A Comparison of Particulate Organic Carbon (POC) from In

situ and Satellite Ocean Color Data Off the Coast of

Antarctica

Amanda HydeAntonio Mannino (advisor)

Research and Discover Program; 2010

Importance of satellites

Spatial coverage from scientific cruises over 20 years (Gardner et al. 2006)

Spatial cover from SeaWiFS on July 18, 2010

(http://oceancolor.gsfc.nasa.gov 2010)

versus

Measuring POC from satellites

Sea Surface

Top-of-the-Atmosphere

The satellite views the spectral light field at the top-of-the-atmosphere.

Satellite

POC

1. Removes atmosphere from the total signal to derive estimate of light field emanating from sea surface (water-leaving radiance, Lw).

2. Relates remote-sensing reflectance to geophysical product (POC) of interest.

3. Spatially / temporally bin and remap satellite POC observations.

Orbital path of MODIS (NASA Ocean Biology Processing

Group 2008)

Basics of measuring ocean color from an orbiting satellite (NASA Ocean Biology

Processing Group 2008)

Algorithms

POC = 169.7×[Rrs(443)/Rrs(555)]-0.936

(Stramski et al. 2008)

visible light

wavelength (nm)

near-infraredultra-violet

Rrs(λ) = remote-sensing reflectance (units =

sr-1) NASA Ocean Biology Processing Group 2008

Study site

A. Hyde 2010

www.bugbog.com 2010

Sampling stations off the coast of the

Antarctic Peninsula

N

in the lab...

Elementar vario MICRO cube CHN Elemental Analyzer (A. Hyde 2010)

12M HCl acid fuming to remove inorganic carbon

(A. Hyde 2010)

From filter to tablet (A. Hyde 2010)

Processing satellite data

Level 1A ocean color data (available at oceancolor.gsfc.nasa.gov)

Dates used: Feb 21 - Mar 4, 2008

60S - 65S latitude; 50W - 63W longitude

Seadas 6.1.1 used for processing

http://oceancolor.gsfc.nasa.gov 2010

Results

In situ [POC] ranged from 79.0 ug/L to 232.2 ug/L

Satellite derived [POC] ranged from 69.0 ug/L to 155.2 ug/L

A. Hyde 2010

Example of L2 POC data file of March 4, 2008 (A. Hyde 2010)

Statistics

Mean APD% = 16.4%

RMSE = 30.4 ug/L

Percent differences ranged between 4.1% and 33.2%

No significant difference between in situ and satellite derived POC (JMP 8.0, one-way ANOVA, p > 0.05)

R2 = 0.89slope = 0.52RMSE = 30.4N = 11

need for further satellite validation

SOS cruise lasted 13 days; 2 days of satellite ocean color data were usable

85 stations included; only 11 had correlating satellite ocean color data

Data containing clouds, ice, sun glint, high radiance, stray light, high viewing zenith angle, and high solar zenith angle were all excluded

On average, only 15% of satellite data are usable (Bailey and Werdell 2006)

www.tpwd.state.tx.us 2010

Thanks to...

UNH-NASA Research and Discover Program

Antonio Mannino - advisor

Mike Novak - lab help

Sean Bailey - Seadas 6.1.1 help

www.eos.unh.edu 2010www.nasa.gov 2010

Questions...

http://blog.1choice4yourstore.com 2010

Literature cited

Anon. 2008. “Protocol for vario MICRO cube Elemental Analyzer” handout from A. Mannino. 14 Jun 2010.

Bailey, S. W. and P. J. Werdell. 2006. A multi-sensor approach for the on-orbit validation of ocean color satellite data products. Remote Sensing of Environment 102: 12-23.

Gardner, W. D., A. V. Mishonov, and M. J. Richardson. 2006. Global POC concentrations from in-situ and satellite data. Deep-Sea Research II 53: 718-740.

Mannino, A., M. E. Russ, and S. B. Hooker. 2008. Algorithm development and validation for satellite-derived distributions of DOC and CDOM in the U.S. Middle Atlantic Bight. Journal of Geophysical Reserach 113

Stramski, D., R. A. Reynolds, M. Babin, S. Kaczmarek, M. R., Lewis, R. Röttgers, A. Sciandra, M. Stramska, M. S. Twardowski, B. A. Franz, and H. Claustre. 2008. Relationships between the surface concentration of particulate organic carbon and optical properties in the eastern South Pacific and eastern Atlantic Ocean. Biogeosciences 5: 171-201.

Image CitationsAnon. 2010. Antarctica Circle Map. http://www.bugbog.com/images/maps/antarctic-circle_map.jpg (22 Jul 2010)

Anon. 2010. home page www.nasa.gov (22 Jul 2010)

Anon. 2010. Sunday, 18 Jul 2010 (2010199). http://oceancolor.gsfc.nasa.gov/cgi/pcac9000.pl?day=2010199W (13 Jul 2010)

Anon. 2010. untitled. http://oceancolor.gsfc.nasa.gov/cgi/l3/A20080572008064.L3m_8D_POC_poc_4km.png?sub=img (13 Jul 2010)

Anon. 2010. Research and Discover. http://www.eos.unh.edu/researchanddiscover/interns.shtml (29 Jul 2010)

Fennell, S. 2010. Do you have questions about your online store? #ecommerce. http://blog.1choice4yourstore.com/2010_03_01_archive.html (21 Jul 2010)

Gardner, W. D., A. V. Mishonov, and M. J. Richardson. 2006. Global POC concentrations from in-situ and satellite data. Deep-Sea Research II 53: 718-740.

Hyde, A. 2010. Personal photos.

Loeffler, C. 2004. The state of wonder: what’s all this fuss about water? http://www.tpwd.state.tx.us/learning/webcasts/connections04/water.phtml (23 Jul 2010)

NASA Ocean Biology Processing Group. 2008. Satellite observations of ocean color. SeaDAS Training Material; Goddard Space Flight Center, Greenbelt, Maryland.