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CONTENTSReport from the 9th CEPS Plenary in Canada
Australian Research Agency Chairs CEOS
CEOS Working Group on Information Systems and Services (WGISS)
CEOS and Ocean Color---This page
What is the international Group of Funding Agencies for Global Change Research (IGFA)
The Centre for Earth Observation (CEO) Technical Activities in the CEOS
Framework
Framework/CEOS Holds First Open ForumsNews Highlights/ Meeting Calendar
Summary of User Requirement Workshop
1993 CEOS Meeting Calender
CEOS and Ocean Color
John Withrow
Senior Assistant Secretary(Remote Sensing and Data Management)
Intergovernmental Oceanographic Commission(IOC)
The Ninth Session of the Committee on Earth Observation satellites
(CEOS), acting upon the recommendations of the IOC Workshop on Ocean Colour
Data Requirements and Utilization(Victoria, BC, 21-22 September 1995),
supported the formation by IOC of an International Ocean Coordination Group.
It tasked that group to coordinate relevant activities within CEOS in order
to foster the best collective use of the various ocean color sensors to
be Iaunched by different nations over the next decades.
- Australia's location in the Asia-Pacific Region will provide an opportunity
to focus attention on achievements, progress and plans for Earth observation
activities in the region.
CSIRO is Australia's premier R&D agency, with responsibility for research in fields that include communication science and engineering; minerals and energy technologies; rural and agricultural sciences; industrial technologies and environmental and natural resources. CSIRO's Office of Space Science and Applications (COSSA) is responsible for co-ordinating the Earth observation activities and has recently established the CSIRO Earth Observation Centre.
Ocean colour data are essential for monitoring and fostering our understanding of important ocean biological processes. Adequate data pertaining to ocean biological processes is extremely difficult to obtain due to the vast area of the ocean(over70%of the earth's area) and to the logistical difficulties of shipboard sampling, Satellite views of ocean colour are our only chance for gaining an overall view of the state of ocean biology at any given time, Ocean colour data is also the most practical way to develop the time-series data that will allow us to separate natural variability in ocean biological processes from secular changes.
Ocean colour data will allow us to monitor at a minimum such important areas as;biogeochemical cycles,,direct effects of biology on ocean physics, coastal resources,and fisheries sustainability. The oceans are an important net sink for carbon dioxide released by the burning of fossil fuels. However, because the great spatial and temporal variability of fluxes of carbon dioxide into and out of the ocean are poorly understood, the nature and sustainability of this critical process is unknown. It is known that the uptake of carbon dioxide is related directly to the abundance of marine algae, which can only be monitored effectively on a global scale through colour. The relative abundance of certain types of marine algae, also affect the ability of the oceans to absorb carbon dioxide by affecting the amount of calcium in the oceans, creating the potential for positive feedback between ocean warming and ocean biology.
Changes in alga abundance and species composition affect the extent to which solar radiation is absorbed or reflected by the surface ocean. Such changes will alter local and global oceanic heat budgets, with implications for both local and global climate. Trace gases produced by marine algae and released from the ocean to the atmosphere can affect local climates directly through their affect on cloudiness.
Half the worlds population lives within 100 kilometres of the ocean. This huge population has s large impact on the coastal zone. Rivers discharge large amounts of nutrients and sediments. much of it is derived from human activities, into coastal waters, affecting water quality, recreational opportunities, and coastal fisheries. Blooms of toxic algae affect human health both directly and indirectly, most notably through their effects on shellfish. Ocean colour will allow us to better detect, monitor, asses and mitigate the impacts of these events.
Ocean colour measurements will provide data to support the rational management of living marine resources including aquiculture. Fish populations aggregate at areas of discontinuity between oceanic water masses;because phytoplankton growth may change across such boundaries, ocean colour gives the capability to map the surface manifestation of structure. Utilizing such information, scientists will be able to understand more fully how fish stocks respond to this structure. They will provide the tool that will give managers enhanced capability to intelligently manage and control these living marine resources. This will contribute to the efficient use and sustainability of these resources.
The International Effort
International cooperation in satellite ocean color remote sensing of the global and coastal oceans is very timely owing to the large number of sensors planned for launch over the next 10 years. This cooperation will save money and produce the best possible local, regional and global data products to study daily to internal changes and trends in the biological characteristics of coastal and open ocean waters. The experience learned from the Japan/U.S. Working Group on Ocean Color (JUWOC), now in its sixth year of operation, suggests that an expanded effort involving more satellites and space agencies will be successful. For example, JUWOC led to coordination of OCTS and Sea WiFS sensor specifications, inter calibration of the sensors, compatible data products and formats, and cooperative calibration and validation programs leading to an exchange of key in situ observations. In addition, JUWOC meetings and symposia helped develop better ocean applications. Other successful models include the U.S. Pathfinder program for AVHRR measurements and the ISCCP program for global cloud climatologies based on data international weather satellites.
The Next Steps
The following activities are seen as critical in the nextsixtwelve months.
- 1. Continuation of the inter-calibration round robins. Closely associated
with this is the inter-calibration of national calibration standards.
2. Development of multi-sensor calibration and validation campaigns and test sites.
3. Integration of insitu measurement programs and sensor development programs. Provision for integration of insitu and remotely sensed data streams. 4. Development of multi-sensor data streams and products.
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