Tasmanian Greenhouse Gas Emissions Report 2024

I am pleased to report that Tasmania has again achieved net negative greenhouse gas emissions. In the latest greenhouse gas inventory for Tasmania, our net greenhouse gas emissions for 2022 were minus 4.34 megatonnes (Mt) of carbon dioxide equivalent (CO₂‑e), which is a decrease of 122.2 per cent from the baseline year of 1990.

We were the first Australian jurisdiction to achieve net zero emissions, which we reached in 2014. We have maintained this status for the last nine reported years. This accomplishment reflects our longstanding investment in renewable energy generation, and the sequestration capacity of our forests. Our economy and population have also grown significantly since the baseline year, demonstrating that a low emissions transition is achievable.

Tasmania’s climate change legislation sets a target of net zero emissions, or lower, by 2030. The target complements our commitment to increasing Tasmania’s renewable energy output by 200 per cent of our 2020 demand by 2040, recognising that clean energy is at the core of our decarbonisation agenda.

In addition to the target, the legislation also requires the government to prepare a climate change action plan, climate change risk assessment, and emissions reduction and resilience plans for key sectors, and update them every five years.

Other initiatives underway include a large-scale trial of Asparagopsis seaweed feed supplements to help farmers to reduce livestock methane emissions, and assisting landowners to plant trees on their land through the Stems for CO2 program, in partnership with Private Forests Tasmania. In the transport sector, our e-transport support package provided rebates for electric vehicles, e-mobility devices like e-bikes, and interest-free loans for charging infrastructure.

We are committed to an integrated, whole-of-government approach to climate change action and supporting the Tasmanian economy in a successful low emissions transition.

The Honourable Nick Duigan MLC

Minister for Energy and Renewables

This report presents an overview of Tasmania’s greenhouse gas emissions (called ‘emissions’ in this report) sources and sinks from 1990 to 2022. The report details emissions from goods and services produced in, and exported from, Tasmania.

Emissions are reported in financial years to 30 June, so the year 2022 refers to the financial year 1 July 2021 to 30 June 2022. This report uses the most recent official data in Australia on annual emissions. The data are prepared and released by the Australian Government, in accordance with agreed international reporting frameworks and guidelines.

Under Tasmania’s climate change legislation, the Climate Change (State Action) Act 2008, Tasmania has an emissions reduction target of net zero emissions, or lower, from 2030. The legislation requires the government to prepare a report about Tasmania’s greenhouse gas emissions and our progress towards achieving our emissions reduction target.

The Climate Change (Greenhouse Gas Emissions) Regulations 2022 require the responsible Minister to publish Tasmania’s greenhouse gas emissions for the calendar year to which the Australian Government’s Greenhouse Gas Inventory relates.

What are greenhouse gases?

Greenhouse gases trap heat in the atmosphere and make the earth warmer. These gases occur naturally but are also produced by human activities.

Gases with the most significant impact on global warming are water vapour, carbon dioxide (CO₂), methane, and nitrous oxide. Other common greenhouse gases include hydrofluorocarbons, perfluorocarbons, and sulphur hexafluoride.

How are emissions measured?

Each greenhouse gas varies in terms of its contribution to climate change. Global warming potentials (GWPs) are values that allow direct comparison of the impact of the different greenhouse gases in the atmosphere by comparing how much energy one tonne (t) of a gas will absorb compared to one tonne of carbon dioxide. The consistent value of carbon dioxide equivalent (CO₂-e) has the lowest GWP factor of one. All other greenhouse gases have a GWP which is a certain number of times greater than carbon dioxide, as shown in the table below.

Table 1: Global Warming Potential of greenhouse gases

For example, 1 tonne of methane results in the equivalent global warming of 28 tonnes of carbon dioxide, and is therefore measured as 28 t CO₂-e.

What are carbon sinks?

Plants, soils, and oceans can remove more carbon dioxide from the atmosphere than they emit. The removed carbon is stored, often in the form of growing vegetation. This process is known as sequestration. An area that stores a lot of carbon, like a forest, is called a ‘carbon sink’.

How are emissions reported?

Reporting framework

Tasmania’s emissions are reported in accordance with the Intergovernmental Panel on Climate Change (IPCC) reporting framework for national greenhouse gas inventories. This framework is used by the 199 members who are signed up to the international United Nations Framework Convention on Climate Change (UNFCCC) to report their greenhouse gas inventories.

Data source – Australia’s National Greenhouse Gas Accounts

The main source of data on Tasmania’s emissions is the Australian Government’s State and Territory Greenhouse Gas Inventories (STGGI). The STGGI is a disaggregation of the data contained in Australia’s National Greenhouse Gas Accounts and the National Inventory Report (NIR).

To meet our international greenhouse gas inventory reporting commitments, including compliance with the Paris Agreement, the Australian Government submits the NIR to the UNFCCC every year.

For the first year of the Paris Agreement reporting period, which is the financial year 2020-21, and onwards, estimates of Australia’s emissions are compiled consistent with:

• procedures and guidelines in the Paris Agreement, particularly Article 13
• the Intergovernmental Panel on Climate Change (IPCC) 2006 Guidelines for National Greenhouse Gas Inventories (the Guidelines)
• the IPCC 2019 Refinement of the 2006 IPCC Guidelines
• the IPCC 2013 Wetlands Supplement
• country-specific methodologies consistent with the Guidelines and intended to improve emissions accuracy.

Australia mostly uses country-specific methodologies and emission factors to compile NIRs. The methodologies used to estimate Australia’s inventory have been improved over time and will continue to be refined as new information emerges, and as international best practice evolves.

The Department of Climate Change, Energy, the Environment and Water (DCCEEW) is responsible for Australia’s greenhouse gas emissions reporting. DCCEEW is responsible for all aspects of the national inventory systems, including activity data coordination, emissions estimation, quality control, and preparation of reports. DCCEEW submits the reports to the UNFCCC on behalf of the Australian Government.

The NIR runs two years behind the current date and represents the most recent official data in Australia on annual emissions. The current NIR shows estimates of Australia’s emissions for the period 1990 to 2022. As historical figures are revised each year, to account for recalculations and methodology changes, the latest NIR data cannot be compared with reports from previous years.

Under the UNFCCC, the NIR must report net emissions from the following sectors:

• energy
• industrial processes and product use (IPPU)
• agriculture
• land use, land use change and forestry (LULUCF)
• waste.

For the purposes of this report, the energy sector is broken down into three sub-sectors:

• electricity generation
• the direct combustion of fuels from all other forms of stationary energy, excluding electricity generation (direct combustion)
• transport.

Within the STGGI, electricity generation is reported under the energy sub-sector ‘energy industries’. In this report ‘direct combustion’, for Tasmanian emissions, has been aggregated to include the STGGI energy sub-sectors of ‘fugitive emissions’, ‘manufacturing industries and construction’ and ‘other sectors’.

The STGGI data relates to production-based, rather than consumption-based emissions in Tasmania, which are called scope 1 emissions. This means that the data account for emissions from goods and services produced in Tasmania, rather than from goods and services that are imported and consumed.

Confidential information

As part of the National Energy and Greenhouse Reporting Scheme, the Australian Government treats some data as confidential. These data are aggregated with other sectors before publication. This happens when reporting at a sub-sector level could lead to the disclosure of commercially-sensitive emissions data reported by an organisation.

For example, there are very few industrial sites that produce fugitive emissions in Tasmania, so the Australian Government treats Tasmania’s fugitive emissions as confidential to avoid identification of individual businesses.

This rule also applies to emissions from the ‘metal industry’, and ‘other’ sub-sectors, including ‘pulp and paper’ and ‘food and beverage industry’, which are reported as combined emissions in the IPPU sector.

Data source – Australian Bureau of Statistics (ABS)

This report also compares the time series of Tasmania’s emissions to the state’s Gross State Product (GSP) and population from 1990 to June 2022. GSP data were sourced from the ABS Australian National Accounts: State Accounts, 2022-23 (Cat No 5220.0).

Tasmania’s population data are sourced from ABS National, State and Territory Population, September 2022 (Cat No 3101.0).

Units of measure

Greenhouse gases are often reported in megatonnes (Mt) CO₂-e, where 1 Mt of CO₂-e is equal to 1,000 kilotonnes (kt) CO₂-e and 1 kt of CO₂-e is equal to 1,000 t.

Discrepancies in table totals

Data in the tables of this report are sourced directly from the STGGI. Any discrepancy between table totals and the sum of sectors and sub-sectors reflects rounding anomalies and/or the inclusion of confidential emissions data.

Variations in chart scaling

The sector-specific charts in this report are plotted on different scales to make them easier to read and may not be directly comparable with each other.

Tasmania’s emissions – 1990 to 2022

In 2022, Tasmania’s emissions were minus 4.34 Mt CO₂-e. Tasmania’s emissions decreased by 23.88 Mt CO₂-e between 1990 and 2022, which is a reduction of 122.2 per cent.

There is a clear downward trend in Tasmania’s net annual emissions from 1990 to 2022 (Figure 1). Tasmania first achieved net negative emissions in 2014 and has maintained this level each year to 2022.

Figure 1: Tasmania's emissions by sector and energy sub-sector - 1990 to 2022

Changes in the Land Use, Land Use Change and Forestry (LULUCF) sector have resulted in increased carbon sequestration, which has had a major influence on reducing Tasmania’s greenhouse gas emissions. LULUCF emissions were 23.78 Mt CO₂-e (Table 2), or 211.1 per cent, lower than 1990 levels.

Figure 2: Tasmania's emissions by sector and energy sub-sector, excluding LULUCF - 1990 to 2022

Excluding LULUCF, Tasmania’s emissions in 2022 were 8.17 Mt CO₂-e. This is a decrease of 0.11 Mt CO₂-e between 1990 and 2022.

Tasmania’s emissions, excluding LULUCF, were lowest in 2000 (7.35 Mt CO₂-e), highest in 2013 (8.64 Mt CO₂-e), and averaged 7.97 Mt CO₂-e between 1990 and 2022.

Emissions reductions

Reductions in emissions from 1990 to 2022:

• waste sector (down 0.17 Mt CO₂-e)
• energy sector (down 0.18 Mt CO₂-e)
• electricity generation sub‑sector (down 0.45 Mt CO₂-e).

Emissions increases

Increases in emissions over the period 1990 to 2022:

• IPPU sector (up 0.17 Mt CO₂-e)
• agriculture sector (up 0.08 Mt CO₂-e)
• transport sub-sector (up 0.19 Mt CO₂-e)
• direct combustion sub-sector (up 0.09 Mt CO₂-e).

Table 2: Tasmania's emissions by sector and energy sub-sector - 1990 to 2022

Tasmania’s emissions per person

In 2022, Tasmania had the lowest emissions per person of any Australian jurisdiction, at minus 7.6 t CO₂‑e per person (Figure 3). This is the only negative emissions figure per person of any Australian jurisdiction. The national average is 16.6 t CO₂-e per person.

Figure 3: Tasmania's emissions per person relative to Australia and other states and territories - 2022

Tasmania’s emissions per person have decreased from 42.3 t CO₂-e in 1990 to minus 7.6 t CO₂-e in 2022, a reduction of 118.0 per cent (-49.9 t CO₂-e) over 32 years (Figure 4).

Figure 4: Change in Tasmania's emissions per person - 1990 to 2022

When emissions from the LULUCF sector are excluded, the percentage change in Tasmania’s emissions per person relative to the baseline year of 1990 also declines, while Tasmania’s population has steadily grown (Figure 5).

Figure 5: Percentage change in Tasmania's population and emissions per person against 1990 baseline - 1990 to 2022

Tasmania’s emissions and Gross State Product

From 1990 to 2022, Tasmania’s real Gross State Product (GSP) increased by 115.4 per cent (to over $38 billion) while Tasmania’s emissions decreased by 122.2 per cent (Figure 6).

Figure 6: Change in Tasmanian emissions and real Gross State Product - 1990 to 2022

The increase in Tasmania’s GSP, coupled with the decrease in Tasmania’s emissions, has resulted in a reduction in the emissions intensity of the Tasmanian economy, from 1,102.8 to minus 113.6 t CO₂-e per million dollars of GSP (a reduction of 110.3 per cent) (Figure 7).

When the emissions from the LULUCF sector are excluded, the emissions intensity of Tasmania’s economy demonstrates a downward trend, declining from 467.3 t CO_2‑e to 214.2 t CO₂-e per million dollars of GSP between 1990 and 2022, which is a reduction of 54.2 per cent over this period.

Figure 7: Percentage change in Tasmania's real GSP and emissions intensity against 1990 baseline - 1990 to 2022

Tasmania’s contribution to national emissions

In 2022, Tasmania helped reduce Australia’s total emissions (432.62 Mt CO₂-e) by 1.0 per cent (Figure 8).

Figure 8: Tasmania's contribution to national emissions - 2022

This chapter details Tasmania’s emissions by the IPCC sectors of energy, agriculture, industrial processes and product use (IPPU), waste, and land use, land use change and forestry (LULUCF).

The energy sector is disaggregated into three sub-sectors: electricity generation, direct combustion (of fuels for stationary energy uses), and transport.

Tasmania’s emissions in 2022

Tasmania’s emissions in 2022 were minus 4.34 Mt CO₂-e. Emissions by sector and energy sub‑sector are shown in Figure 9.

• The LULUCF sector provided net sequestration of emissions (a carbon sink) of minus 12.51 Mt CO₂‑e, offsetting emissions from all other sectors.
• Excluding LULUCF, other sectors contributed 8.17 Mt CO₂-e to Tasmania’s emissions, as follows: energy (43.0 per cent), agriculture (32.7 per cent), IPPU (19.4 per cent), and waste (4.8 per cent).
• Excluding LULUCF, the energy sub-sectors accounted for the following share of total emissions: transport (21.1 per cent of emissions), direct combustion (20.6 per cent) and electricity generation (1.4 per cent).

Figure 9: Tasmanian emissions by sector and energy sub-sectors - 2022

Figure 10 highlights the differences in the relative contribution of each sector and energy sub‑sector for each Australian jurisdiction’s emissions. The LULUCF sector has been excluded from this analysis. The Australian Capital Territory has a unique emissions profile, as most of its electricity is supplied from renewable sources in New South Wales.

Tasmania’s emissions profile differs from other Australian states and territories, due to much lower contributions from the electricity generation sub-sector. Emissions from Tasmania’s transport, direct combustion, IPPU and agriculture sectors make a larger relative contribution to the state’s total emissions than in most other jurisdictions.

Figure 10: Relative contribution of each sector and energy sub-sector to an Australian state or territory's emissions, excluding LULUCF - 2022

Energy

Tasmania’s energy sector comprises electricity generation, direct combustion, transport, and fugitive emissions. There are very few sites that produce fugitive emissions in Tasmania, so the Australian Government treats Tasmania’s fugitive emissions as confidential to avoid identification of individual organisations.

For this report, ‘fugitive emissions’, ‘manufacturing industries and construction’ and ‘other’ sub-sectors are included in direct combustion. Tasmania’s energy sector contributed 3.52 Mt CO₂-e in 2022, accounting for 43.0 per cent of Tasmania’s emissions when LULUCF is excluded.

Compared to other states and territories (Figure 10), Tasmania has high levels of renewable electricity generation. This means most of Tasmania’s energy emissions are attributed to direct combustion and transport (Figure 11).

Figure 11: Breakdown of Tasmanian emissions by energy sub-sector (ex LULUCF) 2022

Transport

Emissions from the transport sub-sector are produced by the combustion of fuels such as petrol, diesel, and liquefied petroleum gas (LPG), in passenger, light commercial and heavy freight vehicles, railways, recreational boating and marine navigation, and aviation fuel for domestic airlines.

Emissions from electricity used to power electric vehicles, and from liquid fuels used to run logging and farming machinery such as log skidders and tractors, are accounted for in the electricity generation and direct combustion sub-sectors respectively.

Transport accounted for 1.72 Mt CO₂-e, which was 21.1 per cent of Tasmania’s emissions in 2022, excluding LULUCF (Figure 13). The emissions from transport increased by 0.19 Mt CO₂-e (12.4 per cent) between 1990 and 2022.

Figure 12: Tasmanian emissions from transport - 1990 to 2022

Direct Combustion

The direct combustion sub-sector is made up of emissions from the combustion of fossil fuels, for stationary energy purposes used directly on site, and fugitive emissions. Direct combustion includes burning coal, gas, agricultural waste, or forestry residue to generate heat, steam, or pressure for commercial and major industrial operations, and burning wood or gas for household heating and cooking. The activities and industries that cause these emissions include manufacturing, construction, agriculture, fisheries, residential uses, and commercial operations. There is no double counting of emissions from biomass consumption, including fuelwood, between the LULUCF and energy sectors.

Direct combustion accounted for 1.68 Mt CO₂-e, which was 20.6 per cent of Tasmania’s emissions in 2022, excluding the emissions from LULUCF (Figure 13). The emissions from direct combustion increased by 0.09 Mt CO₂-e (5.3 per cent) between 1990 and 2022.

Emissions from the combustion of fossil fuels such as natural gas at the Tamar Valley Power Station, and petrol and diesel used in passenger and heavy vehicles, are accounted for in the electricity generation and transport sub-sectors respectively.

Figure 13: Tasmanian emissions from direct combustion - 1990 to 2022

Electricity generation

Emissions from electricity generation are produced by the combustion of fossil fuels to generate electricity that is supplied to the electricity grid for domestic and commercial use.

This sub-sector covers emissions from electricity that is generated in Tasmania, some of which is exported to the National Electricity Market via Basslink.

In 2022, emissions from electricity generation accounted for 0.12 Mt CO₂-e, which was 1.4 per cent of Tasmania’s emissions, excluding LULUCF (Figure 14). The emissions from electricity generation decreased by 0.45 Mt CO₂-e (79.6 per cent) between 1990 and 2022.

Emissions from electricity imported into Tasmania via Basslink are accounted for in the greenhouse gas inventory of the state that generates the electricity.

Figure 14: Tasmanian emissions from electricity generation - 1990 to 2022

Agriculture

Sources of emissions from the agriculture sector include livestock digestive systems (enteric fermentation), the release of nitrous oxide from cropping and pastureland, and manure management. Agricultural emissions comprise:

• enteric fermentation of plant material that is digested by livestock (for example, cattle, sheep, and pigs) that results in methane emissions
• urine and dung deposited by grazing animals, and nitrogen leaching and run-off, resulting in emissions from microbial and chemical transformations that produce and consume nitrous oxide in the soil
• manure management practices that produce emissions through the anaerobic (without oxygen) decomposition of the organic matter contained in manure
• land management practices such as lime, fertiliser and urea applications, that produce nitrous oxide emissions.

Tasmania’s agriculture sector accounted for 2.68 Mt CO₂-e, which was 32.7 per cent of Tasmania’s emissions, excluding LULUCF (Figure 15). The emissions from agriculture increased by 0.08 Mt CO₂-e (3.0 per cent) between 1990 and 2022.

Emissions associated with the use of electricity and fuel consumption from operating agricultural equipment, and the fuel consumption used to transport farm products, are accounted for in the energy sector. Emissions associated with land use change, including the clearing and re-clearing of vegetation, are accounted for in the LULUCF sector.

Figure 15: Tasmanian emissions from agriculture - 1990 to 2022

Industrial processes and product use (IPPU)

Emissions from the IPPU sector are generated from a range of production processes that include the calcination of carbonate compounds (for example, cement, lime or glass production), carbon when used as a chemical reductant (for example, iron, steel or aluminium production), and the production and use of synthetic gases such as hydrofluorocarbons (used in refrigeration and air conditioning equipment and as solvents) and sulphur hexafluoride (used in electrical equipment).

In 2022, Tasmania’s IPPU sector accounted for 1.59 Mt CO₂-e, which was 19.4 per cent of the state’s emissions, excluding LULUCF (Figure 16). The emissions from IPPU increased by 0.17 Mt CO₂-e (11.9 per cent) between 1990 and 2022.

Emissions associated with the energy used in industrial production processes are accounted for in the electricity generation and direct combustion sub-sectors. For example, the emissions from cement manufacture may include combustion of fuels (coal or natural gas) used to heat kilns in the manufacturing process. However, these combustion-related emissions are reported in the energy sector (as direct combustion) and not with IPPU, which only includes the emissions from calcination.

Figure 16: Tasmanian emissions from IPPU - 1990 to 2022

Waste

Emissions from the waste sector are produced by the anaerobic decomposition of organic matter from solid waste in landfills and during the treatment of wastewater. Methane is produced by anaerobic digestion processes in wastewater treatment plants, and the nitrification and denitrification of urea and ammonia produces nitrous oxide emissions.

Emissions associated with the energy used in the management and transportation of waste are reported in the electricity generation, direct combustion, and transport sub-sectors.

In 2022, Tasmania’s waste sector accounted for 0.39 Mt CO₂-e, which was 4.8 per cent of Tasmania’s emissions, excluding LULUCF (Figure 17). The emissions from waste decreased by 0.17 Mt CO₂-e (30.6 per cent) between 1990 and 2022.

Figure 17: Tasmanian emissions from the waste sector - 1990 to 2022

Land use, land use change and forestry (LULUCF)

The LULUCF sector includes emissions and sequestration (removals or carbon sinks) of greenhouse gases from direct human-induced land uses, land use changes and forestry activities. These activities include emissions and sequestration associated with:

• the clearance of forested land and plantations, and the conversion to other land uses (for example cropland, grassland, wetlands and settlements)
• the establishment of new forests and plantations planted on previously unforested land
• other practices that change emissions and sequestration, such as forest management, cropland management and grazing land management.

Emissions from fuelwood consumption, controlled burning, and wildfires on forest land, are also included in the LULUCF sector, as are removals associated with post-fire recovery. Carbon that is stored in harvested wood products is included as a carbon sink.

The combustion of fossil fuels associated with forestry activity and land management (for example diesel to run logging machinery and farming equipment) is accounted for in the direct combustion sub-sector of the energy sector. Non-CO₂-e emissions associated with livestock (such as methane from enteric fermentation) and cropping (such as release of nitrous oxide from agricultural soils) are accounted for in the agriculture sector.

In 2022, Tasmania’s LULUCF sector was a net carbon sink, resulting in minus 12.51 Mt CO₂‑e. This sink offset the emissions from other sectors that had a combined contribution of 8.17 Mt CO₂‑e (Figure 18). The emissions from LULUCF decreased by 23.78 Mt CO₂-e (211.1 per cent) between 1990 and 2022. From 1990 to 2011 the sector contributed as a source of emissions but now acts as a carbon sink.

More details on the emissions and removals for the LULUCF sub-sectors and sub-categories are provided in Attachment D.

Figure 18: Tasmania's emissions from LULUCF relative to other sectors - 1990 to 2022

Greenhouse gas source and sink categories for Tasmania 2022

Table 3: Emissions for Tasmania's sectors and sub-sectors for 2022

UNFCCC emissions reporting sector and descriptions

• The STGGI provides estimates of emissions sources and sinks across five sectors. The five sectors included in the STGGI are:
  • energy
  • IPPU
  • agriculture
  • LULUCF
  • waste.
• Due to the significance of the energy sector in Tasmania, this sector is disaggregated into three sub‑sectors:
  • transport
  • direct combustion (of fuels for stationary energy)
  • electricity generation.

Table 4: Description of the UNFCCC sectors and selected sub-sectors

Summary of methodological changes to 2022 STGGI

Each year the Australian Government reviews how it calculates greenhouse gas emissions to ensure national and state inventories reflect the latest available data, improved modelling techniques, and any changes in sectoral classifications and estimation methodologies.

DCCEEW administers a quality assurance/quality control plan to maintain the integrity of the data, identify any errors and omissions, and document inventory materials and quality control activities that relate to the National Inventory Report (NIR).

The National Inventory Report 2022 was Australia’s second national inventory submission under the Paris Agreement. In line with international reporting requirements, emissions for each of the major greenhouse gases are presented as carbon dioxide equivalents using the 100-year GWPs. In accordance with Paris Agreement requirements, the latest NIR applies 100-year GWPs contained in the 2014 IPCC Fifth Assessment Report. As greenhouse gases behave differently in the atmosphere over time, converting emissions into CO₂-e allows the various gases to be compared equally. Previous NIRs submitted for the years 2013 to 2020 applied 100-year GWPs from the 2007 IPCC Fourth Assessment Report.

The Australian Government develops recalculations for the Australian inventory in line with its Inventory Improvement Plan. This plan aims to improve transparency, accuracy, completeness, consistency and comparability, with a focus on those areas where the Australian community is introducing new emissions‑reduction approaches and technologies. The improvement plan also responds to international expert reviews and changes in international practice.

This revision process includes the recalculation of historical emissions data between 1990 and 2022, nationally and for each state and territory, to ensure that the estimates of emissions are accurate, transparent, complete, consistent through time, and comparable with those produced in other countries.

In the 2021 STGGI, the Australian Government applied a new spatially-explicit modelling approach to estimate emissions from harvested native forests on public lands in Tasmania, which comprises part of the ‘forest land remaining forest land’ sub-category of the LULUCF reporting sector.

The new modelling approach improves the accuracy of estimating emissions for this sub‑category compared to the previous estate method and has now been applied to public multiple use forests in New South Wales, Queensland, Victoria and Tasmania.

The new spatially-explicit modelling method calculates the emissions from specific harvesting events, including areas affected, types of harvesting practices and vegetation species, and overlays other variables such as weather patterns, fire history, local vegetation and biomass spatial datasets. These variables affect tree growth, dead organic matter and soil composition, which contribute to the production and sequestration of emissions.

The new spatially-explicit model allows for more accurate data on harvested log volumes allocated to private native forests.

The recalculations undertaken for the 2022 STGGI have resulted in changes in Tasmania’s emissions figures across all sectors, but are particularly significant in the LULUCF sector.

As a result of these recalculations, the emissions figures in the 2022 STGGI are not directly comparable to the figures published in the STGGI reports of previous years.

Revisions in Tasmania’s emissions between the 2022 STGGI and 2021 STGGI

The recalculated data on Tasmania’s emissions show that:

• Tasmania’s emissions figure in the baseline year of 1990 is revised up 0.69 Mt CO₂-e to 19.54 Mt CO₂-e.
• Tasmania’s emissions figure in 2021 is revised up by 1.14 Mt CO₂-e to minus 3.66 Mt CO₂‑e.
• The reduction in Tasmania’s emissions figure between 1990 and 2021 is revised down from 125.5 per cent to 122.2 per cent.
• Tasmania’s emissions figures are wholly revised, resulting in Tasmania first achieving net negative emissions from 2014 onward, rather than in 2013 as reported in the 2021 STGGI.
• Tasmania has maintained net negative emissions for the nine reporting years from 2014 to 2022.

Table 5 presents a summary of the changes in Tasmania’s 1990 emissions and Table 6 presents a summary of the changes in Tasmania’s 2021 emissions by sector and energy sub‑sector reported between the 2021 STGGI and 2022 STGGI.

The tables show that the recalculations have resulted in changes across most sectors. The most significant change is concentrated in the LULUCF sector. This is replicated across the time series.

When compared with the 2021 STGGI, methodological changes in the 2022 STGGI have had different effects in LULUCF emissions data since 1990. The changes have resulted in an increase in emissions in the LULUCF sector of approximately 0.71 Mt CO₂-e in 1990 and an increase in the sink provided by the LULUCF sector of approximately minus 0.71 Mt CO_2‑e in 2021.

Table 5: Revisions to Tasmania's emissions for 1990 by sector and energy sub-sector, following calculations

Table 6: Revisions to Tasmania's emissions for 2021 by sector and energy sub-sector, following recalculations

The main methodological changes in the sub-categories that have materially contributed to the revision in Tasmania’s emissions between the 2021 STGGI and 2022 STGGI are summarised in Table 7. This information is taken from the National Inventory Report Volume I, Australian Government (2024), Department of Climate Change, Energy, the Environment and Water.

Table 7: Methodological changes and data revisions contributing to change in Tasmania's emissions between the 2021 STGGI and 2022 STGGI