Table of Contents

Overview

Sentinel-1 is a pair of European c-band radar imaging (SAR) satellites. Sentinel-1A launched in 2014 and Sentinel-2 launched in 2016. Sentinel-1 operates day and night on a six day revisit cycle. The ability to observe through clouds means it can collect imagery in bad weather. Sentinel-1 data is useful for sea and land monitoring, emergency response due to environmental disasters, and economic applications.

The Sentinel-1 dataset available on GBDX is the Registry of Open Data on AWS.

Quickstart Examples

In these examples, SENTINEL1 is the value for the "item_type" and "types."

GBDX Notebooks

This example shows how to retrieve Sentinel-1 data in the GBDX Notebooks environment. You must be logged in to GBDX Notebooks to see it.
<a href="https://notebooks.geobigdata.io/hub/notebooks/05c0uyupni3g9c862lgy?tab=code" target="_blank" rel="noopener".GBDX Notebooks Sentinel-1 example

GBDXTools

This example shows how to search for Sentinel-1 data using GBDXtools:

Python

from gbdxtools import Interface
gbdx = Interface()

aoi = "POLYGON ((-105.35202026367188 39.48113956424843, -105.35202026367188 40.044848254075546, -104.65988159179688 40.044848254075546, -104.65988159179688 39.48113956424843, -105.35202026367188 39.48113956424843))"
query = 'item_type:SENTINEL1'
images = gbdx.vectors.query(aoi, query)      

print('Images: {}'.format(len(images)))
print("Show first return!")
images[0]

See gbdxtools Response example

Using the GBDX VectorService API, search by "item_type" to find Sentinel-1 data. To narrow down the search results set, include area, date range, or both. Search results can be further filtered by data attributes, can be sorted by properties, and the number of results returned can be set.

Vector Services Index Query Reference Overview

API Headers

Authorization: Bearer [[token]]
Content-type: application/json

To retrieve a subset of results, send a POST request to

//vector.geobigdata.io/insight-vector/api/index/query/vector-gbdx-alpha-catalog-v2*/items?q=item_type:SENTINEL1&count=10` with a request body.

JSON

{
    "coordinates": [[[-105.35202026367188, 39.48113956424843], [-105.35202026367188, 40.044848254075546], [-104.65988159179688, 40.044848254075546], [-104.65988159179688, 39.48113956424843], [-105.35202026367188, 39.48113956424843]]],
    "type": "Polygon"
}

To retrieve all results, use a paging request instead. Send a POST request to

//vector.geobigdata.io/insight-vector/api/index/query/vector-gbdx-alpha-catalog-v2*/paging?q=item_type:SENTINEL1&ttl=5m&sort=item_date:asc

JSON

{
    "coordinates": [[[-105.35202026367188, 39.48113956424843], [-105.35202026367188, 40.044848254075546], [-104.65988159179688, 40.044848254075546], [-104.65988159179688, 39.48113956424843], [-105.35202026367188, 39.48113956424843]]],
    "type": "Polygon"
}

Catalog API

Using the GBDX Catalog V2 API, search by "types" to find Sentinel-1 data. To narrow the search results set, include area, date range, or both. Search results can be further filtered by properties.

API Headers:

Authorization: Bearer [[token]]
Content-type: application/json

Send a POST request to

//geobigdata.io/catalog/v2/search

with a request body. This is an example:

JSON

     {
    "searchAreaWkt": "POLYGON ((-105.35202026367188 39.48113956424843, -105.35202026367188 40.044848254075546, -104.65988159179688 40.044848254075546, -104.65988159179688 39.48113956424843, -105.35202026367188 39.48113956424843))",
    "startDate": "2017-01-01T00:00:00.000Z",
    "endDate": "2018-12-31T23:59:59.999Z",
    "types": ["SENTINEL1"]
     }

See Catalog API Example

Back to top

Types

These are the "types" associated with Sentinel-1 records. For gbdxtools and VectorService API requests, the type is referred to as "item_type." For Catalog V2 API requests, the type is referred to as "types."

Back to top

Properties

The following properties and metadata files are associated with a Sentinel-1 record in the GBDX catalog.

Catalog ID

The Catalog ID is the product ID assigned by the vendor.

This is what a Sentinel-1 catalog ID looks like:

S1A_IW_GRDH_1SDV_20181218T130110_20181218T130139_025080_02C497_D1A7

The segments of the example catalog ID are defined in this table:

Beam Modes

• Stripmap (SM) – A standard SAR stripmap imaging mode where the ground swath is illuminated with a continuous sequence of pulses while the antenna beam is pointing to a fixed azimuth and elevation angle.

• Interferometric Wide Swath (IW) – Data is acquired in 3 swaths using the Terrain Observation with Progressive Scanning SAR (TOPSAR) imaging technique. In IW mode bursts are synchronized from pass to pass to ensure the alignment of interferometric pairs.

• Extra Wide Swath (EW) – Data is acquired in 5 swaths using the TOPSAR imaging technique. EW mode provides very large swath coverage at the expense of spatial resolution.

• Wave (WV) – Data is acquired in small stripmap scenes called “vignettes”, situated at regular intervals of 100 km along track. The vignettes are acquired in ‘leap frog’ mode; i.e., one vignette is acquired at a near range incidence angle while the next vignette is acquired at a far range incidence angle.

• Elevation Notch (EN) and Azimuth Notch (AN) – The notch acquisition modes are instrument calibration modes used for the determination of elevation pointing. They are fully based on SM acquisition parameters with the main difference being the excitation coefficients used during the acquisition of measurement data.

Source: Sentinel-1 Product Specification

Resolution Classes

Resolution class is not part of the product's properties. It can be found in the unique identifier for the record ("identifier" or catalogID.

Polarizations

S3 Location

The s3 location for an image product is :

The bucketName and bucketPrefix are properties in the response body below.

Example:

s3:// sentinel-s1-l1c/GRD/2017/8/1/IW/DV/S1A_IW_GRDH_1SDV_20170801T130102_20170801T130131_017730_01DB29_4DC8

Back to top

Response Examples

gbdxtools Response Example

PYTHON

Images: 100
Show first return!
{'type': 'Feature',
 'geometry': {'type': 'MultiPolygon',
  'coordinates': [[[[-107.8145859792547, 39.53237834235411],
     [-107.4238949182782, 38.03250825688781],
     [-104.4980165974277, 38.43611116198831],
     [-104.8255350255155, 39.93505138733975],
     [-107.8145859792547, 39.53237834235411]]]]},
 'properties': {'ingest_source': 'GBDX_INGEST_ALPHA',
  'item_date': '2017-03-16T01:01:10.835Z',
  'original_crs': 'EPSG:4326',
  'item_type': ['GBDXCatalogRecord', 'ESAProduct', 'SENTINEL1'],
  'name': None,
  'format': None,
  'ingest_date': '2019-02-02T02:36:27.295Z',
  'attributes': {'passDirection': 'Ascending',
   'beamMode': 'Interferometric Wide Swath',
   'bucketName': 'sentinel-s1-l1c',
   'absoluteOrbitNumber': '4727',
   'sensorPlatformName': 'SENTINEL1B-C-SAR',
   's3Region': 'eu-central-1',
   'footprintWkt': 'POLYGON ((-107.8145859792547014 39.5323783423541073, -107.4238949182781937 38.0325082568878088, -104.4980165974277071 38.4361111619883076, -104.8255350255155065 39.9350513873397475, -107.8145859792547014 39.5323783423541073))',
   'imageNumber': '1',
   'groundSampleDistance': '10.0',
   'azimuthPixelSpacing': '10.0',
   'beams': 'IW',
   'catalogID': 'S1B_IW_GRDH_1SDV_20170316T010110_20170316T010135_004727_008411_14C3',
   'vendor': 'European Space Administration',
   'bucketPrefix': 'GRD/2017/3/16/IW/DV/S1B_IW_GRDH_1SDV_20170316T010110_20170316T010135_004727_008411_14C3',
   'id': 'S1B_IW_GRDH_1SDV_20170316T010110_20170316T010135_004727_008411_14C3',
   'incidenceAngleMidSwath': '39.28352606638745',
   'lookDirection': 'Right',
   'platformName': 'SENTINEL1B',
   'polarizations': ['VH', 'VV'],
   'productType': 'GRD',
   'rangePixelSpacing': '10.0',
   'timestamp': '2017-03-16T01:01:10.835030'},
  'ingest_attributes': {'_rest_user': '[email protected]',
   '_rest_url': [full path url]
  'id': 'S1B_IW_GRDH_1SDV_20170316T010110_20170316T010135_004727_008411_14C3',
  'source': None,
  'text': ''}}

Vector Services Response Example

JSON

[
    {
        "geometry": {
            "coordinates": [
                [
                    [
                        [
                            -107.8145859792547,
                            39.53237834235411
                        ],
                        [
                            -107.4238949182782,
                            38.03250825688781
                        ],
                        [
                            -104.4980165974277,
                            38.43611116198831
                        ],
                        [
                            -104.8255350255155,
                            39.93505138733975
                        ],
                        [
                            -107.8145859792547,
                            39.53237834235411
                        ]
                    ]
                ]
            ],
            "type": "MultiPolygon"
        },
        "type": "Feature",
        "properties": {
            "ingest_source": "GBDX_INGEST_ALPHA",
            "item_date": "2017-03-16T01:01:10.835Z",
            "original_crs": "EPSG:4326",
            "item_type": [
                "GBDXCatalogRecord",
                "ESAProduct",
                "SENTINEL1"
            ],
            "name": null,
            "format": null,
            "ingest_date": "2019-02-02T02:36:27.295Z",
            "attributes": {
                "passDirection": "Ascending",
                "beamMode": "Interferometric Wide Swath",
                "bucketName": "sentinel-s1-l1c",
                "absoluteOrbitNumber": "4727",
                "sensorPlatformName": "SENTINEL1B-C-SAR",
                "s3Region": "eu-central-1",
                "footprintWkt": "POLYGON ((-107.8145859792547014 39.5323783423541073, -107.4238949182781937 38.0325082568878088, -104.4980165974277071 38.4361111619883076, -104.8255350255155065 39.9350513873397475, -107.8145859792547014 39.5323783423541073))",
                "imageNumber": "1",
                "groundSampleDistance": "10.0",
                "azimuthPixelSpacing": "10.0",
                "beams": "IW",
                "catalogID": "S1B_IW_GRDH_1SDV_20170316T010110_20170316T010135_004727_008411_14C3",
                "vendor": "European Space Administration",
                "bucketPrefix": "GRD/2017/3/16/IW/DV/S1B_IW_GRDH_1SDV_20170316T010110_20170316T010135_004727_008411_14C3",
                "id": "S1B_IW_GRDH_1SDV_20170316T010110_20170316T010135_004727_008411_14C3",
                "incidenceAngleMidSwath": "39.28352606638745",
                "lookDirection": "Right",
                "platformName": "SENTINEL1B",
                "polarizations": [
                    "VH",
                    "VV"
                ],
                "productType": "GRD",
                "rangePixelSpacing": "10.0",
                "timestamp": "2017-03-16T01:01:10.835030"
            },
            "ingest_attributes": {
                "_rest_user": "[email protected]",
                "_rest_url": "http://vector.geobigdata.io/api/vectors/gbdx-alpha-catalog-v2-%257Bitem_date%253Ayyyy%257D"
            },
            "id": "S1B_IW_GRDH_1SDV_20170316T010110_20170316T010135_004727_008411_14C3",
            "source": null,
            "text": ""
        }
    }
[results truncated]

Catalog API Response Example

JSON

   {
    "stats": {
        "recordsReturned": 8,
        "totalRecords": 8,
        "typeCounts": {
            "ESAProduct": 8,
            "SENTINEL1": 8,
            "GBDXCatalogRecord": 8
        }
    },
    "results": [
        {
            "identifier": "S1A_IW_GRDH_1SDV_20170801T130102_20170801T130131_017730_01DB29_4DC8",
            "type": [
                "GBDXCatalogRecord",
                "ESAProduct",
                "SENTINEL1"
            ],
            "properties": {
                "beamMode": "Interferometric Wide Swath",
                "imageNumber": "1",
                "rangePixelSpacing": "10.0",
                "azimuthPixelSpacing": "10.0",
                "absoluteOrbitNumber": "17730",
                "id": "S1A_IW_GRDH_1SDV_20170801T130102_20170801T130131_017730_01DB29_4DC8",
                "groundSampleDistance": "10.0",
                "catalogID": "S1A_IW_GRDH_1SDV_20170801T130102_20170801T130131_017730_01DB29_4DC8",
                "timestamp": "2017-08-01T13:01:02.331Z",
                "platformName": "SENTINEL1",
                "polarizations": [
                    "VH",
                    "VV"
                ],
                "vendor": "European Space Administration",
                "beams": "IW",
                "bucketPrefix": "GRD/2017/8/1/IW/DV/S1A_IW_GRDH_1SDV_20170801T130102_20170801T130131_017730_01DB29_4DC8",
                "passDirection": "Descending",
                "bucketName": "sentinel-s1-l1c",
                "s3Region": "eu-central-1",
                "footprintWkt": "MULTIPOLYGON(((-105.686650293 39.7367121522, -102.752774026 39.3389314097, -102.303145927 41.0823728686, -105.314034212 41.4790535248, -105.686650293 39.7367121522)))",
                "productType": "GRD",
                "sensorPlatformName": "SENTINEL1-C-SAR",
                "lookDirection": "Right",
                "incidenceAngleMidSwath": "38.99983036574982"
            }
  
          [results truncated]

Back to top

Contact

If you have any questions or issues with this task, please contact [email protected].