State and trends of the Antarctic atmosphere

Component
Summary
Grade
Very poor Poor Good Very good
Confidence
In Grade In Trend
Comparability
To previous years

Long-term measurements exist only at a limited number of sites (primarily since 1957). Satellite remote-sensing measurements primarily began in the late 1970s

Annual average temperatures have generally increased throughout Antarctica since 1957, with the most marked warming occurring in the Antarctic Peninsula region and West Antarctica

Year(s): 
2016
2
Deteriorating
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Comparable

Long-term measurements exist only at a limited number of sites (primarily since 1957), and large-scale analyses have used satellite thermal infrared data.

 

The temperature increase in the West Antarctic Ice Sheet has been 0.1°C per decade

 

Year(s): 
2011
2
Deteriorating
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Not assessed

Satellite and radiosonde measurements are available; the most extensive and reliable data have been available since the late 1970s

A general warming trend, linked to human factors, is taking place in the lower troposphere; the trend decreases towards the tropopause

Year(s): 
2016
2
Deteriorating
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Comparable

Satellite and radiosonde measurements are available; most extensive and reliable data have been available since the late 1970s The general warming trend, linked to human factors, is taking place in the lower troposphere; the trend decreases towards the tropopause

Year(s): 
2011
2
Deteriorating
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Not assessed

Satellite and radiosonde measurements are available; the most extensive and reliable data have been available since the late 1970s

A general cooling trend is most significant across the Antarctic continent in spring and summer because of the annual formation of the ozone hole

Year(s): 
2016
2
Deteriorating
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Comparable

Satellite and radiosonde measurements are available; most extensive and reliable data have been available since the late 1970s. The general cooling trend is most significant over the Antarctic continent in spring and summer due to annual formation of the ozone hole

Year(s): 
2011
2
Deteriorating
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Not assessed

Limited satellite and ground-based remote-sensing data are available; however, there is some evidence of decreasing temperatures, but modes of variability make interpretation complex

Year(s): 
2016
2
Unclear
Confidence (in grade): 
Limited
Confidence (in trend): 
Limited
Comparability (to previous reports): 
Comparable

Limited satellite and ground-based remote sensing data are available; however, there is some evidence of decreasing temperatures, but modes of variability make the interpretation complex

Year(s): 
2011
2
Unclear
Confidence (in grade): 
Limited
Confidence (in trend): 
Limited
Comparability (to previous reports): 
Not assessed

Few tropospheric measurement sites exist in Antarctica and the subantarctic, but increases in carbon dioxide and methane linked to human factors are apparent

Year(s): 
2016
2
Deteriorating
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Comparable

There are few tropospheric measurement sites in Antarctica and the subantarctic, but increases in carbon dioxide and methane linked to human factors are apparent

Year(s): 
2011
2
Deteriorating
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Not assessed

There are possible signs of recovery (increased concentration of ozone) in spring and summer above Antarctica, but there is also significant interannual variability because of meteorological factors

Stronger signs of ozone recovery are expected during the next 1–2 decades

Year(s): 
2016
3
Improving
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Comparable

There are possible signs of recovery (increased concentration of ozone) in spring and summer over Antarctica, but there is also significant inter-annual variability due to meteorological factors. Stronger signs of ozone recovery are expected over the next decade or two

Year(s): 
2011
3
Stable
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Not assessed

Improvement (i.e. decrease) in ozone-depleting substances (ODSs) is expected in the troposphere

Estimates of effective equivalent stratospheric chlorine (EESC) in the stratosphere are based on the level of tropospheric ODSs, combined with transport modelling

Year(s): 
2016
3
Improving
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Comparable

Improvement (decrease) in ODSs is expected in the troposphere. Estimates of EESC in the stratosphere are based on the level of tropospheric ODSs combined with transport modelling; however, few measurements of EESC are available

Year(s): 
2011
3
Improving
Confidence (in grade): 
Adequate
Confidence (in trend): 
Adequate
Comparability (to previous reports): 
Not assessed

EESC = effective equivalent stratospheric chlorine; km = kilometre; ODS = ozone depleting substance

Klekociuk A, Wienecke B (2016). Antarctic environment: State and trends of the Antarctic atmosphere. In: Australia state of the environment 2016, Australian Government Department of the Environment and Energy, Canberra, https://soe.environment.gov.au/assessment-summary-71-state-and-trends-antarctic-atmosphere, DOI 10.4226/94/58b65b2b307c0