Sentinel-2 data introduction and download

1 Sentinel-2 brief introduction

SENTINEL-2 is a European wide-swath, high-resolution, multi-spectral imaging mission.

Sentinel-2 It is a high-resolution multispectral imaging satellite , The revisit cycle of a satellite is 10 God , Two complementary , The revisit cycle is 5 God . It is divided into 2A and 2B Two satellites .2A On 2015 year 6 month 23 Japan 01:52 UTC With “ Vega ” Launch the launch vehicle .2B On 2017 year 3 month 07 Day Beijing time 9 when 49 branch UTC With “ Vega ” Launch the launch vehicle . After both enter the operation state at the same time , Every time 5 One complete imaging of the equatorial region of the earth can be completed in one day , For higher latitudes , This cycle only needs 3 God .

Every SENTINEL-2 Satellite weight reduction 1.2 Tons of . The life of the satellite is 7.25 year , These include 3 Months of on orbit commissioning . The battery and propellant on it can adapt to 12 Operating requirements for the year , Including end of life orbital flight operations .

Two identical SENTINEL-2 The satellite is in the sun synchronous orbit with 180 km The phases of are synchronized with each other , The average height is 786 km. Every SENTINEL-2 The position of the satellite in its orbit is determined by the dual frequency global navigation satellite system （GNSS） Measured by the receiver .

Sentinel-2 The satellite carries a multispectral instrument (MSI), covering 13 A spectral band , The ground resolution is 10m、20m and 60m：

Sensor	Band number	Band name	Sentinel-2A		Sentinel-2B		Resolution (meters)
			Central wavelength (nm)	Bandwidth (nm)	Central wavelength (nm)	Bandwidth (nm)
MSI	1	Coastal aerosol	443.9	20	442.3	20	60
MSI	2	Blue	496.6	65	492.1	65	10
MSI	3	Green	560.0	35	559	35	10
MSI	4	Red	664.5	30	665	30	10
MSI	5	Vegetation Red Edge	703.9	15	703.8	15	20
MSI	6	Vegetation Red Edge	740.2	15	739.1	15	20
MSI	7	Vegetation Red Edge	782.5	20	779.7	20	20
MSI	8	NIR	835.1	115	833	115	10
MSI	8b	Narrow NIR	864.8	20	864	20	20
MSI	9	Water vapour	945.0	20	943.2	20	60
MSI	10	SWIR – Cirrus	1373.5	30	1376.9	30	60
MSI	11	SWIR	1613.7	90	1610.4	90	20
MSI	12	SWIR	2202.4	180	2185.7	180	20

       

2 Data introduction and download

Types of data products that can be downloaded ：

Name	High-level Description	Production & Distribution	Data Volume
Level-1C	Top-of-atmosphere reflectances in cartographic geometry	Systematic generation and on-line distribution	600 MB (each 100x100 km2)
Level-2A	Bottom-of-atmosphere reflectance in cartographic geometry	Systematic generation and on-line distribution and generation on user side (using Sentinel-2 Toolbox)	800 MB (each 100x100 km2)

The product is a combination of fixed size basic tiles . Tiles are products （ Contains all spectral bands ） The smallest indivisible partition of . about Level-1C and Level-2A, Block is UTM / WGS84 Under projection 100x100 km2 Orthophoto Image . 

UTM（ Universal horizontal axis Mercator ） The projection system divides the earth's surface into 60 Regions , The vertical width of each area is longitude 6°, The horizontal width is latitude 8°.

   

Level-1C  It is a product of atmospheric apparent reflectance corrected by orthophoto correction and geometric precision correction , No atmospheric correction .

Level-2A  It mainly contains atmospheric corrected bottom layer reflectance data （Bottom-of-Atmosphere corrected reflectance）, But this L2A Data needs to be produced by users according to their needs , So ,ESA Special production has been released L2A Level data plug-in Sen2cor.

download ：

1 Open Access Hub  Download from the official website , Need to register first

Advanced search ：

After selecting the fixed polygon area , Click the search button directly , You can filter out the images within the required range ：

Or by IDM Downloader , from EarthExplorer  download

The USGS Sentinel-2 Archives are ESA A portion of all available data represents .  This data compares to ESA There is a certain delay in the data published on the official website .

3 Preprocessing

It's mainly about Level-1C Radiometric calibration and atmospheric correction are carried out for grade I products .

The processing software includes :

Sen2cor download     Treatment process

Data source reference ： Geographic remote sensing ecological network www.gisrs.cn

meanwhile , Geographic remote sensing ecological network www.gisrs.cn Many scientific data in the field of Geographical remote sensing are shared on the website （ Land use data 、npp Net primary productivity data 、NDVI data 、 Weather data （ rainfall 、 The temperature 、 Evapotranspiration 、 radiation 、 humidity 、 Sunshine hours 、 The wind speed 、 Vapor pressure data ）、 Runoff data 、 Night light data 、 Statistical yearbook 、 road network 、POI Point of interest data 、GDP Distribution 、 Population density distribution 、 Vector boundary of tertiary watershed 、 Geological hazard distribution data 、 Soil type 、 Soil texture 、 Soil organic matter 、 soil PH value 、 Soil texture 、 Soil erosion 、 Vegetation type 、 Distribution of nature reserves 、 Building contour distribution and other geographic data , And about the gis、 A tutorial on remote sensing ）.