Articles | Volume 18, issue 10
https://doi.org/10.5194/essd-18-7181-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/essd-18-7181-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Data description article
| 
30 Sep 2026
Data description article |
| 30 Sep 2026
| 30 Sep 2026
Marine Heat Waves and Cold Spells – Multiple Analysis/Definitions (MHW-MAD): A Multi-Definition Global Marine Heatwave Database from Satellite Sea Surface Temperature Data
Danish Meteorological Institute (DMI), Copenhagen, Denmark
Nishka Dasgupta
Danish Meteorological Institute (DMI), Copenhagen, Denmark
Ronan McAdam
CMCC Foundation – Euro-Mediterranean Centre on Climate Change, Bologna, Italy
Mark R. Payne
Danish Meteorological Institute (DMI), Copenhagen, Denmark
Roshin P. Raj
Nansen Environmental and Remote Sensing Center, and Bjerknes Centre for Climate Research, Bergen, Norway
Giulia Bonino
CMCC Foundation – Euro-Mediterranean Centre on Climate Change, Bologna, Italy
Sourav Chatterjee
National Centre for Polar and Ocean Research (NCPOR), Goa, India
Centre for Climate Change Research, Indian Institute of Tropical Meteorology (IITM), Ministry of Earth Sciences, Pune, India
Vincent Combes
Institut Mediterrani d'Estudis Avançats, IMEDEA (CSIC-UIB), Esporles, Spain
Dimitra Denaxa
Hellenic Centre for Marine Research (HCMR), Athens, Greece
Francesco De Rovere
CMCC Foundation – Euro-Mediterranean Centre on Climate Change, Bologna, Italy
Pia Englyst
Danish Meteorological Institute (DMI), Copenhagen, Denmark
Veera Haapaniemi
Finnish Meteorological Institute (FMI), Helsinki, Finland
Paul Hargous
Institut Mediterrani d'Estudis Avançats, IMEDEA (CSIC-UIB), Esporles, Spain
Jacob Høyer
Danish Meteorological Institute (DMI), Copenhagen, Denmark
K. Ajith Joseph
Nansen Environmental Research Centre India (NERCI), Kochi, India
Beatriz Lopes
+ATLANTIC CoLAB, Matosinhos, Portugal
Ana Oliveira
+ATLANTIC CoLAB, Matosinhos, Portugal
João Paixão
+ATLANTIC CoLAB, Matosinhos, Portugal
Fabiola Silva
+ATLANTIC CoLAB, Matosinhos, Portugal
Saradhy Surendran
Nansen Environmental Research Centre India (NERCI), Kochi, India
Kerala University of Fisheries and Ocean Studies (KUFOS), Kochi, India
Artemis Zegna-Rata
Laboratoire de Météorologie Dynamique (LMD), Paris, France
Steffen M. Olsen
Danish Meteorological Institute (DMI), Copenhagen, Denmark
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Bogi Hansen, Karin M. H. Larsen, Hjálmar Hátún, Steffen M. Olsen, Andrea M. U. Gierisch, Svein Østerhus, and Sólveig R. Ólafsdóttir
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Based on in situ observations combined with sea level anomaly (SLA) data from satellite altimetry, volume as well as heat (relative to 0 °C) transport of the Iceland–Faroe warm-water inflow towards the Arctic (IF inflow) increased from 1993 to 2021. The reprocessed SLA data released in December 2021 represent observed variations accurately. The IF inflow crosses the Iceland–Faroe Ridge in two branches, with retroflection in between. The associated coupling to overflow reduces predictability.
Leonardo Lima, Salvatore Causio, Mehmet Ilicak, Ronan McAdam, and Eric Jansen
State Planet Discuss., https://doi.org/10.5194/sp-2023-19, https://doi.org/10.5194/sp-2023-19, 2023
Revised manuscript not accepted
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Recent studies have revealed an increase in the ocean temperature and heat content in the Black Sea, where the research on marine heat waves (MHWs) is still incipient. Our study reveals long-lasting MHWs and interesting connections between surface and subsurface MHWs in the Black Sea. Our analysis is a starting point to create a monitoring system of MHWs for the Black Sea.
Giulia Bonino, Simona Masina, Giuliano Galimberti, and Matteo Moretti
Earth Syst. Sci. Data, 15, 1269–1285, https://doi.org/10.5194/essd-15-1269-2023, https://doi.org/10.5194/essd-15-1269-2023, 2023
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We present a unique observational dataset of marine heat wave (MHW) macroevents and their characteristics over southern Europe and western Asian (SEWA) basins in the SEWA-MHW dataset. This dataset is the first effort in the literature to archive extremely hot sea surface temperature macroevents. The advantages of the availability of SEWA-MHWs are avoiding the waste of computational resources to detect MHWs and building a consistent framework which would increase comparability among MHW studies.
Jiping Xie, Roshin P. Raj, Laurent Bertino, Justino Martínez, Carolina Gabarró, and Rafael Catany
Ocean Sci., 19, 269–287, https://doi.org/10.5194/os-19-269-2023, https://doi.org/10.5194/os-19-269-2023, 2023
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Sea ice melt, together with other freshwater sources, has effects on the Arctic environment. Sea surface salinity (SSS) plays a key role in representing water mixing. Recently the satellite SSS from SMOS was developed in the Arctic region. In this study, we first evaluate the impact of assimilating these satellite data in an Arctic reanalysis system. It shows that SSS errors are reduced by 10–50 % depending on areas, encouraging its use in a long-time reanalysis to monitor the Arctic water cycle.
Vidar S. Lien and Roshin P. Raj
State Planet Discuss., https://doi.org/10.5194/sp-2022-13, https://doi.org/10.5194/sp-2022-13, 2022
Preprint withdrawn
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Dense overflow water entering the North Atlantic from the Nordic Seas forms the northern limb of the Atlantic Meridional Overturning Circulation. The formation of dense water in the Nordic Seas is sensitive to the properties of the northward flowing Atlantic Water entering the Nordic Seas to the south. We find that the unprecedented freshwater anomaly in the North Atlantic recent years caused the dense water formed in the Barents Sea to have the lowest density in recorded history.
Charikleia L. G. Oikonomou, Dimitra Denaxa, and Gerasimos Korres
State Planet Discuss., https://doi.org/10.5194/sp-2022-16, https://doi.org/10.5194/sp-2022-16, 2022
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We explore the wave energy resource within the Mediterranean basin, along with the dominant wave regime. Results suggest that although the basin is not characterised by high energy potential, it could serve as a deployment zone for low-power devices due to low peak period variability and high site accessibility levels. Results suggest that further research is required to determine the dominant wave regime, as the high contribution of swell partitions hints the occurrence of mixed sea states.
Ioanna Karagali, Magnus Barfod Suhr, Ruth Mottram, Pia Nielsen-Englyst, Gorm Dybkjær, Darren Ghent, and Jacob L. Høyer
The Cryosphere, 16, 3703–3721, https://doi.org/10.5194/tc-16-3703-2022, https://doi.org/10.5194/tc-16-3703-2022, 2022
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Ice surface temperature (IST) products were used to develop the first multi-sensor, gap-free Level 4 (L4) IST product of the Greenland Ice Sheet (GIS) for 2012, when a significant melt event occurred. For the melt season, mean IST was −15 to −1 °C, and almost the entire GIS experienced at least 1 to 5 melt days. Inclusion of the L4 IST to a surface mass budget (SMB) model improved simulated surface temperatures during the key onset of the melt season, where biases are typically large.
Giulia Bonino, Doroteaciro Iovino, Laurent Brodeau, and Simona Masina
Geosci. Model Dev., 15, 6873–6889, https://doi.org/10.5194/gmd-15-6873-2022, https://doi.org/10.5194/gmd-15-6873-2022, 2022
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The sea surface temperature (SST) is highly influenced by the transfer of energy driven by turbulent air–sea fluxes (TASFs). In the NEMO ocean general circulation model, TASFs are computed by means of bulk formulas. Bulk formulas require the choice of a given bulk parameterization, which influences the magnitudes of the TASFs. Our results show that parameterization-related SST differences are primarily sensitive to the wind stress differences across parameterizations.
Martin Horwath, Benjamin D. Gutknecht, Anny Cazenave, Hindumathi Kulaiappan Palanisamy, Florence Marti, Ben Marzeion, Frank Paul, Raymond Le Bris, Anna E. Hogg, Inès Otosaka, Andrew Shepherd, Petra Döll, Denise Cáceres, Hannes Müller Schmied, Johnny A. Johannessen, Jan Even Øie Nilsen, Roshin P. Raj, René Forsberg, Louise Sandberg Sørensen, Valentina R. Barletta, Sebastian B. Simonsen, Per Knudsen, Ole Baltazar Andersen, Heidi Ranndal, Stine K. Rose, Christopher J. Merchant, Claire R. Macintosh, Karina von Schuckmann, Kristin Novotny, Andreas Groh, Marco Restano, and Jérôme Benveniste
Earth Syst. Sci. Data, 14, 411–447, https://doi.org/10.5194/essd-14-411-2022, https://doi.org/10.5194/essd-14-411-2022, 2022
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Global mean sea-level change observed from 1993 to 2016 (mean rate of 3.05 mm yr−1) matches the combined effect of changes in water density (thermal expansion) and ocean mass. Ocean-mass change has been assessed through the contributions from glaciers, ice sheets, and land water storage or directly from satellite data since 2003. Our budget assessments of linear trends and monthly anomalies utilise new datasets and uncertainty characterisations developed within ESA's Climate Change Initiative.
Justino Martínez, Carolina Gabarró, Antonio Turiel, Verónica González-Gambau, Marta Umbert, Nina Hoareau, Cristina González-Haro, Estrella Olmedo, Manuel Arias, Rafael Catany, Laurent Bertino, Roshin P. Raj, Jiping Xie, Roberto Sabia, and Diego Fernández
Earth Syst. Sci. Data, 14, 307–323, https://doi.org/10.5194/essd-14-307-2022, https://doi.org/10.5194/essd-14-307-2022, 2022
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Measuring salinity from space is challenging since the sensitivity of the brightness temperature to sea surface salinity is low, but the retrieval of SSS in cold waters is even more challenging. In 2019, the ESA launched a specific initiative called Arctic+Salinity to produce an enhanced Arctic SSS product with better quality and resolution than the available products. This paper presents the methodologies used to produce the new enhanced Arctic SMOS SSS product.
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Short summary
We present a global marine heatwave and cold spell dataset (1982–2024) based on satellite sea surface temperature. The dataset applies multiple definitions in parallel, varying baselines, thresholds, detrending, and event durations. It enables consistent comparisons of marine heatwave characterisation across methods and supports climate monitoring, and ecological impact studies.
We present a global marine heatwave and cold spell dataset (1982–2024) based on satellite sea...
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