Record Greenland Melt August 2012. This image is from 35 miles inland from the edge of the ice sheet due east from a place called Point 660, which is about 18 miles ENE of Kangerlussuaq on the west coast. The ice is about 2,000 feet thick here. The dark brown color is eons of dust, melted out of the ice sheet. Most of the dust does not wash away with melt because the surface of the ice is exceeding rough. https://goo.gl/maps/EUJZdJS258L2
We have delayed too long and now must urgently reduce the load of warming gases already emitted to our sky. We have been warned this would happen for decades, we just didn’t think it would happen so soon. This is exceedingly bad news, though the good news with climate change is very good indeed. The cost to reset our climate to preindustrial conditions will be no more than what we spend on ensuring safe drinking water every year and the solution will very significantly not be emissions reductions alone.
In April, the National Oceanic and Atmospheric Administration (NOAA) made their latest affirmation of ice sheet collapse at up to 10 feet of sea level rise by 2050 to 2060. Nascent ice sheet modeling has finally begun to approach abrupt sea level rise experienced in paleo history. We are passing through the ice sheet collapse warming threshold, and this is probably the most important and least recognized climate statement our lifetimes (link).
We can hopefully prevent the collapse if we return global temperature to zero degrees warming in a decade or two, but because an ice sheet collapse is a geologic threshold process like an avalanche or rock slide, once we completely cross the tipping point there is no going back. James Hansen, one of if not the single most important climate scientist in the world says; “A sea level rise of 5 meters (16 feet) in a century is about the most extreme in the paleo-record (Fairbanks, 1989; Deschamps et al., 2012), but the assumed 21st century climate forcing is also more rapidly growing than any known natural forcing.”
They say the solutions are too expensive, but expensive is a relative term. How “expensive” will 10 feet of sea level rise by 2050 be?
NOAA Says “Ten Feet of Sea Level Rise by 2050 to 2060”
NOAA is saying up to 10 feet by 2050 to 2060 based on upcoming publishing. Hansen has says that in previous interglacials, 100,000 300,000, 400,000 years ago, when Earth’s temperature was as warm as it is now or within a few degrees of being as warm as it is now, we saw a collapse of the West Antarctic Ice Sheet with rates of sea level rise of up to 16 fete in 100 years, when CO2 was maxed at 280 ppm, not the 400 ppm it is at today. Brand new modeling from Deconto and Pollard say a meter from Antarctica alone, or roughly two meters total by 2100 based on next generation ice modeling that now includes buttressing dynamics, terminal ice face strength, lateral shear, retrograde bed effects, and underice tunneling thermal ocean water convection currents (link). But up until now, modeling has only been able to capture about 4 inches of sea level rise from Antarctica by 2100, so this is a big leap, one that the author suggests is likely still quite conservative based on prehistoric evidence. Blanchon has real evidence of a sea level jump from coral growth rings at Xcaret on the Yucatan Peninsula about 121,000 years ago when Earth’s temperature was about the same as it is today and this evidence shows 6.5 to 10 feet of sea level rise in 10 to 24 years.
The climate science consensus (IPCC and other climate policy work) is based on science that does not include ice sheet collapse. Past ice modeling efforts simply have not had a clue as to how polar ice collapses, the consensus and policy are based on re-creative modeling, and no contribution from dynamic collapse has ever been included in the consensus or policy. Hansen’s work is based on comparing today’s climate with past climates and understanding how past climates have changed sea level. Blanchon’s work is based on real hard evidence (link). And finally, the collapse of the Rhode Island-sized ice shelf the Larsen B, in 2002, took 30 to 40 days (link). Abrupt ice sheet collapse is definitely a thing on our planet when our climate was warming far less than today.
Ice Sheet Collapse Modeling Approaches Reality
So now Deconto and Pollard are approaching real evidence with their modeling. Their modeling is still only 25 percent of what has actually happened in the past with far less CO2 change, but they are light years ahead of where we all were last year this time.
Ten feet of sea level rise will displace 250 million people and the infrastructure submersion, and indirect impacts on hundreds of millions more because of permanent flooding of roads and cities will be a little more obvious than it sounds. Most important however is the submersion of a disproportionate amount of industry along our coastlines. If sea level rise happens faster than about three feet per century total we will not be able to adapt fast enough and this will create economic conditions that words alone are challenged to describe.
So the bottom line is we have no choice. We must somehow rapidly begin to remove carbon dioxide from the atmosphere in the hopes of slowing the irreversible collapse of polar ice that has already begun. Emissions reductions alone cannot do this and in fact, even 80 percent emissions reductions by 2050 allows atmospheric CO2 to continue to rise and global warming to more than double. A rapid reductions of atmospheric CO2 is the only thing that can reduce global warming in time frames that matter and this time frame is likely on the order of a a few decades at the most.
A New Solution to Drawdown Already Emitted CO2
Climate scientists know the perilous state of our climate thank goodness, and they have been feverishly trying to solve the challenges presented by our lack of action of the decades. New research takes one of the solutions of atmospheric carbon dioxide reduction further than previous research.
Normally, rocks play the predominate role in maintaining carbon equilibrium in our atmosphere. They do this by reacting with atmospheric CO2 and neutralizing it, basically changing it to limestone. Taylor et al., have calculated that if we spread a couple of pounds of rock dust per meter across one third of the tropical land mass on Earth it will capture 30 to 300 ppm CO2.
The rates of application they model fall within the range from research in the early 1930s for restoring European forest soils with basalt to encourage tree growth. Mixing depths are a minimum of four inches into the soil with a minimum total area of 7.7 million square miles or about twice the area of the U.S. Specifically, this will cause a reduction of atmospheric CO2 of 140 ppm by 2100 under the RCP4.5 (Stabilization Scenario). This scenario is one that does not make 80 percent emissions reductions but includes significant annual emissions reductions like we find with the Clean Power Plan. With RCP8.5 (Business as Usual Scenario) we can expect atmospheric CO2 to continue to rise to about 590 ppm minimum if we spread a couple of pounds of rock dust per meter across an area twice the size of the U.S.
Costs are $50 to $200 trillion for 50 ppm drawdown of atmospheric CO2, or a $500 billion to $2 trillion per year for 100 years, or $1 to $4 trillion per year for 50 years. We spend a half trillion per year on advertising across the planet every year, so even with these seemingly outrageous costs, this techniques is entirely feasible, except there are technologies far cheaper to achieve 50 ppm CO2 drawdown that do not require tilling an area twice the size of the U.S.
A Better Way to Drawdown Already Emitted Climate Pollution
At $200 per ton, direct air capture (DAC) of CO2 costs $21 trillion for mature WW II era technologies, and at the suggested $20 per ton fully industrialized for new technologies the cost is $2.1 trillion for 50 ppm CO2 (link). Converting the captured CO2 to a stable form, or storing it underground is still required with DAC, but these costs are expected to be less than 20 percent of the capture costs.
CO2 capture using ground rocks as fertilizer:
Taylor et al., Enhanced weathering strategies for stabilizing climate and averting ocean acidification, Nature Climate Change, December 2015.
http://pubs.giss.nasa.gov/abs/ta03100n.html
5 m (16 feet) of sea level rise in a century:
Hansen et al., Ice melt, sea level rise and superstorms…Atmospheric Chemistry and Physics, March 27, 2016.
http://www.atmos-chem-phys.net/16/3761/2016/acp-16-3761-2016.pdf
Blanchon, et al., Rapid sea level rise and reef back stepping at the close of the last interglacial highstand, Nature, April 2009. First Paragraph, page 884: “During those jumps, direct measurement of rise rates shows that they exceeded 36 mm per year.” (1.2 feet per decade)
https://www.academia.edu/196059/Rapid_sea-level_rise_and_reef_back-stepping_at_the_close_of_the_last_interglacial_highstand