Climate change in the 20th century is largely driven by increasing levels of greenhouse gases generated by human activities, such as those from burning fossil fuels.
The challenge is to track, understand and predict changes in greenhouse gas levels, and in the natural stocks and flows of carbon.
This is important due to the uncertainty about the future capacity of forests, soils and oceans to store carbon – with recent research suggesting a weakening in the Southern Ocean’s capacity.
There is also uncertainty about how climate change might affect methane and nitrous oxide emissions from agricultural activities.
A greater focus is needed on how rising temperatures, changing moisture availability, and altered fire regimes, for example, will affect the capacity of vegetation and land to act as a carbon sink. Ocean and terrestrial carbon cycle research is critical to inform discussions and negotiations on national and global emissions reduction targets.
The ACCSP investigates a range of topics that provide information on changes to greenhouse gas concentrations and how these affect our environment.
Through the Global Carbon Project (GCP) changes in greenhouse gas levels, sources and sinks of carbon are tracked so that global targets to reduce emissions can be monitored. A global carbon and methane budget is produced each year.
The Australian continental carbon balance project assesses the impact of fires on greenhouse gas emissions, and the influence of floods and droughts on the Australian carbon budget. These studies help to understand how rising temperatures and changing moisture conditions will affect the ability of the land to take carbon from the atmosphere.
This information is vital for development of agricultural and land management practices.
Researchers examine past changes of greenhouse gases through ice cores, to provide information about release and uptake of greenhouse gases over periods spanning past millennia to recent decades.
These studies also reveal how greenhouse gases respond to natural variability and how they may respond to human-induced climate change.