Composite SST images Marine and Atmospheric Research Remote Sensing Facility

Composite Sea-surface Temperature Images
"Seeing through the clouds"

We can produce cloud-free images of Sea Surface Temperature by combining the data from several satellite passes.

Features

• You can have 'cloud-free' composite images produced automatically for your Personalised SST Web Page.
• These images will be updated daily, and are in addition to the individual images from single satellite passes.
• You can choose from 1, 3, 6, 10, 15 and 20-day composites. The default is for 1, 3 and 6 day composites to be produced.
• This service is an optional extra to the standard Personalised SST Web Page
• Nominal resolution is 3 kilometers.

Background

The infra-red radiation used to detect Sea Surface Temperature from satellites is not capable of penetrating layers of cloud. For this reason, SST images produced from a single satellite pass can easily have areas that are obscured by cloud.

At CSIRO Division of Marine Research, Remote Sensing Facility, we have developed a method for producing images which are 'cloud free'.

We achieve this by sampling several single-pass images. We gather the best non-cloud data from each image to create a 'smoothed' or 'composited' image.

The algorithm we use has some intelligence to minimise the cloud contamination often seen near the edge of clouds.

The result ..

Compare the following images, produced on the same day.

6 day composite

single pass

Note

1. As the composite period increases the chance of obtaining a cloud-free view increases but at the same time the finer scale features become more blurred and more uncertain in position .

2. All of the single pass images that go into making the composites would normally appear on your on-line SST pages, in addition to the composites, since the single-pass images are part of the default service.


Products and Services: Personalised SST Web Page