Long-term projections of Australia’s future climate span a wide range of plausible outcomes. The differences in these projections arise owing to differences in greenhouse gas emissions pathways, models and natural variability in the climate. Here, we show that when considering sub-continental-scale projections of temperature, it is most important to carefully consider atmospheric composition scenario differences, whereas for rainfall, it is most important to adequately sample a wide range of climate models.

This article belongs to the collection: Model evaluation for CMIP and IPCC AR7.

Warning: Aboriginal and Torres Strait Islander people should be aware that this paper contains name(s) of deceased person(s).

This paper discusses ongoing dialogue between First Nations peoples and Western scientists in Australia about climate change. The National First Peoples Gathering on Climate Change, held in Cairns in 2021, demonstrated that building connections among First Nations peoples and Western scientists can acknowledge and respect both knowledge systems for the benefit of all. The Gathering allowed a space for creativity and recognition that climate justice is founded on respect and recognition for First Nations Peoples’ leadership and cultural authority.

This article belongs to the collection: Indigenous climate perspectives in earth system science.

We research how Australian spring rainfall is projected to change with the strength of El Niño–Southern Oscillation (ENSO), Indian Ocean Dipole (IOD) and the Southern Annular Mode (SAM) variability. Most models of CMIP6 predict stronger ENSO and SAM variability, and weaker IOD variability. Teleconnections between ENSO, IOD and SAM and Australian spring rainfall are projected to strengthen overall but details vary regionally. Mean state drying over south-west Western Australia and southern Victoria is projected to occur regardless of how modes of variability change.

This article belongs to the collection: Model evaluation for CMIP and IPCC AR7.

The variations in extreme temperatures reflect Antarctic amplification, presenting differences in both periods and regions. An obvious amplification of extreme temperature indices in East Antarctica suggests that the characteristics of the Antarctic climate could deviate from the current state.

The Deep Western Boundary Current (DWBC) is part of the great global ocean conveyor belt and is directly related to the state of global climate. Energetics analyses in ring-like shaped oceanic features in the DWBC reveal elevated energy conversion within the core area, dominated by the barotropic mean-to-eddy pathway, at an average rate of ~1 J m⁻³ day⁻¹. Calculating energy budgets and conversion rates is essential for quantifying the impact of mesoscale eddies in global circulation.

Reduced visibility due to fog significantly disrupts global air traffic, causing cancellations, delays and diversions. Using METAR, GOES-16 satellite images and ERA5 data, this study identified multiple simultaneous mechanisms influencing two fog events that strongly affected Argentine main airports. Understanding the physical mechanisms of fog is essential for better forecasting and mitigation.

Drylands are vulnerable to climate variability. This study reveals that dryland changes in Argentina are associated with variations in South Atlantic sea surface temperatures, finding that the expansion of drylands in the central region of the country, driven by increased aridity, is linked to a warming of the tropical Atlantic and cooling in the south-western Atlantic. These findings are crucial for the country, as drylands cover more than half of the territory and the economy depends on agricultural productivity.

This study evaluates the trend of long annual precipitation series in Argentina and compares the Mann–Kendall (MK) test and innovative trends analysis (ITA) method. The graphical method (ITA) has several advantages over the traditional method (MK), detecting both monotonic and non-monotonic trends, and detecting trends more sensitively by looking for smaller variations, unlike MK, which analyses series more generally. Although the MK and ITA results showed similar trend directions, with the latter methodology, the number of significant trends were greater.

Two events, one affecting north Queensland from Tropical Cyclone Jasper in December 2023 and the other in Auckland, New Zealand, in January 2023 produced record rainfall. Analyses of wind and thermal structure found that multiple factors occurring simultaneously were responsible for the extreme rainfall for both events. Similar events today would be worsened by global warming causing rising sea levels.

How variable is Australian climate and how will this change in a warmer world? The interannual variability of rainfall, temperature, pressure, moisture flux and winds is assessed using gridded observations and climate model output. Australian climate variability is typically somewhat larger than over global land. There is a small increase for 2°C global warming, in part linked to El Niño–Southern Oscillation (ENSO).

This study explores the impact of Mid-Holocene terrestrial changes, particularly the Green Sahara and African mega-lakes, on South Atlantic oceanic and atmospheric dynamics using NASA GISS E2.1-G climate model simulations. Findings highlight significant alterations in sea surface temperatures, salinity, circulation patterns and atmospheric dynamics, underscoring the critical role of vegetation and hydrology in modulating regional climate during this period. The research provides valuable insights into the interconnected nature of Earth’s climate systems, with implications for understanding past climate variability and future changes in the Southern Hemisphere.

Seasonal variations in coastal sea level associated with climate variability such as El Niño are known to influence the frequency of coastal flooding around Australia. In this article we show that, using the Australian Bureau of Meteorology’s seasonal prediction system ACCESS-S2, seasonal coastal sea level variations can be forecast accurately up to 8 months ahead of time. These seasonal forecasts will form an important component of an early warning system under development to improve community resilience to coastal flooding hazards.

The Bureau of Meteorology provides vital marine services that strongly depend on guidance from a suite of numerical weather prediction models. These models have vastly improved skill because of increased resolution, enhanced data assimilation (increasing numbers and types of observations), and improved physical parameterisations – and are verified against satellite and wave buoy observations. Compared to the legacy wave model and the European Centre for Medium-Range Weather Forecast reanalysis ERA5, the Bureau’s global wave forecast system shows increased skill.

The 2023 El Niño significantly affected weather patterns across the Indonesian Maritime Continent (IMC). Using ERA5 data, this study analyses these effects. Findings reveal that, while the northern IMC exhibited increased rainfall due to the warming of the South China Sea, the southern IMC experienced severe drought exacerbated by the positive Indian Ocean Dipole and weakened easterly winds. This study improves understanding of the diverse impact of El Niño on intraseasonal weather to enhance seasonal climate predictions over the IMC.

Record floods and record mean sea levels are occurring more often than would be expected if sea level rise was not occurring. Our results imply that higher sea-level rise scenarios are most consistent with the continuation of recent trends.