Case studies

Showing results 1 - 8 of 8
Case Study Yorta Yorta weaving

A changing climate, changing water management practices and environmental change are all impacting the way in which the Yorta Yorta people access, harvest and use one of their traditional weaving sedges (Carex tereticaulis). Most of their Country is developed; land-use activities vary from multiple crop species of wheat and corn to dairy farms.

Figure 3 Long-term climate records at Deniliquin, New South Wales, for (a) annual average maximum temperature and annual average minimum temperature; (b) the total annual rainfall (bars) with 11-year running mean

Source: Bureau of Meteorology, 2021

The weaving sedge is an ephemeral aquatic species that relies on regular seasonal watering from the Murray River, its associated waterways and rainfall. It grows throughout the area, known as Barmah. The Yorta Yorta people refer to this area as Pama.

The weaving sedge relies on multiple factors to maintain conditions that are favourable for healthy growth, such as inundation with water, soil health, climate and rainfall. A changing climate and changing water regimes are affecting the resilience of this species and, therefore, the availability of this important plant for traditional knowledge and cultural use by the Yorta Yorta people. Records show 2 important climatological events in south-east Australian history: the ‘federation drought’ at the turn of the 20th century and the ‘millennium drought’ at the turn of the 21st century (Griggs et al. 2014). They also show that a pattern of episodic flooding was evident before settlement and that cultural uses of traditional plant species were affected by these drier episodes (Griggs et al. 2014).

The impacts of low rainfall, hotter summers and a changing climate are evidence that these species are struggling to survive. This means that the Yorta Yorta people cannot harvest at this site and use the species in the same traditional setting as they had once done. Yorta Yorta Country and the weaving sedge are forced to adapt to change, and the Yorta Yorta people are forced to adapt as a result of these changes:

If this plant is no longer available on Country, then my connection to my heritage and our traditional practices have been impacted. If the plants are healthy, we can harvest the reed for weaving. If the plants are not healthy, the reeds won’t be healthy and cannot be used. This tells us that there is something wrong. This is our barometer check of healthy Country. (Denise Morgan-Bulled, 2020)

While improved water management and rainfall are seen as critical to supporting the weaving sedge, fire was recently applied to the sedge to see whether the recovery of this species was possible under adapted conditions:

To see Country burn – I felt a sense of calm; to see and feel fire – my skin felt good; to see and smell smoke – I felt I could breathe; to stand on Country – I felt strong. Country felt good that day, I felt good that day. (Sonia Cooper, 2020)

Immediately after the burn, rain fell and some parts of the forest were inaccessible, and some new growth was triggered. This project allowed the influence of fire to be investigated as an additional management tool to help recover the species. The response of the weaving sedge to fire provided cultural outcomes for traditional weaving species for the Yorta Yorta people.

Figure 4 (a and b) New tussock, Carex tereticaulis, growth through burnt Carex. (c) Unburnt C. tereticaulis new shoots after rain

Photos: S Cooper, 2020

Case Study Climate change and the Great Barrier Reef

Climate change is the most significant threat to the long-term outlook for the Great Barrier Reef region (GBRMA 2019). Although ocean temperatures are only one of several influences that pose a threat to the Reef (others include tropical cyclones, freshwater plumes and nutrient run-off from floods on land, and pests such as the crown-of-thorns starfish), they show the most clear-cut long-term trend, which is expected to continue in the future.

High marine temperatures can cause ‘bleaching’, when corals expel the symbiotic algae (zooxanthellae) living in their tissues, causing the coral to turn white. If high temperatures persist (or if other pressures further stress already bleached corals), the coral dies. Mass coral bleaching is when entire tracts or regions of a reef bleach.

Before 2016, only 2 mass coral bleaching events had occurred in the Great Barrier Reef, in 1998 and 2002. Following the event of 2016 (reported in the 2016 state of the environment report), there have been further mass bleaching events in 2017 and 2020; the 2016 and 2017 events were the first instance of mass bleaching in consecutive years. All of these bleaching events occurred during periods of abnormally high sea surface temperatures in the region. The 2016 and 2017 events were focused primarily on the northern and central Reef, leaving the southern portion largely unaffected; conversely, the 2020 event had its worst impacts in the south. The 2020 event, however, has led to comparatively limited coral mortality, with the 2020–21 summer providing favourable conditions for short-term recovery.

Sea surface temperatures have been rising consistently in the Great Barrier Reef region (BOM 2021). In February, the hottest month of the year, sea surface temperatures in the region have warmed by about 1 °C from 1900 to 2020 (see Figure 7). February 2016 was the first month on record to have a regional mean temperature above 29 °C (compared with the long-term February average of 28.0 °C), but the 2016 value of 29.1 °C was surpassed by 29.2 °C in February 2020. These very high monthly mean temperatures were associated with prolonged marine heatwaves affecting large parts of the region.

Figure 7 February sea surface temperature anomaly (1961–90 baseline) averaged over the Great Barrier Reef region, 1900–2021

The most significant long-term decline in coral has been in the northern Great Barrier Reef (see case study: Australia’s changing reefs, in the Reef recovery and management section in the Marine chapter). Hard coral cover in this region was between 20% and 30% for most of the period from when records began in the early 1980s until 2015. There was then a sharp drop to a record low of 13% in 2017. There has been a minor recovery to 17% in 2020, and then a stronger recovery to 27% in 2021, supported by relatively favourable conditions for coral recovery in the summer of 2020–21, with no major marine heatwaves or severe cyclones. Hard coral cover on the central and southern Reef shows more variability between years, with both regions dropping to record lows of 11% in 2011 as a result of the impacts of severe tropical cyclones (Yasi in the central Reef, Hamish in the south) before a rapid rebound. The central Reef reached 29% hard coral cover in 2016 before a fall to 14% in 2019 and a rebound to 26% in 2021. Other studies have found a decline of more than 50% from the 1990s to the present in the number of small, medium and large corals on the Reef (Dietzel et al. 2020). However, corals acclimatised to some extent to marine heatwaves in 2016 and 2017 (Hughes et al. 2019) – less bleaching was found for a given warming threshold in 2017 than for the same amount of warming in 2016.

Rising ocean temperatures are not the only aspect of climate change with the potential to affect coral reefs. Coral can be adversely affected by ocean acidification and rising sea levels, although the former is so far likely to have had a negligible impact on coral compared with warming temperatures (GBRMA 2019). The occurrence of freshwater plumes, and associated input of sediments and nutrients (see the Marine chapter), from flooding of coastal rivers has been relatively frequent since the 1970s compared with the past 370 years as a whole (Lough et al. 2015), but, despite their severity on land, the floods in the Townsville region in early 2019 had only a minor impact on the Reef. Water quality in the Great Barrier Reef region is routinely reported by the Queensland Government through reef water quality report cards (DES 2021).

Tropical cyclones, such as Debbie in 2017 (see case study: Severe tropical cyclone Debbie, in the Tropical cyclones section in the Extreme events chapter) and Penny in 2019, have also impacted the Reef in the past few years, but there has not been a cyclone in the past 5 years on the scale of the category 5 systems Hamish (2009) and Yasi (2011).

Coral reefs are expected to continue to decline with further global warming. Projections reported by the Intergovernmental Panel on Climate Change (IPCC 2018) indicate that coral reefs are expected to decline globally by a further 70–90% (relative to 2015) at 1.5 °C global warming, and by more than 99% at 2 °C global warming. However, there are large regional differences, and the Great Barrier Reef has, to date, recovered more rapidly after bleaching events than the larger-scale average. It is expected that the total number of tropical cyclones in the region will remain stable or decline, but that a greater proportion of the cyclones that do occur will be intense. The occurrence of extreme rainfall on land is likely to increase, even though changes to total rainfall are unclear (GBRMA & CSIRO 2021).

Case Study Sea level rise and the Torres Strait islands

Parts of the Torres Strait islands are highly vulnerable to sea level rise. A number of the islands are very low lying, and coastal inundation and erosion are significant issues even in the current climate. The most acute issues cover 2 groups of islands: the 2 alluvial islands in the top western region (Boigu and Saibai) and a number of small coral cays in the central part of the Torres Strait islands.

In the top western islands, there have been several inundation events since 2005. In 2011, during a strong La Niña event, some inhabited areas of Saibai were inundated to a depth of up to 0.5 metres (Systems Engineering Australia 2011). Some of the central coral cays have experienced significant coastal erosion. In addition to direct impacts on inhabited areas of the islands, these events threaten impacts on graves and other significant cultural sites, as well as saltwater intrusion into landfills, wastewater treatment sites and groundwater. Although tropical cyclones are relatively rare in the islands compared with areas further south in northern Queensland, storm surge associated with tropical cyclones is another potential risk.

Observed rates of sea level rise in the region over the period 1993–2010 were about 6 millimetres per year, somewhat greater than the global average of 3–3.5 millimetres per year and consistent with a broader pattern of increased sea level rise in the western tropical Pacific over this period. It is as yet unclear what contribution, if any, variability in the behaviour of the El Niño–Southern Oscillation (particularly the predominance of La Niña in the late 2000s and early 2010s) has made to this locally increased sea level rise, and whether it is likely to be sustained. Planning in the islands is widely based on projected sea level rise of 0.8 metres by 2100 (Green et al. 2010, Suppiah et al. 2011, TSRA 2014, Rainbird 2016).

Significant works to adapt to sea level rise are already taking place. New seawalls have been completed on Saibai and Boigu islands, replacing earlier community-built seawalls that had previously failed, as well as on Poruma Island in the central coral cay region. Further seawalls are in the planning stage. It is expected that, with such infrastructure works, existing communities will remain viable for at least several decades. Relocation of communities to other islands is regarded as a highly culturally disruptive option and would be considered only as a last resort.

Case Study The 2017−19 Australian drought

Sources: BOM (2020a), Trewin et al. (2021)

The period from 2017 to 2019 saw severe drought affecting many parts of Australia. The most significant rainfall deficiencies occurred in the northern part of the Murray–Darling Basin, in northern New South Wales and southern Queensland. Dry conditions began in these regions in late 2016, and 2017 and 2018 were both significantly drier than normal in these areas. Other areas that also began to experience significant multiyear drought during this period were Gippsland and eastern Tasmania, and parts of southern Western Australia.

In 2019, the dry conditions intensified and expanded to cover many parts of the country. The most acute dry conditions were again focused on the northern Murray–Darling Basin, where some areas on both sides of the New South Wales – Queensland border had annual rainfall in 2019 that was 70–80% below normal, and more than 40% below previous record lows. As an example, rainfall averaged over the Gwydir catchment in 2019 was 176 millimetres (mm), 74% below normal, and 49% below the previous record of 348 mm set in 1902. It was also exceptionally dry over much of Australia’s interior (where numerous locations had less than 30 mm for the year) and in parts of coastal New South Wales between the Hunter region and the Queensland border. The 2018−19 and 2019−20 wet seasons also had well-below-average rainfall over many tropical parts of Western Australia and the Northern Territory.

Averaged over the country, 2019 was Australia’s driest year on record, surpassing the previous record set in 1902. New South Wales and South Australia also had their driest years on record, with South Australia having a state average rainfall below 100 mm for the first time. A strong positive phase of the Indian Ocean Dipole was a major contributor to 2019’s dry conditions, especially in the second half of the year.

It was the driest 3-year period on record for the Murray–Darling Basin, with a Basin average of 917 mm (37% below normal), breaking the previous record of 1,037 mm set in 1965−67. The dry conditions were particularly concentrated in the cooler months of the year, which exacerbated the impacts on water availability and agriculture. The April–September period of 2017, 2018 and 2019 all ranked among the 10 driest on record for New South Wales.

The most significant multiyear droughts in the region were 1895−1903, 1937−46 and 1997−09 (the millennium drought). The recent drought did not persist as long as those events, but was more intense over a 2−3-year period. The millennium drought was most severe in the southern Murray–Darling Basin (and in areas of eastern Queensland and southern Victoria outside the Basin). The northern Basin was less severely affected, whereas in 2017−19 the southern Basin was less severely affected than the north. Snow depth in the Australian Alps, which is important for spring inflows into the southern Basin, was also above average in all 3 years, partly because of a lack of rain events to cause melting during the snow season.

The most acute phase of the widespread drought eased during 2020, which saw average to above-average rains over most of eastern Australia from February onwards. Some locally dry areas remained, particularly in the south-east quarter of Queensland, and many parts of southern Western Australia had another dry year.

Figure 12 Australian rainfall deciles for (a) 2019; (b) 2017−19

Major impacts on water resources

The drought severely affected water availability in many areas. Water storage levels in the northern Murray–Darling Basin dropped to 5.4% in mid-January 2020 (see Figure 5, in the Dams and reservoirs section in the Inland water chapter), and many individual storages were below 10% of capacity. A gradual recovery began from February 2020, but levels did not exceed 30% until floods in March 2021. Many rivers in the region had record low flows or ceased to flow altogether, contributing to significant environmental impacts, including large-scale fish deaths in the Darling River in early 2019. At the peak of the drought in late 2019, numerous towns ran out of conventional water supplies and required water to be trucked in.

The drought also had a substantial impact on agriculture, especially in 2019. Crop production in New South Wales and Queensland in 2019 was about 70% below the 10-year average, and the national sheep flock was at its smallest since 1905.

Did climate change contribute to the drought?

No formal attribution study has been carried out on the drought as a whole. A study investigating the impact of climate change on various factors contributing to the fire weather conditions in Australia in 2019−20 found no attributable signal of anthropogenic climate change contributing to the dry conditions of July–December 2019, although it did find an attributable signal for other aspects of fire weather (van Oldenborgh et al. 2021).

Over the worst-affected areas of the northern Murray–Darling Basin, there is not a clear-cut downward long-term trend in rainfall. Rainfall since 2000, as in much of eastern Australia, has been broadly comparable with that in the first half of the 20th century, although lower than that between the 1950s and the 1990s. There is some evidence of a shift in rainfall away from the cool season and towards the warm season, which is consistent with the very low cool-season rainfall in each of 2017, 2018 and 2019.

Much of south-western and south-eastern Australia has experienced a substantial decline in rainfall in the past few decades, especially in the cool season (see Rainfall and snow). The very dry conditions in much of southern Western Australia in 2018 and 2019 were consistent with this, although some other areas, such as south-western and central Victoria, were less affected by the 2017−19 drought than regions further north.

One clear-cut climate change signal was that of very high temperatures, particularly during the day and in the warmer months. The years 2019 and 2018 were the 2 warmest years on record averaged over the Murray–Darling Basin, and 2017 was fourth warmest; the 3-year period was 1.65 °C above the 1961−90 average. The high temperatures increased evaporative demand and created additional stress on ecosystems and crops. However, the dry conditions also contributed to frosts, especially in 2017 when some parts of southern inland New South Wales had their coldest average winter minimum temperatures on record. There were also damaging frosts in September 2018 and 2019.

Case Study The 2019−20 Australian bushfire season

Sources: VBRC (2009), BOM (2020c), van Oldenborgh et al. (2021)

The 2019−20 Australian bushfire season was exceptional in modern times. The first major fires occurred in north-eastern New South Wales and south-eastern Queensland in early September 2019. Fire was present in the temperate forests of eastern Australia almost continuously from September 2019 to February 2020. In spring 2019, the major focus of fire activity was in northern New South Wales and southern Queensland; from late November, it shifted to central and southern New South Wales, eastern Victoria and the Australian Capital Territory. Destructive fires also affected Kangaroo Island and the Adelaide Hills in South Australia. The most acute phase of the season ended in the second week of February after widespread heavy rain, although some fires continued to burn within containment lines for several weeks after that.

An estimated 5.8 million hectares of temperate forest was burnt, easily the largest area in a season since detailed records have been kept – an unprecedented 23% of temperate forests in south-east Australia was burnt. The burnt area extended almost unbroken from Bundanoon in New South Wales to Bairnsdale in Victoria, a distance of more than 500 kilometres (see the Extreme events chapter).

Thirty-three lives were lost directly, and many more are likely to have been lost indirectly as a result of smoke pollution. More than 3,000 homes were destroyed, and direct and indirect economic losses were estimated to have exceeded $10 billion. There were also major impacts on biodiversity, with many plant and animal communities severely affected (see the Biodiversity chapter).

Weather conditions contributing to the fires

Severe drought affected much of Australia in 2019 (see case study: The 2017−19 Australian drought). Most of the fire-affected areas had less than half their average rainfall in the second half of 2019. It was the driest July–December period on record for most of the eastern ranges of New South Wales, and adjacent areas of southern Queensland and eastern Victoria. The dry conditions led to unusually dry fuels, while the almost total absence of widespread significant rain events from September onwards meant that many fires, once established, burned for several weeks or months. This meant that, on individual days of extreme fire weather, there was already substantial active fire in the landscape in addition to any new ignitions that might occur. (In contrast, on Black Saturday in February 2009, all but one of the major fires started on that day.)

Extreme fire weather in the coastal ranges of eastern Australia is typically associated with strong westerly to north-westerly winds, bringing dry, warm air from inland Australia. Fires can move very rapidly under such conditions, and most loss of life and property occurs on such days. These winds are common in winter and spring, but become uncommon in a normal season from late spring onwards, especially north of Sydney. Some of the most extreme fire weather episodes were in the second week of November in northern New South Wales, when at one stage 17 emergency warnings were current, and on 30–31 December in southern New South Wales and eastern Victoria, when some fires moved more than 50 kilometres in 24 hours. There were significant losses in both events.

In 2019, there was a strong negative phase of the Southern Annular Mode (SAM; see Other climate influences), which contributed to westerly wind events being more frequent and lasting further into the season than would occur in a normal year. The negative SAM phase was, in turn, linked to an abrupt warming of the upper atmosphere in Antarctica in September, which also contributed to an abnormally small Antarctic ozone hole (see the Antarctica chapter) (Lim et al. 2021). November was an unusually windy month over south-eastern Australia, and monthly average humidity was at record lows in many parts of eastern New South Wales in November and December.

The most commonly used indicator of fire weather is the Forest Fire Danger Index (FFDI), which combines dryness, wind and temperature. Numerous FFDI-based measures in 2019 were far beyond previous records. The FFDI reached more than 100 (catastrophic) in northern New South Wales as early as 6 September. In total, there were 21 days during spring 2019 when the FFDI averaged over north-eastern New South Wales reached 25 (very high) or above, far exceeding the previous record of 11 days and the long-term average of 2 days. Averaged over the full period, the FFDI for September–December 2019 was the highest on record over almost all of New South Wales and Queensland, as well as in most of South Australia except for the south-east, and in eastern Victoria.

Figure 14 Deciles of aggregated FFDI for September–December 2019, showing the highest values on record for most of the areas affected by fires

Source: BOM (2019)

Did climate change contribute to the fire weather conditions?

Fire weather conditions combine temperature, humidity, wind and antecedent moisture (or its absence). A study of the fire weather conditions in 2019−20 found that anthropogenic climate change has induced a higher weather-related risk of such an extreme fire season, driven primarily by increases in temperature (van Oldenborgh et al. 2021). No attributable relationship was found between climate change and the risk of droughts similar to that of July−December 2019. These results roughly mirror those of a similar study into the weather conditions underlying fires in central Queensland in spring 2018 (Lewis et al. 2020).

Case Study COVID-19, greenhouse gas emissions and climate

The COVID-19 pandemic led to widespread shutdowns of activity in Australia and elsewhere during 2020. This contributed to sharp reductions in greenhouse gas emissions in most countries, as well as reduced emissions of other substances.

Preliminary estimates indicate that global greenhouse gas emissions arising from the consumption of fossil fuels in 2020 decreased by 7% from 2019 values (Friedlingstein et al. 2020). At the peak of global shutdowns in early April 2020, estimated reductions in global greenhouse gas emissions were 17% (about half from surface transport), and individual countries had peak reductions of 26% (Le Quere et al. 2020).

In Australia, reductions in emissions were slightly below the global average. There was a 5.0% decrease for 2020 compared with 2019, with the June and September quarters 6–8% below the corresponding quarters of 2019. This reflects the fact that, outside Victoria, COVID-19-related restrictions on activity in Australia in 2020 were less severe and prolonged than in many other countries.

The largest sectoral decrease was 12.1% for transport, including 11.5% from petrol consumption and 50.9% from jet fuel (Figure 20).

Figure 20 Changes from 2019 to 2020 in Australian greenhouse gas emissions, by sector

Source: DISER (2020b)

Not all the reduced emissions in 2020 were related to the pandemic – for example, there was a 2.5% decrease in agricultural emissions between 2018–19 and 2019–20, which largely reflects the impacts of drought conditions during 2019. Agricultural emissions increased again in the second half of 2020, with the year to December 2020 having no change from the year to December 2019. Emissions from electricity generation were down by 4.9%, but this largely reflects an increased share of renewable energy, with only small changes in total electricity demand.

At a global scale, the impact of 2020’s reduced emissions on temperatures is expected to be negligible. Modelling has found that the reduced emissions are expected to lead to cooling of 0.01 °C (±0.005 °C) by 2030 relative to a scenario where they did not occur (Forster et al. 2020). In the short term, the pandemic led to slight increases in global temperatures during 2020 (Gettelman et al. 2020), as reduced emissions of aerosols and particulates more than offset reduced greenhouse gas emissions (particularly in heavily industrialised land areas of the Northern Hemisphere). However, these aerosol effects are expected to be short-lived compared with the ongoing impacts of changes in greenhouse gas emissions.

Case Study 2021 First Nation Peoples Statement on Climate Change

We, the participants attending the Gathering, acknowledge the voices of the Gimuy Walubarra Yidinji and Yirraganydji, whose lands we meet upon in 2021.

Building on the 2018 statement from First Peoples on Yorta Yorta land, we as First Nation Peoples of Australia recognise that overwhelmingly scientific and traditional knowledge is demanding immediate action against the threats of climate change. When Country is healthy, we are healthy.

Our knowledge systems are interconnected with our environment and it relies on the health of Country. This knowledge is held by our Elders and passed on to the next generation. Solutions to climate change can be found in the landscapes and within our knowledge systems. Aboriginal and Torres Strait Islander peoples have the tools, knowledge, and practices to effectively contribute to the fight against climate change.

We have lived sustainably in Australia for over 100,000 years. First Nations people of Australia contribute the least to climate change, yet the impacts of climate change are affecting us most severely.

We at the Gathering are calling for the following:

  • A commitment from Federal Government to financially support an annual First Nations-led dialogue on climate change. The annual dialogue should be a place where Aboriginal and Torres Strait Islanders can discuss the changing climate in their communities and is a valuable input to inform policy at all levels.
  • A commitment for federal-level funding for an Indigenous-led climate action hub, which would fund both Indigenous-led mitigation and adaptation climate change projects. These projects could focus on:
    • −Domestic emissions reductions through enabling reliable renewable energy supply to off grid communities, Indigenous-led nature-based solutions.
    • −Indigenous-led adaptation planning for communities and the recording and transmission of knowledges and experiences across the country.
  • The establishment of a Torres Strait Island taskforce, led by First Nations peoples of the region, to drive critical and tangible climate change solutions for island communities under present and immediate threat.
  • We call on all Australians to join us in acting on climate change and in protecting the environment. To work collaboratively with us, learn our laws and our ways and respect our knowledges to find solutions together to combat climate change.
  • Climate action that links all levels of government so our people and communities can work collaboratively in an Indigenous-led fight against climate change.
  • The right to manage Country. First Nations peoples must be involved in the national dialogue about climate change and be engaged on any decision that impacts us and our Country. We call for these rights to be respected and observed on an international, national, state and local level. Our knowledge must be included in climate management frameworks.
  • To look beyond ourselves, to include flora and fauna in climate planning and climate management frameworks so the plants and animals that support us can be represented. We are seeing changes in the environment and the declining health of Country and people. We can see our native flora and fauna are suffering and the conditions of our lands, waters, seas and skies declining. For some of our people it is an emergency because the climate crisis has already caused widespread damage.

Our connection to Country represents climate science developed over countless generations, listen to us, work with us and together we can enact a change that will shape our future for all Australians.

Case Study Talking in Arrernte about climate change

During 2014–15, the Ltyentye Apurte Central Land Council Rangers and CSIRO scientists shared knowledge about climate change to improve understanding and regional records. Ltyentye Apurte Rangers started by assembling local data, including photographs and recollections, to construct their own weather and climate timeline (Figure 22). They compared this timeline with scientific weather and climate data (Figure 23), showing a strong alignment that allowed the rangers to see trends that had not been obvious before:

Timeline of major events, like floods, fires, droughts and other things people could remember … showed the knowledge of local people and how the events aligned with and matched weather patterns with those recorded with scientists. We … observed notable changes in those graphs and records, showed more days over 40 °C, also bigger floods happening in later times. (Ltyentye Apurte Ranger Coordinator, 2015)

Figure 22 Ltyentye Apurte Rangers and CSIRO scientists looking at the 2 timelines together

Photo: Fiona Walsh

Figure 23 Days above above 40 °C by year, 1942–2019; dark bars highlight years with more than 20 such days

Source: Bureau of Meteorology

Arrernte Elders also provided information about changes on Country, summarised by the ranger coordinator as:

Indigenous people of central Australia have been carers for Country for generations, passing on important cultural knowledge for land management practices. Over time, our people have noticed changes in the weather and seasons. Seasons seem more mixed up. Bush tucker is not fruiting or flowering at the right time of year.

The rangers were very interested in helping Arrernte people understand more – one of the rangers said, ‘I’m going learn this, learn all this, and put it in Arrernte so my mob can understand it.’

The scientists and the rangers worked together to produce a book and a slideshow in English. The rangers then presented this to Arrernte community audiences, speaking in Arrernte. People were grateful to hear about it in their own language, commenting that they had seen a lot about climate change on television, but had not understood what it was about before. Many impacts and potential solutions were also identified, including changes to houses, increased shade, and greater access to the swimming pool and cool buildings.

The main road to the Ltyentye Apurte community where the rangers live and work is being threatened by an erosion gully that is rapidly expanding as a result of large rainfall events. These events are increasing in intensity and frequency due to climate change. Rangers undertook activities and co-learning about erosion, in collaboration with scientists and practitioners, and established a trial of a new way of managing erosion. They built a set of control banks along the contour in 1 small catchment. However, the trial was compromised by inconsistent management of free-ranging horses, which trampled the control banks and led to bank breaching during heavy rains. Rebuilding of the control banks is currently impeded by loss of access to necessary resources.

The problem of climate change for Aboriginal people in central Australia is enormous. In the words of Central Land Council Chair Sammy Wilson during the 2019 Global Climate Strike (Central Land Council 2019):

I call on them to spare a thought for Aboriginal people out bush who may not be able to travel to the strikes but who are already suffering most during our hotter, longer and drier summers … I am dreading another summer like the last one because it is especially tough on our old and sick people who live in overcrowded, poor quality houses. Sammy Wilson, Central Land Council Chair