# Presentation: 359453

## Science enabled by new measurements of ocean properties from geostationary orbit (GEO-CAPE, etc)

- Janet W. Campbell
- University of New Hampshire
- and
- William (Barney) Balch
- Bigelow Laboratory for Ocean Sciences
- Thanks to our scribes:  Marjy Friedrichs and Paul DiGiacomo

***Science enabled by new measurements of ocean properties from geostationary orbit (GEO-CAPE, etc)***

**NASA Carbon Cycle and Ecosystems Joint Science Workshop **
**Adelphi, Maryland**
**April 28, 2008**

## Slide 2

## What is the GEO-CAPE Mission?

- geosynchronous Earth orbit near 80°W longitude:
- UV-visible-near-IR **wide-area imaging spectrometer** (7-km nadir pixel) capable of mapping North and South America from 45°S to 50°N at about hourly intervals,
- steerable high-spatial-resolution (250 m) **event-imaging spectrometer** with a 300-km field of view, and
**IR correlation radiometer** for CO mapping over a field consistent with the wide-area spectrometer.

## Questions

** ****What science is enabled by new measurements:**
-  high-temporal-frequency? many views per day
-  high-spatial-resolution? 250 meter at nadir
-  10-nm spectral resolution (UV-NIR)

**Context of two broad scientific goals:**
- to understand how coastal marine ecosystems respond to variability in physical and chemical environment:
- 		forcings >> phytoplankton >> higher tropic levels
- to understand the carbon fluxes between land and coastal ocean, and coastal ocean and deep ocean

## Geostationary: the only satellite-based method to discriminate physical from biological forcing in the surface ocean at frequencies shorter than once per day

**Physical forcings:**
- Tides have a major effect on observed variability:
- 		lateral displacement
- 		vertical mixing and resuspension
- 		sinking (position of tidal fronts)
- Horizontal eddy diffusion processes
**Biological forcings:**
- Diurnal cycles in cell division and fluorescence
- Diurnal cycles in grazing

## Geostationary: high temporal resolution (hourly) enables coherent observations of rates of change

- _Derived variables (pools):_
- POC: 	phytoplankton biomass and detritus
- PIC:  	calcite, inorganic sediment
- DOC:  	region-specific relationship with CDOM
- DIC:  	surface ocean pCO2, carbonate and bicarbonate

## Spatial resolution (250 n) is important..

- Size of phytoplankton patches is related to physical dispersion rates and growth rates in coastal waters ... growth must counteract physical dispersion for patches to exist (e.g. Harmful Algal Bloom patches).
- 250-meter size is ideal -- get info at scale of estuaries and upwelling “hot spots” near coast
- Observations of rainfall, land-cover/land-use changes, and effects on coastal ocean (air and water – including ground water)

## Questions:

- What do we need to do scientifically to use these new measurements and/or to get ready for the mission?

- Examples might include:
-  algorithm development
-  model development
-  coordinated field campaigns
-  sustained coastal ocean observing systems

##    Derived variables (pools): 

-    _Derived variables (pools):_
- POC: 	phytoplankton biomass and detritus
- PIC:  	calcite, inorganic sediment
- DOC:  	region-specific relationship with CDOM
- DIC:  	surface ocean pCO2, carbonate and bicarbonate

- Carbon pools are observed at times t1, t2,  ... throughout the day.

_**Models**_**:**  System of models in which the regional carbon-cycle model is nested within a basin-scale ocean and atmospheric circulation model.  Within the region, carbon cycle model includes the effects of the physical circulation, biology and biogeochemistry.

- Observed rates of change will be modeled:

- dCx/dt = P – L + horizontal + vertical

## Questions:

- Major issues to be resolved ...?

- Major issues include:
-  what in situ coastal observing system is needed for cal/val and to make ancillary measurements?
-  what is the needed spectral resolution?
-  what is needed in S:N?
-  what is needed in ground data system (volume of data, archiving, reprocessing)?
-  who decides what events take priority?