Alaska Satellite Facility
Delivering Remote Sensing Data Since 1991

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Construct and test API searches
for synthetic aperture radar (SAR) at ASF

  1. Type keywords and values into the upper box
  2. Execute to see the full API command and the search results below

Users may copy the resulting cURL command for use at the command line or in their own scripts.

Program   Base URL                                             Keywords and values
curl      https://api.daac.asf.alaska.edu/services/search/param?keyword=value\&...
For more information on the SSARA Federated API, see InSAR Download Data.

Keyword Syntax Hints
    ·Don't leave spaces between characters.
    ·Keywords are case sensitive.
    ·Some keyword values require URL encoding.
    ·Connect keywords with '\&' for cURL and Wget.
    ·Connect keywords with '&' for browser searches.
   

API Keywords

Click keywords to expand

For ALOS, ERS-1, ERS-2, JERS-1, and RADARSAT-1, Sentinel-1A, Sentinel-1B this value corresponds to the orbit count within the orbit cycle. For UAVSAR it is the Flight ID.

Examples:
RADARSAT: absoluteOrbit=25436;
PALSAR: absoluteOrbit=25436-25445, 25450;
UAVSAR: absoluteOrbit=12006

This is primarily an ASF / JAXA frame reference. However, some platforms use other conventions. See 'frame' for ESA-centric frame searches.

Values:
Any valid number, series of numbers, or number range for a given platform.

  • ERS, JERS, RADARSAT: ASF frames 0 to 900.
  • ALOS PALSAR: JAXA frames 0 to 7200.
  • SEASAT: ESA-like frames 0208 to 3458  (must use a leading zero for frames 208-999).
  • Sentinel-1: In-house values 0 to 1184.

Note:
Use in-range value for a successful search.

Examples:
asfframe=300 or asfframe=2845-2855 or asfframe=2800,2845-2855

For interferometric SAR (InSAR) analysis, Perpendicular Baseline is the spatial distance between the first and second observations measured perpendicular to the satellite look direction and provides an indication of the sensitivity to topographic height.

Works for ERS-1, ERS-2, JERS, RADARSAT-1, ALOS PALSAR. (Not Sentinel-1)

Example:
maxBaselinePerp=1500 or maxBaselinePerp=50.5

For interferometric SAR (InSAR) analysis, Perpendicular Baseline is the spatial distance between the first and second observations measured perpendicular to the satellite look direction and provides an indication of the sensitivity to topographic height.

Works for ERS-1, ERS-2, JERS, RADARSAT-1, ALOS PALSAR. (Not Sentinel-1)

Example:
minBaselinePerp=100 or minBaselinePerp=50.5

Bounding boxes define an area using two long/lat points. The Bounding box parameters are 4 comma-separated numbers: lower left longitude,latitude, and upper right longitude,latitude. Best choice for very wide search areas.

Example:
bbox=-150.2,65.0,-150.1,65.5

The beam mode used to acquire the data. See also beamSwath.

Example:
beamMode=FBS or beamMode=EW,IW or beamMode=ScanSAR+Wide (URL encoding required for space in name)

PLATFORMValues
AIRSAR3FP, ATI, XTI
ALOSFBD, FBS, PLR, WB1, WB2, DSN
ERS-1Standard, STD
ERS-2Standard, STD
JERS-1Standard, STD
RADARSAT-1Standard, STD, Fine, High, Low, Wide, Narrow, ScanSAR+Wide, ScanSAR+Narrow
SEASATStandard, STD
SMAPStandard, STD
Sentinel-1AEW, IW, S1, S2, S3, S4, S5, S6, WV
Sentinel-1BEW, IW, S1, S2, S3, S4, S5, S6, WV
UAVSARPOL, RPI

BeamSwath encompases a look angle and beam mode.

Example:
beamSwath=0 or beamswadth or beamSwath=FN1,FN2,FN3,FN4,FN5

PLATFORMValues
AIRSAR3FP, ATI, XTI
ALOS1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 15, 16, 17, 18, 19, 20
ERS-1STD
ERS-2STD
JERS-1STD
RADARSAT-1FN1, FN2, FN3, FN4, FN5, SNA, SNB, ST1, ST2, ST3, ST4, ST5, ST6, ST7, SWA, SWB, WD1, WD2, WD3, EH3, EH4, EH6, EL1
SEASATSTD
Sentinel-1AEW, IW, S1, S2, S3, S4, S5, S6, WV
Sentinel-1BEW, IW, S1, S2, S3, S4, S5, S6, WV
UAVSARPOL, RPI

For UAVSAR and AIRSAR data collections only. Search by general location, site description, or data grouping as supplied by flight agency or project.

Example:
collectionName=Haiti

More examples:
UAVSAR: collectionName=Iceland collectionName=earthquake; AIRSAR: collectionName=Denali

Doppler provides an indication of how much the look direction deviates from the ideal perpendicular flight direction acquisition.

Example:
maxDoppler=1500 or maxDoppler=1500.5

Doppler provides an indication of how much the look direction deviates from the ideal perpendicular flight direction acquisition.

Example:
minDoppler=100 or minDoppler=1500.5

Rotation of the polarization plane of the radar signal impacts imagery. HH and HV signals become mixed.

One-way rotations exceeding 5° are likely to significantly reduce the accuracy of geophysical parameter recovery, such as forest biomass.

Example:
maxFaradayRotation=3.5

Rotation of the polarization plane of the radar signal impacts imagery. HH and HV signals become mixed.

Example:
minFaradayRotation=2

Satellite orbit direction during data acquisition.

Example:
flightDirection=DESCENDING

Values:
A, ASC, ASCENDING, D, DESC, DESCENDING

Specify a flightline for UAVSAR or AIRSAR.

Example:
UAVSAR: flightLine=05901
AIRSAR: flightLine=gilmorecreek045-1.93044

ESA-referenced frames are offered to give users a universal framing convention. Each ESA frame has a corresponding ASF frame assigned. See also 'asfframe'.

Note:
The asfframe number rather than the ESA frame number will be returned in your search metalink file.

Example:
frame=300
frame=300-400
frame=300,303,305
frame=300,303,305-315

Values:
Any number from 0 to 7200.

Comma-separated list of specific granules. Large lists will need to utilize a POST request. Note: specifying a granule list will cause most other keywords to be ignored including output. 

Example:
granule_list=R1_12345_FN1_F001,R1_12345_FN1_F002

An InSAR stack is composed of all SAR granules that cover the same geographic region, are from the same platform, and were acquired with the same beam mode, look angle, and bandwidth. To obtain InSAR stacks containing a certain number of SAR granules specify a min, max, or both.

Works for ERS-1, ERS-2, JERS, RADARSAT-1, ALOS PALSAR. (Not Sentinel-1)

Example:
maxInsarStackSize=175

An InSAR stack is composed of all SAR granules that cover the same geographic region, are from the same platform, and were acquired with the same beam mode, look angle, and bandwidth. To obtain InSAR stacks containing a certain number of SAR granules specify a min, max, or both.

Works for ERS-1, ERS-2, JERS, RADARSAT-1, ALOS PALSAR. (Not Sentinel-1)

Example:
minInsarStackSize=20

Search by polygon, a line segment ("linestring"), or a point defined in 2-D Well-Known Text (WKT). Each polygon must be explicitly closed, i.e. the first vertex and the last vertex of each listed polygon must be identical. Coordinate pairs for each vertex are in decimal degrees: longitude is followed by latitude.

Note:
 1) Does not support multi-polygon, multi-line or multi-point.
 2) Polygon holes are ignored

Examples (need URL encoding):

intersectsWith=polygon((-119.543 37.925, -118.443 37.7421, -118.682 36.8525, -119.77 37.0352, -119.543 37.925 ))

intersectsWith=linestring(-119.543 37.925, -118.443 37.7421)

intersectsWith=point(-119.543,37.925)

Properly URL encoded:
intersectsWith=point%28-119.543+37.925%29

NOTE!
For successful searches, URLs and keywords may not contain spaces or parentheses. Encode as shown below.

Encoding
URLReplace with
comma ,
space +
(%28
)%29

Reference: wc3 URL encoding reference.

Left or right direction of data acquisition.

Example:
lookDirection=L

Values:
R, RIGHT, L, LEFT

Off-nadir angles for ALOS PALSAR

Example:
offNadirAngle=21.5
offNadirAngle=9.7-14
offNadirAngle=21.5,23.1,20.5-24.2

Values:
Most common: 21.5, 23.1, 27.1, 34.3 
Other: 9.7, 9.9, 13.8, 14, 16.2, 17.3, 17.9, 18, 19.2, 20.5, 21.5, 23.1, 24.2, 24.6, 25.2, 25.8, 25.9, 26.2, 27.1, 28.8, 30.8, 34.3, 36.9, 38.8, 41.5, 43.4, 45.2, 46.6, 47.8, 49, 50, 50.8

Format of the API search results returned. If not specified, default return is metalink for ASF API or JSON for SSARA Federated API. MAP setting valid only for SSARA Federated API.

Example:
output=JSON

Values:
CSV, JSON, KML, METALINK, COUNT, DOWNLOAD, GEOJSON

NEW values!
COUNT returns the number of search results
GEOJSON returns the search results in a GeoJSON format
DOWNLOAD returns a bulk download script that includes the scenes returned by the search. 
For a full description and guide on using the bulk download script itself, please see https://www.asf.alaska.edu/data-tools/bulk-download/

Note:
JSON returns more fields than CSV for the same query.

Remote sensing platform that acquired the data. Datasets that work together, such as Sentinel 1A/1B and ERS‌-1/2 have multi-platform aliases available (specifically, S1 and ERS).

Example:
platform=ALOS
platform=SA, SB
platform=S1

Values:
‌ALOS, A3, AIRSAR, AS, ERS, ERS‌-1, E1, ERS‌-2, E2, JERS‌-1, J1, RADARSAT‌-1, R1, SEASAT, SS, S1, Sentinel, Sentinel-1, Sentinel-1A, SA, Sentinel-1B, SB, SMAP, SP, UAVSAR, UA.

A property of SAR electromagnetic waves that can be used to extract meaningful information about surface properties of the earth.

Examples:
polarization=VV
polarization=VV, HH
polarization=VV%2bVH
polarization=Dual+VV
Encode "+" and "[space]" as shown below.

Encoding
URLReplace with
space +
+%2B
PLATFORMValues (some values require encoding)
AIRSARFULL
ALOSQUADRATURE, HH+5SCAN, HH, HH+4SCAN, VV, HH+3SCAN, FULL, HH+HV, VV+VH
ERS-1VV
ERS-2VV
JERS-1HH
RADARSAT-1HH
SEASATHH
Sentinel-1AVV, VV+VH, Dual VV, VV+VH, Dual HV, HH, HH+HV, VV, Dual VH
Sentinel-1BVV, VV+VH, Dual VV, VV+VH, Dual HV, HH, HH+HV, VV, Dual VH
UAVSARFULL, HH

Bounding polygon in the digital long/lat format; enter coordinates in counter clockwise direction, repeat the first point at the end to close the polygon: in the format ABCDA

Example:
polygon=-155.08,65.82,-153.5,61.91,-149.50,63.07,-149.94,64.55,-153.28,64.47,-155.08,65.82

Level to which the data has been processed, also type of product, such as browse.

Example:
processingLevel=L0,L1

PLATFORMValues
AIRSAR3FP, ATI, LTIF, PTIF, CTIF, PSTOKES, BROWSE, DEM, CSTOKES, JPG, LSTOKES, THUMBNAIL
ALOSL1.0, L1.1, L1.5, RTC_LOW_RES, RTC_HI_RES, BROWSE, THUMBNAIL, METADATA, INTERFEROMETRY
ERS-1L0, L1, BROWSE, THUMBNAIL
ERS-2L0, L1, BROWSE, THUMBNAIL
JERS-1L0, L1, BROWSE, THUMBNAIL
RADARSAT-1L0, L1, BROWSE, THUMBNAIL
SEASATL1, BROWSE, THUMBNAIL
Sentinel-1AMETADATA_GRD, GRD_HS, GRD_HD, GRD_MS, GRD_MD, GRD_FS, GRD_FD, SLC, RAW, OCN, METADATA_RAW, METADATA, METADATA_SLC, THUMBNAIL
Sentinel-1BMETADATA_GRD, GRD_HS, GRD_HD, GRD_MS, GRD_MD, GRD_FS, GRD_FD, SLC, RAW, OCN, METADATA_RAW, METADATA, METADATA_SLC, THUMBNAIL
SMAPL1A_Radar_RO_QA, L1B_S0_LoRes_HDF5, L1B_S0_LoRes_QA, L1B_S0_LoRes_ISO_XML, L1A_Radar_QA, L1A_Radar_RO_ISO_XML, L1C_S0_HiRes_ISO_XML, L1C_S0_HiRes_QA, L1C_S0_HiRes_HDF5, L1A_Radar_HDF5
UAVSARKMZ, PROJECTED, PAULI, PROJECTED_ML5X5, STOKES, AMPLITUDE, BROWSE, COMPLEX, DEM_TIFF, PROJECTED_ML3X3, METADATA, AMPLITUDE_GRD, INTERFEROMETRY, INTERFEROMETRY_GRD, THUMBNAIL

Path or track of satellite during data acquisition. For UAVSAR it is the Line ID.

Example:
relativeOrbit=500,550-580 or UAVSAR: relativeOrbit=05905

PLATFORMValues
ALOS1-671
ERS-10-2410
ERS-20-500
JERS-10-658
RADARSAT-10-342
SEASAT1-243
UAVSAR various

Maximum number of data records to return from your query. 

Example:
maxResults=10

Limit results to records that have been processed at ASF since a given date and time.

Example:
processingDate=2017-01-01T00:00:00UTC

Date of data acquisition

Natural language
Use phrases such as:
  • start=3 months and a day ago 
  • start=May 30, 2018
  • end=now

Insert '+' in place of spaces.

Example:
platform=SB&start=1+week+ago&end=now
&maxresults=2000&output=csv

UTC
Enter a start date, end date or both to form a valid range.

Example:
start=2010-10-30T11:59:59UTC\&end=2018-10-01T00:00:00UTC

Start and end day of year for desired seasonal range. This keyword is used in conjunction with start/end to specify a seasonal range within an overall date range in choosing values in alignment with Julian calendar.

Example:
season=1,31
season=45,67
season=360,10

Values:
1 through 365

Deprecated Keywords

KeywordNote
beamSee beamMode
directionSee flightDirection
formatSee output
limitSee maxResults
lookAngleSee offNadirAngle
minPercentCoherenceDeprecated
minPercentTroposphereDeprecated
minPercentUnwrappedDeprecated
orbitSee absoluteOrbit
offnadirSee offNadirAngle
pathSee relativeOrbit
processingSee processingLevel
slaveStart/SlaveEndDeprecated
varianceTroposphereDeprecated

API Results

cURL Command Executed

Get SAR Data

Get SAR Data

Select and download SAR data online using Vertex.

Use the ASF API for downloading SAR data via a command line.