The monitoring station located remotely in northwest Tasmania has been monitoring what could be referred to as some of the purest air in the world for half a century now, providing unique insights into the influence of human activity on atmospheric composition.

Kennaook / Cape Grim Baseline Air Pollution Station was established in April 1976 and positioned in a way to monitor the winds blowing the air that had not come into contact with land or pollution for hundreds of kilometers before reaching the station. Thus, the air monitored here can be used for research of "baseline air" – air that is not affected by recent human emissions.

Why is this station important?

Unlike monitoring stations located in cities, the Cape Grim monitoring station serves as a global baseline for studying the atmosphere. The measurements taken here allow scientists to separate the natural atmosphere from any changes made to it by humans.

The monitoring station measures greenhouse gases like carbon dioxide and methane, aerosols, and over 80 other types of air pollutants, among which are ozone-depleting substances.

What have scientists discovered?

Data gathered over 50 years indicate a definite increase in the concentration of carbon dioxide, which is connected with human actions, such as the burning of fossil fuels. On the other hand, there has been a reduction in the quantity of other substances, like black carbon and chlorofluorocarbons (CFCs).

Scientists believe that the decrease in pollutants is due to global treaties, such as the Montreal Protocol, that aimed to eliminate ozone-depleting gases.

These findings reveal two significant aspects of environmental protection: emissions can continue rising without action, while global cooperation can help in reducing specific chemicals.

How is the monitoring process carried out?

Air is consistently extracted from intake stations, such as one installed at 80 meters high from the surface, and measured instantaneously. Additionally, seasonal samples of air are retained in tanks for further analysis.

The laboratory is operational at all times, contributing to the World Meteorological Organization’s Global Atmospheric Watch project.

What's the global significance?

Observations at Cape Grim play a role in determining whether emissions reduction policies are effective, since they are used for assessing climate and reaching global warming agreements.

This shows that despite the increase in greenhouse gases, there are global actions that can be taken to decrease specific pollutants.

The big picture

Air pollution is one of the most significant problems in the world today, but it's difficult to determine its extent without data. This makes data collection extremely important for understanding how to address this issue.