The MCD19A2 V6 data product is a MODIS Terra and Aqua combined Multi-angle Implementation of Atmospheric Correction (MAIAC) Land Aerosol Optical Depth (AOD) gridded Level 2 product produced daily at 1 km resolution. For more information see the MAIAC user guide.

Documentation:

• User's Guide

• Algorithm Theoretical Basis Document (ATBD)

• General Documentationhttps://ladsweb.modaps.eosdis.nasa.gov/filespec/MODIS/6/MCD19A2

MCD19A2 V6数据产品是MODIS Terra和Aqua结合的大气校正多角度实施（MAIAC）陆地气溶胶光学深度（AOD）网格化2级产品，每天以1公里分辨率制作。更多信息见MAIAC用户指南。

文件。

用户指南

算法理论基础文件(ATBD)

一般文件

Dataset Availability

2000-02-01T00:00:00 - 2021-09-19T00:00:00

Dataset Provider

NASA LP DAAC at the USGS EROS Center

Collection Snippet

ee.ImageCollection("MODIS/006/MCD19A2_GRANULES")

Resolution

1000 meters

Bands Table

Name	Description	Min	Max	Units	Scale
Optical_Depth_047	Blue band (0.47 μm) aerosol optical depth over land	-100	5000		0.001
Optical_Depth_055	Green band (0.55 μm) aerosol optical depth over land	-100	5000		0.001
AOD_Uncertainty	AOD uncertainty based on blue-band surface brightness (reflectance)	-100	30000		0.0001
FineModeFraction	Fine mode fraction for ocean	0	10000		0.0001
Column_WV	Column water vapor over land	0	30000	cm	0.001
AOD_QA	AOD QA				0
AOD_QA Bitmask	Bits 0-2: Cloud mask 0: Undefined 1: Clear 2: Possibly cloudy (detected by AOD filter) 3: Cloudy (detected by cloud mask algorithm) 5: Cloud shadow 6: Hot spot of fire 7: Water sediments Bits 3-4: Land water snow/ice mask 0: Land 1: Water 2: Snow 3: Ice Bits 5-7: Adjacency mask 0: Normal condition/Clear 1: Adjacent to clouds 2: Surrounded by more than 8 cloudy pixels 3: Adjacent to a single cloudy pixel 4: Adjacent to snow 5: Snow was previously detected in this pixel Bits 8-11: QA for AOD 0: Best quality 1: Water Sediments are detected (water) 3: There is 1 neighbor cloud 4: There is >1 neighbor clouds 5: No retrieval (cloudy, or whatever) 6: No retrievals near detected or previously detected snow 7: Climatology AOD - altitude above 3.5km (water) and 4.2km (land) 8: No retrieval due to sun glint (water) 9: Retrieved AOD is very low (<0.05) due to glint (water) 10: AOD within +-2km from the coastline (may be unreliable) 11: Land, research quality - AOD retrieved but CM is possibly cloudy Bit 12: Glint mask 0: No glint 1: Glint (glint angle < 40°) Bits 13-14: Aerosol model 0: Background model (regional) 1: Smoke model (regional) 2: Dust model Bit 15: Reserved 0: Reserved for future use 1: Reserved for future use
AOD_MODEL	AOD model used in retrieval	0	100		0
Injection_Height	Smoke injection height	0	10000	m	0
cosSZA	Cosine of solar zenith angle (5 km resolution)	0	10000		0.0001
cosVZA	Cosine view zenith angle (5 km resolution)	0	10000		0.0001
RelAZ	Relative azimuth angle (5 km resolution)	-18000	18000		0.01
Scattering_Angle	Scattering angle (5 km resolution)	-18000	18000		0.01
Glint_Angle	Glint angle (5 km resolution)	-18000	18000		0.01

 使用说明：

MODIS data and products acquired through the LP DAAC have no restrictions on subsequent use, sale, or redistribution.

通过LP DAAC获得的MODIS数据和产品对后续使用、销售或再分配没有限制。

引用：

LP DAAC - MCD12Q1LP DAAC - Land Processes Distributed Active Archive Center - Sioux Falls, SDhttps://doi.org/10.5067/MODIS/MCD12Q1.006

代码：

var collection = ee.ImageCollection('MODIS/006/MCD19A2_GRANULES')
                  .select('Optical_Depth_047')
                  .filterDate('2019-01-01', '2019-01-15');

var band_viz = {
  min: 0,
  max: 500,
  palette: ['black', 'blue', 'purple', 'cyan', 'green', 'yellow', 'red']
};

Map.addLayer(collection.mean(), band_viz, 'Optical Depth 047');
Map.setCenter(76, 13, 6);