As of December 2022, the highest recorded temperature in Australia was at Onslow Airport in Western Australia, where the temperature was **** degrees Celsius. This was matched by the highest temperature recorded at Oodnadatta Airport, South Australia, in 1960. What is causing increasing temperatures? The annual mean temperature deviation in the country has increased over the past century. In 2024, the annual national mean temperature was **** degrees Celsius above average. Climate experts agree that the major climate driver responsible for the heat experienced in Australia was a positive Indian Ocean Dipole (IOD). This is where sea surface temperatures are cooler in the eastern half of the Indian Ocean than the western half. The discrepancy in temperatures led to drier, warmer conditions across Australia. Global warming due to greenhouse gas emissions has been linked to the warming of sea surface temperatures and the IOD. Social change While the topic of global warming is undoubtedly controversial, many people perceive global warming as influencing Australia’s climate. In 2023, around ** percent of Australians believed climate change was occurring. Furthermore, around **** of Australians agreed that their government was not doing enough in terms of climate change action.

In 2024, the mean temperature deviation in Australia was 1.46 degrees Celsius higher than the reference value for that year, indicating a positive anomaly. Over the course of the last century, mean temperature anomaly measurements in Australia have exhibited an overall increasing trend. Temperature trending upwards Global land temperature anomalies have been fluctuating since the start of their measurement but show an overall upward tendency. Australian mean temperatures have followed this trend and continued to rise as well. Considered the driest inhabited continent on earth, this has severe consequences for the country. In particular, the south of Australia is predicted to become susceptible to drought, which could lead to an increase in bushfires as well. The highest temperatures recorded in Australia as of 2022 were measured in South Australia and Western Australia, both exceeding 50 degrees. The 2019/2020 bushfire season Already prone to wildfires due to its dry climate, the change in temperature has made Australia even more vulnerable to an increase in bushfires. One of the worst wildfires in Australia, and on a global level as well, happened during the 2019/2020 bushfire season. The combination of the hottest days and the lowest annual mean rainfall in 20 years resulted in a destruction of 12.5 million acres. New South Wales was the region with the largest area burned by bushfires in that year, a major part of which was conservation land.

Temperature in Australia increased to 22.32 celsius in 2023 from 21.93 celsius in 2022. This dataset includes a chart with historical data for Australia Average Temperature.

In 2023, the observed annual average mean temperature in Australia reached 22.32 degrees Celsius. Overall, the annual average temperature had increased compared to the temperature reported for 1901. Impact of climate change The rising temperatures in Australia are a prime example of global climate change. As a dry country, peak temperatures and drought pose significant environmental threats to Australia, leading to water shortages and an increase in bushfires. Western and South Australia reported the highest temperatures measured in the country, with record high temperatures of over 50°C in 2022. Australia’s emission sources While Australia has pledged its commitment to the Paris Climate Agreement, it still relies economically on a few high greenhouse gas emitting sectors, such as the mining and energy sectors. Australia’s current leading source of greenhouse gas emissions is the generation of electricity, and black coal is still a dominant source for its total energy production. One of the future challenges of the country will thus be to find a balance between economic security and the mitigation of environmental impact.

In 2023, the observed annual average maximum temperature in Australia reached 29.67 degrees Celsius. Overall, the annual average maximum temperature had increased compared to the temperature reported for 1901.

Given the rising frequency of thermal extremes (heatwaves and cold snaps) due to climate change, comprehending how a plant’s origin affects its thermal tolerance breadth becomes vital. We studied juvenile plants from three biomes: temperate coastal rainforest, desert, and alpine. In controlled settings, plants underwent hot days and cold nights in a factorial design to examine thermal tolerance acclimation. We assessed thermal thresholds (Tcrit-hot and Tcrit-cold) and thermal tolerance breadth (TTB). We hypothesised that: 1) desert species would show the highest heat tolerance, alpine the greatest cold tolerance, with temperate species intermediate; 2) all species would increase heat tolerance post hot days and cold tolerance after cold nights; 3) combined exposure would broaden TTB more than individual conditions, especially in the desert and alpine species. We found that biome responses were minor compared to the responses to the extreme temperature treatments. All plants increased thermal tolerance in response to hot 40°C days (Tcrit-hot increased by ~3.5°C) but there was minimal change in Tcrit-cold in response to the cold -2°C nights. In contrast, when exposed to both hot days and cold nights, on average plants exhibited an antagonistic response in TTB, where cold tolerance decreased and heat tolerance was reduced, and so we did not see the bi-directional expansion we hypothesised. There was, however, considerable variation among species in these responses. As climate change intensifies, plant communities, especially in transitional seasons, will regularly face such temperature swings. Our results shed light on potential plant responses under these extremes, emphasizing the need for deeper species-specific thermal acclimation insights, ultimately guiding conservation efforts. # Acclimation of thermal tolerance in juvenile plants from three biomes is suppressed when extremes co-occur https://doi.org/10.5061/dryad.cz8w9gjbg ## Thermal tolerance data This Excel file contains the data from the paper 'Acclimation of thermal tolerance in juvenile plants from three biomes is suppressed when extremes co-occur' Test Whether the metric was tcrit hot, tcrit cold, or thermal tolerance breadth (TTB) ID Not a true ID, but gives you the date, block, plate a or b, and what test it was Block Replicate group of species from 1-5. Smaller plants were in blocks 2 and 4 sp Species name combined with what treatment it went in Plant_ID ID that tells you the block number, species, and treatment Species Species name Measurement_Day If plants were measured on day 3 or day 5 Biome Which biome: temperate, desert or alpine Treatment The treatment type: warming, cooling, combination or control Warming Either yes or no: e.g. control would be no but heatwave would be yes Cooling Either yes or no: e.g, control would be no, and heatwave would be no PAMID The area of interest recorded on the PAM to get F0 values (not unique and not useful in analysis at this point) Tcrit Derived from tcrit extraction script in R Tmax Derived from tcrit extraction script in R NT Calculated from thermocouple temperature output when an exothermic reaction occurs (release of heat during ice formation) and tells you the time/temp when ice formed TTB Tcrit hot minus tcrit cold gives you the thermal tolerance breadth (TTB) Growth_Form Type of growth form the plants are Delta_Tcrit Tcrit of treatment minus the control treatment Type The treatment combination type: warming, cooling, combination or control NA = failed tcrit or missing data due to error Title: Methods for Assessing Thermal Tolerance in Plants from Different Australian Biomes Summary: This study compared the responses of plants from temperate rainforest, alpine, and desert biomes in Australia to hot days and cold nights using temperature-dependent increases in chlorophyll a fluorescence. For each biome, eight species were selected based on seed availability and family representation. Seeds were obtained from conservation seed banks, sown, and grown under common conditions in glasshouses. Some species were purchased from nurseries. A fully factorial experimental design was used with three biomes, eight species per biome, five replicates, and four temperature treatments (control, hot days, cold nights, and a combination of hot days and cold nights). Experiments were conducted in growth chambers, and plants were exposed to the temperature regimes for five days. Leaf temperatures were monitored using thermocouples. Thermal tolerance assays were performed on days three and five of the experiment using Maxi Pulse Amplitude Modulating (PAM) systems. Leaf discs were placed on Peltier plates and subjected to cooling (-25°C) and heating (65°C) ramps. The critical temperatures during heating (Tcrit-hot) and cooling (Tcrit-cold) were defined as the breakpoint between the slow and fast-rise phases of basal fluorescence.

One-dimensional (1D) and three-dimensional (3D) thermal modelling indicates that the highest geothermal anomalies in the Perth Basin occur in the Coomallo and Beermullah Troughs, Bookara Shelf, and north of Moora township. The modelled temperatures and recorded temperatures are up to 154 and 150C at 4 km, respectively. These are based on temperatures in 253 petroleum wells, 1D modelling of 162 wells, and temperature simulation directly from a 3D geology model centred on the Dongara to Eneabba region (which the earlier 1D modelling indicated as having the highest simulated and recorded temperatures within the Perth Basin).

Our study had a glasshouse and a field component. The glasshouse study provided the opportunity to better control water availability, while the field study provided observations of tall trees in the field. The glasshouse experiment examined responses to a five-day heatwave under controlled conditions, with a direct comparison of well-watered and droughted conditions using a gradual, moderate drought stress. Four treatments include: C, control; D, drought; C+HW, control + heatwave; D+HW, drought + heatwave. In the field, we took advantage of naturally-occurring extreme heatwaves to compare in situ responses of urban trees in Sydney, Australia during the hottest and driest year on record (2019). We investigated if there is evidence for decoupling of stomatal conductance (gs) from net photosynthesis (Anet) in 26 different broadleaf tree or shrub species (n=4-8 trees per species) by measuring leaf gas exchange on hot days (maximum air temperature >40 °C). For more details, see associated publication in Global Change Biology (link below).