Q: My data values are much larger than I was expecting. What units are the data in?

A:

For data processed in 2011 and earlier, the level 1 data are supplied as calibrated at-sensor (ie not atmospherically corrected) radiance in units of uW/cm2/sr/nm (microwatts per centimetre-squared per steradian per nanometre). They are also multiplied by 1000 in the delivered files to avoid problems with floating-point arithmetic and storage.

For data processed in 2012 onwards the level 1 data are supplied as calibrated at-sensor radiance in units of nW/cm2/sr/nm. Please note that data values have not changed between 2012 and previous data, only that the scalar of 1000 has been brought into the units.

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