Sentinel-5P NRTI NO2: Near Real-Time Nitrogen Dioxide Data (COPERNICUS/S5P/NRTI/L3_NO2)
###Sentinel-5 Precursor
Sentinel-5 Precursor is a satellite launched on 13 October 2017
by the European Space Agency to monitor air pollution. The onboard sensor
is frequently referred to as Tropomi (TROPOspheric Monitoring Instrument).
All of the S5P datasets have two versions: Near Real-Time (NRTI) and Offline
(OFFL). The NRTI assets cover a smaller area than the OFFL assets, but
appear more quickly after acquisition. The OFFL assets contain data
from a single orbit (which, due to half the earth being dark, contains
data only for a single hemisphere).
The original Sentinel 5P Level 2 (L2) data is binned
by time, not by latitude/longitude. To make it possible to ingest the data
into Earth Engine, each Sentinel 5P L2 product is converted to L3, keeping
a single grid per orbit (that is, no aggregation across products
is performed).
Source products spanning the antimeridian are ingested as two Earth Engine
assets, with suffixes _1 and _2.
The conversion to L3 is done by the harpconvert
tool using the bin_spatial operation. The source data is filtered to
remove any values with QA values of less than 50.
###NRTI/L3_NO2
This dataset provides near real-time high-resolution imagery of NO2 concentrations.
To make our NRTI L3 products, we use harpconvert
to grid the data.
Example harpconvert invocation for one tile:
harpconvert --format hdf5 --hdf5-compression 9
-a 'tropospheric_NO2_column_number_density_validity>50;derive(datetime_stop {time});
bin_spatial(2001, 50.000000, 0.01, 2001, -120.000000, 0.01);
keep(NO2_column_number_density,tropospheric_NO2_column_number_density,
stratospheric_NO2_column_number_density,NO2_slant_column_number_density,
tropopause_pressure,absorbing_aerosol_index,cloud_fraction,
sensor_altitude,sensor_azimuth_angle,
sensor_zenith_angle,solar_azimuth_angle,solar_zenith_angle)'
S5P_NRTI_L2__NO2____20181107T013042_20181107T013542_05529_01_010200_20181107T021824.nc
output.h5
| Name | Description | Gee:unit |
|---|---|---|
| NO2_column_number_density | Total vertical column of NO2 (ratio of the slant column density of NO2 and the total air mass factor). | mol/m^2 |
| tropospheric_NO2_column_number_density | tropospheric vertical column of NO2 | mol/m^2 |
| stratospheric_NO2_column_number_density | stratospheric vertical column of NO2 | mol/m^2 |
| NO2_slant_column_number_density | NO2 slant column density | mol/m^2 |
| tropopause_pressure | topopause pressure | Pa |
| absorbing_aerosol_index | Aerosol index (at wavelengths 354/388, i.e. the OMI pair) from the AER_AI level 2 product. See [Level 2 Algorithms - Aerosol Index](https://earth.esa.int/web/sentinel/technical-guides/sentinel-5p/level-2/aerosol-index). | Dimensionless |
| cloud_fraction | Effective cloud fraction. See the [Sentinel 5P L2 Input/Output Data Definition Spec](https://sentinels.copernicus.eu/documents/247904/3119978/Sentinel-5P-Level-2-Input-Output-Data-Definition), p.220. | fraction |
| sensor_altitude | Altitude of the satellite with respect to the geodetic sub-satellite point (WGS84). | m |
| sensor_azimuth_angle | Azimuth angle of the satellite at the ground pixel location (WGS84); angle measured East-of-North. | degrees |
| sensor_zenith_angle | Zenith angle of the satellite at the ground pixel location (WGS84); angle measured away from the vertical. | degrees |
| solar_azimuth_angle | Azimuth angle of the Sun at the ground pixel location (WGS84); angle measured East-of-North. | degrees |
| solar_zenith_angle | Zenith angle of the satellite at the ground pixel location (WGS84); angle measured away from the vertical. | degrees |
Providers | |
|---|---|
| European Union/ESA/Copernicus (producer, licensor) | |
| Google Earth Engine (host) | |
| STAC Version | 0.6.2 |
| Keywords | TROPOMI, air_quality, copernicus, esa, eu, knmi, nitrogen_dioxide, no2, pollution, s5p, sentinel |
| License | proprietary |
| Temporal Extent | 7/10/2018, 3:05:44 AM - now |
| Type | image_collection |
| GSD | arc degreesm |
| Platform | Sentinel-5P |
| Instrument | TROPOMI |
| cube:dimensions | {"x":{"type":"spatial","axis":"x","extent":[-180,180]},"y":{"type":"spatial","axis":"y","extent":[-90,90]},"temporal":{"type":"temporal","extent":["2018-07-10T10:05:44Z",null]},"bands":{"type":"bands","values":["NO2_column_number_density","tropospheric_NO2_column_number_density","stratospheric_NO2_column_number_density","NO2_slant_column_number_density","tropopause_pressure","absorbing_aerosol_index","cloud_fraction","sensor_altitude","sensor_azimuth_angle","sensor_zenith_angle","solar_azimuth_angle","solar_zenith_angle"]}} |