CSIRO has unveiled the 2024 State of the Climate report, which found Australia’s weather and climate have continued to change, with increased extreme heat events, longer fire seasons, more intense heavy rainfall and sea level rises.
The report draws on the latest national and international climate research, monitoring and projection information to describe changes and long-term trends in Australia’s climate, and is prepared every two years in collaboration between CSIRO and the Bureau of Meteorology.
Scientists have found that the oceans around Australia are continuing to warm and Increases in carbon dioxide in the atmosphere are making the oceans more acidic, mainly in the south of Australia.
CSIRO Research Manager Dr Jaci Brown said ocean warming has contributed to longer and more frequent marine heatwaves. The highest average sea surface temperature on record occurred in 2022.
“Increases in temperature have contributed to significant impacts on marine habitats, species and ecosystem health, such as the most recent mass coral bleaching event on the Great Barrier Reef this year,” Dr Brown said.
“Rising sea levels around Australia are increasing the risk of inundation and damage to coastal infrastructure and communities.
“Global mean sea level is increasing, having risen by around 22cm since 1900. Half of this rise has occurred since 1970.
“The rates of sea level rise vary across the Australian region, with the largest increases in the north and south-east of the Australian continent.”
The amount of greenhouse gases in the atmosphere continues to increase, contributing to climate change, with 2023 the warmest year on record globally.
Dr Karl Braganza, Climate Services Manager at the Bureau of Meteorology, said Australia is continuing to warm, with eight of the nine warmest years on record occurring since 2013.
“This warming has led to an increase in extreme fire weather and longer fire seasons across large parts of the country,” Dr Braganza said.
The report describes the shift toward drier conditions across the southwest and southeast from April to October 2024. Reduced rainfall in southwest Australia now seems to be a permanent feature of the climate.
“The lower rainfall in the cooler months is leading to lower average streamflow in those regions, which can impact soil moisture and water storage levels and increase the risk of drought. Droughts this century have been significantly hotter than those in the past,” Dr Braganza said.
“However, when heavy rainfall events occur, they are becoming more intense, with an increase of around ten per cent or more in some regions.
“The largest increases are in the north of the country, with seven of the ten wettest wet seasons since 1998 occurring in northern Australia.”
Although Australian emissions have declined since 2005, the country is projected to continue warming over the coming decades, with more extremely hot days and fewer extremely cool days.
The rate of emissions decline will need to accelerate from now to meet Australia’s 2030 emissions targets.
State of the Climate 2024 is the eighth report in a series published every two years by CSIRO and the Bureau of Meteorology. The findings highlight the importance of ongoing monitoring and help to inform and manage climate risk.
The 2024 report can be found on the CSIRO and Bureau of Meteorology websites.
Featured image: CSIRO
