Climate InterventionMitigation!Júlíus Sólnes, Professor Emeritus at the Department of Civil and Environmental Engineering, University of Iceland

The Two US National Research Council Reports-2015In 2012 the U.S. government, including several of the science agencies, asked the National Academy of Sciences to provide advice on “Climate Geoengineering” or Climate Intervention.The National Research Council (NRC, a part of the National Academy of Sciences) assembled in response to this request, and established a working group to prepare a report on Carbon Removal Strategies.The two final reports were published 2015 and are available on this website:https://www.nap.edu/catalog/18805/climate-intervention-carbon-dioxide-removal-and-reliable-sequestrationClimate Intervention: Reflecting Sunlight to Cool Earth | The National Academies Press (nap.edu)

Main conclusion 1. We should continue to focus most heavily on reducing greenhouse gas

emissions in combination with adapting to the impacts of climate change because these approaches do not present poorly defined and poorly quantified risks and are at a greater state of technological readiness.

Mitigation, although technologically feasible, has been difficult to achieve. However, it is likely to be absolutely necessary for reducing emissions. The Cap and Trade system, although heavily criticized for its ineffectiveness to curb

emissions, has removed incentives for industrial facilities to apply carbon removal technologies. Buying emission quotas is easier.

Politicians believe that carbon taxes will solve the problem

2: The committee recommends research and development investment to improve methods of carbon dioxide removal and disposal at scales that would have a global impact on reducing greenhouse gas warming, in particular to minimize energy and material consumption, identify and quantify risks, lower costs, and develop reliable sequestration and monitoring.

Human perturbation of the Carbon Cycle

Average, annual rate 2019: 36.44 GtCO2

CDR Methodologies Land Management-Biosequestration

Afforestation, Reforestation, Protection of Existing ForestsCarbon Sequestration on Agricultural Lands

Enhanced WeatheringOcean Fertilization Bioenergy with Carbon Capture and Sequestration

(BECCS)Carbon Capture and Sequestration/Use from industrial

point sources /CCS&U Direct Air Capture of CO2 and Sequestration (DAC)

Biosequestration Biosequestration is the capture and storage of atmospheric carbon dioxide by

biological processes such as photosynthesis Biosequestration in vegetation can be enhanced by genetically modifying the

RuBisCo plant enzyme. Plants use this enzyme in the first step of carbon fixation during the photosynthesis process. Plants with unmodified or the natural enzyme are classified as C3 plants.

Plants with genetically modified RuBisCo enzyme are classified as C4 plants. The modification is called Hatch-Slack pathway. It overcomes the tendency of C3 plants to wastefully fix oxygen together with the CO2.

A new frontier in crop science is the attempt to genetically engineer C3 staple food crops such as wheat, barley, soybeans, potatoes and rice with the turbo-charged photosynthesis capability of C4 plants.

Forests play an important role in the global carbon cycle Living trees are a natural carbon sink, removing CO2 from air, incorporating it into their

tissues as they grow. Dead wood, fallen leaves etc. decomposes and releases CO2 to the atmosphere.

Trees release pure oxygen when they use energy from the sunlight to make glucose from the carbon dioxide absorbed and water. However, they use oxygen when they split the glucose back down to power their metabolism. Still, they release more oxygen than they consume.

Interesting facts about trees A human being breaths about 9.5 tons of air in a year. By mass, oxygen is about 23% of air, and we

extract only about one-third of the oxygen from each breath. This works out as 740 kgs of oxygen inhaled per year.

It takes 6 molecules of CO2 to produce 1 molecule of glucose by photosynthesis, and in the process 6 molecules of O2 are released as a by-product. A glucose molecule (C6H12O6) contains 6 carbon atoms, so we have a net gain 1 molecule of oxygen

released for every atom of carbon added to the tree. A mature sycamore tree, about 12 m tall, weighs 2 tons including roots and leaves. It grows about 5%

every year, and produces 100 kg of wood, 36 kg of which will be carbon. Allowing for the molecular weights of carbon and oxygen this equates to 100 kgs of oxygen released per

year.

Thus it takes 7 to 8 sycamore trees to produce the oxygen a human being requires in one year. Sometimes the great tropical forests are called the lungs of the Earth. This is a misnomer as the function

of the forests is reverse to that of the lungs. Trees “breath” carbon dioxide and “exhale” oxygen. Unfortunately the inhabitants of the Earth are much better at cutting down trees than planting them. Planting new trees to curb climate change will not be enough, but every little thing helps. The tropical forest, the rain forest, is most important in this endeavour. The boreal and northern

temperate forests much less so. In fact, boreal forests have a negative effect due to reduced albedo.

Afforestation and Reforestation(restoration of forest on deforested land >50 yrs ago andrestoration of forest on more recently (<50 yrs) deforested land)

Global reforestation and afforestation has created a carbon sink equivalent to about 1 GtCO2 (2005)

Deforestation is the source of land use GHG emissions that account for about 10% of total anthropogenic GHG emissions from all sources. These emissions are dominated by land use changes due to tropical deforestation (The Rain Forest is decreased by the area of England and Wales combined every year).

The efficiency of removing CO2 from the atmosphere through afforestation and reforestation depends on many factors (age of trees, tree species, plus many more factors). According to IPCC AR5, Boreal forest can sequester up to 1.5 GtCO2/yr

Temperate forest up to 9.5 GtCO2/yr

Tropical forest (the Rain forest) up to 14.0 GtCO2/yr

Global Forest Carbon BudgetThe tropical forests are being reduced by burning and deforestation equivalent to the size of England and Wales every year.

Artificial Trees with artificial but morepowerful built-in photosynthesis units

Carbon sequestration-agricultural landsWetlands restoration

The greatest per-hectare emissions of CO2 from agricultural soils have occurred on cropland created by the drainage of wetlands and the lowering of water tables by installation of drainage systems, often referred to as “tiling” (Fargione et al., 2008). Prior to cultivation, these lands were rich in organic carbon due to anoxic conditions in hydric soils. Both draining and tiling allow oxygen to enter deeper into these soils, greatly increasing the rate at which organic matter is decomposed to carbon dioxide. Smith et al. (2008) note that raising water tables and converting cropland back to wetlands can lead to “rapid accumulation of soil carbon” but may also increase releases of methane, a potent GHG. The mitigation potential of improved water management activities is estimated to be between −0.6 and 3 tCO2-eq/year per hectare (Smith et al., 2007)

Enhanced weathering

Some rocks or minerals are good at trapping carbon dioxide from air

One suggested usage of this fact is to use the mineral olivine, which is plentiful, crush it into fine sand and spread it over land, perhaps along coastlines

Mining, crushing and transporting the billions of tons of olivine needed to make a difference will be very expensive and energy intensive.

The carbon removal will be exceedingly slow.

Ocean Fertilization – a biological pump Planctonic algae and other microscopic plants in the sea absorb CO2 at the

ocean surface and convert it to particulate organic matter.

Some of this matter settles into the deep ocean and serves as food for deepsea organisms. They respire or release CO2 in turn. However, the net result is a positive carbon dioxide sink (sequestering CO2 in the deep ocean).

Approaches have been proposed to increase the strength of this biologicalpump by deliberately adding nutrients to fertilize the ocean plankton.

Due to large ratios of carbon to iron in planktonic organic matter, Ocean Iron Fertilization has been suggested as a viable approach.

Recent studies, however, have identified a number of possible drawbacks toiron fertilization.

Therefore, the NRC committee considers this an immature CDR technology with high technical and environmental risk.

The Ocean-Carbon Dioxide Interchange

Bioenergy with Carbon Capture andStorage (BECCS) BECCS combines the use of bioenergy with geological carbon capture and

storage E.g., timber burned in power plants, and the CO2 captured and stored/used

Excess household and industrial waste, which can‘t be recycled or reused, burned in Waste-to Energy Power Plants (about 500 such plants in the European Union + EFTA countries). 30% barrier. Maximum ~70% of all household and industrial waste can be recycled/reused (see https://www.cewep.eu/).

Produce BIOCHAR. It is a kind of Charcoal created by pyrolysis of biomass Can be used for soil improvement; increases fertility and agricultural productivity

Techniques for producing biochar in low-tech cooking stoves for developing countries that can use agricultural waste, e.g. rice husks

The Capturing and Storage techniques for the CO2 generated by burning of biochar are the same as for fossil fuels

Total waste collected 2016–2018

2018: ~1.3 million tons (about 7% reduction between 2017 and 2018) Composting/biomass 24,000 tons Recycling: 225.000 tons Reusing: 93.000 tonn (incineration with energy production, 1 ton) Minerals, broken concrete etc. for reusing: 720.000 tonn To landfill: 230.000 tons (landfill with and without permit; incineration without

energy production is classified as landfill waste according to EU regulations) Total 1.293.314 tons

2017: ~1.4 million tons. 40% increase between 2016 and 2017 2016: ~1,0 million tons. Total waste exceeded one million tons for the first

time (1.067.318): (26% increase between 2015 and 2016)

Total municipal and industrial waste generated annually in Iceland. Statistics Iceland (Hagstofa Íslands) 2016, 2017 og 2018

Municicpal waste treatment Europe 2018

Iceland (2017)

https://www.cewep.eu/

Amager Bakke in Copenhagen. The flagship of modern waste-to-energy plants in Europe

The station receives ~400,000 tons of waste for incineration annually.It produces enough hot water (~100ºC) to provide space heating of 25,000 apartments in Copen-hagen. Moreover, it produces 30MW of electrical power for the national grid.

Post-combustion type CO2removal system is being implemented, and will be operational 2022.

Carbon Capture and Sequestration/Usage

Monoethanolamine (MEA) strippersA simplifiedVersion of an amine CO2stripper. Just togive an idea of the process. It is very well knownand developed.

Over 100 yearsago, engineershad to install carbon dioxideremoval units insubmarines.

The most common and proven CDR technology

National Carbon Capture Center (NCCC)Wilsonville, Alabama - https://www.nationalcarboncapturecenter.com

The US Department of Energy (DOE) test facility for CCS/U & DAC is operated by the Southern Company in Alabamaþ

The DOE operated a 500 MW coal fired powerplant in Wilsonvillein the early 1990s, which was an experimental unit for developingclean coal power.

The NCCC focuses on pre- and postcombustion carbon removaltechnologies as well as DAC.

The Center collaborates with research centres and universitiesfrom all over the World.

Amine CO2 Stripper

Direct Air Capture of Carbon Dioxide (DAC)Carbon Engineering (photo) has operated a test facility for direct aircapture of CO2 inSquamish, British Columbia for severalyears.

Another engineeringcompany, ClimeWorks, founded by engineersat ETH in Zürich(2007)has a test facilitythere and anothersmaller one at Hellisheiði geothermalpower plant in Iceland

Carbonengineering.com - climeworks.com

The two DAC solutions use heat-drivenfilters to extract the CO2 directly from air

CO2 SequestrationCarbfix is based on the ability of basalticrock to chemically bind CO2.1. CO2 is dissolved in the down stream

liquid (water, seawater), injected into~800 metres boreholes.

2. CO2 +H2O = H2CO33. H2CO3 = HCO3

- + H+

4. (Ca2+, Fe2

+, Mg2+) + HCO3

− = (Ca, Fe, Mg)CO3 + H+

5. The H+ ions are consumed by various dissolution reactions in basalt.

Direct sequestering of CO2 in the deep ocean (1000 – 3000 metres) shown on the figure to the right. The CO2 remains there for more than 100 thousand years.

Finally, CO2 can be sequestered by pumping it down boreholes in depleted oil fields.

Ocean disposal strategies for inorganic processes (i.e., not ocean fertilization). CO2 could potentially be placed in the ocean either as a highly compressed gas (CO2), or dissolved in alkalinity-enriched seawater (CO2/CaCO3). Highly compressed CO2 could be placed on the seafloor or dispersed in plumes. Pipes or ships could be used to transport the CO2. Carbon dioxide and alkalinity-enriched seawater would need to be dispersed in the ocean. SOURCE: IPCC, 2005, Chapter 6 on Ocean Storage

Carbon Removal Technology“Nobody really wants it!”, Lee Lane, 2010

It is like an orphan, whom nobody wants to adopt Industry finds it too costly, wants to buy emission quotas insteadMany right wingers do not believe carbon removal is

necessary, climate engineering is an answer to a bogus problem - climate change is a big hoax

Most left wingers and environmentalists see CCS and DAC as a threat to greenhouse gas controls. Carbon removal is a bogus answer to a crisis that they want to put to better use – e.g., enforcing greener economy, back to nature lifestyle – most importantly stopping fossil fuel usage altogether.

Concluding Remarks If we want to reduce carbon dioxide emissions and try to keep the global average

temperature from rising more than the 2.0ºC set at the Paris conference in 2015, not to mention the 1.5ºC goal, which most scientists say is necessary, we need to seriously address this problem.

Changing our lifestyle in the western developed countries – eating less meat, planting more trees, sorting our garbage better, and using public transportation instead of own cars, will not do the job.

If the Non-OECD world goes about its business as usual, leaving it to the richer OECD countries to fight climate change, the battle is lost.

We need to address the 10 GtC stream from the burning of fossil fuel and cement production. We need the CCS technology to be made available and enforce a global rule that all fossil fuel

burning industries in the entire world are obliged to capture the CO2 from their smokestacks or use oxyfuel systems. We will need to set up global investment funds to help the Non-OECD countries to do this.

Artificial trees with artificial strong photosynthesis units sounds promising. Also, large areas with artificial photosynthesis plants in remote desert-like areas is noteworthy.

Direct Air Capture of CO2 sounds good but requires exorbitant investment and placement of large such facilities to make a difference.