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2. Priorities for Wind-Waves Research

Author

Greenslade, Diana, Hemer, Mark, Babanin, Alex, Lowe, Ryan, Turner, Ian, Power, Hannah, Young, Ian, Ierodiaconou, Daniel, Hibbert, Greg, Williams, Greg, Aijaz, Saima, Albuquerque, João, Allen, Stewart, Banner, Michael, Branson, Paul, Buchan, Steve, Burton, Andrew, Bye, John, Cartwright, Nick, Chabchoub, Amin, Colberg, Frank, Contardo, Stephanie, Dufois, Francois, Earl-Spurr, Craig, Farr, David, Goodwin, Ian, Gunson, Jim, Hansen, Jeff, Hanslow, David, Harley, Mitchell, Hetzel, Yasha, Hoeke, Ron, Jones, Nicole, Kinsela, Michael, Liu, Qingxiang, Makarynskyy, Oleg, Marcollo, Hayden, Mazaheri, Said, McConochie, Jason, Millar, Grant, Moltmann, Tim, Moodie, Neal, Morim, Joao, Morison, Russel, Orszaghova, Jana, Pattiaratchi, Charitha, Pomeroy, Andrew, Proctor, Roger, Provis, David, Reef, Ruth, Rijnsdorp, Dirk, Rutherford, Martin, Schulz, Eric, Shayer, Jake, Splinter, Kristen, Steinberg, Craig, Strauss, Darrell, Stuart, Greg, Symonds, Graham, Tarbath, Karina, Taylor, Daniel, Taylor, James, Thotagamuwage, Darshani, Toffoli, Alessandro, Valizadeh, Alireza, van Hazel, Jonathan, da Silva, Guilherme Vieira, Wandres, Moritz, Whittaker, Colin, Williams, David, Winter, Gundula, Xu, Jiangtao, Zhong, Aihong, and Zieger, Stefan

Published
2020

3. 15 Priorities for Wind-Waves Research : An Australian Perspective

Author

Greenslade, Diana, Hemer, Mark, Babanin, Alex, Lowe, Ryan, Turner, Ian, Power, Hannah, Young, Ian, Ierodiaconou, Daniel, Hibbert, Greg, Williams, Greg, Aijaz, Saima, Albuquerque, João, Allen, Stewart, Banner, Michael, Branson, Paul, Buchan, Steve, Burton, Andrew, Bye, John, Cartwright, Nick, Chabchoub, Amin, Colberg, Frank, Contardo, Stephanie, Dufois, Francois, Earl-Spurr, Craig, Farr, David, Goodwin, Ian, Gunson, Jim, Hansen, Jeff, Hanslow, David, Harley, Mitchell, Hetzel, Yasha, Hoeke, Ron, Jones, Nicole, Kinsela, Michael, Liu, Qingxiang, Makarynskyy, Oleg, Marcollo, Hayden, Mazaheri, Said, McConochie, Jason, Millar, Grant, Moltmann, Tim, Moodie, Neal, Morim, Joao, Morison, Russel, Orszaghova, Jana, Pattiaratchi, Charitha, Pomeroy, Andrew, Proctor, Roger, Provis, David, Reef, Ruth, Rijnsdorp, Dirk, Rutherford, Martin, Schulz, Eric, Shayer, Jake, Splinter, Kristen, Steinberg, Craig, Strauss, Darrell, Stuart, Greg, Symonds, Graham, Tarbath, Karina, Taylor, Daniel, Taylor, James, Thotagamuwage, Darshani, Toffoli, Alessandro, Valizadeh, Alireza, van Hazel, Jonathan, da Silva, Guilherme Vieira, Wandres, Moritz, Whittaker, Colin, Williams, David, Winter, Gundula, Xu, Jiangtao, Zhong, Aihong, and Zieger, Stefan

Published
2020

8. A National-Scale Coastal Storm Hazards Early Warning System for Australia

Author

Turner, Ian L., primary, Leaman, Christopher K., additional, Harley, Mitchell D., additional, Thran, Mandi C., additional, David, Daniel R., additional, Splinter, Kristen D., additional, Hansen, Jeff, additional, Cuttler, Michael V. W., additional, Greenslade, Diana J.M., additional, Zieger, Stefan, additional, and Lowe, Ryan, additional

Published
2024
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9. A MULTI-SCALE COASTAL STORM HAZARDS EARLY WARNING SYSTEM FOR AUSTRALIA

Author

Leaman, Christopher, primary, Thran, Mani, additional, David, Daniel, additional, Turner, Ian, additional, Harley, Mitchell, additional, Matheen, Nashwan, additional, Cuttler, Michael, additional, Hanson, Jeff, additional, Splinter, Kristen, additional, Kinsela, Michael, additional, Lowe, Ryan, additional, Greenslade, Diana, additional, Zieger, Stefan, additional, and Taylor, Andy, additional

Published
2023
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15. Towards Improved Operational Wave Modelling at the Bureau of Meteorology.

Author

Zieger, Stefan and Peach, Leo

Subjects
METEOROLOGY, CONSTRUCTION materials, CONSTRUCTION projects, COASTAL zone management, CONTRACTORS
Abstract

The Bureau of Meteorology produces deterministic and ensemble forecasts for numerical weather prediction (NWP). The Bureau's operational wave forecast is currently limited to a global deterministic model (AUSWAVEG3). The current system has multi-resolution grid with a spatial resolution of 6 kilometres around Australia. It is therefore not able to accurately represent the transformation of deep-water waves to near shore and can exclude sub grid scale features such as islands or reefs. Over the past year a few smaller pilot projects highlighted the capability of variable resolution modelling around Australian coasts. The Bureau is trialling a new national coastal wave forecast system (AUSWAVE-NAT). AUSWAVE-NAT is nested within the Bureau's operational global wave model and currently produces research forecasts two times per day in near-real time. The wave model is driven by the Bureau's operational NWP model (ACCESS-G3) and incorporates ocean currents (OceanMAPS4.0i), with a spatial resolution of around 10 kilometres. The wave mesh incorporates a range of high-resolution bathymetric data, including Lidar bathymetry, and in particular high-resolution bathymetry for the Great Barrier Reef. As the approach uses an unstructured mesh, the size increases from about 10 kilometres (open ocean) to around 250 to 500 metres at the coast. The wave model is expected to extend the Bureau's capability to provide more accurate nearshore wave forecasts. This presentation will give an overview of the variable resolution national coastal wave forecast system and presents initial results, verification, and an overview of some use cases. [ABSTRACT FROM AUTHOR]

Published
2023

17. Global Wave Hindcasts Using the Observation‐Based Source Terms: Description and Validation

Author

Liu, Qingxiang, primary, Babanin, Alexander V., additional, Rogers, W. Erick, additional, Zieger, Stefan, additional, Young, Ian R., additional, Bidlot, Jean‐Raymond, additional, Durrant, Tom, additional, Ewans, Kevin, additional, Guan, Changlong, additional, Kirezci, Cagil, additional, Lemos, Gil, additional, MacHutchon, Keith, additional, Moon, Il‐Ju, additional, Rapizo, Henrique, additional, Ribal, Agustinus, additional, Semedo, Alvaro, additional, and Wang, Juanjuan, additional

Published
2021
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23. Global wave hindcast with Australian and Pacific Island Focus: From past to present.

Author

Smith, Grant A., Hemer, Mark, Greenslade, Diana, Trenham, Claire, Zieger, Stefan, and Durrant, Tom

Subjects
ISLANDS, ENGINEERING design, DOWNSCALING (Climatology), CLIMATOLOGY
Abstract

Wind‐wave hindcast data have many applications including climatology assessments for renewable energy projects, maritime engineering design, event‐based impact assessments, generating boundary conditions for further downscaling, amongst others. Here, we present a global wave hindcast with nested high‐resolution grids for the Exclusive Economic Zones of Australia and south west Pacific Island Countries, that is extended in time monthly. The model employs strategic methods to incorporate the effects of subgrid sized features such as small islands and islets. Various bulk wave parameters are available hourly from January 1979 to present, along with the full wave spectra at a set of 3,683 predetermined points distributed globally. [ABSTRACT FROM AUTHOR]

Published
2021
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26. Comparison and validation of physical wave parameterizations in spectral wave models

Author

Stopa, Justin, Ardhuin, Fabrice, Babanin, Alexander, Zieger, Stefan, Stopa, Justin, Ardhuin, Fabrice, Babanin, Alexander, and Zieger, Stefan

Abstract

Recent developments in the physical parameterizations available in spectral wave models have already been validated, but there is little information on their relative performance especially with focus on the higher order spectral moments and wave partitions. This study concentrates on documenting their strengths and limitations using satellite measurements, buoy spectra, and a comparison between the different models. It is confirmed that all models perform well in terms of significant wave heights; however higher-order moments have larger errors. The partition wave quantities perform well in terms of direction and frequency but the magnitude and directional spread typically have larger discrepancies. The high-frequency tail is examined through the mean square slope using satellites and buoys. From this analysis it is clear that some models behave better than the others, suggesting their parameterizations match the physical processes reasonably well. However none of the models are entirely satisfactory, pointing to poorly constrained parameterizations or missing physical processes. The major space-time differences between the models are related to the swell field stressing the importance of describing its evolution. An example swell field confirms the wave heights can be notably different between model configurations while the directional distributions remain similar. It is clear that all models have difficulty in describing the directional spread. Therefore, knowledge of the source term directional distributions is paramount in improving the wave model physics in the future.

Published
2016
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29. New Wave-Ice Interaction Physics in WAVEWATCH III

Author

NAVAL RESEARCH LAB STENNIS DETACHMENT STENNIS SPACE CENTER MS OCEANOGRAPHY DIV, Rogers, W E, Zieger, Stefan, NAVAL RESEARCH LAB STENNIS DETACHMENT STENNIS SPACE CENTER MS OCEANOGRAPHY DIV, Rogers, W E, and Zieger, Stefan

Abstract

The third generation model for wind-generated surface gravity waves WAVEWATCH III is modified to represent the effect of ice on waves as a source function. This replaces the existing approach of representing ice via fractional blocking (per grid cell) of wave propagation using ice concentration. We have implemented three alternative formulations of varying complexity. The first dissipative source function is a simplistic model where dissipation rate is specified directly. The second dissipative source function, based on work by A. Liu and others, assumes that dissipation is primarily caused by turbulence at the interface between water and a locally continuous ice layer. The third dissipative source function, based on work by H. Shen and others, treats the ice as a locally continuous visco-elastic layer (i.e. a two-layer model). In all cases, the ice characteristics may be specified as non-homogeneous and nonstationary fields. In the latter two source functions, the dissipation rate is non-uniform in frequency space, which is a highly intuitive and documented feature of wave-ice interaction: shorter waves are damped rapidly within the Marginal Ice Zone (MIZ), while the longest waves can penetrate several kilometers (at least) into the ice pack. These source functions are applied in preliminary hindcasts for August 2012 in the Beaufort and Chukchi Seas., Prepared in collaboration with Swinburne University, Melbourne, Australia. For presentation at the IAHR International Symposium on Ice (22nd), Singapore, 11-15 August 2014. The original document contains color images.

Published
2014

31. A framework for national-scale coastal storm hazards early warning.

Author

Turner, Ian L., Leaman, Christopher K., Harley, Mitchell D., Thran, Mandi C., David, Daniel R., Splinter, Kristen D., Matheen, Nashwan, Hansen, Jeff E., Cuttler, Michael V.W., Greenslade, Diana J.M., Zieger, Stefan, and Lowe, Ryan J.

Subjects
*BEACH erosion, *STORMS, *STORM surges, *EXTREME weather, *FLOOD warning systems, *WEATHER forecasting, *HAZARDS, *WEB portals
Abstract

National weather forecasting agencies routinely issue a range of hazard warnings. But to our knowledge, along sandy coastlines where storm waves and storm surge can result in widespread but location-specific beach erosion and beachfront flooding, no national-scale early warning service for these hazards is presently operational. This paper outlines the scientific basis and implementation of a new framework for large area coastal storm hazards forecasting, currently being tested along the southwest (Indian Ocean) and southeast (Pacific Ocean) coasts of Australia. The system provides 7-day rolling predictions of localized beach erosion and/or coastal flooding linked to forecasted extreme weather events. Coastal setting influences the nature and occurrence of these hazards, with sandy beaches along wave-dominated coasts more prone to erosion and at surge-dominated coasts to flooding. An existing nearshore water-level forecasting system and a new inshore wave modeling capability are used to forecast beach erosion and coastal flooding at every 100 m along the shore. At the regional scale O(100–1 000 km of coastline), a threshold-based decision tree model categorises the predicted extent, location, and severity of erosion and flooding. At a more local scale O(100–1 000 m), physics-based modeling using XBeach focuses on vulnerable or high-value locations, providing specific storm hazard indicators tailored to local needs. This two-tier approach is feasible for national implementation due to the reduced computational effort, limiting intensive modeling to pre-identified critical locations. Delft-FEWS manages the data and modeling workflow, ensuring scalability and compatibility with existing forecast infrastructure. Initial evaluations of the system are promising, with a detailed 2-year evaluation in progress. Future enhancements could include the use of satellite imagery for real-time beach width and dune topography assimilation and exploring alternative modeling approaches to further improve forecast accuracy. • A framework for coastal storm hazards early warning over very large areas is developed. • The severity of hazards is predicted every 100 m alongshore by parametric modeling. • Site-specific storm hazard indicators at vulnerable sites are predicted by XBeach. • 7-day rolling forecasts of storm hazards are communicated via a web portal. [ABSTRACT FROM AUTHOR]

Published
2024
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