Satellite Remote Sensing of the Oceans

Presented here is an overview of the kind of remote sensing that is done at Southampton University and how Linux has helped improve our productivity.

As I have mentioned, IDL is our favorite package for dealing with satellite images even though many are available. Most tend to be inflexible and tailor-made for doing specific types of image analysis. IDL can do most of the same operations more cheaply and flexibly while allowing you to interact with the data and merge data from several sources. However, IDL is a programming language in its own right, so there is a learning curve inherent to using it.

The choice of other system components is not as critical as choosing the video card, motherboard, processor and monitor. When it comes to backing up our data, an Exabyte drive suits us nicely for backing up anything less than 5GB in size.

Further Points

Again, IDL is the main processing software for this type of work. Many users feel they are comfortable using LaTeX under Linux too, although this appears to be a point of contention. Most of us are still locked into using MS Word for want of a cheap Linux word processor that is Word compatible and can handle multiple data formats and equations. We are now looking at some alternatives like Applixware.

Linux has reduced the computing cost of the Oceanography Department's satellite remote sensing group in terms of both time and money. Its stability has been its greatest asset in converting die-hard Windows fanatics into potential Linux gurus. For many of us Linux has enabled us to embark on a voyage of discovery into the computing world. We now have a deeper understanding of how our PCs work as Linux has brought us closer to the machine. We are currently reviewing the hardware and software requirements of the group for the next couple of years. We plan to continue using Linux well into the next millennium and are quite happy with the decision.


The SAR images in this article were obtained free from the European Space Agency.

Simon Keogh ( is a graduate in Astrophysics from the University of Leeds and is now a NERC-sponsored Ph.D. student at the University of Southampton studying the oceanic thermal skin. In his spare time he enjoys golf, soccer and travelling.

Emmanouil Oikonomou ( Emmanouil Oikonomou is a Greek Ph.D. student studying SAR imaging and fluid dynamics. He spends his spare time directing and scripting short movies for fun.

Daniel Ballestero ( is a Costa Rican Ph.D. student studying ocean colour.

Dr. Ian Robinson ( is the Head of the Oceanography Department's satellite remote sensing group, and his interests on the subject vary from SAR to Altimetry, Ocean Colour, Thermal Imagery and general remote sensing.