World Meteorological Day |23 March 2021
Ocean’s tight linkage with atmosphere vital for forecasting weather and climate conditions
When it comes to weather and climate, most of us think only about what is happening in the atmosphere. However the ocean cannot be ignored as its tight linkage with the atmosphere makes understanding its behaviour vital for forecasting weather and climate conditions.
This year’s World Meteorological Day theme ‘The Ocean, our climate and weather’ focuses on connecting the ocean, climate and weather within the earth system. It also marks the launch of the United Nations Decade of Ocean Science for Sustainable Development (2021-2030). The decade galvanises efforts to gather ocean science – through innovative and transformative ideas ‒ as the basis of information to support sustainable development.
Covering some 70% of the earth’s surface, the ocean is a major driver of the world’s weather and climate. It also plays a central role in climate change. The ocean is also a major driver of the global economy, carrying more than 90% of world trade and sustaining the 40% of humanity that lives within 100 m of the coast. Recognising this, national meteorological and hydrological services and researchers regularly monitor the ocean and how it is changing, modeling how it affects the atmosphere and delivering a wide variety of marine services, including supporting coastal management and safety of life at sea. Today, the growing impacts of climate change are making ocean observations, research and services more critical than ever before.
Weather forecasters combine ocean observations and knowledge of how ocean-atmosphere interactions shape weather, seasonal and long-term climate and ocean patterns with observations of temperature (atmospheric and sea surface), atmospheric pressure, wind, waves, precipitation and other variables. Together, these data sets become key input in coupled numerical weather and climate prediction models. The World Meteorological Organisation (WMO) community therefore has a major stake in supporting ocean observations, research and services.
To monitor the present state of the ocean, and track how the ocean is warming and changing, WMO co-sponsors the Global Ocean Observing System (GOOS), along with the Intergovernmental Oceanographic Commission (IOC) of the United Nations Educational, Scientific and Cultural Organisation (Unesco), the United Nations Environment Programme (Unep) and the International Science Council (ISC). This coordinated system encompasses networks of buoys, ships, and other observations.
In view of the vast ocean territory of the Seychelles archipelago, ocean observation in Seychelles can be viewed as a field of great importance.
Sea level monitoring in Seychelles dates back to the early 1960s, with the initial measurement being taken from Ile Hodoul of Port Victoria.
In 1986 the Hydrographic and Topographic brigade of the Seychelles installed a new tide gauge at the New Port in Victoria. The tide gauge was later moved to the Seychelles Coastguard headquarters, whereby it was administered and maintained by the coastguard personnel.
Several ad-hoc sea level measurements by the Hydrographic and Topographic brigade of the Seychelles was also conducted during the year 1991 at different locations throughout the archipelago, as part of a survey being conducted then, to map out the Seychelles exclusive economic zone (EEZ).
The Seychelles Meteorological Authority (SMA) together with its international and local partners have deployed several sea level and ocean monitoring systems with the aim to measure real-time oceanographic parameters and collect data sets for research purposes.
In 1993, a sea level monitoring station under the Tropical Ocean Global Atmosphere (TOGA) Sea Level Centre programme was installed at the Seychelles International Airport. The tide gauge station has been maintained since then by the personnel of the Seychelles Meteorological Authority (SMA), under the guidance of the University of Hawaii Sea Level Centre (UHSLC) remote field engineer. The station has been operational since 1993 and relays reliable sea level data in near real-time to UHSLC via satellite telemetry.
In 2016, the Indian National Centre for Ocean Information Services (INCOIS), as part of the integrated ocean information system for the Indian Ocean countries deployed a wave rider buoy in the Seychelles, in the vicinity of Fregate island.
The integrated ocean information system was established by INCOIS through a technical cooperation with the Regional Integrated Multi-Hazard Early Warning System for Africa and Asia (RIMES). Successful deployment of the wave rider buoy in the Seychelles was made possible through the involvement of the SMA and its local partners.
In 2018, as part of the Monitoring for Environment and Security in Africa (MESA) programme, through the funding of the European Union (EU) and implementation by the Mauritius Oceanography Institute (MOI), a second ocean buoy was installed in the inner waters of the Seychelles archipelago. The new buoy was installed about 5 kilometres from the shore of the coastal district of Bel Ombre on the island of Mahé.
The buoy contributes towards improving the institutional capacity of institutions mandated with marine and coastal management roles. The data transmitted in real-time via global system for bobile (GSM) and satellite telemetry and accessible via the world wide web, allows for the monitoring and mitigation of ocean related risks such as swells, storm surge and sea-level rise which may lead to coastal hazards.
The information derived from these sea level and ocean monitoring systems are extremely important for a variety of marine and coastal activities and which in future can also support the blue economy concept in relation to fishing activities and offshore industries.
Contributed by the Seychelles Meteorological Authority