Hi, Sir
Hope everything is fine
1. Recently, I try to match MCD19A2 with MOD03, but the MCD19A2 data without geolocation information, both are 1-km spatial resolution. I don't know how to deal with this problem.
2. I attempted to extract the AOD_550nm in MCD19A2 for the known latitude and longitude sites. But MCD19A2 data without geolocation information. Meanwhile, I know that each pixel of MOD021KM corresponds to that of MOD03, but I subsequently want to match MCD19A2 with MOD021KM. these data all are 1-km spatial resolution, But, I don't know how the MCD19A2 data match with MOD03. So, could you please help me give some suggestions.
3. In process the MCD19A2 data, I want to know which layer corresponds to Terra or Aqua so that I can match the MCD19A2 with MOD or MYD.
Best wishes
MCD19A2 data process
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Re: MCD19A2 data process
Hi,
Sorry for the frustrations with working with the data. Unfortunately, the MCD19A2 Gridded data and the MOD03 are not compatible at all. The MOD03 are used to georectify other swath data which is then used upstream in the production of the MODIS Level 2G, Level 3 and Level 4 MODIS gridded products. The upper-level gridded products such as the MCD19 products are all projected into the Sinusoidal projection and made into 10 x10 degree tiles where the pixel size is uniform throughout the entire tile. The MOD03 is not projected, so they would not match up, except at nadir.
The MCD19 is in the Sinusoidal projection, but many software packages have issues recognizing the projection in the HDF format Also the MCD19 is 3 dimensional with all the corresponding acquisitions packed in each SDS layer. According to the User Guide: "Each daily file (MCD19A1 and A2) usually contains multiple orbit overpasses (1-2 at equator and up to 30 in polar regions for combined Terra and Aqua) which represents the third (time) dimension of MAIAC daily files. The orbit number and the overpass time of each orbit are saved in global
attributes “Orbit_amount” and “Orbit_time_stamp” sequentially. The Orbit_time_stamp is in the format of “YYYYDDDHHMM[TA]”, where YYYY is year, DDD is Julian day, HH is hour MM is minute, T stands for Terra and A stands for Aqua. At high latitudes, only first 16 orbits with
largest coverage are selected for processing per day in order to limit the file size."
What software package do you have available, we may be able to help you find the geolocation information for the data you have?
Thanks,
Brett
Sorry for the frustrations with working with the data. Unfortunately, the MCD19A2 Gridded data and the MOD03 are not compatible at all. The MOD03 are used to georectify other swath data which is then used upstream in the production of the MODIS Level 2G, Level 3 and Level 4 MODIS gridded products. The upper-level gridded products such as the MCD19 products are all projected into the Sinusoidal projection and made into 10 x10 degree tiles where the pixel size is uniform throughout the entire tile. The MOD03 is not projected, so they would not match up, except at nadir.
The MCD19 is in the Sinusoidal projection, but many software packages have issues recognizing the projection in the HDF format Also the MCD19 is 3 dimensional with all the corresponding acquisitions packed in each SDS layer. According to the User Guide: "Each daily file (MCD19A1 and A2) usually contains multiple orbit overpasses (1-2 at equator and up to 30 in polar regions for combined Terra and Aqua) which represents the third (time) dimension of MAIAC daily files. The orbit number and the overpass time of each orbit are saved in global
attributes “Orbit_amount” and “Orbit_time_stamp” sequentially. The Orbit_time_stamp is in the format of “YYYYDDDHHMM[TA]”, where YYYY is year, DDD is Julian day, HH is hour MM is minute, T stands for Terra and A stands for Aqua. At high latitudes, only first 16 orbits with
largest coverage are selected for processing per day in order to limit the file size."
What software package do you have available, we may be able to help you find the geolocation information for the data you have?
Thanks,
Brett