The ozone hole over Antarctica was the largest recorded following the Mt. Pinatubo eruption on June 12, 1991.
Climate engineers excited by the global temperature drop following the Pinatubo eruption seem to ignore that the cooling accompanied the largest ozone hole measured. Regardless, this volcanic eruption marks the genesis of all current solar geoengineering modelling and experiments.
Sub-Microscopic Oxide Particulates. During the present decade, the eruption of Mt. Pinatubo in the Philippines induced a transient drop in the global mean temperature of ~0.5˚ K, apparently due to insolation modulation by volcanic particulates.26 It is believed that this cooling was induced predominantly by scattering of sunlight by SO2-based particulates of sub-micron scale, ones which may have grown into more effective scatterers by scavenging residual stratospheric water and cations, resulting in myriad still-sub-micron droplets of high-concentration sulfur acids and salts. Indeed, it has been suggested that the advent of marked greenhouse effects due to CO2 emissions has been delayed through the present time by the simultaneous emission of large quantities of sulfate particulates (primarily arising from the ~2±1% sulfur content by weight of typical fuel-grade coal), resulting in significant tropospheric scattering of sunlight.27 To these extents, the case of dielectric scattering-based insolation modulation already has some empirical basis. 
The National Aeronautics and Space Administration reported yesterday that a satellite passing over Antarctica had measured the lowest stratospheric ozone level on record, an ominous indication of potential global health risks.
Dolores Beasley, a spokeswoman for the agency's Goddard Space Flight Center at Greenbelt, Md., said the measurement was made Sunday by the total ozone mapping spectrometer, or TOMS, an instrument aboard the Nimbus-7 satellite.
Dr. Arlin Krueger, a Goddard scientist, said the ozone level in the Antarctic stratosphere was measured that day as 110 Dobson units. Dobson units measure the atmosphere's ability to absorb and block certain wavelengths of light coming from the Sun, notably ultraviolet radiation. In normal times, the atmosphere above Antarctica measures about 500 Dobson units, but values far below this have been recorded in recent years when seasonal "ozone holes" have developed over the southern continent.
The Antarctic ozone hole that has just appeared is the fourth severe one to develop since 1986, the year that significant ozone depletion of the stratosphere was first observed. Atmospheric scientists regard seasonal ozone holes as part of a much larger potential problem: a worldwide depletion of stratospheric ozone.
Possible Health Problems
Public-health experts fear that the increasing intensity of ultraviolet radiation that now penetrates the atmosphere may greatly increase the incidence of skin cancer and cataracts, and could significantly diminish global crops and the marine food chain.
"The minimum ozone on Oct. 6, 1991, is the lowest we have ever seen with the TOMS instrument in its 13-year record of data," Dr. Krueger said. "Although the data are preliminary, we expect that the final results will confirm this conclusion." 
Related Timeline Entries
If any of the links above do not work, copy the URL and paste it into the form below to check the Wayback Machine for an archived version of that webpage.