Since it's a daily product, I think it should be the same as "START" with 23:59:59 time.
[Q] VJ243MA4 CMR "End" Record Error?
[Q] VJ243MA4 CMR "End" Record Error?
Hi, I noticed that each granule has the "END" date that is "START" + 7.
Since it's a daily product, I think it should be the same as "START" with 23:59:59 time.
Please compare the VNP09GA product CMR record, which looks correct.
Since it's a daily product, I think it should be the same as "START" with 23:59:59 time.
Please compare the VNP09GA product CMR record, which looks correct.
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Re: [Q] VJ243MA4 CMR "End" Record Error?
Hello,
The temporal formatting of the BRDF/Albedo products are different than any other MODIS/VIIRS product. They are all 16-day products that are produced every day. Each cover a 16-day period. What primary difference about the BRDF/Albedo products then other multi day products is that the Acquisition date given is the 9th day of that 16 day period and consequently the pixel value of that product is processed so the 9th day of the period carries more weight for the overall value. So from the 9th day there are 7 more days of acquisitions used in the pixel values. The End date is actually accurate, but an argument could be made the Start date should actually be 8 days earlier. When a search is performed in the CMR it searches the metadata for the acquisition date as the first day and then it also locates and uses the final date as its End date. All other MODIS/VIIRS multi day products use the first day of the period as the acquisition date as one would expect. Please let us know if you have any questions.
Thanks,
Brett
The temporal formatting of the BRDF/Albedo products are different than any other MODIS/VIIRS product. They are all 16-day products that are produced every day. Each cover a 16-day period. What primary difference about the BRDF/Albedo products then other multi day products is that the Acquisition date given is the 9th day of that 16 day period and consequently the pixel value of that product is processed so the 9th day of the period carries more weight for the overall value. So from the 9th day there are 7 more days of acquisitions used in the pixel values. The End date is actually accurate, but an argument could be made the Start date should actually be 8 days earlier. When a search is performed in the CMR it searches the metadata for the acquisition date as the first day and then it also locates and uses the final date as its End date. All other MODIS/VIIRS multi day products use the first day of the period as the acquisition date as one would expect. Please let us know if you have any questions.
Thanks,
Brett
Re: [Q] VJ243MA4 CMR "End" Record Error?
Thank you for the explanation about 16-days!
Yes, I think START DATE should be 9 days earlier to be consistent.
How about adding PEAK (or ACQUISITION) DATE to CMR for this kind of product
so that users can search granule more precisely?
Yes, I think START DATE should be 9 days earlier to be consistent.
How about adding PEAK (or ACQUISITION) DATE to CMR for this kind of product
so that users can search granule more precisely?