Showing posts with label geo-engineering. Show all posts
Showing posts with label geo-engineering. Show all posts

Tuesday, May 7, 2013

ElectroStatic, NanoCone, Ion Gun, Vortex Separated, Ideal Drop Size, Saltwater Cloud-Cannons

Aaron Franklin
By Aaron Franklin

The apparatus consists of a vertical cylindrical wind-rotor, the interior of which is used as an ideal drop size cloud making machine.
  • The inside surface of the cylindrical wind rotor has metal coated polyester film laminated to it with the metal coated surface facing inwards.
  • The Metal coated Polyester film has been coated with a light sensitive emulsion, photo-exposed in a lattice of dots, and etched to produce an array of nano-cones on the surface of the metal, surounded by a hexagonal lattice of valleys.
  • Spaced by insulators, a few millimeters from the nano-cone surface, is a concentric cylinder of metal mesh. This will probably be silver wire mesh of around 1mm grid spacing and 0.1mm wire gauge.
  • At the centre of the cylinder is a non-rotating, star buttressed spar.
  • The star buttressed spar has microbubble aerated water plumbed through it, to a regularly spaced grid of de-Lavel nozzles, of around 1mm diameter, aiming tangentially at the inside of the rotor, from the outer tips of the star buttress.
  • The water supply aeration is around 50%, with the bubble size controlled to around 0.1mm. This should produce an atomised spray of water droplets around 0.1mm diameter, from the de-Lavel nozzles.
  • The 0.1mm water droplets transfer their energy to rotor rotation, and air vortex motion, in the cylinder of air close to the inner surface of the rotor cylinder.
  • The 0.1mm water droplets pass through the metal mesh, and land on the nanocone surface, producing a thin film of water.
  • A high frequency, high voltage, alternating electric potential is supplied between the nano-cone metal film, and the metal mesh.
  • When the voltage peaks the electric field will cause each Nano-cone to jet a charged micro-droplet of water. The apparatus will be tuned so that these droplets will be around half the ideal size for our perfect clouds.
  • The opposite charge on the metal mesh, will accelerate each charged droplet. The Voltage frequency will be such that the droplet reaches the mesh at the time that the polarity has fully reversed. This will ensure that the droplet passes through the mesh, and is carried by its momentum to the non-rotating airmass at the centre of the rotor.
  • As droplets of alternating polarity are being fired into the rotor-core, each droplet will quickly be attracted to an oppositely charged droplet, combining to form a neutral droplet of the Ideal Size.
  • At the bottom of the rotor cylinder the de Lavels are pointed a little upward to induce a helical input of air-large droplet mixture, entraining and sucking in air from the open bottom of the rotor.
  • The axiswise upward angling of the lower de Lavels reduces the further up the rotor you go, reaching pure tangential before the top. This will create an inwards airflow towards the rotor axis.
At droplet sizes of 8.e-12 litres, 20m rotor 2m diameter = 120sqm of nanocones, nanocone grid spacing 0.2 mm =25 /sqmm= 25 000 000 /sqm = 3 billion, and 5khz electric field....120 litres per second of ideal droplets could be released by this system.
At an average velocity from nanocone to grid of each droplet of 30m/s = 30 000 mm per second... the droplet will travel 3mm in 1/10000 of a second- the time taken for the 5khz field to reverse polarity.  So with these numbers, 3mm gap between the Nanocone surface and the metal mesh seems appropriate.
Tuning will have to allow for evaporative losses from the droplets, however as all the droplets will have the same size and velocity, this should be an easy task.
It may not be necessary at all to use electrostatics. Larger helical angled de Lavels at the bottom of the rotor creating a vortex seperation system where too large droplets impact the inner surface of the rotor, and small enough ones exit at the top may work adequately. A fatter at the bottom, tapered rotor would work well in this case, as it would help expel out the bottom, the waste flow from the too large droplets centrifically.
Star buttresses may not be neccesary on the central spar, particularly with the non-electric version.
Filtering requirements are low, particles smaller than 0.1mm should cause no problems for the electro version, smaller than 1mm no probs at all for the pure vortex model.

Tuesday, March 5, 2013

Supersonic and high velocity Subsonic Saltwater and Freshwater Cloud Making Cannons

Aaron Franklin
By Aaron Franklin

As a compliment to cloud brightening systems, these for use in calm blue sky conditions, or windy blue sky conditions, over Ocean, sea and glacial ice, and land permafrost.

Also may be very important this year for as high tech cloud brightening/making doesn't look like it will be easy to get out in large unit numbers, while there is existing firepump systems that are available in numbers we need now.

Also are essentially no different from snowmaking gear used on ski fields, except for making snow, lower velocity is fine, and no CCN's are required. Just air below 0C, and freshwater.

- High pressure / high volume fire-fighting/water cannon pump gear can be used as is, or modified for higher pressure and kW capacities to increase output volumes at similar nozzle velocities.

An aerated system looks best at this point because:
  • By using de Laval nozzles ( convergent-divergent, supersonic and tight stream output ) the aerated water can be accelerated by expansion to high velocity or Supersonic speed as it leaves the divergent exit section of the nozzle.
  • Nozzle friction is reduced because air sticks to the surface and creates a gaseous boundary layer.
  • For Aeration, copper or soft stainless tubes CNC laser perforated, swaged to flare to hexagonal ends, stacked for a honeycomb aeration section (just like a ww2 spitfire radiator except they had the water on the outside of the tubes and no holes) fed with compressed air, in the water feed before the pumps can entrain microbubbles in the water. 
  • Alternatively supersonic streams can be achieved with unaerated water with convergent nozzles, but more pressure is required.
  • The high kinetic energy of the water stream will cause excellent dispersion, and evaporation, via transonic shockwaves as the stream slows, shedding its outer layer as it goes, eventually disintegrating completely either below the altitude where enough kinetic energy, has converted to gravitational potential energy for the stream to go transonic if the stream is below a critical diameter, or not far above that altitude if its above that diameter.
  • If its a high velocity Subsonic jet it will still shatter the droplets and evaporate lots of, if not all of them by air turbulence and high differential speed energy conduction/friction evaporation.
  • We need to look at freshwater versions as well. This because saltwater rain will be fine over open oceans but it landing on ice and land permafrost will make them melt faster. And saltwater rain on land living ecologies is not at all good either. There's going to be a big use for them to protect the land permafrosts with cloud cover too. Freshwater versions will benefit from using water with diatoms growing in it, as these act as cloud droplet condensation nuclei, just like salt crystals.

    Seeding tundra lakes with diatoms will also eat CO2, oxygenate the water enhancing aerobic digestion of dissolved methane and other organic carbon. Removing the diatoms with the water for cloud cannons will also remove excess nutrients from the waters, provide aeration for skyborne digestion of DOC to CO2, and will clean up lakes to make them better for winter snow-making watersources.
  • We're going to need to straffe the sky with these things for best cloudmaking effect, so we need to get ready to mount them on naval gun turrets with computer controlled tracking systems and look into parking tanks and APC's with suitable turrets on container ship decks.

    Using these tanks and APC's, maybe fixed installations when the wind is blowing, with cloud-cannons on the arctic tundras can help protect the permafrosts. 

Calculations and conclusions, for peer review:

These are based on a sonic speed case. Faster will give more range but less volume and slower more volume but less range, for a given pump system.

speed of sound 330m/s

Ep= mgh

Ek= 0.5mv^2

Ek sonic (1 kg water)= 0.5 x 1 x 330^2 = 54450J

54450=mgh=1 x 9.8m/s^2 x h

vertical ballistic altitude h=54450/9.8 = 5.556km


cloud water content = 0.3g/m^3

10m thickness= 3g/m^2

100m thickness= 30g/m^2

4 sqkm= 4,000,000 m^2


Fixed position still air straffing:

A=pi.r^2

r=sqrt(A/pi)


4 sqkm horizontal Cannon range r = sqrt(4/pi)= 1.12km


Moving ship, land tanker, or wind blowing fixed position straffing:

14m/s = 50km/hr (vehicle or wind velocity)

-4 sqkm per hr requires only 4/50= 80m watercannon range.


Water volume and flow rates:

4sqkm at 10m thick= 12000 liters= 12 tons (less than 10min with flow rates of existing fire pumps)

at 100m thick = 120 tons (could be less than an hour per firepump)

1 small Supersonic cloud cannon could produce 24hr x 4sqkm/hr = 96sqkm of 100m thick cloud per day.


Kinetic energy:

120,000 liters per hr / 3600 = 33.3 L/s

12,000 liters per hr / 3600 = 3.3 L/s

Ek Sonic 1kg = 54.45 kJ


kW 100m thick, 4sqkm cloud layer in an hr = 33.3 L/s x 54.45kJ = 1813 kW

- existing pump designs would need to be upgraded for higher power/pressure to produce this much cloud, if supersonic velocities are required, but this is a very small engineering challenge. Ships trawler size and up, and tanks have more than enough kWs for the job. Rapid small amplitude vertical oscillation of the jet release angle should lay down the average 100m thick cloud bank aimed for.

kW 10m thick, 4sqkm cloud layer in an hr = 3.3 L/s x 54.45kJ = 181.3 kW

- this looks good for mobile straffing with existing fire pumps, provided aerated water and deLavel nozzles are used to produce supersonic velocities. The range required for 4 sqkm per hr coverage at only 80m is no problem for the small volume, aerated supersonic water flows possible from existing fire pumps.


Latent heat of evaporation and Ek sonic considerations:

latent heat of evaporation water = 2260 kJ per L

Ek sonic water = 54.45 kJ per L

  • If the very small water droplets produced by transonic shockwaves shattering any water breaking from the decaying jet should partially or fully evaporate (this will depend on stream velocity) they will be doing this by absorbing a lot of heat from the air they are landing in. This will cool and supersaturate the air with water vapour, and result in rapid droplet condensation in both saltwater and freshwater versions proposed.
  • I am advised that we can expect around 60% humidity levels in arctic conditions. As the evaporative cooling effect will cool the air that the stream droplets land in, and vast quantities of very small cloud nucleation salt crystals will be formed, we can expect a lot more cloud to be formed than the above examples suggest.
  • Aeration should result in more and smaller salt crystals, and droplets. In part due to microbubbles enhancing droplet fragmentation. Also due to supersaturation of the water with air, enhanced by evaporation. This causing many disturbances per drop as new bubbles precipitate, and initiate many salt crystals per droplet to precipitate. Turbulence will also initiate precipitation of air and salt crystals in the supersaturated droplet.
  • How much extra cloud will depend on how much atmosperic turbulence and mixing is generated by the straffing pattern, and on local temperature and humidity conditions.
  • Less mixing will also result in larger cloud droplets.
  • Too much mixing will run the risk of forming little cloud at all, as the humidity levels may be too low to form any droplets at all around the salt crystals.
  • It's quite likely that 500-600kph will be sufficient velocity. This would produce about 15 litres per second from standard firepump gear. A good estimate seems to be that this would initially produce around 100sqkm of 100m thick cloud bank per day. However from what I am hearing there is likely to be a repeating cycle of droplet evaporation - re nucleation of new droplets - back to droplet evaporation, due to the added water vapour and downwind cooling effects. So total cloud produced may be more than this.
  • We should start testing on these ASAP. Others doing testing too, would be a good thing.

Saturday, January 5, 2013

How to avoid mass-scale death, destruction and extinction

Climate change threatens to develops in four ways:
  1. Global warming
  2. Accelerated warming in the Arctic
  3. Runaway global warming
  4. Extinction
Warming accelerates in the Arctic due to a number of feedbacks, ten of which are depicted in the Diagram of Doom.

One of these feedbacks, methane releases from the Arctic seabed, constitutes a point-of-no-return, in that this threatens to trigger further releases in a vicious cycle that will escalate into runaway global warming. The combined impact of land degradation, storms and heatwaves will then cause crop and vegetation loss at unprecedented scale, resulting in mass death, destruction and extinction.

High food prices have been around for a few years, as illustrated by the FAO Food Price Index below (see interactive version of this image).



The FAO, in its recent Cereal Supply and Demand Brief, explains that we can expect prices to rise, as illustrated below.


The Economic Research Service of the U.S. Department of Agriculture mentions, in its Food Price Outlook, 2012-2013, that the "drought has affected prices for corn and soybeans as well as other field crops which should, in turn, drive up retail food prices".

Global food supply is under stress as extreme weather becomes the new norm. Farmers may be inclined to respond to drought by overusing ground water, or by slashing and burning forest, in efforts to create more farmland. Such practices do not resolve the problems; instead, they tend to exacerbate the problems over time, making things progressively worse.

The diagram below shows that there are many climatological feedbacks (ten of which are named) that make climate change worse. At the top, the diagram pictures vicious cycles that are responses by farmers that can add to make the situation even worse. Without effective action, the prospect is that climate change and crop failure combine to cause mass death and destruction, with extinction becoming the fourth development of global warming.

How can we avoid that such a scenario will eventuate? Obviously, once we are in the fourth development, i.e. mass-scale famine and extintion, it will be too late for action. Similarly, if the world moves into the third development, i.e. runaway global warming, it will be hard, if not impossible to reverse such a development. Even if we act now, it will be hard to reverse the second development, i.e. accelerated warming in the Arctic.

The most effective action will target causes rather than symptoms of these developments.

Part 1. Since emissions are the cause of global warming, dramatic cuts in emissions should be included in the first part of the responses. In addition, action is needed to remove excess carbon dioxide from the atmosphere and oceans. Storing the carbon in the soil will also improve soil quality, as indicated by the long green arrow on the left.

Part 2. Solar radiation management is needed to cool the Arctic.

Part 3. Methane management and further action is needed, e.g. to avoid that methane levels will rise further in the Arctic, which threatens to trigger further releases and escalate into runaway global warming. Measures to reduce methane can also benefit soil quality worldwide, as indicated by the long green arrow on the right.

Thus, the proposed action tackles the prospect of mass death and extinction by increasing soil fertility, as illustrated by the image below.


Depicted at the bottom of the image are the most effective policies to accomplish the goals set out in the proposed 3-part plan of action, i.e. feebates, preferably implemented locally. Cost associated with solar radiation management is relatively small, so relatively small fees, e.g. on commercial international flights could raise the necessary funding.

Thursday, November 29, 2012

A Comprehensive Plan of Action on Climate Change


Threat to global food supply makes comprehensive action imperative
Climate change is strongly affecting the Arctic and the resulting changes to the polar vortex and jet stream are in turn contributing to extreme weather in many places, followed by crop loss at a huge scale.

The U.N. Food and Agriculture Organization (FAO) said in a September 6, 2012, forecast that continued deterioration of cereal crop prospects over the past two months, due to unfavourable weather conditions in a number of major producing regions, has led to a sharp cut in FAO’s world production forecast since the previous report in July.

The bad news continues: Based on the latest indications, global cereal production would not be sufficient to cover fully the expected utilization in the 2012/13 marketing season, pointing to a larger drawdown of global cereal stocks than earlier anticipated. Among the major cereals, maize and wheat were the most affected by the worsening of weather conditions.

The image below is interactive at the original post and shows the FAO Food Price Index (Cereals), up to and including August 2012.

from: Threat to global food supply makes comprehensive action imperative
Apart from crop yield, extreme weather is also affecting soils in various ways. Sustained drought can cause soils to lose much of their vegetation, making them more exposed to erosion by wind, while the occasional storms, flooding and torrential rain further contribute to erosion. Higher areas, such as hills, will be particularly vulnerable, but even in valleys a lack of trees and excessive irrigation can cause the water table to rise, bringing salt to the surface.

Fish are also under threat, in part due to ocean acidification. Of the carbon dioxide we're releasing into the atmosphere, about a third is (still) being absorbed by the oceans. Dr. Richard Feely, from NOAA’s Pacific Marine Environmental Laboratory, explains that this has caused, over the last 200 years or so, about a 30% increase in the overall acidity of the oceans. This affects species that depend on a shell to survive. Studies by Baumann (2011) and Frommel (2011) indicate further that fish, in their egg and larval life stages, are seriously threatened by ocean acidification. This, in addition to warming seawater, overfishing, pollution and eutrification (dead zones), causes fish to lose habitat and is threatening major fish stock collapse.

Without action, this situation can only be expected to deteriorate further, while ocean acidification is irreversible on timescales of at least tens of thousands of years. This means that, to save many marine species from extinction, geoengineering must be accepted as an essential part of the much-needed comprehensive plan of action.

Similarly, Arctic waters will continue to be exposed to warm water, causing further sea ice decline unless comprehensive action is taken that includes geoengineering methods to cool the Arctic. The threat that huge amounts of methane will be released from the warming Arctic seabed makes it imperative to prepare geo-engineering methods to respond to this threat and be ready for rapid deployment soon.

How to avert an intensifying food crisis

As extreme weather intensifies, the food crisis intensifies. Storms and floods do damage to crops and cause erosion of fertile topsoil, in turn causing further crop loss. Similarly, heatwaves, storms and wildfires do damage to crops and cause topsoil to be blown away, thus also causing erosion and further crop loss. Furthermore, they cause soot, dust and volitale organic compounds to settle on snow and ice, causing albdeo loss and further decline of snow and ice cover.

Extreme weather intensifies as the Arctic warms and the polar vortex and jet stream weaken, which is fueled by accelerated warming in the Arctic. There are at least ten feedbacks that contribute to further acceleration of warming in the Arctic and without action the situation looks set to spiral away into runaway global warming, as illustrated by the image below.

Diagram of Doom, with Comprehensive Plan of Action added  (credit: Sam Carana, October 9, 2012)



To avert an intensifying global food crisis, a comprehensive plan of action is needed, as also indicated on the image. Such a plan should be comprehensive and consider action in the Arctic such as wetland management, ice thickening and methane management (methane removal through decomposition, capture and possibly extraction).

A Comprehensive Plan of Action on Climate Change

A Comprehensive Plan of Action on Climate Change needs to include policies to achieve a sustainable economy, as well as adaptation policies.

Such a comprehensive plan is best endorsed globally, e.g. through an international agreement building on the Kyoto Protocol and the Montreal Accord. At the same time, the specific policies are best decided and implemented locally, e.g. by insisting that each nation reduces its CO2 emissions by a set annual percentage, and additionally removes a set annual amount of CO2 from the atmosphere and the oceans, followed by sequestration, proportionally to its current emissions.

Policy goals are most effectively achieved when policies are implemented locally and independently, with separate policies each addressing a specific shift that is needed in order to reach agreed targets. Each nation can work out what policies best fit their circumstances, as long as they each independently achieve agreed targets.

Cuts in CO2 emissions of 80% by 2020 can be achieved by implementing local policies focusing on specific sectors (such as energy production, transport, land use, waste, forestry, buildings, etc).

As an example, each nation could add fees on jetfuel. Where an airplane lands that comes from a nation that has failed to add sufficient fees, the nation where the airplane lands could impose supplementary fees and use the revenues to support methods that capture CO2 directly from ambient air. Such supplementary fees should be allowed to be imposed under international trade rules.

Some policies will need to continue beyond 2020, in order to bring down levels of greenhouse gases in the atmosphere to their pre-industrial levels this century, i.e. getting CO2 in the atmosphere back to 280ppm, CH4 back to 700ppb and N2O back to 270ppb. Policies can be very effective when focusing on local sectors such as agriculture and buildings, while also supporting geo-engineering methods such as biochar, enhanced weathering and direct capture of carbon from ambient air.

In addition to such policies to achieve a sustainable economy and adaptation policies, further geo-engineering methods will be needed to avoid runaway warming, as indicated in the blue area of the image below.


Arctic Methane Management

At the original post, some of the areas in these images can be clicked on, for examples or more background. The box for Additional Arctic Methane Management on above image is further worked out in the image below, which highlights the need for geo-engineering methods that focus on methane, a component of the plan that needs to be given far more attention. Again, support for such methods could be agreed to proportionally to each nation's current emissions.

Saturday, April 21, 2012

Discussion: Should patent law apply to geo-engineering?


UPDATE:  The Stratospheric Particle Injection for Climate Engineering (SPICE) project has cancelled its outdoor ‘1km testbed’ experiment. 

Nature News - 15 May 2012 - by Daniel Cressey
Geoengineering experiment cancelled amid patent row.
Balloon-based ‘testbed’ for climate-change mitigation abandoned
http://www.nature.com/news/geoengineering-experiment-cancelled-amid-patent-row-1.10645



David Keith, a Harvard University professor and an adviser on energy to Microsoft founder Bill Gates, said he and his colleagues are researching whether the federal government could ban patents in the field of solar radiation, according to a report in Scientific American.

Some of his colleagues last week traveled to Washington, D.C., where they discussed whether the U.S. Patent Office could ban patents on the technology, Keith said.

"We think it's very dangerous for these solar radiation technologies, it's dangerous to have it be privatized," Keith said. "The core technologies need to be public domain."
As suggested by Sam Carana, a declaration of emergency, as called for by the Arctic Methane Emergency Group (AMEG), could be another way to deal with this issue.

A declaration of Emergency could give governments the power to overrule patents, where they stand in the way of fast-tracking geo-engineering projects proposed under emergency rules.Thus, patents don't need to be banned, prohibited or taken away; instead, patents will continue to apply in all situations other than the emergency situation, while new patents could also continue to be lodged during the emergency period.
Even where patents are directly applicable to proposed projects, patent law would still continue to apply; the emergency rules would merely allow governments to proceed in specific situations, avoiding that projects are being held up by legal action, exorbitant prices or withholding of crucial information.

A declaration of emergency could also speed up projects by removing the need to comply with all kinds of time-consuming bureaucratic procedures, such as the need to get formal approvals and permits from various departments, etc. This brings us to the need to comply with international protocols and agreements. If declared internationally, a declaration of emergency could overrule parts of such agreements where they pose unacceptable delays and cannot be resolved through diplomacy.


The issue is also discussed here and here at the Geoengineering group at Google.

Friday, February 10, 2012

January 2012 shows record levels of methane in the Arctic

In January 2012, methane levels in the Arctic reached levels of 1870 ppb. 


Particularly worrying is that, in the past, methane concentrations have fluctuated up and down in line with the seasons. Over the past seven months, however, methane has shown steady growth in the Arctic. Such a long continuous period of growth is unprecedented, the more so as it takes place in winter, when vegetation growth and algae bloom is minimal. The most obvious conclusion is that the methane is venting from hydrates. 

Thursday, September 22, 2011

Carbon-negative technologies


The image below, adapted from Negative Emissions Technologies report by Duncan McLaren (version 2, 2011), pictures a number of carbon dioxide removal (CDR) methods. 





For further discussion of biomass use, see the post Biomass; for further discussion of policy issues, see The way back to 280 ppm and Towards a Sustainable Economy


Wednesday, December 31, 2008

Considerations for New Year

Many of the graphs relating to global warming are exponential, rather than linear. The amount of carbon dioxide in the atmosphere is rising at accelerating speed, unlike anything that has been seen in history. This in itself is sufficient reason for alarm. 

Additionally, there are scenarios in which the combination of several tipping points can lead to a runaway greenhouse gas effect that feeds on itself through positive feedback mechanisms. For an example, read about the Clathrate Gun Hypothesis. For decades, people have warned about this. 

Back in the early 1990s, a poll of the world's leading climatologists showed that many feared that the greenhouse effect could be unstoppable if emissions of polluting gases were merely frozen and not cut. In December 1991, Greenpeace asked 400 climate scientists if they thought the greenhouse effect might reach the point of no return in the near future. Of the 113 scientists who returned their questionnaires, almost half thought a runaway greenhouse effect is possible, and 13 per cent thought it probable. 

James Hansen, who heads the NASA Goddard Institute for Space Studies, recently said that human activity is causing greenhouse gas levels to rise so rapidly that his model suggests there is a risk of a runaway greenhouse effect, ultimately resulting in the loss of oceans and of all life on the planet:
"In my opinion, if we burn all the coal, there is a good chance that we will initiate the runaway greenhouse effect. If we also burn the tar sands and tar shale (a.k.a. oil shale), I think it is a dead certainty." I discussed this danger in the article Venus' runaway greenhouse effect a warning for Earth, originally posted and discussed at Gather

Even if the risk of such scenarios occurring on Earth were small, it makes sense to do the following:
  • describe risk and estimate chances of manifestation, timelines, etc.
  • identify tipping points, feedback mechanisms and give estimate ranges of their combined impact
  • investigate ways to avoid it, mitigate it, etc.
  • conduct comparative analysis of the various proposals
  • make recommendations
What evaluation criteria can be used in above comparative analysis? Here are some suggestions: 

SCIENCE 
Existing studies - Are relevant studies available? Has there been any peer-review? 
Further study - What further studies and modeling are required? 
Effectiveness - How effective will the proposal be in reducing global warming? 
Timescale - How long will it take to see results? 
Concerns - What are possible climate risks, side-effects, dangers? 

ENGINEERING 
Methods - How can it be done? Have specific methods been proposed? 
Technical problems - Could the project run into technical problems? 
Technologies - Does the project require development of new technologies? 
Testing - Has any testing been done? At what scale? 

ECONOMICS 
Cost - Are there estimates as to what (each of the various stages of) implementations would cost? Financing - How could the project be financed? Is there any backing for the project? 
Resources - Will there be access to the various resources needed to make it work? 
Impact - What will be the economic impact? Who will profit from the project? 

POLITICS 
Approval - What kind of approvals are needed to go ahead? 
Subsidies - Are subsidies required for impact studies, feasibility studies or for specific parts of the project? 
Policy - How does the project fit in with specific policies, e.g. offset policies, emissions trading or feebates? 
Legal - Does it require new laws or amendment of existing laws? Can legal challenges be expected? Diplomacy - Would the project require international negotiations between nations? 
Administration - From where will the project be administered? 

SOCIAL AND MEDICAL 
Support - Is there public support for, concern about or resistance against the project? 
Consultation - Who will benefit, who could be harmed? Has the public been consulted? 
Control - What level of policing, supervision and security is needed? What monitoring is needed? 
Medical - Would the project pose safety and health concerns? 
Cultural - Does the project offend some people in some way? 

ENVIRONMENT 
Impact study - Has an environmental impact assessment been done? Are further studies required? 
Maintenance - Is any monitoring, maintenance or restoration required, to prevent environmental damage? 

The above points could give some indication as to how hard it will be to implement a proposed project. Projects could be scored on each point by asking whether this point will raise any difficulties for the respective project. A high score would indicate that little or no difficulty on this point can be expected for the project, while a low score would indicate that the project can be expected to have difficulty on this point. Each point could be given a specific weighting, resulting in overall score for each of the projects. The higher the overall score, the more the project should be of interest to members of this group. A high overall score should indicate that there is sufficient confidence that the project is safe, effective, feasible, viable, etc, with little or no concern, risk or danger that things could go wrong or that a proposal could cause damage or harm in some way. 

Importantly however, this should not be seen as a race where only one winner is selected. It is prudent to encourage diversity in approach and to continue to study multiple ideas and suggestions in parallel. I encourage others to suggest additions and changes to this post. Cheers! Sam Carana "We all hope that things will turn out right, but we must think about what to do, in case it doesn't!" 

Links: 

Clathrate Gun Hypothesis - Wikipedia 

Runaway greenhouse warming 'cannot be rule out' - by STEPHANIE PAIN - February 15, 1992 http://www.newscientist.com/article/mg13318081.600 

NASA scientist warns of runaway global warming - New Scientist - December 22, 2008 

Venus' runaway greenhouse effect a warning for Earth - by Sam Carana - November 28, 2007 

Ranking the ideas - post by Sam Carana, December 27, 2008 http://groups.google.com/group/geoengineering/msg/751aa59e3cc5e8ff 

A naive question - post by Sam Carana, December 31, 2008 

Tuesday, November 4, 2008

Inventory of geo-engineering proposals

Geo-engineering proposals seeking to combat global warming should be assessed according to efficacy, cost, risk, timeframe and the rate at which they can mitigate climate change, says Philip W. Boyd of New Zealand's NIWA in an article published in Nature Geoscience

We need more thought on whether proposals like carbon burial, geochemical carbon capture, atmospheric carbon capture, ocean fertilization, cloud manipulation, space sunshades, or strategically-placed pollution can be effective on a time-scale relevant to humankind, economical, or even safe. 

Meanwhile, AP reports that John Shepherd will head a working group at Britain's Royal Society to study geo-engineering proposals, with a report expected to be published in mid-2009.

Thursday, October 25, 2007

Combat Global Warming with Evaporative Cooling

Combat Global Warming with Evaporative Cooling - by Sam Carana

To combat global warming, wind turbines along the coastline could be used for the dual purposes of generating electricity at times when there is wind and evaporating water at times when there is no wind. Just a small breeze over the water can give the top water molecules enough kinetic energy to overcome their mutual attraction, resulting in evaporation of water and associated cooling of both water and air.

Such dual use of wind turbines can be implemented at many places where turbines overlook water; evaporation will work most effectively in hot and dry areas, such as where deserts or dry areas meet the sea or lakes. Evaporative cooling will add humidity to the air, which can also cause some extra rain and thus increase fertility of such dry areas as a beneficial side effect.

The energy needed to run the turbines can be obtained and stored in a number of clean, safe and renewable ways. ]

At times when there is plenty of wind, surplus energy from the turbines could be used to convert Water into hydrogen by means of electrolysis. Alternatively, bio-waste could be burned by means of pyrolysis to create both hydrogen and agrichar, which could be used to enrich soils. The hydrogen could be kept stored either in either compressed or liquid form, ready to power fuel cells that can drive the turbines at any time, day or night.

Another alternative is to run the turbines on electricity from concentrated solar thermal power plants in the desert. A desert area of 254 km² would theoretically suffice to meet the entire 2004 global demand for electricity. Ausra offers a solar thermal technology that uses the sun's heat to generate steam, which can then be stored for up to 20 hours, thus providing electricity on demand, day and night. Ausra points out that just 92 square miles of solar thermal power facilities could provide enough electricity to satisfy all current US demand.

Finally, there are some environmental concerns about wind turbines. There are concerns about carbon dioxide being released into the atmosphere in the process of making the concrete for the turbines. To overcome this, turbines could be made using alternative manufacturing processes, which can be carbon-negative. Furthermore, a recently completed Danish study using infrared monitoring found that seabirds steer clear of offshore wind turbines and are remarkably adept at avoiding the rotors.

In conclusion, wind turbines have a tremendous potential. They can potentially generate 72 TW, or over fifteen times the world's current energy use and 40 times the world's current electricity use. Offshore and near-shore turbines can make seawater evaporate and thus cool the planet, at times when they are not used to generate electricity.


References:


Ausra
http://ausra.com/

Wind power - Wikipedia 

Thursday, October 11, 2007

Pipes in the oceans to pump up water

Science Museum head Chris Rapley and Gaia theorist James Lovelock are suggesting to install flotillas of vertical pipes in the tropical seas. Free-floating or tethered vertical pipes could pump up nutrient-rich waters from below the thermocline in order to mix them with the relatively barren waters at the ocean surface.

Such pipes could be 100 to 200 metres long, 10 metres in diameter and with a one-way flap valve at the lower end in order to pump water upwards powered by by wave movement. The water pumped up this way could fertilize algae in the surface waters and stimulate them to bloom. More specifically, pumping up water through such pipes would result in an increased presence in the surface waters of the salp, a tiny tube-like species that excretes carbon in its solid faecal pellets. This carbon would subsequently descend to the ocean floor. The hope is that this could store carbon away for millennia on the ocean floor. 

An additional effect would be that the algae produced an abundance of dimethyl sulphide (DMS), a chemical that acts as the precursor of nuclei that form sunlight-reflecting clouds. As more clouds would form above the ocean, more sunlight would be reflected away from the Earth's surface, resulting in relative cooling of the ocean underneath. 

US company Atmocean has in fact already started trials with this type of technology, using pipes that bring cold water to the surface from a depth of 200m. 

References: 

- Mixing the oceans proposed to reduce global warming 

- Ocean pipes could help the Earth to cure itself 

- Lovelock urges ocean climate fix 

Monday, May 7, 2007

Sulphur into the stratosphere

Some are considering releasing dust particles in the air to reflect some of the sunlight, as an alternative to positioning mirrors in orbit above Earth. [There are] a few problems with the dust-particles approach, such as difficulties in regulating the right amount of dust. It may turn out that - in hindsight - too many dust-particles have been released in the atmosphere and that it will be quite a problem getting them out again. Another problem is that the dust-particles method will affect the climate everywhere on Earth.

Sam Carana 
- May 20 2005 

One such proposal is by Paul Crutzen, who won the Nobel Prize for chemistry when he discovered the causes of the hole in the ozone layer. Paul proposes to shoot hundreds of rockets loaded with tons of sulphur into the stratosphere to create a vast, but very thin sunscreen of sulphur around the earth. 

The proposal was discussed in the BBC documentary: 


Mirrors in Space

The concept Mirrors in Space was discussed in an article from the summer 2001 Whole Earth Review, Mirrors & Smoke: Ameliorating Climate Change with Giant Solar Sails, by Kenneth I. Roy, PE and Robert Kennedy, PE.

Over the years, the concept has been discussed in many posts, including in the geo-engineering group by Sam Carana

The ABC show, Good Morning America, on January 29, 2007, featured a clip on mirrors in space, featuring a proposal by Roger Angel, University of Arizona, to send many small discs into space to form giant mirrors deflecting some of the sunlight from Earth.



Roger Angel's research into the feasibility of cooling the Earth with a cloud of small spacecraft near the inner Lagrange point (L1) has been discussed at:
National Academy of Sciences
National Institues of Health

Sciencenews.org
Roland Piquepaille