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2. Publisher Correction: A global overview of marine heatwaves in a changing climate

Author

Capotondi, Antonietta, Rodrigues, Regina R., Sen Gupta, Alex, Benthuysen, Jessica A., Deser, Clara, Frölicher, Thomas L., Lovenduski, Nicole S., Amaya, Dillon J., Le Grix, Natacha, Xu, Tongtong, Hermes, Juliet, Holbrook, Neil J., Martinez-Villalobos, Cristian, Masina, Simona, Roxy, Mathew Koll, Schaeffer, Amandine, Schlegel, Robert W., Smith, Kathryn E., and Wang, Chunzai

Published
2024
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4. A global overview of marine heatwaves in a changing climate

Author

Capotondi, Antonietta, Rodrigues, Regina R., Sen Gupta, Alex, Benthuysen, Jessica A., Deser, Clara, Frölicher, Thomas L., Lovenduski, Nicole S., Amaya, Dillon J., Le Grix, Natacha, Xu, Tongtong, Hermes, Juliet, Holbrook, Neil J., Martinez-Villalobos, Cristian, Masina, Simona, Roxy, Mathew Koll, Schaeffer, Amandine, Schlegel, Robert W., Smith, Kathryn E., and Wang, Chunzai

Published
2024
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11. Mid-Pliocene El Niño/Southern Oscillation suppressed by Pacific intertropical convergence zone shift

Author

Pontes, Gabriel M., Taschetto, Andréa S., Sen Gupta, Alex, Santoso, Agus, Wainer, Ilana, Haywood, Alan M., Chan, Wing-Le, Abe-Ouchi, Ayako, Stepanek, Christian, Lohmann, Gerrit, Hunter, Stephen J., Tindall, Julia C., Chandler, Mark A., Sohl, Linda E., Peltier, W. Richard, Chandan, Deepak, Kamae, Youichi, Nisancioglu, Kerim H., Zhang, Zhongshi, Contoux, Camille, Tan, Ning, Zhang, Qiong, Otto-Bliesner, Bette L., Brady, Esther C., Feng, Ran, von der Heydt, Anna S., Baatsen, Michiel L. J., and Oldeman, Arthur M.

Published
2022
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14. Optimising the design and analysis of capture-mark-recapture experiments using individual-based models.

Author

Scutt Phillips, Joe, Lehodey, Jules, Senina, Inna, Barker, Richard, Peatman, Tom, Schofield, Matthew, Sen Gupta, Alex, van Sebille, Erik, and Nicol, Simon

Subjects
PARAMETER estimation, SKIPJACK tuna, ECOLOGICAL heterogeneity, WILDLIFE conservation, ANIMAL tagging
Abstract

Capture-mark-recapture methods (CMR) are a commonly used tool in species conservation and management for the estimation of demographic parameters in a population. However, biases in these estimates can occur due to the heterogeneity in processes influencing recapture data or the experimental design. We outline an approach to quantify and identify ways to reduce this bias through both experimental design and data analysis, using individual based modelling (IBMs). By using an IBM that includes key sources of heterogeneity that are believed to exist in the system, the release and recapture of marked individuals can be simulated under differing experimental, behavioural or landscape scenarios. Using this IBM as a data-generator, we compare a simulated population of individuals with a subset of that population that represent those marked and recaptured in a CMR experiment. Parameter estimates from the data generated by the marked subset are then compared to 'true', realised parameters from the wider, unmarked population. We demonstrate this with an application of 'simulated tagging' of Pacific skipjack tuna (Katsuwonus pelamis), using scenarios of different release locations of marked individuals, alternative band-recovery models, and differing assumptions that define the spatial extent of the unmarked population. We quantify the error in the estimated survival and fishing mortality parameters and examine how these can be reduced by following differing release and analysis strategies. We show that spatiotemporal heterogeneity of individual dispersion and recovery effort (i.e. fishing pressure) led to severe bias in recapture probability estimates, up to 361%, regardless of experimental design. However, when the baseline of the unmarked population of which marked animals were assumed to be representative was defined by spatial coverage of recaptures, rather than a fixed, spatial management area, bias was reduced to 25%. Our results show that the use of IBM frameworks exploring alternative hypotheses, either in the design of or post-hoc analyses of CMR experiments, support maximising the information that can be derived and quantify the degree of potential bias due to analysis model mis-specification. Furthermore, these methods can benefit other sampling and monitoring programmes in systems with high levels of spatial or ecological heterogeneity. [ABSTRACT FROM AUTHOR]

Published
2024
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15. Simulating drifting fish aggregating device trajectories to identify potential interactions with endangered sea turtles.

Author

Escalle, Lauriane, Scutt Phillips, J., Lopez, J., Lynch, J. M., Murua, H., Royer, S. J., Swimmer, Y., Murua, J., Sen Gupta, Alex, Restrepo, V., and Moreno, G.

Subjects
SEA turtles, LEATHERBACK turtle, HAWKSBILL turtle, MARINE debris, MARINE pollution
Abstract

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2024
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16. Global Predictability of Marine Heatwave Induced Rapid Intensification of Tropical Cyclones.

Author

Radfar, Soheil, Foroumandi, Ehsan, Moftakhari, Hamed, Moradkhani, Hamid, Foltz, Gregory R., and Sen Gupta, Alex

Subjects
MACHINE learning, MARINE heatwaves, OCEAN temperature, GLOBAL warming, EMERGENCY management, TROPICAL cyclones
Abstract

Prediction of the rapid intensification (RI) of tropical cyclones (TCs) is crucial for improving disaster preparedness against storm hazards. These events can cause extensive damage to coastal areas if occurring close to landfall. Available models struggle to provide accurate RI estimates due to the complexity of underlying physical mechanisms. This study provides new insights into the prediction of a subset of rapidly intensifying TCs influenced by prolonged ocean warming events known as marine heatwaves (MHWs). MHWs could provide sufficient energy to supercharge TCs. Preconditioning by MHW led to RI of recent destructive TCs, Otis (2023), Doksuri (2023), and Ian (2022), with economic losses exceeding $150 billion. Here, we analyze the TC best track and sea surface temperature data from 1981 to 2023 to identify hotspot regions for compound events, where MHWs and RI of tropical cyclones occur concurrently or in succession. Building upon this, we propose an ensemble machine learning model for RI forecasting based on storm and MHW characteristics. This approach is particularly valuable as RI forecast errors are typically largest in favorable environments, such as those created by MHWs. Our study offers insight into predicting MHW TCs, which have been shown to be stronger TCs with potentially higher destructive power. Here, we show that using MHW predictors instead of the conventional method of using sea surface temperature reduces the false alarm rate by 30%. Overall, our findings contribute to coastal hazard risk awareness amidst unprecedented climate warming causing more frequent MHWs. Plain Language Summary: Tropical cyclones (TCs) that rapidly intensify pose a significant threat to coastal areas. Current prediction models struggle to accurately forecast these events due to the complex nature of underlying physical processes. This study focuses on improving predictions for a specific type of rapidly intensifying TCs influenced by prolonged ocean warming events known as marine heatwaves. By developing an ensemble machine learning model that considers storm and marine heatwaves characteristics, we provide a new tool for detecting rapid intensification events that are particularly challenging to forecast in favorable environments created by MHWs. These events tend to produce stronger TCs. The developed model demonstrated higher accuracy in detecting rapid intensification while reducing false alarms. This research enhances coastal hazard preparedness in the face of rising ocean temperatures. Key Points: Global hotspots for marine heatwave‐induced rapid intensifications identified, accounting for over $360 billion in losses only in 2021–2023An ensemble machine learning model is developed to predict this destructive subset of RI eventsWe quantify enhanced predictive skill achieved by using marine heatwave intensity metrics as predictors compared to sea surface temperature [ABSTRACT FROM AUTHOR]

Published
2024
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27. Drivers and impacts of the most extreme marine heatwave events

Author

Sen Gupta, Alex, Thomsen, Mads, Benthuysen, Jessica A., Hobday, Alistair J., Oliver, Eric, Alexander, Lisa V., Burrows, Michael T., Donat, Markus G., Feng, Ming, Holbrook, Neil J., Perkins-Kirkpatrick, Sarah, Moore, Pippa J., Rodrigues, Regina R., Scannell, Hillary A., Taschetto, Andréa S., Ummenhofer, Caroline C., Wernberg, Thomas, and Smale, Dan A.

Published
2020
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30. A hierarchical approach to defining marine heatwaves

Author

Hobday, Alistair J., Alexander, Lisa V., Perkins, Sarah E., Smale, Dan A., Straub, Sandra C., Oliver, Eric C.J., Benthuysen, Jessica A., Burrows, Michael T., Donat, Markus G., Feng, Ming, Holbrook, Neil J., Moore, Pippa J., Scannell, Hillary A., Sen Gupta, Alex, and Wernberg, Thomas

Published
2016
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34. Marine biodiversity exposed to prolonged and intense subsurface heatwaves

Author

Fundação para a Ciência e a Tecnologia (Portugal), Australian Research Council, Fondation BNP Paribas, Fragkopoulou, Eliza, Sen Gupta, Alex, Costello, Mark John, Wernberg, Thomas, Araújo, Miguel B., Serrão, Ester A., De Clerck, Olivier, Assis, Jorge, Fundação para a Ciência e a Tecnologia (Portugal), Australian Research Council, Fondation BNP Paribas, Fragkopoulou, Eliza, Sen Gupta, Alex, Costello, Mark John, Wernberg, Thomas, Araújo, Miguel B., Serrão, Ester A., De Clerck, Olivier, and Assis, Jorge

Abstract

Marine heatwaves (MHWs) are becoming increasingly common, with devastating ecosystem impacts. However, MHW understanding has almost exclusively relied on sea surface temperature with limited knowledge about their subsurface characteristics. Here we estimate global MHWs from the surface to 2,000 m depth, covering the period 1993–2019, and explore biodiversity exposure to their effects. We find that MHWs are typically more intense in the subsurface at 50–200 m and their duration increases up to twofold with depth, although with large spatial variability linked to different oceanographic conditions. Cumulative intensity (a thermal stress proxy) was highest in the upper 250 m, exposing subsurface biodiversity to MHW effects. This can be particularly concerning for up to 22% of the ocean, where high cumulative intensity overlapped the warm range edge of species distributions, thus being more sensitive to thermal stress. Subsurface MHWs can hence drive biodiversity patterns, with consequent effects on ecological interactions and ecosystem processes.

Published
2023

35. Is Australia weird? A cross-continental comparison of biological, geological and climatological features

Author

Flores-Moreno, Habacuc, primary, Dalrymple, Rhiannon L., additional, Cornwell, Will K., additional, Popovic, Gordana, additional, Nakagawa, Shinichi, additional, Atkinson, Joe, additional, Cooke, Julia, additional, Laffan, Shawn W., additional, Bonser, Stephen P., additional, Schwanz, Lisa E., additional, Crean, Angela J., additional, Eldridge, David J., additional, Garratt, Michael, additional, Brooks, Robert C., additional, Vergés, Adriana, additional, Poore, Alistair G. B., additional, Cohen, David R., additional, Clark, Graeme F., additional, Sen Gupta, Alex, additional, Reich, Peter B., additional, Cornelissen, J. Hans C., additional, Craine, Joseph M., additional, Hemmings, Frank A., additional, Kattge, Jens, additional, Niinemets, Ülo, additional, Peñuelas, Josep, additional, and Moles, Angela T., additional

Published
2023
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39. Seasonal stratification and complex local dynamics control the vertical structure of marine heatwaves in coastal waters

Author

Schaeffer, Amandine, Sen Gupta, Alex, and Roughan, Moninya

Abstract

Marine heatwaves (MHWs) are extreme ocean events that may have severe and long-lasting impacts on marine life. The level of ecosystem stress and whether organisms are displaced or perish during MHWs depends on species’ thermal thresholds and ability to adapt, but also depends on the characteristics of the events, including their depth structure. However, due to a paucity of in situ measurements below the surface, the vertical structure of MHWs is poorly understood. Here we use one of the longest (27 years) records of daily sub-surface ocean temperature anywhere, spanning the water column in 65 m of water off Sydney, Australia, to explore the sub-surface coherence of MHWs and its controls.We show that MHW events often extend over the whole water column in weakly stratified months and are the longest, driven by the intrusion onto the shelf of warm large-scale currents, while during periods of strong stratification, shallow and deep MHW events are typically uncoupled.Shallow events are mostly driven by anomalous air-sea fluxes, while downwelling favourable winds trigger sub-surface MHWs. The sub-surface events tend to be the most intense, but also the shortest.These results highlight that, when considering coastal areas where maximum biological damage is reported, sea surface temperature extremes such as MHWs, are not representative of the water column below the shallow mixed layer during stratified months., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Published
2023

40. Exploring marine heatwave predictability

Author

Holbrook, Neil, Benthuysen, Jessica, Kajtar, Jules, Sen Gupta, Alex, Spillman, Claire, Zhang, Xuebin, Gregory, Catherine, Li, Zeya, Reilly, John, Wang, Yuxin, Zhang, Shujing, and Marshall, Andrew

Abstract

Marine heatwaves (MHWs) are prolonged extreme oceanic warm water events, that can cause substantial and sometimes devastating impacts on marine ecosystems. Our knowledge of regional and remote drivers, teleconnections, and local-scale processes underpinning large-scale and iconic MHWs has improved significantly over the past decade because of focused research efforts around the world. Dynamical knowledge of MHW drivers, including those from remote sources such as modes of climate variability and their teleconnections, coupled with local MHW amplification or decay processes, is critical to the process-based understanding of MHW predictability. However, the key development needed for effective adaptation and mitigation efforts by marine conservation and fisheries managers is better MHW prediction skill. MHW predictability depends on multiple factors including how we define MHWs, the regions in which they occur – e.g., coastal versus offshore, western boundary versus eastern boundary regions –, the spatial and temporal scales of the events, atmospheric heat flux versus ocean advection-driven events, and driver persistence. This presentation will explore MHW predictability on various timescales, focusing on the physical processes that offer a prediction. Some significant MHW events around Australia will be central to this discussion., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Published
2023

42. Biological Impacts of Marine Heatwaves

Author

Smith, Kathryn E., primary, Burrows, Michael T., additional, Hobday, Alistair J., additional, King, Nathan G., additional, Moore, Pippa J., additional, Sen Gupta, Alex, additional, Thomsen, Mads S., additional, Wernberg, Thomas, additional, and Smale, Dan A., additional

Published
2023
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45. From severe droughts in South America to marine heatwaves in the South Atlantic

Author

Rodrigues, Regina, Taschetto, Andrea ; https://orcid.org/0000-0001-6020-1603, Sen Gupta, Alex ; https://orcid.org/0000-0001-5226-871X, Foltz, Gregory, Rodrigues, Regina, Taschetto, Andrea ; https://orcid.org/0000-0001-6020-1603, Sen Gupta, Alex ; https://orcid.org/0000-0001-5226-871X, and Foltz, Gregory

Abstract

In 2013/14 eastern South America experienced one of its worst droughts, leading to water shortages in Sao Paulo, the world's fourth most populated city. This event was also responsible for a dengue fever outbreak that tripled the usual number of fatalities and reduced Brazilian coffee production leading to a global shortages and worldwide price increases. The drought was associated with an anomalous anticyclonic circulation off southeast South America that prevented synoptic systems reaching the region while inhibiting the development of the South Atlantic Convergence Zone and its associated rainfall. A concomitant and unprecedented marine heatwave also developed in the southwest Atlantic. Here we show from observations that such droughts and adjacent marine heatwaves have a common remote cause. Atmospheric blocking triggered by tropical convection in the Indian and Pacific oceans can cause persistent anticyclonic circulation that not only leads to severe drought but also generates marine heatwaves in the adjacent ocean. We show that increased shortwave radiation due to reduced cloud cover and reduced ocean heat loss from weaker winds are the main contributors to the establishment of marine heatwaves in the region. The proposed mechanism, which involves droughts, extreme air temperature over land and atmospheric blocking explains approximately 60% of the marine heatwave events in the western South Atlantic. We also identified an increase in frequency, duration, intensity and extension of marine heatwave events over the satellite period 1982–2016. Moreover, surface primary production was reduced during these events with implications for regional fisheries.

Published
2022

46. Mid-Pliocene El Niño/Southern Oscillation suppressed by Pacific intertropical convergence zone shift

Author

Sub Physical Oceanography, Sub Dynamics Meteorology, Marine and Atmospheric Research, Pontes, Gabriel M., Taschetto, Andrea S., Sen Gupta, Alex, Santoso, Agus, Wainer, Ilana, Haywood, Alan M., Chan, Wing-Le, Abe-Ouchi, Ayako, Stepanek, Christian, Lohmann, Gerrit, Hunter, Stephen J., Tindall, Julia C., Chandler, Mark A., Sohl, Linda E., Peltier, W. Richard, Chandan, Deepak, Kamae, Youichi, Nisancioglu, Kerim H., Zhang, Zhongshi, Contoux, Camille, Tan, Ning, Zhang, Qiong, Otto-Bliesner, Bette L., Brady, Esther C., Feng, Ran, von der Heydt, Anna S., Baatsen, Michiel L. J., Oldeman, Arthur M., Sub Physical Oceanography, Sub Dynamics Meteorology, Marine and Atmospheric Research, Pontes, Gabriel M., Taschetto, Andrea S., Sen Gupta, Alex, Santoso, Agus, Wainer, Ilana, Haywood, Alan M., Chan, Wing-Le, Abe-Ouchi, Ayako, Stepanek, Christian, Lohmann, Gerrit, Hunter, Stephen J., Tindall, Julia C., Chandler, Mark A., Sohl, Linda E., Peltier, W. Richard, Chandan, Deepak, Kamae, Youichi, Nisancioglu, Kerim H., Zhang, Zhongshi, Contoux, Camille, Tan, Ning, Zhang, Qiong, Otto-Bliesner, Bette L., Brady, Esther C., Feng, Ran, von der Heydt, Anna S., Baatsen, Michiel L. J., and Oldeman, Arthur M.

Published
2022

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