State where the ozone hole referred to in Figure 1 is located.
in the (lower) stratosphere / over the poles / above the Antarctic/Arctic / at higher latitudes / Australia/NZ
Describe the changes in mean ozone hole area between 1979 and 2016.
Award
- rapid increase during the 1980s/up to 1990s/ from 1979–87;
- reaches maximum in late 1990s; relative stable during late1990s;
- fluctuating from 2000 onwards;
- possibly declining in late 2000s/from 2014;
Be prepared to give a little leeway in precise years for changes in trends, but some reference to their timing is required.
Identify one possible reason for the changes shown during the 1980s.
Award
increasing use of/disposal of refrigerants containing CFCs;
increasing use of CFCs in aerosols;
increasing release of NO_x_ from fossil fuel combustion; increasing use of methyl bromides as pesticides;
Responses should identify the ODS and its use for full credit.
Explain how the data in Figure 1 can be used in judging the success of the Montreal Protocol in addressing ozone depletion.
Award
- Montreal Protocol was introduced in 1987/graph covers period before and after introduction of Montreal Protocol;
- it introduced a ban on the use of CFCs / led to use of alternative HCFs/HFs;
- rate of ozone destruction/growth of the ozone hole slows down/stops soon after this date;
- suggesting it had some success/favourable impact on ozone depletion;
- however, there is little evidence of ozone levels being restored to earlier levels / hole disappearing;
- possibly some evidence in last few years/2014–2016 on graph of ozone hole reducing/ozone being restored;
- the stabilisation/limited decline in ozone hole may suggest black market sale of ODSs (limited success);
- continued impact of long-lasting ODSs (CFCs/HCFs) delay final judgement;
