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LP DAAC Data Access through OPeNDAP and Web Services. LP DAAC Data Access. Data Pool and MODIS ~ 1500 terabytes (compressed) Including Collection 6 (partial) Request granules via URL http://e4ftl01.cr.usgs.gov/MOLT/MOD09Q1.005/2015.01.09/MOD09Q1.A2015009.h11v04.005.2015027222534.hdf
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LP DAAC Data Access • Data Pool and MODIS • ~1500 terabytes (compressed) • Including Collection 6 (partial) • Request granules via URL http://e4ftl01.cr.usgs.gov/MOLT/MOD09Q1.005/2015.01.09/MOD09Q1.A2015009.h11v04.005.2015027222534.hdf • Single granule downloaded locally • Full Spatial extent • All associated bands • Single day/composite period
OPeNDAP Data Access • Access and extract discrete subsets • Spatial • Band/Layers • Temporal • Request data via URL http://opendap.cr.usgs.gov/opendap/hyrax/MOD09Q1.005/h11v04.ncml.ascii?sur_refl_b01[683:1:683][2000:1:2010][2000:1:2010] • Returns data that the user intends to use! • Reduces time spent downloading and processing • Minimizes the amount of data downloaded
OPeNDAP Data Access OPeNDAP request: http://opendap.cr.usgs.gov/opendap/hyrax/MOD09Q1.005/h11v04.ncml.ascii?sur_refl_b01[683:1:683][2000:1:2010][2000:1:2010] Return: Dataset: h11v04.ncml sur_refl_b01[0][0], 0.5359, 0.5657, 0.5258, 0.4739, 0.4648, 0.5087, 0.5234, 0.5234, 0.6214, 0.5793, 0.5374 sur_refl_b01[0][1], 0.5759, 0.5414, 0.5338, 0.4489, 0.432, 0.5036, 0.6051, 0.6214, 0.5793, 0.455, 0.446 sur_refl_b01[0][2], 0.4594, 0.5409, 0.6224, 0.6289, 0.6289, 0.6051, 0.5005, 0.5005, 0.3325, 0.3092, 0.3826 sur_refl_b01[0][3], 0.5831, 0.5831, 0.6126, 0.6307, 0.6307, 0.5277, 0.612, 0.3325, 0.3092, 0.332, 0.4036 sur_refl_b01[0][4], 0.6329, 0.6126, 0.6061, 0.5691, 0.5691, 0.612, 0.5841, 0.5841, 0.4301, 0.4782, 0.6271 sur_refl_b01[0][5], 0.6092, 0.6092, 0.6152, 0.5691, 0.6297, 0.6035, 0.5052, 0.5052, 0.4782, 0.6518, 0.6913 sur_refl_b01[0][6], 0.5712, 0.6152, 0.6248, 0.5686, 0.5686, 0.3522, 0.5088, 0.5912, 0.6316, 0.4729, 0.5756 sur_refl_b01[0][7], 0.5737, 0.5737, 0.524, 0.5368, 0.3522, 0.5691, 0.5944, 0.4085, 0.4729, 0.5375, 0.5375 sur_refl_b01[0][8], 0.5606, 0.5211, 0.5368, 0.5874, 0.5874, 0.343, 0.26, 0.26, 0.3825, 0.5794, 0.5863 sur_refl_b01[0][9], 0.5883, 0.5591, 0.5263, 0.4325, 0.343, 0.4485, 0.626, 0.626, 0.5462, 0.3682, 0.3463 sur_refl_b01[0][10], 0.5435, 0.5263, 0.4325, 0.4887, 0.4887, 0.5175, 0.626, 0.5475, 0.4101, 0.4592, 0.4203
OPeNDAP Data Access • OPeNDAP URLs are complex • Need to know: • Syntax • Product name • Layer name • Time • Geolocation • Tile locations (H & V) • Pixel location (Ydim & Xdim) http://opendap.cr.usgs.gov/opendap/hyrax/MOD09Q1.005/h11v04.ncml.ascii?sur_refl_b01[683:1:683][2000:1:2010][2000:1:2010]
Implementation Architecture Connects
AppEEARS • Application for Extracting and Exploring Analysis Ready Samples • Web application interface for accessing and extracting LP DAAC’s tiled MODIS data
AppEEARS • Built on top of services and tools • Capabilities • Easy access and selection of MODIS product land • Extracts pixel values for sample point locations • Data exploration and interaction • Dynamic Graphs • Tables • Download Bundle • Analysis-ready data
DEMO https://lpdaacsvc.cr.usgs.gov/appeears/