THE HEALTH OF THE OZONE LAYER

If we were to assume the role of a physician in order to diagnose the health of the ozone layer, no doubt we would state that our patient is in very poor health, and that the patient's condition is getting worse.

• In 1995, 1996 and now in 97 we have experienced record ozone depletions over both the Southern and Northern hemispheres.
• The 1996 Antarctic ozone hole reached a record 10 million square miles - an area greater than the total surface area of North America, and twice the size of Europe.
• During November and December of 1996, ozone levels over Northern Europe and the north Atlantic were 20% lower than the average measurements between 1957 and 1970. More than 25% ozone depletion was measured over some populated areas.
• Following the trend, in March 1997, the ozone layer was 15 to 25 percent thinner over the Arctic than it was a year earlier, and Environment Canada reported a record of nearly 40% ozone depletion over the North West Territories.
• The European Commission's Environment and Climate Programme reported in May, 1997, that "For the third winter in succession, record low temperatures in the Arctic's lower stratosphere, coupled with the presence of man-made pollutants, have resulted in...up to 40% ozone depletion in the Northern Hemisphere...[with] total ozone as low as 270 Dobson Units near the pole during March this year."¹¹

Of further concern is the recurrence of extremely cold spring time temperatures over the Arctic, which is a precondition for increased ozone depletion. The European Commission noted that "Analyses of stratospheric temperature data shows that the stratosphere during March 1997 was by far the coldest on record. The average monthly mean over the Pole was some six degrees lower than the previous minimum average. These very low temperatures in the Arctic springtime for the third successive year give rise to the concern that they may be part of a longer-term trend. It is important to understand whether, for example, this represents part of changes induced by chemistry-climate feedback."¹²

Concurrently, scientists are reporting alarming data due to increases of UV-B radiation. For example, scientists have known for years that UV-B radiation reduces the reproduction of phytoplankton, the micro-organism at the bottom of the marine food chain which are vital to the survival of marine animals; but this past year they have also found species of fish with UV-B induced skin cancer and DNA damage. In other findings, the 1996 UNEP Scientific Assessment states that "recent studies suggest that potentially detrimental effects of UV-B radiation in evergreen woody plants may accumulate from year to year...and that there are accumulating and intensified adverse effects on plants from generation to generation." In other words, UV-B damage is cumulative and passed on from one generation to the next.

The environmental imperative has always been, and continues to be, to stop using all ozone depleting substances as quickly as possible, without resorting to the use of substances, such as HFCs, that significantly exacerbate the crises of global warming and the toxification of the environment.

The alarming state of the ozone layer dictates that it is essential, from both a short term and a long term perspective, that the Parties to the Protocol adopt policies that aim to eradicate the use of all ozone destroyers on an emergency time scale. Greenpeace calculations show that an emergency phase out of ozone depleting substances could accelerate recovery of the ozone layer by nearly fifteen years (to 2026) and this would reduce ozone depletion by nearly 40%.

The goal must be not only to minimize further ozone loss, but ultimately, to facilitate - as much as it is humanly possible - the earliest recovery of the ozone layer.

¹¹ Press Release, Brussels, May 5, 1997, European Commission's Environment and Climate Programme [return]

¹² Press Release, Brussels, May 5, 1997, European Commission's Environment and Climate Programme [return]