The datasets created to produce the emergency mapping support products which contributed to fulfilling GA's arrangements in supporting the outcomes sought by the Australian Government during disaster events.

"History provides a limited picture of what can happen from tropical cyclones (TCs). Take the example of Port Hedland or Townsville, with limited numbers of close TC impacts, especially in recent decades, where many communities have gone through rapid growth. How could emergency services in these towns prepare adequately for a major TC strike with no recent experience? How do they know if they have sufficient resources? Will they need to call in resources from other regions or further afield? In this presentation, we will discuss two parts of this problem – developing plausible scenarios of TCs for use in exercises and then evaluating the impacts of a selection of these events to guide planning and response actions for emergency services. GA’s Tropical Cyclone Hazard Assessment (TCHA) provides the backbone of impact scenario modelling – a stochastic catalogue of 10,000 years of plausible TC events that users can delve into. We connect the scenarios to our extensive built environment data collection and the corresponding vulnerability modelling capability to deliver tangible information on the impacts that as-yet unseen events could deliver to communities around our northern coastline.

The first step in understanding risk is understanding the hazard. This means knowing the likelihood of the hazard event and its intensity. During 2018, Geoscience Australia updated the Tropical Cyclone Hazard Assessment (TCHA) to better calculate the likelihood of tropical cyclones in Australia.

Tropical cyclones can significantly impact mangrove forests, with some recovering rapidly, whilst others may change permanently. Inconsistent approaches to quantifying these impacts limit the capacity to identify patterns of damage and recovery across landscapes and cyclone categories. Understanding these patterns is critical as the changing frequency and intensity of cyclones and compounding effects of climate change, particularly sea-level rise, threaten mangroves and their ecosystem services. Improvements in Earth observation data, particularly satellite-based sensors and datacube environments, have enhanced capacity to classify time-series data and advanced landscape monitoring. Using the Landsat archive within Digital Earth Australia to monitor annual changes in canopy cover and extent, this study aims to quantify and classify immediate and long-term impacts of category 3–5 cyclones for mangroves in Australia. Closed canopy mangrove forests experienced the greatest immediate impact (loss of canopy cover).Most immediate impacts were minor, implying limited immediate mortality. Impacts varied spatially, reflecting proximity to exposed coastlines, cyclone track and forest structure (height, density, condition and species). Recovery was evident across all cyclones, although some areas exhibited permanent damage. Understanding the impacts and characteristics of vulnerable and resilient forests is crucial for managers tasked with protecting mangroves and their services as the climate changes. <b>Citation:</b> Asbridge E, Krause C, Lucas R, et al. Characterising the short- and long-term impacts of tropical cyclones on mangroves using the Landsat archive. Cambridge Prisms: Coastal Futures. 2025;3:e4. doi:10.1017/cft.2024.19