Sentinel 1 data for my study area has a revisit period of 12 days, why?

Hello everyone

My study area has only images from Sentinel-1A and a temporal resolution of 12 days.

Please help, I cant find data at 6 days interval

Acquisition segment

It is not available over your area. S-1 is an European constellation that does not have enough satellite resources to image all land-masses every 6 days, but imaging frequency is decided based on priorities.

https://sentinel.esa.int/web/sentinel/missions/sentinel-1/observation-scenario

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Hey Wonga

Some points from my experience with data in South Africa.

  • We are relatively far away from the Poles so that means we get less frequent coverage than say Europe from one Satellite. Most rapid is 12 days.
  • Sentinel-1 is a constellation of two satellites, theoretically that means you could get 6 days revisit for your area, however, historically over South Africa we only get 1 satellite’s acquisition. This is due to the limited data, power and bandwidth available for acquisitions.
  • Sentinel-1a seems to be doing South Africa, 1b would then cover Botswana/Zambia 1a would then do the next bit north and so on.
  • Reliable 12 day repeats really only started in the beginning of 2017 after Sentinel-b was launched, before that 1a had to do all the work and we often only got repeats of 24 days with some periods of even less.
  • 1a data is ascending over SA
  • There have been a few Sentinel-1b acquisitions which give descending data but these seem to focus on events or areas like Gauteng.

I am curious about your application of Sentinel-1 data to Mthatha. I guess it is urban, vegetation or land degradation related work?

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Hi Andre,

I am trying to fuse SAR and optical data to monitor small-scale crop fields. I had already fused them for cropland imapping

Are you also using S-1, and what for?