aerosols

British Balloon to spew sulfur, another wacky geoengineering scheme

In order to forestall dread global warming, many, usually wacky, schemes have been proposed. The latest is from a group of British academics who want to simulate the cooling emissions of volcanoes by tethering a balloon about 1 kilometer into the sky and pumping up and dispersing a chemical mixture of sulfates to reflect sunlight. Of course, the EPA has for years been trying to reduce sulfur emissions from coal plants and automobile exhausts.

Floating-wind-farm

The academics have garnered a £1.6m ($2.5 million) British government grant to build a scale model of their device.

“The whole weight of this thing is going to be a few hundred tonnes. That’s the weight of several double-decker buses. So imagine how big a helium balloon do you need to hold several double-decker buses – a big balloon. We’re looking at a balloon which is possibly 100-200m in diameter. It’s about the same size as Wembley stadium,” said the Oxford engineering lecturer Hugh Hunt in an interview earlier this year. This hose would be just like a garden hose, 20km long and we pump stuff up the pipe.”

Read the whole story from the British newspaper, the Guardian.

For more wacky geoengineering schemes, see my post:

Geoengineering Wacky Schemes to Control Climate

NASA says volcanoes, not coal burning is major source of sulfur dioxide in atmosphere

Sulfur dioxide (SO2) aerosols in the atmosphere are due mainly to increasing volcanic activity not from burning coal, according to NASA.  Sulfur dioxide aerosols have a cooling effect and have recently been blamed for “hiding global warming.”

Citation: Vernier, J.-P., et al. (2011), Major influence of tropical volcanic eruptions on the stratospheric aerosol layer during the last decade, Geophys. Res. Lett., 38, L12807, doi:10.1029/2011GL047563.

The abstract reads:

The variability of stratospheric aerosol loading between 1985 and 2010 is explored with measurements from SAGE II, CALIPSO, GOMOS/ENVISAT, and OSIRIS/Odin space-based instruments. We find that, following the 1991 eruption of Mount Pinatubo, stratospheric aerosol levels increased by as much as two orders of magnitude and only reached “background levels” between 1998 and 2002. From 2002 onwards, a systematic increase has been reported by a number of investigators. Recently, the trend, based on ground-based lidar measurements, has been tentatively attributed to an increase of SO2 entering the stratosphere associated with coal burning in Southeast Asia. However, we demonstrate with these satellite measurements that the observed trend is mainly driven by a series of moderate but increasingly intense volcanic eruptions primarily at tropical latitudes. These events injected sulfur directly to altitudes between 18 and 20 km. The resulting aerosol particles are slowly lofted into the middle stratosphere by the Brewer-Dobson circulation and are eventually transported to higher latitudes.

See also:

Volcanoes may have greater influence on climate than previously thought

So now burning coal causes cooling?

Volcanoes may have greater influence on climate than previously thought

A newly published French study of last year’s eruption of the Eyjafjallajökull Volcano in Iceland suggests that models have underestimated the aerosol formation and hence cooling effect of volcanic eruptions “by 7 to 8 orders of magnitude.”

The Abstract reads:

Volcanic eruptions caused major weather and climatic changes on timescales ranging from hours to centuries in the past. Volcanic particles are injected in the atmosphere both as primary particles rapidly deposited due to their large sizes on time scales of minutes to a few weeks in the troposphere, and secondary particles mainly derived from the oxidation of sulfur dioxide. These particles are responsible for the atmospheric cooling observed at both regional and global scales following large volcanic eruptions. However, large condensational sinks due to preexisting particles within the plume, and unknown nucleation mechanisms under these circumstances make the assumption of new secondary particle formation still uncertain because the phenomenon has never been observed in a volcanic plume. In this work, we report the first observation of nucleation and new secondary particle formation events in a volcanic plume. These measurements were performed at the puy de Dôme atmospheric research station in central France during the Eyjafjallajokull volcano eruption in Spring 2010. We show that the nucleation is indeed linked to exceptionally high concentrations of sulfuric acid and present an unusual high particle formation rate. In addition we demonstrate that the binary H2SO4 – H2O nucleation scheme, as it is usually considered in modeling studies, underestimates by 7 to 8 orders of magnitude the observed particle formation rate and, therefore, should not be applied in tropospheric conditions. These results may help to revisit all past simulations of the impact of volcanic eruptions on climate.

Besides primary ash, the researchers say that sulfur dioxide, which oxidizes to sulfuric acid, can act as cloud-forming nuclei that can change the precipitation over a region. The clouds would also partially reflect solar irradiance and therefore contribute to cooling.

UPDATE: New NASA paper says volcanoes primarily responsible for increased SO2:

Recently, the trend, based on ground-based lidar measurements, has been tentatively attributed to an increase of SO(2) entering the stratosphere associated with coal burning in Southeast Asia. However, we demonstrate with these satellite measurements that the observed trend is mainly driven by a series of moderate but increasingly intense volcanic eruptions primarily at tropical latitudes.

See also:

Iceland volcano and its effect on life Photos

Icelandic Volcanoes Geologic Setting

Katla volcano in Iceland may be priming to erupt

Yellowstone Super Volcano

Carbon Dioxide and the Greenhouse Effect