• The Ecology and Oceanography of Harmful Algal Blooms: Multidisciplinary Approaches to Research and Management. Anton Bruum Memorial Lecture, presented 27 June 2005, UNESCO, Paris

      Anderson, Donald M (UNESCOParis, France, 2007)
      Virtually every coastal country in the world is affected by harmful algal blooms (HABs, commonly called “red tides”). This diverse array of phenomena includes blooms of toxic, microscopic algae that lead to illness and death in humans, fish, seabirds, marine mammals, and other oceanic life. There are also non-toxic HABs that cause damage to ecosystems, fisheries resources, and recreational facilities, often due to the sheer biomass of the accumulated algae. The term “HAB” also applies to non-toxic macroalgae (seaweeds), which can cause major ecological impacts such as the displacement of indigenous species, habitat alteration and oxygen depletion in bottom waters. The frequency, spatial extent, and economic impact of HABs have all expanded in recent decades, in parallel with, and sometimes a result of, the world’s increasing exploitation on the coastal zone for shelter, food, recreation, and commerce. HABs are complex oceanographic phenomena that require multidisciplinary study ranging from molecular and cell biology to large-scale field surveys, numerical modelling, and remote sensing from space. Multi-lateral international programmes and bilateral initiatives are bringing scientists together from different countries and disciplines in a concerted attack on this complex and multi-faceted issue. Our understanding of these phenomena is increasing dramatically, and with this understanding come technologies and management tools that can reduce HAB incidence and impact. More effective HAB management is sure to be one major outcome of the growing investment in the Global Ocean Observing System. HABs will always be with us, and in the next few decades at least, are likely to continue to expand in geographic extent and frequency. Nevertheless, scientifically based management should permit full exploitation of fisheries, recreational, and commercial resources, despite the recurrent and diverse threat that HABs pose. This series of lectures is dedicated to the memory of the noted Danish oceanographer and first chairman of the Commission, Dr Anton Frederick Bruun. The "Anton Bruun Memorial Lectures" were established in accordance with Resolution 19 of the Sixth Session of the IOC Assembly, in which the Commission proposed that important inter-session developments be summarized by speakers in the fields of solid earth studies, physical and chemical oceanography and meteorology, and marine biology.
    • 27 February 2010 Chile Earthquake and Tsunami Event: Post-Event Assessment of PTWS Performance.

      Aliaga, Bernardo; Yamamoto, Masahiro; Mosquera, Diana Patricia; Intergovernmental Oceanographic Commission (UNESCO-IOCParis, France, 2010)
      A series of severe earthquakes hit Central Chile on Saturday, 27th February 2010. The main shock off Concepcion at 06:34 UTC (3:34 AM local time) had a magnitude of 8.8 Mw. The Pacific Tsunami Warning Center PTWC in Hawaii, USA issued a regional warning at 06:46 UTC (12 minutes after the event). This was the first ocean wide test of a system that was put in place nearly 45 years ago by UNESCO’s Member States through its Intergovernmental Oceanographic Commission (IOC), after a 9.5 magnitude earthquake on 22 May 22 1960 off Chile triggered a wide ocean tsunami that caused 61 fatalities in Hawaii and 142 fatalities in Japan, several hours after the earthquake. As indicated above, 12 minutes after the 27th February 2010 earthquake the Pacific Ocean Tsunami Warning System (PTWS) went into action, with timely and adequate information produced and disseminated across the Pacific Ocean. There were no fatalities reported far from the epicenter, however, near the epicenter off the Chilean coast, official accounts indicate over 156 fatalities due to the tsunami. Preliminary measures of a Rapid Survey Team deployed the week after the event by UNESCO showed run up measurements as high as 30 meters with most common measurements between 6 and 10 meters in the most affected area of the Chilean coast. This earthquake and tsunami event presented an ideal opportunity to assess the performance of the PTWS. To that end the UNESCO/IOC Secretariat for the PTWS sent out a post-event survey questionnaire to the Tsunami Warning Focal Points (TWFPs) and Tsunami National Contacts (TNCs) from its 32 Member States and territories. This report has been prepared by the Secretariat based on the responses received from 19 TWFPs and TNCs. Factual details of the earthquake event and the tsunami are presented and the results of the survey are listed in tables and displayed as timelines and maps. We underscore that all TWFPs received the first PTWC bulletin. In addition, most of the countries reported PTWC as source of awareness of the earthquake. Fourteen countries issued a tsunami warning and in 9 Member States coastal zones were evacuated. It would be pertinent that each Member State analyze if an evacuation would have been necessary in zones where no evacuation was made. In four countries, some areas were evacuated preventively (self-evacuation). Moreover, it was observed that sea level was monitored by most of the countries. In addition, some countries used results from numerical modelling and calculated earthquake parameters. Based on data and information collected from Member States the PTWS acted promptly and efficiently throughout the Pacific. However, and at the same time, this event demonstrated the need to reinforce the work of PTWS for near field events, particularly with denser sea level real time networks close to active subduction areas. Indeed, as it has been demonstrated by the case of the sea level station located in Talcahuano, Chile, sea level stations close to the epicenter may be partially or totally destroyed by the impact of an earthquake and/or a tsunami. Given the critical role sea level readings have in all tsunami warning systems, the sea level monitoring networks should be densified close to active subduction areas and redundancy of sensors and transmission paths be strongly considered. Most of the issues revealed by the survey can be addressed both by the PTWS and at the national level through increased regional cooperation and training where needed. Post-event assessments assist in this process by highlighting the strengths and weaknesses of the PTWS at regional, national and local levels and by raising the awareness of how Member States responded, both individually and collectively. The true value of such assessments is that it allows Member States to share information and experiences for the mutual benefit of improving the PTWS performance for all members.
    • 12 January 2010 Haiti Earthquake and Tsunami Event : Post-Event Assessment of CARIBE EWS Performance.

      Aliaga, Bernardo; Yamamoto, Masahiro; Mosquera, Diana Patricia; Intergovernmental Oceanographic Commission (UNESCO-IOCParis, France, 2010)
      The 26 December 2004 tsunami in the Indian Ocean killed over 230,000 people, displaced more than 1 million people and left a trail of destruction. Considering that the Caribbean is a region prone to tsunamis, and recognising the need for an early warning system, the Intergovernmental Coordination Group (ICG) for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS) was established in 2005 as a subsidiary body of the IOC-UNESCO with the purpose of providing assistance to all Member States of the region to establish their own regional early warning system. The main objective of the CARIBE EWS is to identify and mitigate the hazards posed by local and distant tsunamis. The goal is to create a fully integrated end-to-end warning system comprising four key components: hazard monitoring and detection; hazard assessment; warning dissemination; and community preparedness and response. The Pacific Tsunami Warning Centre (PTWC) in Hawaii is the interim tsunami warning service provider for the Caribbean. The West Coast and Alaska Tsunami Warning Centre (WC/ATWC) is providing tsunami warning service for the USA territories in the Caribbean region. The magnitude 7.0 earthquake in Haiti on the 12 January 2010 was one of the most severe earthquakes that occurred in this country in the last 100 years. It caused a large number of casualties and material destruction.In addition, the earthquake generated a tsunami that caused a runup of 3m at both Jacmel and Petit Paradis, Haiti and 1m in Pedernales, Dominican Republic. Furthermore, it was recorded with an amplitude of 12 cm (peak to trough) at the Santo Domingo sea level station in the Dominican Republic. The arrival time was at 22:40 UTC, namely 47 minutes after the earthquake occurred. This tsunami recalled the need to effectively implement the CARIBE EWS to be prepared for future potentially destructive tsunamis in the region. The event therefore presented an ideal opportunity to evaluate the performance of the CARIBE EWS to highlight both the strengths and weaknesses of the system, to identify areas that require further attention, and to provide a benchmark of the present status of the system. The UNESCO IOC Secretariat for the CARIBE EWS sent out a post-event survey questionnaire to Member States and territories that have identified their Tsunami Warning Focal Points (TWFP). Out of 28 questionnaires sent out, 23 responses were returned to the CARIBE EWS Secretariat in Paris. The objectives of the survey were to confirm that the NTWCs received bulletins from the interim advisory service in a timely manner, to determine what actions were taken by the NTWCs, and to find out if the Member States activated their emergency response plans based on the available information. The survey was very useful to get an overview of the current status of the CARIBE EWS. Tsunami bulletins were received timely by most of the countries that answered the survey. On the other hand, it was identified that sea level was scarcely monitored during the event, and that some National Warning Centres (NWC) do not know how to access sea level data over the GTS or over the IOC Sea Level Observation Facility website. Most NWCs did not use any numerical models during the event. It was observed, as well, that countries placed in watch level were able to distribute warnings and even preventively evacuate some areas. It is beyond the scope of this report to conduct a detailed interpretation of the results, and the survey results have been presented so that individual Member States and the ICG can draw conclusions from this exercise and decide on future action. Although progress has been made since 2005, it should be recognized that the CARIBE EWS is not yet fully implemented and much remains to be done to bring the system to full operational status. The ICG will continue to monitor the system to ensure continuous improvement during the development phase.
    • Global Sea-level Observing System (GLOSS) Implementation plan – 2012.

      Merrifield, Mark; Holgate, Simon; Mitchum, Gary; Pérez, Begoña; Rickards, Lesley; Schöne, Tilo; Woodworth, Philip; Wöppelmann, Guy; Aarup, Thorkild; Intergovernmental Oceanographic Commission (UNESCO-IOCParis, France, 2012)
      The Global Sea-level Observing System (GLOSS) was established by the Intergovernmental Oceanographic Commission (IOC) of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in 1985 to provide oversight and coordination for global and regional sea-level networks in support of scien- tific research. The first GLOSS Implementation Plan (GIP) in 1990 established the GLOSS Core Network (GCN) of ~300 tide gauges distributed around the world, technical standards for GLOSS tide gauge stations, as well as the basic terms and obligations for Member States participating in GLOSS. The second GIP in 1997 expanded the GLOSS programme to include sub-networks focused on long historical records suitable for the detection of long-term sea- level trends and accelerations (GLOSS-LTT), a cali- bration network for satellite altimetry (GLOSS-ALT), and a network suitable for monitoring aspects of the global ocean circulation (GLOSS-OC). In addition, a strategy for integrating Global Positioning System (GPS) into monitoring of land levels at GLOSS tide gauges was developed. The focus of the GIP 2012 remains the GCN and the datasets that result from this network. The new plan calls for two significant upgrades to the GCN moti- vated by scientific and operational requirements: 1) all GCN stations are required to report data in near-real time, which will be tracked at a Sea-level Station Monitoring Facility. This will involve upgrades in power, data acquisition plat- forms, and communication packages; however, these upgrades are cost-effective in terms of the benefits that a real-time system will provide for ocean monitoring and improved station perfor- mance due to early detection of station malfunc- tions; 2) continuous measurements of the Global Navigation Satellite System (GNSS), in particular the U.S. Global Positioning System (GPS), the Russian GLONASS, or the newly established European GALILEO, or equivalent systems, in the vicinity of the tide gauge benchmark (TGBM) are required for all GCN stations. This upgrade will support satellite altimetry calibration and research efforts aimed at determining geocentric global sea-level rise rates as well as regional changes in sea level. Most relevant, vertical land movements can signifi- cantly alter the rates of sea-level rise expected from the sole climatic contributions of ocean ther- mal expansion and land-based ice melting, possi- bly magnifying the impacts of sea-level rise on the coast. In many cases, this requirement can be met by taking advantage of existing GNSS receivers maintained by other groups, as long as a precise geodetic tie to the GCN tide gauge can be made using, e.g. conventional levelling. The organization of the plan is as follows. An over- view of the GLOSS programme (chapter 1) and a brief summary of the uses of tide gauge data (chapter 2) are presented. The current status of the GLOSS programme is considered (chapter 3), followed by a discussion of the sea-level monitoring requirements raised by advisory groups and panels (chapter 4), as well as a self-assessment based on specific research and operational applications (chapter 5). These requirements are used to develop implementation goals for the GLOSS networks and data centres (chapter 6). Minor modifications are proposed for the administrative structure of GLOSS aimed at providing improved oversight of the imple- mentation plan (chapter 7). The success of the plan depends critically on the participation of Member States, whose obligations are summarized (chapter 8). The successful Training, Education and Mutual Assistance programmes that have been a corner stone of GLOSS will be continued to help meet implementation requirements (chapter 9). Additional technical and programmatic details are included in a set of appendices.
    • Exercise NEAMWAVE 12: A Tsunami Warning and Communication Exercise for the North-eastern Atlantic, the Mediterranean, and Connected Seas Region. Volume 1. Exercise Manual.

      Intergovernmental Oceanographic Commission (UNESCOParis, France, 2012)
      In every ocean, regional and national tsunami warning systems must maintain a high level of readiness so as to be able to efficiently and effectively act to provide for the public’s safety during fast-onset and rapidly-evolving natural disasters involving marine inundation of coastal areas. Because of the relative infrequency of tsunamis, but knowing that tsunamis can have widespread impact across oceans and seas, the UNESCO/IOC and its Member States have been advocating through their Intergovernmental Coordination Groups (ICGs) for the regular conduct of tsunami exercises. To maintain a high state of operational readiness, National Tsunami Warning Centres (NTWCs) and Civil Protection agencies (CPA) must regularly practice their emergency response procedures to ensure that vital communication links work seamlessly, and that agencies and response personnel know the roles that they will need to play during a real event.
    • Medium-term Strategy, Pacific Tsunami Warning and Mitigation System (PTWS MTS) 2014–2021.

      Intergovernmental Oceanographic Commission (UNESCO-IOCParis, France, 2013)
      The PTWS Medium-Term Strategy (PTWS MTS) outlines the vision of a continuously improving Pacific Tsunami Warning and Mitigation System (PTWS) to meet stakeholder requirements during the period 2014–2021. This MTS is aligned with the eight year cycle of our parent body’s Medium–Term Strategy. The Intergovernmental Oceanographic Commission (IOC) MTS (Resolution XXVII-2, part B) identifies early warning systems as an important part of its strategic vision and has aligned its MTS with the strategic planning cycle of the United Nations Educational, Scientific and Cultural Organization (UNESCO). The PTWS MTS focuses on describing general and essential strategic objectives to ensure an effective and efficient tsunami warning and mitigation system that is interoperable wherever possible with the other ocean basins and seas. The structure of the PTWS Working Group (WG) derives from the PTWS MTS and is described in the PTWS Working Group Structure document (ICG/PTWS-XXIII, Annex VI). Details of the methods of accomplishing these strategic objectives are defined in the PTWS Implementation Plan (version 2, 2001, draft document, IOC Technical Series No 86).
    • Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacents Regions (CARIBE-EWS), Implementation Plan 2013–2017. Version 2.0.

      Intergovernmental Oceanographic Commission (UNESCO-IOCParis, France, 2013)
      This current version of the Implementation Plan (ImpPlan) 2013–2017 updates on the status of the system, specifications of the requirements for designing and establishing the system for Tsunami and Other Coastal Hazards Warning System in the Caribbean and Adjacent Regions (CARIBE-EWS). It incorporates the work and views of the Intergovernmental Coordination Group (ICG) and of the sessional and inter-sessional Working Groups (WGs), namely of the WG 1 (Monitoring and Detection Systems, Warning Guidance), of the WG 2 (Hazard Assessment), of the WG 3 (Warning Dissemination and Communication), and of the WG 4 (Preparedness, Readiness and Resilience). The structure of the ImPlan is based on the participation of each WG in the development of the Early Warning System (EWS). The 2008–2011 ImPlan proposed two phases of implementation. The Initial Phase involved the real-time seismic and sea level data exchange between existing Regional Seismic Networks (RSN) followed by the establishment of one or more Caribbean Tsunami Information Center (CTIC) and one or several regional tsunami warning centres (RTWC). The Second Phase CARIBE-EWS (Fully-fledged CARIBE-EWS) was to focus on the full development of the Early Warning System, which would cover both distant and local earthquake generated tsunamis and, as science permits, tsunamis generated by volcanic activity or by landslides, in cooperation with regional networks with this area of expertise. Currently, the first phase can be considered to almost have been met. The new ImPlan will thus focus on the second phase including: (1) Vulnerability, (2) Hazard Assessment, (3) Monitoring and Detection Systems, (4) Tsunami Services, and (5) Public Awareness, Education and Resilience. It is to be noted that the implementation of the CARIBE-EWS is a complex process involving the Member States through their agencies and institutions as well as international organizations and local communities. In addition to the ICG Working Groups, the tasks are also to be completed thru task teams. This complexity implies that changes and on-the-way corrections are to be taken into account for this Implementation Plan in the course of the realization of the system, since implementation priorities, requirements or details may have to be adapted to new circumstances. Hence, the Implementation Plan will be at the same time a reference document, providing guidelines; and a dynamic document, reflecting the current status of the implementation of the Tsunami Warning System (TWS) at a given time. Updated versions of the Implementation Plan will be maintained at the Intergovernmental Oceanographic Commission (IOC) website and distributed at ICG/CARIBE-EWS sessions.
    • Tsunami public awareness and education strategy for the Caribbean and Adjacent regions.

      Intergovernmental Oceanographic Commission (UNESCO-IOCParis, France, 2013)
      The Tsunami Public Awareness & Education (PAE) Strategy for the Caribbean and Adjacent Regions forms part of the Enhancing Resilience to Reduce Vulnerability in the Caribbean (ERC) initiative, funded by the Italian Development Cooperation (Government of Italy). The project’s core outputs include the establishment of a sustainable network of real-time decision support centres to facilitate early warning and post-disaster recovery; strengthened national disaster mechanisms to incorporate best practices in volunteerism; enhanced institutional capacities; and enhanced public awareness and education programmes for tsunamis and other coastal hazards. This Tsunami Public Awareness and Education Strategy focuses on building long-term education and awareness on how to prepare and respond to tsunamis for countries in the Caribbean and adjacent regions1. It concentrates on planning and preparedness rather than providing guidelines to manage crisis communications during a disaster. Earthquakes2 and other coastal hazards are also addressed since many countries are affected by hurricanes, coastal flooding, storm surges and landslides. Indeed, long-term success of this strategy will require strong correlation between public awareness and emergency responses to tsunamis, earthquakes and other coastal hazards. This is the first time that a tsunami awareness and educational strategy of this scope and magnitude has been developed for this region. It is the result of over seven months of extensive research, analysis and consultation with over 30 stakeholders during 2012 and 2013. Once this communications strategy is validated, a harmonized approach to tsunami public awareness and education can be used by countries and territories from the Caribbean and adjacent regions. Long-term implementation results of this framework are expected to standardize messaging, increase information flow, strengthen cooperation, and bring regional continuity amongst countries and partners. Tsunami education and awareness are made within the context of broader disaster risk reduction (DRR) initiatives including the establishment of a Caribbean Tsunami Information Centre (CTIC), and building and sustaining disaster resilience as a shared responsibility across the region. It is also expected to complement other public awareness and education (PAE) work being done in each of the countries. Global initiatives that underpin this framework include several priorities in the Hyogo Framework for Action (HFA), the Post−2015 Framework for DRR, and the Post−2015 Development Agenda that will supersede the Millennium Development Goals (MDGs). Regional initiatives that also affect this document are the sustainable development agenda for the 2014 International Conference of Small Island Developing States, and the Regional Stakeholder Consultation on the Comprehensive Disaster Management (CDM) Strategy Beyond 2012 of the Caribbean Disaster Emergency Management Agency (CDEMA). This document uses as a starting point the 2009 Tsunami Smart® PAE Strategy initially drafted by CDEMA with input from several stakeholders, including the Seismic ResearchCentre (SRC). The Tsunami Smart® Strategy remains a good “How-To” manual for PAE Officers. The current strategy takes into account lessons learned from recent disasters, and integrates feedback from PAE practitioners in all relevant regions, particularly from Central and South America. It also incorporates lessons learned and best practices from the early warning component of the implemented Regional Risk Reduction Initiative (R3I) of the United Nations Development Programme (UNDP) for 11English and Dutch Overseas Countries and Territories (OCTs) and the US National Tsunami Hazard Mitigation Program (NTHMP). This communications strategy proposes that certain target audiences are more in need of public awareness and education than others. The following four areas were chosen so as to generate the highest potential public awareness impact which consequently would lead to the highest possible return on investment. These four communication approaches are listed below followed by the intended audience(s), in brackets:  Curriculum integration (education sector);  Specialized training (media, teachers, first responders, PAE professionals);  Community participation and input (multiple stakeholders);  Country/community designation or recognition by a program such as Tsunami Ready®. Communities could also become designated as “Marine and Coastal Hazards Ready”. If designation or recognition is not possible, at a minimum, install unaffiliated tsunami or other coastal hazard signage on key public beaches (tourism and private sectors, residents). Some of the strategic concepts discussed in this document include:  The changing role of a communicator from ‘implementer’ to ‘leverager’ and the resulting need for more partnerships, coordination of existing resources, and sharing information effectively, efficiently, and with the least cost.  The need for resource utilization that can be achieved through leveraging and content iteration rather than duplication.  The need to advocate for citizens to share the responsibility and take accountability for their own awareness. It is more than just the responsibility of the National Disaster Office (NDO) or PAE officers /governments.  The need for buy-in. PAE cannot work in isolation. It needs support from the National Disaster Office authorities, Ministers and Cabinet, elected officials, other key departments and from the media. Strong and exercised standard operating procedures (SOPs), policies and legislation are required to guide communications, particularly during emergencies.  The acknowledgement that this strategy focuses on long-term awareness and education on tsunamis to a variety of stakeholders rather than providing guidelines on doing crisis communications during a disaster.  The need to measure progress on projects and activities and take the pulse of the community at regular intervals. The strategy is not prescriptive because a one-size-fits-all formula that will work best for all countries does not exist. Each island/country is unique with unique economic, political, cultural factors that guide in the implementation of PAE. This strategy provides each country and territory with overall guidance and a range of options. It is then incumbent upon eachjurisdiction to do the due diligence using environmental and national analyses3 to adapt this framework to regional/local experiences and realities. This allows flexibility to prioritize target groups, approaches and tools/processes according to available resources. This Tsunami PAE Strategy identifies key areas that are common to all and which could have powerful multiplier effects when adapted and utilized by a majority of countries and territories in the region. It is acknowledged however that changing public perception and behaviour takes time. Behavioural communication guidelines show that real change requires about five years to begin to notice differences, and close to ten years for sustainable change. This could also be approximately the same number of years it could take to add or change a country’s educational curriculum. This reinforces the need to undertake continuous evaluation of the PAE already completed and to update this Tsunami PAE Strategy every two to three years.
    • Directory of Atmospheric, Hydrographic and Biological datasets for the Canary Current Large Marine Ecosystem

      Déniz-González, Itahisa; Pascual-Alayón, Pedro J.; Chioua, Jamal; García-Santamaría, M. Teresa; Valdés, Luis (IOC-UNESCOParis, France, 2014)
      The Canary Current Large Marine Ecosystem (CCLME) is a major upwelling region off the coast of northwest Africa. A total of 425 datasets, 27 databases and 21 time-series sites have been identified in the area. A substantial part of them were rescued from archives supported in paper copy. The current directory refers to 85 datasets, databases and time-series sites. This catalogue and the recovered data offer an exceptional opportunity for the researchers in the CCLME to study the dynamics and trends of a multiplicity of variables, and will enable them to explore different data sources and create their own baselines and climatologies under a spatial and temporal perspective.
    • Recent changes and trends of the upwelling intensity in the Canary Current Large Marine Ecosystem

      Benazzouz, Aïssa; Demarcq, Hervé; González-Nuevo, Gonzalo; Valdés, Luis; Déniz-González, Itahisa (IOC-UNESCOParis, France, 2015)
      We provide a summary of current knowledge for the recent trends of the coastal upwelling intensity in the region from 8°N to 43°N, computed from both wind and sea surface temperature (SST) remotely sensed, from 1982 to 2011. In particular, the impact of changes possibly linked to global warming is estimated in the form of spatial linear trends. Statistical analysis of trends and seasonal changes of the upwelling activity are carried out in order to verify the hypothesis of Bakun (1990), which anticipates an intensification of the upwelling favorable winds and therefore a cooling of coastal waters. Our study brings new insights on the spatial patterns of the changes. The results indicate distinct and questionable trends of the two categories of upwelling indices, in a region associated with a strong SST warming, especially in the southern part of the system. While the central and southern parts of the system display an increase of upwelling-favorable winds, no significant upwelling trend is found in the same sub-regions from SST-based upwelling indices. It is stated that changes in the internal structure of the upper ocean, as a result of global warming, may be responsible of such differences: a significant warming of the surface upwelled waters possibly combined with a thickening of the surface mixed layer.
    • Organic matter dynamics in the Canary Current

      Álvarez-Salgado, Xosé Antón; Arístegui, Javier; Valdés, L.; Déniz-González, I. (IOC-UNESCOParis, France, 2015)
      The distribution and cycling of biogenic organic matter in the Canary Current Large Marine Ecosystem is strongly affected by the intense mesoscale activity of the area, mainly in the form of meanders, filaments and eddies, and their interaction. Filaments contribute significantly to the offshore export of coastal upwelling primary production in the form of dissolved and suspended organic matter. Cyclonic and anticyclonic eddies (mostly generated by flow perturbation by Madeira and the Canary Islands) may enhance the production of fresh organic matter during their early stages of formation, favouring the vertical sinking of particles. Additionally, they may accumulate and transport suspended particles and dissolved organic matter through a permanent westward corridor of eddies. Organic matter deposited in coastal sediments is also transported laterally to the adjacent ocean in the form of intermediate and bottom nepheloid layers resulting from the erosion of the shelf and slope sediments by the intense and variable coastal currents. All these mechanisms contribute exporting the biogenic materials produced in the coast hundreds of kilometres into the open ocean.
    • Sea turtles off Northwest Africa

      Marco, Adolfo; Martins, Samir; Valdés, L.; Déniz-González, I. (IOC-UNESCOParis, France, 2015)
      Six sea turtle species inhabit the waters of the Canary Current Large Marine Ecosystem. The loggerhead and the green turtles are the most common and the only two species that nest regularly on its beaches (loggerheads in Cape Verde and greens in the Bijagós islands, Guinea-Bissau). The Kemp’s ridleys, the most restricted and endangered in the world, are very rare although migrant juveniles can be found along the northwestern coast of Morocco. Leatherbacks, hawksbills, and olive ridleys can be also found in the waters of the CCLME. Most of adult move after nesting to the continental African coast to feed. Some green females migrate from Poilão (Guinea-Bissau) to the Park National du Banc D’Arguin (Mauritania). Moreover, there is an important feeding area for leatherback turtles coming from the American coast. Small juvenile turtles are known to disperse extensively on a transatlantic scale and are commonly associated with convergence zones, upwellings, major gyre systems, and eddies. Increasing fishing efforts worldwide and marine debris put all sea turtle species at risk. The high concentration of turtle nesting on small beach stretches makes the population extremely vulnerable to any kind of environmental disaster. Turtle-watching activities are known as important alternative sources of income for local communities.
    • Biodiversity and biogeography of decapods crustaceans in the Canary Current Large Marine Ecosystem

      García-Isarch, Eva; Muñoz, Isabel; Valdés, Luis; Déniz-González, Itahisa (IOC-UNESCOParis, France, 2015)
      Decapods constitute the dominant benthic group in the Canary Current Large Marine Ecosystem (CCLME). An inventory of the decapod species in this area was made based on the information compiled from surveys and biological collections of the Instituto Español de Oceanografía. A total number of 228 species belonging to 54 families were registered. Brachyura, with 87 different species was the most diversified taxa, followed by Caridea and Anomura with 61 and 33 species, respectively. The high diversity of this group in the CCLME is favoured by the presence of typically temperate species in the North (Morocco-Western Sahara), subtropical-temperate species from Morocco to Mauritania, and typically tropical species in the South (Guinea-Bissau‒Guinea). The diversity in the most temperate and northern zone was higher than in the most tropical and southern zone, with exceptionally high values in Mauritania mainly explained by its special biogeographic and oceanographic conditions. Some decapod species have been exploited by both artisanal and industrial fisheries for decades, providing significant incomes to the coastal states. However, the intense shrimp fishing activities have some negative effects like the overexploitation of certain stocks and the impact on benthic communities by disturbing their physical structures and habitats.
    • Pelagic fish stocks and their response to fisheries and environmental variation in the Canary Current Large Marine Ecosystem

      Braham, Cheikh-Baye; Corten, Ad; Valdés, L.; Déniz-González, I. (IOC-UNESCOParis, France, 2015)
      Pelagic fish stocks are the most important fish stocks in terms of biomass and catches in the Canary Current Large Marine Ecosystem. The small pelagic stocks include species with an affinity for temperate waters (sardine, chub mackerel and Atlantic horse mackerel) and species that prefer tropical waters (sardinella and Cunene horse mackerel). Hence, the distribution of the various stocks is strongly determined by the seasonal displacement of the tropical front. As small pelagic fish feed primarily on plankton, changes in primary production may affect the abundance of the stocks. The waters of the Canary Current have shown a drop in primary production over the past three decades, which may be related to the observed increase in water temperature. However, the drop in primary production is not yet reflected by the pelagic fish catches. On the other hand, changes in the abundance and distribution of sardine and sardinella are probably the effect of climatic change. Present management of small pelagics is hampered by a lack of scientific data. Because these stocks are very important to the human population of the region, good quality data should be collected in order to improve the assessments.
    • Zooplankton in the Canary Current Large Marine Ecosystem

      Berraho, Amina; Somoue, Laila; Hernández-León, Santiago; Valdés, Luis; Valdés, L.; Déniz-González, I. (IOC-UNESCOParis, France, 2015)
      Copepod species in the CCLME accounted for 60-95% of the zooplankton abundance being the bulk of the mesozooplankton biomass. Two main groups of copepod species can be identified, representing biogeographical and ecological characteristics: tropical and subtropical species, related to a sub region with a low influence of the upwelling nutrient enriched waters (Cape Verde, Canary Islands and Cape Blanc); and subtropical and luso-boreal species identified along the Northwest Africa coast (Cape Spartel-Cape Blanc) with a strong seasonality of upwelling and coastal nutrient rich waters. A succession from small to medium and large calanoids and gelatinous organisms from the upwelled waters to the ocean is the rule and this pattern is coupled with a switch of the feeding mode of the zooplankters. A phytoplankton-based diet was observed in the inshore upwelling zone whereas a microzooplankton based diet was observed offshore under more oligotrophic conditions. More studies are needed to verify that the patterns observed in zooplankton composition and distribution 30-35 years ago are still valid and that climate change and variability of upwelling strength is neither altering the cycles nor the productivity of the CCLME. Also the zooplankton physiology deserves future work as these organisms live longer than any other plankton and are the food of diel vertical migrants (large zooplankton and micronekton).
    • Waves and tides in the Canary Current Large Marine Ecosystem

      Gómez, Marta; Pérez-Gómez, Begoña; De Alfonso, Marta; Pérez, Susana; Ruiz, Mª Isabel; Valdés, L.; Déniz-González, I. (IOC-UNESCOParis, France, 2015)
      In recent decades, and in parallel to the increase in the computational capabilities and improvements in telecommunications, a remarkable progress in the development of equipment for marine environment monitoring has been carried out. Many countries are implementing permanent measurement networks, as well as climate forecast and data management systems. The information generated by these tools is distributed to the whole society. This article describes waves and tides regime and variability in the Canary Current Large Marine Ecosystem (CCLME). The study is based on those sources of data with adequate and relevant information (products) that allow a reasonable description of these two oceanographic variables, being Puertos del Estado equipment and numerical models the main source of information. A review of existing buoys, tide gauges and numerical models available in the region was performed by contacting different institutions from the affected countries as well as international organizations.
    • Harmful algal bloom events in the Canary Current Large Marine Ecosystem

      Pitcher, Grant C.; Fraga, Santiago; Valdés, L.; Déniz-González, I. (IOC-UNESCOParis, France, 2015)
      We provide a review of Harmful Algal Blooms (HABs) within the Canary Current Large Marine Ecosystem (CCLME). As yet all documented HABs within the region have been associated with the production of one or another toxin. The diversity of harmful algae recorded within the region is similar to that found in other eastern boundary upwelling systems, and includes those species responsible for paralytic shellfish poisoning, diarrhetic shellfish poisoning, amnesic shellfish poisoning and azaspiracid poisoning. Also present off Northwest Africa, but generally absent from the other major upwelling systems, are those species responsible for ciguatera fish poisoning and microcystin-producing cyanobacterial blooms. Their presence is afforded by the subtropical habitat provided by the island archipelagos found within the CCLME. It is intended that this brief review will provide the foundation and stimulus for further studies of the ecology and dynamics of HABs, of their toxins, and of the public health and socioeconomic impacts of HABs within this region.
    • Main geomorphologic features in the Canary Current Large Marine Ecosystem

      Agudo-Bravo, Luis M.; Mangas, José; Valdés, L.; Déniz-González, I. (IOC-UNESCOParis, France, 2015)
      The Canary Current Large Marine Ecosystem shelf has the typical size and composition, of passive continental margins. In general, it has a mean width between 40-50 km, with exceptions like Bank D´Arguin or Dakar. The maximum age of the sedimentary rocks is 200 Ma. The geomorphological variations are the result of the sedimentary contributions associated to the river basins, which also influence the genesis and presence of canyons in the shelf and slope. These canyons are the main geomorphological features in the region. Seamounts, salt domes, pockmarcks and gravitational processes like debris flows are also observed. The tectonic processes are generally extensive, but have a small influence. It is remarkable the presence of a coral reef with more than 400 km of length in the shallowest Mauritania slope. The geomorphological studies in the intraplate volcanic islands (Canary Islands and Cape Verde), confirm the presence of developed shelves in the older islands, not observed in the younger ones. There are gravitational slides and canyons in all the islands. The region was divided in 4 areas: Morocco–Western Sahara; Mauritania; Canary Islands; and Senegal –Gambia –Guinea–Bissau – Guinea–Cape Verde. Within each of these areas, different geomorphological and geological domains are described.
    • Eastern boundary currents off North-West Africa

      Pelegrí, Josep L.; Peña-Izquierdo, Jesús; Valdés, L.; Déniz-González, I. (IOC-UNESCOParis, France, 2015)
      The Cape Verde Front (CVF) separates the North Atlantic subtropical gyre (NASG) from the north-eastern North Atlantic tropical gyre (NATG). Within the NASG, the Canary Current (CC) and the Canary Upwelling Current (CUC) comprise a relatively shallow (down to about 200-300 m) flow of North Atlantic Central Waters (NACW): the CC is found far offshore as a wide and poorly defined current while the CUC is a near-slope intense baroclinic jet linked to the coastal upwelling front. Within the top 300 m of the NATG, the along-slope Mauritania Current and the Cape Verde Current (CVC, a north-eastern extension of the North Equatorial Counter Current that broadly rotates around the Guinea Dome) carry South Atlantic Central Waters northwards. As a result, the frontal system is the site of intense along-slope flow convergence and offshore transport in the top 300 m of the water column. Further deep, down to some 500 m, the interior flow is very weak in both gyres, likely dominated by mesoscale features, except along the continental slope, where the northward Poleward Undercurrent (PUC) feeds through localized inputs from the interior ocean; in particular, within the NATG the CVC appears as responsible for southward transfer of NACW, across the CVF, which eventually reaches the PUC.
    • Biodiversity of cetaceans in coastal waters of Northwest Africa: new insights through platform-of-opportunity visual surveying in 2011-2013

      Djiba, Abdoulaye; Bamy, Idrissa Lamine; Samba Ould Bilal, Abdellahi; Van Waerebeek, Koen; Valdés, Luis; Déniz-González, Itahisa (IOC-UNESCOParis, France, 2015)
      We summarize diversity, group size and habitat of cetaceans documented through ship-based visual survey effort (13,694 km; 1163.5 h) off NW Africa (Conakry to Tangier) in spring and fall of 2011-2013. Study area covered mainly continental shelf with some slope waters. Platform-of-opportunity surveying yielded 270 primary sightings of 14 species. Due to passing mode, 35.7% were identifiable only to family/category: unidentified Delphinidae (25.0%), unidentified rorquals (5.88%) and unidentified whales (4.78%). Delphinus delphis predominated with 28.7% of total sightings (32.7%, including probable) and a massive 71.3% (76.5%) of total number of cetaceans observed (n=15,595). Encounter rate was 81.2 common dolphins 100 km-1; mean group size 124.92. Tursiops truncatus, primarily inshore ecotype (median depth, 44.5 m), accounted for 9.56% (11.4%) of sightings and 1.35% (1.83%) of total cetaceans. Megaptera novaeangliae (6.25%) was regularly seen south of Dakar with a Southern Hemisphere seasonality. Other species showed a relatively low % occurrence: Globicephala spp. (2.57), Orcinus orca (1.10), Grampus griseus (0.73), Stenella frontalis (1.84), S. attenuata (0.37), S. clymene (0.37), S. coeruleoalba (0.37), Balaenoptera brydei (1.10), B. musculus (0.37), beaked whale (0.37), probable-B. borealis (0.37). Baleen plates recovered from a bottom-trawl also evidenced B. borealis presence. Seven new range state records included: G. griseus, S. coeruleoalba (Atlantic Morocco), O. orca, B. musculus (The Gambia), G. macrorhynchus, S. frontalis (Guinea-Bissau), S. attenuata (Guinea).