The ozone layer is
about 20 to 30 kilometers from the ground, which can absorb most of the sun's
harmful ultraviolet rays, offering an "umbrella" to the earth. The
Antarctic Ozone Layer is the depletion phenomenon of ozone in the Antarctic
ozone layer. Over the past 15 to 20 years, there has been a considerable loss
of Antarctic ozone in the spring. Figure 1 shows the change in the
concentration of ozone in Antarctica from 1996 to 2012.
Figure 1. The Antarctic Total Ozone
Columns1 (DU) 2 (Source: NASA).
It has been suggested that the ozone layer has been recovering since 2000:
the size of the ozone hole has decreased, the amount of ozone in the atmosphere
has increased, and ozone concentration has increased in the vertical direction.
Figure 2 shows the change in average total ozone columns measured at the
selected station from 1979 to 2013 (Kuttippruath, 2017). The
results show that the Montreal Protocol3 may help with the recovery of Antarctic ozone layer.
However, some views argue that ozone layer recovery may be delayed. There are some reasons：
Short - lived compounds could be a new threat to the ozone layer.
Ozone hole recovery may because of global warming.
The resilience of the Antarctic ozone remains unstable.
It will take a long time before the hole has completely recovered.
Volcanic eruptions can have a significant impact on the healing ofthe ozone hole, as seen with the Calbuco outbreak in October 2015.
So,here is the question -- Does the ozone hole matter or not? For answering this question, this blog will explore these issues:
The mechanism of the ozone hole.
The impacts of the ozone hole.
The recovery of the ozone hole.
The latest views towards the ozone hole.
The latest findings related to the ozone hole.
1 Total ozone columns: the total amount
of ozone in the vertical column of the atmosphere.
2 DU: Unit to
describe the density of ozone in the atmosphere.
3 Montreal Protocol: An global treaty to reduce emissions of
ozone-depleting substances.
4 The red line: All measurements of the selected Antarctic station.
5 The green line: Measurements within
the Antarctic vortex.
Ask any questions at will!
Informative!
ReplyDeleteI also learned a lot from the four articles discussing the delay of the ozone layer recovery, and the instability of the ozone layer resilience.
Two thoughts that came to mind:
1) Climate Change was noted to slow the recovery of the ozone later because the greenhouse gases are trapping heat lower in the atmosphere - cooling the stratosphere, making the stratosphere a better environment for ozone destroying compounds to react with ozone.... my thought is, based on the other articles indicating that storms can expedite the transport of short-lived ozone destroying compounds to the top of the troposphere, I would also be inclined to wonder if climate change will additionally slow ozone layer recovery with the resulting increase of severe weather and storms which will transport ozone harmful compounds quicker to the stratosphere (not allowing time to for these compounds to degrade in the troposphere first). Is there any research into this?
2) The weaknesses of the Montreal Protocol (that are coming to light 30 years after it's creation) are good learning lessons for us as potential policy informers or deciders... such as: the implication today of having anonymity for exempted polluters; that when measuring ozone harmful compounds in the atmosphere it cannot be determined by scientists if these are the levels expected (based on known emitters and quantities), or if there are illegal emitters... also: that, since there is further science and understanding today than there was 30 years ago, short-lived ozone destroyers are now known to be a concern, but were not included in the protocol at the time of it's creation...... these two points make me see that policy can only be as good as the science at the moment of it's creation; and therefore, to account for this, the planning for and execution of regular reviews and updates to policies are imperative.
Also: Shout out to UCL's David Rowley for being featured in 2 articles here!
Echo point 2), the policy decision makers should have the latest update, an early phase-out and reduction of these species of destroyers could have an early benefit to reduce the global warming.
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