PowerPoint Presentation

Antarctic Ozone Hole Review2012Craig S. Long1Larry Flynn2, Bryan Johnson3

NOAA1-NWS/NCEP/Climate Prediction Center2-NESDIS/STAR/Satellite Meteorology & Climatology Division3-OAR/ESRL/Global Monitoring DivisionQuick ozone reviewOzone generation cycleOzone depletion cyclesOzone recovery expectationsNOAA-centric perspective2012 ozone hole in context of 32 previous yearsVarious ways to monitor and measure ozone holeMeteorological conditions accountable for 2012 ozone size and longevityOutlineOzone Life Cycle

Ozone Destruction CycleFrom 2010 Ozone Assessment

Reservoir moleculesDeNitrificationActivationWhy Ozone Holes form over Antarctica and Not the Arctic

From 2010 Ozone AssessmentOzone Recovery Protocols

From 2010 Ozone Assessment

Ozone Recovery ExpectationsFrom 2010 Ozone Assessment

From 2010 Ozone AssessmentOzone Recovery Expectations2012 Antarctic Ozone HoleOzone Hole definition:Area in which total column ozone is less than 220 DU

Satellite PerspectiveSouth Pole Perspective

Suomi-NPP OMPS Total Ozone

Ozone Hole Time Series

Ozone Hole Annual Maximum SizeUsing SBUV/2 v8 analyses

Ozone Hole Annual Mean Size Late Sept

Ozone Hole Monthly Mean

Monthly Mean Ozone Analysis

South Pole Ozonesonde Measurements

Comparison of 2012 with 2006 which had near complete ozone depletion

South Pole Ozonesonde Measurements

South Pole Ozonesonde Measurements

South Pole Ozonesonde Measurements

South Pole Spectrophotometer MeasurementsLate OctoberBy late October the break down of the polar vortex lead to the early end of the 2012 ozone hole resulting in anomalously high total ozone values.Meteorological ConditionsPSC AreaDefines the potential size of ozone depleted airVortex AreaSeparates cold/ozone depleted polar air from ozone rich warmer mid-latitude airDefines longevity of ozone holeWhat modulates these:Wave activity and heat flux from mid-latitudes

Area of PSC Temps and Polar Vortex

Vortex, Temperature, Ozone Relationship

Note how the high ozone values coincide with the warm temperatures surrounding the polar vortex.Note how the polar vortex separates the ozone rich middle latitudes from the depleted ozone values inside.SH Polar Temperatues

50hPa SH high latitude temperatures were warm than last year and near the long term average during the SH winter/spring months. The temps raise rapidly in October due to the early vortex breakdown.

2hPa SH high latitude temperatures were consistently warm during the SH winter/spring months.

20062012Volume of Cold Air

Compared to a year (2006) with a large ozone hole, the PSC area at various levels in 2012 were much smaller.

Comparison of 2012 PSC Area with Previous Years

Zonal Mean Temperature AnomalyComputing the mean 100-30 hPa PSC area from mid August through mid-September shows a smaller value than seen in the 200s. But not different from other years. The lower plot shows a strong anti-correlation of the 65-90S 50 hPa mean temperatures with the PSC area.

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SH Poleward Heat FluxHeat flux activity showed several pulses in 2012 which raised temperatures and decreased the size of the PSC area/volume. The strong pulse in mid October lead to the vortex break-down and filling in of the ozone hole.

Heat Flux [vT] (deg m sec-1)50 hPa TemperatureJul/Aug 100mb Heat Flux vs Aug/Sep 50mb Temps2012

Heat Flux [vT] (deg m sec-1)50 hPa TemperatureComparison of Heat Flux/Temp Relationship between MERRA and CFSR

Wave 1 and 2 activity transports heat towards polar region.

Increases the temperature in the polar vortex. Shrinks the area of PSCs.Heat Flux Impacts on Polar Temperatures

Descending easterliesRole of QBO

Low Tropical OzoneHigh Polar OzoneBD Circulation Speeds UpHigh Polar OzoneDescending Easterlies

Descending cold anom

Low Ozone in Tropics, High in Extra-tropics and South Polar Region

SP August Ozone Levels are well above meanSummarySH Polar temperatures were warmHeat Flux activity was greatPSC area was smallOzone Hole size is extremely smallWave activity and temperatures dont necessarily explain why the ozone hole size was so small.South Pole ozonesondes imply ozone levels were well above normal.Perhaps ozone depletion was equivalent to other years yet due to higher starting point the area below 240 DU threshold was smaller than those same years.Strong wave activity in Oct resulted in early end of ozone hole