarctic ice cores show that carbon dioxide concentrations increased by 80 to 100 parts per million by volume 600 ± 400 years after the warming ... ”
Monnin et al., 2001:
“The start of the CO2 increase thus lagged the start of the [temperature] increase by 800 ± 600 years.”
Kawamura et al., 2007:
“ ... the CO2 rise at [glacial] terminations, which occurs within 1,000 years of the increase in Antarctic temperature.”
Indermuhle et al., 2000:
“The [CO2] lag was calculated (as) ... (1200 ± 700) yr.
Landais et al., 2013:
“ ... there is an unequivocal lead (of temperature) ... over CO2 of 900 ± 325 years”.
Rogozhina et al., 2016:
“Ice-penetrating radar and ice core drilling have shown that large parts of the north-central Greenland ice sheet are melting from below.
"Here we estimate the geothermal flux beneath the Greenland ice sheet and identify a 1,200-km-long and 400-km-wide geothermal anomaly beneath the thick ice cover."
We suggest that this anomaly explains the observed melting of the ice sheet’s base ... ”
Petrunin et al., 2013:
“Here we use a coupled ice–lithosphere model driven by climate and show that the oldest and thickest part of the Greenland Ice Sheet is strongly influenced by heat flow from the deep Earth.”
Fahnestock et al., 2001:
High Geothermal Heat Flow, Basal Melt, and the Origin of Rapid Ice Flow in Central Greenland …
“Locally, high melt rates indicate geothermal fluxes 15 to 30 times continental background.
The southern limit of melt coincides with magnetic anomalies and topography that suggest a volcanic origin.”
van der Veen et al., 2007:
“... the origin of the large geothermal heat flux remains unidentified. Ice-penetrating radar profiles show bright bed reflections in many locations in northern Greenland, indicating the presence of lubricating meltwater at the glacier base.”
Lilja Buchardt and Dahl-Jensen, 2007:
“From radio-echo sounding (RES) surveys and ice core data it can be seen that the ice sheet is melting at the base in a large area in Northern Greenland.
The RES images reveal internal layers in the ice. ... the geothermal heat flux is very high and has large spatial variability in Northern Greenland.”
Dahl-Jensen et al., 2003:
“The results show the geothermal heat flow varies from 50 to 200 mW square meter along the 100 kilometer section of the modeled flow line.”
Fisher et al., 2015:
“We report the first direct measurement of geothermal heat flux into the base of the West Antarctic Ice Sheet (WAIS), below Subglacial Lake Whillans, determined from the thermal gradient and the thermal conductivity of sediment under the lake.
... The high geothermal heat flux may help to explain why ice streams and subglacial lakes are so abundant and dynamic in this region.“
Maule et al., 2005:
“The geothermal heat flux is an important factor in the dynamics of ice sheets; it affects the occurrence of subglacial lakes, the onset of ice streams, and mass losses from the ice sheet base.
We found that the heat flux underneath the [Antarctic] ice sheet varies from 40 to 185 megawatts per square meter and that areas of high heat flux coincide with known current volcanism and some areas known to have ice streams.”
Schroeder et al., 2014:
“Heterogeneous geothermal flux and subglacial volcanism have the potential to modulate ice sheet behavior and stability by providing a large, variable supply of meltwater to the subglacial water system, lubricating and accelerating the overlying ice.
… [H]eterogeneous geothermal flux beneath Thwaites Glacier is likely a significant factor in local, regional, and continental-scale ice sheet stability.”
Corr and Vaughan, 2008:
“Indirect evidence suggests that volcanic activity occurring beneath the West Antarctic ice sheet influences ice flow and sheet stability.
… Ongoing volcanic heat production may have implications for contemporary ice dynamics in this glacial system.”
Vogel and Tulaczyk, 2006:
“Subglacial volcanism in West Antarctica may play a crucial role in the dynamics and stability of the West Antarctic Ice Sheet (WAIS).
... Lubrication [melting ice] of an area, which otherwise should be frozen to its bed, is best explained by basal melt water generated in the vicinity of Mt. Casertz.”
Blankenship et al., 1993:
“Here we present aero-geophysical evidence for active volcanism and associated elevated heat flow beneath the West Antarctic Ice Sheet near the critical region where ice streaming begins.”
Damiani et al., 2014:
“One major contributor to fast glacial flow is the presence of subglacial water, the production of which is a result of both glaciological shear heating and geothermal heat flux.”
Kelley, 2017:
Volcanology: Vulcan rule beneath the sea
… “Over 70% of the volcanism on Earth occurs beneath an ocean veil.
… Satellite data reveal more than 100,000 extinct and active seamounts that mark sites of past and present volcanic activity.
[O]bservations imply that submarine volcanoes may play an important role in cycling carbon and sulfur through the Earth, oceans and atmosphere.”
“[T]he flux of volatiles from these systems remains poorly quantified and the significance of these volcanoes as part of the deep carbon and sulfur cycles on a global scale is unknown.”
Humlum et al., 2013:
http://www.climometrics.org/12hustso.pdf
“There exist a clear phase relationship between changes of atmospheric CO2 and the different global temperature records, whether representing sea surface temperature, surface air temperature, or lower troposphere temperature ... with changes in the amount of atmospheric CO2 always lagging behind corresponding changes in temperature.”
Kovalenko, 2014:
http://link.springer.com/article/10.1134/S1024856014060104#page-1
“Observable correlations between long-term variations in the global temperature (GT) and CO2 content do not mean that the CO2 increase causes an increase in the global temperature.
Actually observable temperature rise in the ocean also results in the increased content of CO2 in the atmosphere; therefore, such changes can be a consequence, but not a cause of global heating.”
Quirk, 2009:
http://journals.sagepub.com/doi/abs/10.1260/095830509787689123
“The constancy of seasonal variations in CO2 and the lack of time delays between the hemispheres suggest that fossil fuel derived CO2 is almost totally absorbed locally in the year it is emitted.
This implies that natural variability of the climate is the prime cause of increasing CO2, not the emissions of CO2 from the use of fossil fuels.”
Source for list of studies above:
Geothermal Heat A Leading Driver Of Surface Temperatures
By Kenneth Richard
May 22, 2017
http://notrickszone.com/2017/05/22/new-paper-geothermal-heat-a-leading-driver-of-surface-temperatures/#sthash.UIAKipf7.dpbs
URL ABOVE INCLUDES LINKS TO ALL STUDIES MENTIONED IN MY ARTCLE