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Alaska Hindcast Wave Data (/api/wave/v2/wave/alaska-hindcast-download)

Collect and download, as CSV, a configurable set of wave data fields from the DOE-WPTO.

This API is capable of creating very large downloadable archives. Unlike a typical API, the response to this provides a request acknowledgement. The real work of creating the requested downloadable archive will continue to run on the server side. When complete, and email will be sent to the email address provided in the initial request with a link to a file to download. In addition to this two step workflow, there is also an option for users who wish to download a single CSV file in direct response to an API request. The .csv format may be used to download a CSV directly. This feature is restricted to use with only a single POINT, for a single YEAR at a time.

Request URL

GET|POST /api/wave/v2/wave/alaska-hindcast-download.format?parameters

Request Parameters

NOTE: when using POST to submit a request the api_key must still be included as a query parameter in the url. All other parameters may be included in a POST request as part of the payload.

Parameter Required Value Description
api_key Yes
Type: string
Default: None

Your developer API key. See API keys for more information.

wkt Yes
Type: well-known text string
Default: None
A well-known text (WKT) representation of the geometry for which to extract data. May be a point, multipoint, or polygon geometry. When a point is passed the site nearest to that point is used. When a multipoint is passed the site nearest each point is used. This can be useful for downloading multiple sites in a single request when those sites are geographically distant from each other. When a polygon is passed all sites that intersect with the given polygon are used.
attributes No
Type: comma delimited string array
Default: Returns ALL
Options: directionality_coefficient, energy_period, maximum_energy_direction, mean_absolute_period, mean_wave_direction, mean_zero-crossing_period, omni-directional_wave_power, peak_period, significant_wave_height, spectral_width, time_index, water_depth
Each specified attribute(*) will be returned as a column in the resultant CSV download.
names Yes
Type: comma delimited string array
Default: None
Options: 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010.
The year(s) for which data should be extracted.
utc No
Type: true or false
Default: true
Pass true to retrieve data with timestamps in UTC. Pass false to retrieve data with timestamps converted to local time of data point (without daylight savings time).
leap_day No
Type: true or false
Default: false
Pass true to retrieve data including leap day (where appropriate). Pass false to retrieve data excluding leap day.
interval Yes
Type:180
Default: None
This value determines data resolution. 180 minute intervals are available.
full_name No
Type: string
Default: None
The full name of the user requesting data.
email Yes
Type: email string
Default: None
An active email for the user requesting data. This email will be used to deliver the extracted data.
affiliation No
Type: string
Default: None
The organization with which the user requesting the data is affiliated.
reason No
Type: string
Default: None
The reason that the user is requesting the data.
mailing_list No
Type: true or false
Default: false
Pass true to add the email address to our list of recipients for the NSRDB mailing list.

Response Fields

The response is composed of service-related informational fields and the results of the data query.

Field Value Description
errors
Type: string array

A list of error messages

inputs
Type: Object Hash
Key: Value pairs representing all input parameters
outputs
Type: Object Hash
Upon successful completion a message will be returned informing the user that file generation is in progress and an email will be sent to the address provided in the email input field when the download is ready

Data File Format

Generated data files are formatted in accordance with the Standard Time Series Data File Format. This file format has been developed to support SAM and other NREL models and is documented fully in this PDF. More information on SAM file formats available on the SAM weather page.

Examples

JSON Output Format

GET /api/wave/v2/wave/alaska-hindcast-download.json?api_key=DEMO_KEY&full_name=Sample+User&email=user@company.com&affiliation=Test+Organization&reason=Example&mailing_list=true&wkt=POINT (-160.491356 54.040203)&names=2010&utc=true&leap_day=true
{
    "inputs": {
        "body": {},
        "params": {},
        "query": {
            "utc": "true",
            "leap_day": "true",
            "interval": "180",
            "email": "user@company.com",
            "wkt": "POINT (-160.491356 54.040203)",
            "names": "1979"
        }
    },
    "metadata": {
        "version": "2.0.0",
        "resultset": {
            "count": 1
        }
    },
    "status": 200,
    "outputs": {
        "message": "File generation in progress. An email will be sent to user@company.com when the download is ready.",
        "downloadUrl": "https://mapfiles.nrel.gov/data/wave/f725f109a565fb482c4a99cdac70c6a8.zip"
    },
    "errors": []
}

CSV Output Format

Direct streaming of CSV data is supported for single location, single year only. The following response example is truncated after the first few rows of data.

GET /api/wave/v2/wave/alaska-hindcast-download.csv?api_key=DEMO_KEY&full_name=Sample+User&email=user@company.com&affiliation=Test+Organization&reason=Example&mailing_list=true&wkt=POINT (-160.491356 54.040203)&names=1979&utc=true&leap_day=true
Source,Location ID,Jurisdiction,Latitude,Longitude,Time Zone,Local Time Zone,Distance to Shore,Directionality Coefficient,Energy Period,Maximum Energy Direction,Mean Absolute Period,Mean Wave Direction,Mean Zero-Crossing Period,Omni-Directional Wave Power,Peak Period,Significant Wave Height,Spectral Width,Water Depth,Version
DOE-WPTO US Wave dataset,622416,b'Federal',54.040188,-160.49251,0,-10,93273.016,-,s,deg,s,deg,s,W/m,s,m,-,2182,v1.0.0
Year,Month,Day,Hour,Minute,Directionality Coefficient,Energy Period,Maximum Energy Direction,Mean Absolute Period,Mean Zero-Crossing Period,Omni-Directional Wave Power,Peak Period,Significant Wave Height,Spectral Width
1979,1,7,0,0,0.8358079791069031,7.4664998054504395,172.5,8.162799835205078,9.088500022888184,89305,10.01200008392334,4.475830078125,0.2716299891471863
1979,1,7,3,0,0.833549976348877,7.552000045776367,172.5,8.247599601745605,9.172200202941895,84087,10.01200008392334,4.323190212249756,0.26954999566078186
1979,1,7,6,0,0.8325499892234802,7.384900093078613,172.5,8.099699974060059,9.053199768066406,77718,10.01200008392334,4.183579921722412,0.2759400010108948

POST request example in Python

import requests

url = "http://developer.nrel.gov/api/wave/v2/wave/alaska-hindcast-download.json?api_key=yourapikeygoeshere"

payload = "full_name=Sample+User&email=user@company.com&affiliation=Test+Organization&reason=Example&mailing_list=true&wkt=POINT (-160.491356 54.040203)&names=2010&utc=true&leap_day=true"

headers = {
    'content-type': "application/x-www-form-urlencoded",
    'cache-control': "no-cache"
}

response = requests.request("POST", url, data=payload, headers=headers)

print(response.text)

Rate Limits

Rate limits for this application are significantly less than the standard rate limits for developer.nrel.gov. This decrease in the limit is required as the data provided through this service is significantly more computationally intensive to generate and provide. These rate limits are carefully calculated to allow all users the maximum throughput that our servers can sustain.

There are several levels of rate limiting for this service. The first limit determines how many requests a given user can make per 24 hour period. For requests utilizing the .csv format this rate limit is set at 5000 a day at a frequency of no more than 1 per second. For all other requests this limit is set at 1000 requests per day at a frequency of no more than 1 every 2 seconds.

Secondly each user is limited to 20 in-flight requests at any given time.

In addition, the service has a fail-safe mechanism to prevent significant performance decreases that can be caused by unexpectedly high usage of the service. This limit will cause the service to stop accepting requests when the queue reaches a point where additional requests will significantly lower server performance. When this limit is hit, the service will error with a message describing that the request queue is full.

For some tips and tricks to maximize data downloads please read the guide here.

Errors

Standard errors may be returned. In addition, the following service-specific errors may be returned:

HTTP Status Code Description
400 Bad Request: When required parameters are missing.
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