An exceptionally high wave at the CNR-ISMAR oceanographic tower in the Northern Adriatic Sea

On December 15, 2009, a very high wave crest was recorded by a local camera at the CNR-ISMAR oceanographic tower, 15km offshore Venice in the Northern Adriatic Sea (Italy). The height of the estimated crest elevation appears well beyond the value (1,25.H-s) commonly used to identify a wave as freak. We document the wave event with a full description of the corresponding met-ocean conditions and related measurements, of which we provide a critical analysis

The 2015 exceptional swell in the Southern Pacific: Generation, advection, forecast and implied extremes

A very severe storm in the Antarctic belt is analysed that sent a very large swell throughout the South-Pacific Ocean. The reasons for the storm were a deep depression passing over an anomalous warm sea area, with consequent increased intensity, more active wind input, gustiness, with also dynamical generation. Wind and wave model results are verified with scatterometer and altimeter data. We follow the swell evolution during the five days required to reach the Galapagos Islands and a buoy off the Peruvian coast. The first forerunners peaked at 0.032 Hz at these locations, well represented in the model thanks to a purposely extended frequency range used in the WAM model. A nonlinear combined analysis is carried out to estimate the overall maximum single wave heights that may have impinged on the Galapagos coasts. Single wave heights up to 6 m have been estimated. Once generated, the swell conditions at Galapagos and the buoy are perfectly anticipated. Including generation, useful forecasts extend till at least eight days before the event. The lack of any local communication is discussed. An analysis using ERA5 winds, but a respectively higher resolution long-term wave hindcast, shows that a similar, actually stronger, event happened in 2006. A simple, but sound method, based on physical principles and elementary geometry, is proposed to estimate, firsthand and after any time, the maximum height of a once generated swell. The results for the 2015 storm are correct within 5% of the model values

European Radiometry Buoy and Infrastructure (EURYBIA): A Contribution to the Design of the European Copernicus Infrastructure for Ocean Colour System Vicarious Calibration

In the context of the Copernicus Program, EUMETSAT prioritizes the creation of an ocean color infrastructure for system vicarious calibration (OC-SVC). This work aims to reply to this need by proposing the European Radiometry Buoy and Infrastructure (EURYBIA). EURYBIA is designed as an autonomous European infrastructure operating within the Marine Optical Network (MarONet) established by University of Miami (Miami, FL, USA) based on the Marine Optical Buoy (MOBY) experience and NASA support. MarONet addresses SVC requirements in different sites, consistently and in a traceable way. The selected EURYBIA installation is close to the Lampedusa Island in the central Mediterranean Sea. This area is widely studied and hosts an Atmospheric and Oceanographic Observatory for long-term climate monitoring. The EURYBIA field segment comprises off-shore and on-shore infrastructures to manage the observation system and perform routine sensors calibrations. The ground segment includes the telemetry center for data communication and the processing center to compute data products and uncertainty budgets. The study shows that the overall uncertainty of EURYBIA SVC gains computed for the Sentinel-3 OLCI mission under EUMETSAT protocols is of about 0.05% in the blue-green wavelengths after a decade of measurements, similar to that of the reference site in Hawaii and in compliance with requirements for climate studies

European radiometry buoy and infrastructure (EURYBIA): A contribution to the design of the European copernicus infrastructure for ocean colour system vicarious calibration

In the context of the Copernicus Program, EUMETSAT prioritizes the creation of an ocean color infrastructure for system vicarious calibration (OC-SVC). This work aims to reply to this need by proposing the European Radiometry Buoy and Infrastructure (EURYBIA). EURYBIA is designed as an autonomous European infrastructure operating within the Marine Optical Network (MarONet) established by University of Miami (Miami, FL, USA) based on the Marine Optical Buoy (MOBY) experience and NASA support. MarONet addresses SVC requirements in different sites, consistently and in a traceable way. The selected EURYBIA installation is close to the Lampedusa Island in the central Mediterranean Sea. This area is widely studied and hosts an Atmospheric and Oceanographic Observatory for long-term climate monitoring. The EURYBIA field segment comprises off-shore and on-shore infrastructures to manage the observation system and perform routine sensors calibrations. The ground segment includes the telemetry center for data communication and the processing center to compute data products and uncertainty budgets. The study shows that the overall uncertainty of EURYBIA SVC gains computed for the Sentinel-3 OLCI mission under EUMETSAT protocols is of about 0.05% in the blue-green wavelengths after a decade of measurements, similar to that of the reference site in Hawaii and in compliance with requirements for climate studies

The mediterranean sea we want

open58siThis paper presents major gaps and challenges for implementing the UN Decade of Ocean Science for Sustainable Development (2021-2030) in the Mediterranean region. The authors make recommendations on the scientific knowledge needs and co-design actions identified during two consultations, part of the Decade preparatory-phase, framing them in the Mediterranean Sea’s unique environmental and socio-economic perspectives. According to the ‘Mediterranean State of the Environment and Development Report 2020’ by the United Nations Environment Programme Mediterranean Action Plan and despite notable progress, the Mediterranean region is not on track to achieve and fully implement the Sustainable Development Goals of Agenda 2030. Key factors are the cumulative effect of multiple human-induced pressures that threaten the ecosystem resources and services in the global change scenario. The basin, identified as a climate change vulnerability hotspot, is exposed to pollution and rising impacts of climate change. This affects mainly the coastal zones, at increasing risk of extreme events and their negative effects of unsustainable management of key economic assets. Transitioning to a sustainable blue economy is the key for the marine environment’s health and the nourishment of future generations. This challenging context, offering the opportunity of enhancing the knowledge to define science-based measures as well as narrowing the gaps between the Northen and Southern shores, calls for a joint (re)action. The paper reviews the state of the art of Mediterranean Sea science knowledge, sets of trends, capacity development needs, specific challenges, and recommendations for each Decade’s societal outcome. In the conclusions, the proposal for a Mediterranean regional programme in the framework of the Ocean Decade is addressed. The core objective relies on integrating and improving the existing ocean-knowledge, Ocean Literacy, and ocean observing capacities building on international cooperation to reach the “Mediterranean Sea that we want”.openCappelletto M.; Santoleri R.; Evangelista L.; Galgani F.; Garces E.; Giorgetti A.; Fava F.; Herut B.; Hilmi K.; Kholeif S.; Lorito S.; Sammari C.; Lianos M.C.; Celussi M.; D'alelio D.; Francocci F.; Giorgi G.; Canu D.M.; Organelli E.; Pomaro A.; Sannino G.; Segou M.; Simoncelli S.; Babeyko A.; Barbanti A.; Chang-Seng D.; Cardin V.; Casotti R.; Drago A.; Asmi S.E.; Eparkhina D.; Fichaut M.; Hema T.; Procaccini G.; Santoro F.; Scoullos M.; Solidoro C.; Trincardi F.; Tunesi L.; Umgiesser G.; Zingone A.; Ballerini T.; Chaffai A.; Coppini G.; Gruber S.; Knezevic J.; Leone G.; Penca J.; Pinardi N.; Petihakis G.; Rio M.-H.; Said M.; Siokouros Z.; Srour A.; Snoussi M.; Tintore J.; Vassilopoulou V.; Zavatarelli M.Cappelletto M.; Santoleri R.; Evangelista L.; Galgani F.; Garces E.; Giorgetti A.; Fava F.; Herut B.; Hilmi K.; Kholeif S.; Lorito S.; Sammari C.; Lianos M.C.; Celussi M.; D'alelio D.; Francocci F.; Giorgi G.; Canu D.M.; Organelli E.; Pomaro A.; Sannino G.; Segou M.; Simoncelli S.; Babeyko A.; Barbanti A.; Chang-Seng D.; Cardin V.; Casotti R.; Drago A.; Asmi S.E.; Eparkhina D.; Fichaut M.; Hema T.; Procaccini G.; Santoro F.; Scoullos M.; Solidoro C.; Trincardi F.; Tunesi L.; Umgiesser G.; Zingone A.; Ballerini T.; Chaffai A.; Coppini G.; Gruber S.; Knezevic J.; Leone G.; Penca J.; Pinardi N.; Petihakis G.; Rio M.-H.; Said M.; Siokouros Z.; Srour A.; Snoussi M.; Tintore J.; Vassilopoulou V.; Zavatarelli M

Accuracy of global and high resolution models in stormy conditions

We analyse the performance of two top level meteorological models and their associated analyses versus the corresponding results obtained with high resolution nesting both for wind and for the derived wave field using the same advanced wave model. The comparison is also done versus both locally (buoys) and large scale (altimeter and scatterometer) measured data. It turns out that nested high resolution modelling does in general lead to a lower bias, but at the expense of larger root mean square errors and scatter indexes when compared with measured data. The reasons for this are discussed and a possible solution is indicated. Copyright © 2013 by the International Society of Offshore and Polar Engineers (ISOPE)

39 years of directional wave recorded data at the Acqua Alta oceanographic tower

The dataset consists of a 39-year long directional wave time series recorded since 1979 at the CNR-ISMAR "Acqua Alta" oceanographic research tower (AAOT), located in the Northern Adriatic Sea. The extent of the time series allows to describe the wave climate in the North Adriatic region and to identify trends and links with large scale climate patterns from a single and permanent observational source. The northern part of the Adriatic Sea is characterized by two main wind and correspondingly wave regimes, strongly forced by the regional orography. The high sensitivity of this particular area to even small variations of large scale meteorological patterns allows to explore possible links of the local wave, hence wind, activity with large-scale north hemisphere circulation or weather regimes. Different wave gauges have been used since the start of the measurements, progressively upgraded and repositioned during maintenance operations. The recorded wave data have been thoroughly verified and corrected where necessary

39 years of directional wave recorded data at the Acqua Alta oceanographic tower

The dataset consists of 39 years of directional wave time series recorded since 1979 at the CNR-ISMAR “Acqua Alta” oceanographic research tower, located in the Northern Adriatic Sea. The extent of the time series allows us to describe the wave climate in the North Adriatic region and to identify trends and links with large scale climate patterns obtained from a single and permanent observational source. The northern part of the Adriatic Sea is characterized by two main wind and correspondingly wave regimes, strongly forced by the regional orography. The high sensitivity of this particular area to even small variations of large scale meteorological patterns allows to explore possible links of the local wave, hence wind, activity with large-scale north hemisphere circulation or weather regimes. Different wave gauges have been used since the start of the measurements, progressively upgraded and repositioned during maintenance operations. The recorded wave data have been thoroughly verified and corrected where necessary

Synergic use of altimeter and model sea level data in inner and coastal seas

We analyse high rate (20 Hz) altimeter derived sea level information, both from Synthetic Aperture Radar (SAR) altimetry missions and Low Resolution Mode missions, in an inner sea and coastal environment. They are compared versus measured and high resolution model data. After a compact description of the relevant physical processes affecting the local sea level values, we focus on three specific passes on the Adriatic Sea, East of Italy. Our main finding is that altimeters and models provide both valuable, partially overlapping, but complementary, information to be exploited in parallel with a double purpose: to progressively approach the truth and to ensure the parallel improvement of both sources. From altimeter data there is a very strong suggestion that the spatial, and implicitly temporal, variability of the fields is much higher than shown by models. The reasons are discussed