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Science and Applications OC and SST. OC and SST are important variables for Climate variability, trendsWeather and ocean forecastingOcean and atmospheric models (forcing, data assimilation and validation)Primary ProductionCarbon budgetHeat transfer
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1. Ocean Time Series Data Products from Systematic Satellite Missions: Moderate Resolution - AVHRR/SeaWiFS/MODIS/VIIRS
2. Science and ApplicationsOC and SST OC and SST are important variables for
Climate variability, trends
Weather and ocean forecasting
Ocean and atmospheric models (forcing, data assimilation and validation)
Primary Production
Carbon budget
Heat transfer
3. MEI: climate variables: atmosp pressure, surface winds, SST, air temperature, cloudiness
Changes in biology (NPP) are related to climate variables.
Various satellite time-series used in the workMEI: climate variables: atmosp pressure, surface winds, SST, air temperature, cloudiness
Changes in biology (NPP) are related to climate variables.
Various satellite time-series used in the work
4. A few SST time-series
5. GHRSST-PP GODAE (Global Ocean Data Assimilation Experiment) High-Resolution SST Pilot Project
International project begun in late 2004.
To produce SST fields that contain error statistics for each SST pixel.
The traceability of the accuracy of the SST pixels through the atmospheric correction and cloud screening algorithms is important to establishing confidence in the SST fields.
Validation of satellite derived SSTs from a range of sensors, using various in situ radiometers, each with NIST-traceable calibration, is an important component of this project.
6. SST time-series More than 20 years of data
Highly successful data sets
Merged data sets (thermal IR and microwave, biases correction among sensors)
Perennial (no data gap in sight ?)
NASA MEaSUREs: Merged Ultra High Resolution (1 km) SST product
7. Ocean Color time-series (Level-3)
8. Satisfy emerging demand for validated merged ocean colour derived information
Demonstrate the current state of the art in merging together data streams from different ocean-colour sensors:
MERIS (ESA), SeaWiFS (NASA), MODIS-AQUA (NASA)
Provide a long time-series (10 years) of ocean-colour information
Demonstrate a global NRT ocean-colour service based on merged satellite data
Put in place the capacity to continue production of such time series inthe future and to prepare for full exploitation of Sentinel 3 (ESA)
As such, be the initial step of the Ocean Colour Thematic assembly Centre, part of the future EU GMES Marine Core Service
www.globcolour.info
http://www.enviport.org/globcolour/validation/
10. Ocean Color time-series (Level-3)
11. Ocean Color time-series (Level-3) Contd
12. ESDRs, CDRs and CAL/VAL
13. Climate Data Records National Academy of Sciences Report (NRC, 2000): a data set designed to enable study and assessment of long-term climate change, with long-term meaning year-to-year and decade-to-decade change. Climate research often involves the detection of small changes against a background of intense, short-term variations.
Calibration and validation should be considered as a process that encompasses the entire system, from the sensor performance to the derivation of the data products. The process can be considered to consist of five steps:
instrument characterization,
sensor calibration,
calibration verification,
data quality assessment, and
data product validation.
14. SST lots of matchup points (floats, buoys, drifters
.) limited range of variation
OC mostly measurements during cruises, often coastal, chl varies over 3 or more orders of magnitudes.
MOBY - Some challenges are common to OC and SST but some are very differentSST lots of matchup points (floats, buoys, drifters
.) limited range of variation
OC mostly measurements during cruises, often coastal, chl varies over 3 or more orders of magnitudes.
MOBY - Some challenges are common to OC and SST but some are very different
15. M-AERI cruises and MODIS validation statistics
16. ISSUES/CONCERNS
17. Ocean color time-series Bias among different time-series exist. Need to be reconcile to build ESDRs or CDrsBias among different time-series exist. Need to be reconcile to build ESDRs or CDrs
18. Long-time series measurements of SST Multi-decadal time series require accurate measurements from several series of satellites and sensors. All have particular sampling and accuracy problems:
Infrared polar orbiters (AVHRRs, (A)ATSRs, MODISs, Met-Op AVHRR/3
VIIRS):
More complex instruments (MODIS, VIIRS) leads to more instrumental artifacts
Limited degrees of freedom for atmospheric corrections
Microwave polar orbiters (AMSR-E
AMSR follow-on GCOM-W ):
Calibration issues
Footprint size
Side-lobe contamination
Infrared geostationary (GOES Imager, MSG SEVIRI
GOES-R ABI ):
No high latitude coverage
Diurnal heating cycle of s/c and instrument (3-axis GOES s/c)
19. Concerns about sustaining SST CDRs Complex instruments need very careful pre-launch characterization
Accurate validation must be sustained throughout s/c missions
Overlap of missions of ~1yr desired
20. Concerns about sustaining validation capabilities CDRs require traceability to NIST standards
For AVHRR, (A)ATSR, MODIS, AMSR-E through M-AERIs and Calibration Facilities at UM-RSMAS
M-AERIs > 10yrs old, >3500 sea-days, rely on obsolete components, need replacing
Calibration Facilities must be sustained
Ship-based radiometry for validation must be sustained into the NPOESS era
21. Objectives of this breakout Discuss the scientific questions and issues that are being addressed by existing space-based observations.
Discuss current time series data products and their scientific application
Discuss their future as Climate Data Records (CDRs) and/or Earth System Data Records (ESDRs).
Discuss calibration/validation, airborne science, in situ observational needs
Identify opportunities, recommend priorities, raise issues or concerns
Questions:
What are the key products (CDR or ESDR) for understanding the ocean over time ?
What does the carbon cycle and ecosystems community and modelers expect or need of this effort?
What are our biggest challenges in this area, and how do we address them?
Is our list of identified data records complete, or is something missing?
Does the carbon cycle and ecosystems community need to establish priorities for these and other activities, and, if so, how should they be established?