What is the biggest contributor to climate change in Tasmania compared to other places in the world?

In most places, energy generation, using fossil fuels, is the largest contributor to climate change. In contrast, Tasmania is lucky to have a low-emissions energy generation – much of our energy is produced by hydroelectricity. The single biggest emitter of greenhouse gases in Tasmania is the agriculture sector – which contributes 34% of our overall greenhouse gas emissions. However, carbon accounting (the process of calculating overall emissions and offsets) is quite complex in Tasmania. Let’s take a look…

In fact, Tasmania is one of the few places in the world to have already achieved “net-zero” status. That means, Tasmania currently takes more carbon from the atmosphere than it emits - absorbing and storing carbon in our forests and our soils. Tasmania’s greenhouse gas emissions in 2020 were -3733 kilotonnes CO₂ – e:  “CO₂ – e” means “carbon dioxide equivalent”. This is a measure used to compare the emissions from various greenhouse gases based on their global warming potential.

Tasmania’s negative emissions profile is a nationally and internationally significant achievement, but there is more to the story. If we want to keep this status, we can’t be complacent. Currently, Tasmania’s main emissions come from agriculture (34%), industrial processes (19%), transport (21%), non-hydro energy generation (21%) and waste (5%). Tasmania’s main “offsets” – or sources of carbon absorption – are forests and soils: a sector known in carbon accounting as “land use, land use change and forestry” or “LULUCF”. So Tasmania’s emissions profile looks like this:

Keeping our emissions profile low over the longer term will mean we need to do better at cutting our overall (or “gross”) emissions – on the left, above. In fact, we haven’t reduced these emissions much for 30 years, and emissions from agriculture have increased the most over the last decade. Importantly, research shows us that the effects of climate change – like rising temperatures, bushfires, and changing rainfall patterns – will decrease Tasmanian forests’ capacity to absorb carbon. Also, continued old-growth forest clearing and the maturing of managed forests means that over time, our forests be less of a carbon sink. If Tasmania keeps a business-as-usual approach, emissions will remain below net-zero until about 2025, but, from 2030 onwards particularly in years with major bushfires, Tasmania will likely become an emitter of carbon once again.

We therefore need to work to reduce gross emissions, and better protect our original forests to keep our net-zero status long term.