Selecting Dates

The west coast of tasmania is often cloudy.

Finding dates with little cloud cover was necessary.

MODIS Chlorophyl

Using knowledge about upwelling and the low resolution data available here I was able to select 2 dates approximately 6 months apart.

Once I selected a date, I downloaded the A200xxxxxxxxxxx.L2_LAC_OC.bz2. This has all the band I am interested and a bit more.

Now I need to investigate

• if and how the atomsphere has been accounted for.
• reporjection

I have chosen to use MODIS (Moderate Resolution Imaging Spectroradiometer) Aqua Data

http://modis.gsfc.nasa.gov/

Why

• Publicly available
• Temporal and Spatial resolution
• Sensor bands appropriate for ocean colour
• Range of algorithms

MODIS  Band Summary

8	405–420	1000m	Ocean Color/ Phytoplankton/ Biogeochemistry
9	438–448	1000m
10	483–493	1000m
11	526–536	1000m
12	546–556	1000m
13	662–672	1000m
14	673–683	1000m
15	743–753	1000m
16	862–877	1000m

I have reviewed some algorithms for chlorophyl, the following 7 bands were utilised, and I will need to download the data.

9	438–448	B
10	483–493	B
11	526–536	G
12	546–556	G. Mention of re-centring, not certain how this will effect me
13	662–672	R
14	673–683	R aligned with Band 13. Further research required to understand
15	743–753	NIR

Band 13 /Band 14 

Installing QGIS 1.8.0-2 on Mountain Loin

Recently rebuilt my macbook pro,. Today I am installing QGIS . This is how I installed it. Perhaps there are better ways.

QGIS Mac OSX

Sites I referenced

Eospansite Installing qgis 1.6on macosx 
(Version 20130108)
Eospansite Installing gdal on macosx


QGIS installation requires the command line. It and it's dependencies are not packaged up in a single dmg.

Download from kyngchaos

• QGIS-1.8.0-2.dmg
• Dependencies
• GDAL_Complete-1.9.dmg
• GSL_Framework-1.15-2.dmg
• Optional
• GRASS-6.4.2-5-Snow.dmg
• dependencies
• FreeType_Framework-2.4.10-1.dmg
• PIL-1.1.7-4.dmg
• cairo_Framework-1.12.2-1.dmg
• R-2.15.3.pkg (local mirror)

Install order

• GDAL Complete
• Both gdal.pkg and numpy.pkg
• GSL Framework
• FreeType Framework
• Cairo Framework
• PIL
• R
• GRASS
• GRASS and GRASS GDAL plugin
• QGIS

A chapter in this book was referenced by a paper I read. 

It is a good intro to different chlorophyl algorithms (Sometimes call products)

It is in the Unimelb ERC library

Advances in environmental remote sensing : sensors, algorithms, and applications

edited by Qihao Weng.

628.0284 ADVA

I am entering my final semester of a a Master's program.

The main component is a 6 month research project.

Marine phytoplankton are the base of the marine food web and play a key role in the ocean carbon cycle.  These single cell plants found in the upper layers of the global oceans.
The main factors affecting phytoplankton growth are sunlight, water movement, temperature and nutrients. Phytoplankton, in turn impacts all marine trophic levels, atmosphere carbon levels and ocean acidity. Monitoring and quantifying phytoplankton assists scientists in understand, and model, marine ecosystems and climate change.

The scale of the oceans, means in-situ monitoring, with the temporal and spatially density required for statistically significance is not feasible. Satellite remote sensing can provide this level coverage, a number of ocean colour sensors, such as MODIS, MERIS, and SeaWiFS have been deployed.

Chlorophyl, is a suitable measurement indicator of the amount of phytoplankton, in the ocean. Algorithms which model chlorophyl level in open water (Class 1) from ocean color sensor are have been established. These algorithms do not perform well in optical complex water and coastal water. Optically complex water contains active sediment and nutrients components, which contribute to response in the same wavelength range as the chlorophyl, utilise in the open water algorithms.