Scaling and testing geoengineering

There were some meetings and papers considering how to scale and test geoengineering. The papers did not consider iron sequesteration in the ocean. The 120 ton experiment of placing iron sulphate in the ocean was an Eddy scale experiment off of the coast of British Columbia Canada.

Ocean mesoscale Eddies are 10 to 500 kilometers across. (6 to 300 miles)

About two ago ago, an ocean fertilization test, fertilizing around 120 tonnes of iron sulphate off Canada’s coast. Satellite images confirmed the claim by the Haida Salmon Restoration Corporation that the iron spawned an artificial plankton bloom as large as 10,000 square kilometers. Now it appears that the fish catch in the area was boosted by over 100,000 tons. Pink salmon mature in two years. Salmon can add a pound a month if they are well fed in the ocean. 2013 had the largest pink salmon run in 50 years.

The Alaska Department of Fish and Game (ADF&G) has completed compilation of preliminary values for the 2013 commercial salmon fishery. Powered by a record pink salmon harvest of 219 million fish, this year’s harvest ranks as the second most valuable on record. At $691.1 million, 2013 is only exceeded by the 1988 harvest value of $724 million. In addition to setting a record for pink salmon, the total number of salmon harvested also set a new record at 272 million fish. There should be many more of these iron sulphate experiments at Eddy scale. They boost the amount of fish in the ocean. Human action is reducing the levels of iron in the ocean so this work restores those levels.

There also should be more focus on deep ocean science. The ocean covers most of the earth and has a larger impact on the climate and ecosystem than than the land. Atmospheric tests are also important but the ocean needs more scientific focus. There is not enough money invested in studying the deep ocean. Currently it has mainly been rare studies that hitch along with ocean going vessels.

Other geoengineering roadmaps and study summary

There is a summary of a portfolio of possible field experiments on solar radiation management (SRM) [geoengineering] and related technologies. The portfolio is intended to support analysis of potential field research related to SRM including discussions about the overall merit and risk of such research as well as mechanisms for governing such research and assessments of observational needs. The proposals were generated with contributions from leading researchers at a workshop held in March 2014 at which the proposals were critically reviewed.

The proposed research dealt with three major classes of SRM proposals:
1. marine cloud brightening
2. stratospheric aerosols
3. cirrus cloud manipulation.

The proposals are summarized here along with an analysis exploring variables such as space and time scale, risk and radiative forcing. Possible gaps, biases and cross-cutting considerations are discussed. Finally, suggestions for plausible next steps in the development of a systematic research programme are presented.

Mapping of experiment types and classes of models (red lines) to physical scales illustrates the breadth and complexity of solar geoengineering research. No single model or experiment can bridge the gap from smallest to largest scale. For example, microphysical models describe aerosol processes at scales of nanometres and cloud drops and ice crystals at micrometre to millimetre scale. Clouds (ranging from 10 to 1000 m) are addressed by large eddy simulation models and more generally by cloud resolving models. Mesoscale models and general circulation models (GCMs) have similar physics, but mesoscale models can be nested to provide high-resolution simulations that cannot be matched by GCMs. Chemistry can be built into dynamic models (typically mesoscale models and GCMs) or simulated in off-line chemical-transport models. The different types of field experiments, particularly process studies, scaling tests and climate response tests could bridge gaps between scales reducing the uncertainty of large-scale predictions of the risks and efficacy of SRM.

Another paper looks at geoengineering the stratosphere in a controlled experiment.

Stratospheric controlled perturbation experiment: a small-scale experiment to improve understanding of the risks of solar geoengineering

Although solar radiation management (SRM) through stratospheric aerosol methods has the potential to mitigate impacts of climate change, our current knowledge of stratospheric processes suggests that these methods may entail significant risks. In addition to the risks associated with current knowledge, the possibility of ‘unknown unknowns’ exists that could significantly alter the risk assessment relative to our current understanding. While laboratory experimentation can improve the current state of knowledge and atmospheric models can assess large-scale climate response, they cannot capture possible unknown chemistry or represent the full range of interactive atmospheric chemical physics. Small-scale, in situ experimentation under well-regulated circumstances can begin to remove some of these uncertainties. This experiment—provisionally titled the stratospheric controlled perturbation experiment—is under development and will only proceed with transparent and predominantly governmental funding and independent risk assessment. We describe the scientific and technical foundation for performing, under external oversight, small-scale experiments to quantify the risks posed by SRM to activation of halogen species and subsequent erosion of stratospheric ozone. The paper’s scope includes selection of the measurement platform, relevant aspects of stratospheric meteorology, operational considerations and instrument design and engineering.

The StratoCruiser propulsion module (a) contains the docking enclosure for the suspended payload, the articulated solar panels for power, Li–Po batteries for energy storage, dual high-efficiency propellers for concerted directional control, the winching system for suspended payload reeldown as well as all electronics support and command/control requirements. A cutaway of the suspended payload (b) shows representative in situ instruments and their associated inlet systems, meteorological measurements, electronics support, communication command and control, and safety parachute. The configuration of sensors for SCoPEx will be finalized in future engineering studies.

The concept of operations for the proposed experiment is initiated by seeding a 1 km length of stratospheric air with a combination of water vapour and sulfate aerosol using the propulsive capability of the StratoCruiser (a). Using a combination of its altitude and propulsive capabilities, the StratoCruiser manoeuvres past and above the seeded volume, which continues to expand owing to the turbulent wake generated by the propellers. The suspended instrument payload is reeled through the seeded volume to measure aerosols, water vapour and chemical species including HCl and ClO (b). The propulsion capability together with the LIDAR surveillance is used to track the seeded volume as it drifts with ambient wind and to make repeated measurements with the suspended payload, resolving the chemical evolution within the seeded volume as a function of time (c).

The enhanced capabilities of the stage two StratoCruiser system over stage one architecture substantially reduce the risk of failing to obtain a viable experimental operating window and increase the scientific returns, including but not limited to:

— the augmented drive capability allows safe operation during times of year of higher stratospheric winds beyond the short turnaround periods in late spring and early autumn. By expanding the operational window to include June–August, the probability of gaining a launch window and completing a successful experiment campaign is markedly improved;

— the experimental system can, on a single flight, run the injection and sampling protocol multiple times;

— the controlled descent rate of the suspended payload ensures the isolation radical molecules in the inlet air stream from the walls of the ClO and BrO sensors;

— the system has greater latitude to select from a range of background meteorological conditions, adding a further degree of control to the experimental protocol; and

— the measurement of tracer species CO2, CO, N2O and CH4 ties all measurements to a widely used set of chemical coordinates, facilitating comparability with other stratospheric chemistry observations that include similar tracers, regardless of measurement platform (aircraft, balloon, satellite).

The development of stratospheric airships, SPBs and propulsion systems over more than three decades provides the engineering foundation for rapid, low-risk development of the SCoPEx platform. Our choice of a novel propelled balloon platform stems from the limited ability of existing stratospheric aircraft or balloons to meet the mission science requirements of low-velocity and long duration during periods of very light winds and low shear that occur on a seasonal basis in the lower stratosphere.

The scientific instruments build directly on a decades-long history of stratospheric composition measurements. These instruments provide high temporal resolution and high sensitivity to allow sampling of subtle chemical gradients that can be used to infer the time dependence of chemical reactions. These small-scale features cannot be measured by remote sensing methods that average over large spatial footprints, erasing essential information about chemical reactivity. The measurements made by SCoPEx provide context for measurements made on larger spatial scales and at longer time scales, bridging the gap between small-scale processes and prediction of the atmosphere’s response to large-scale forcing.

To be clear, while the small-scale nature of SCoPEx minimizes a number of risks, it also leaves a number of key uncertainties for other investigations. These include potential variations in aerosol microphysics arising from varying meteorological conditions, different aircraft wake characteristics and other particle generation techniques. There are also numerous uncertainties associated with geoengineering deployment—changes to large-scale atmospheric circulations and aerosol deposition at the surface, to name two—that are not addressed by SCoPEx.

External oversight and adherence to established safety practices are an essential part of the SCoPEx approach to risk management. The physical risks associated with scientific ballooning and custom instrumentation are managed using standard methods applied across all balloon missions. The size of the chemical perturbations in SCoPEx is tiny relative to chemical perturbations caused by a few minutes of flight of a commercial passenger aircraft.

In summary, we have presented a case for an outdoor experiment to test the risks and efficacy of SRM. The motivation for outdoor experimentation is grounded in a larger scientific context and in the need to reduce uncertainties inherent in representing the complex atmospheric system in the laboratory, by a natural analogue, or in a model. The scientific results are expected to inform theoretical predictions about stratospheric composition in a changing climate with high-resolution, high-accuracy data.