NICAM-LETKF JAXA Research Analysis (NEXRA) version 3.0

  • DOI: 10.57746/EO.01kvpvy6pv99x5p73v1gde1v1z
  • Last Updated: 2026-06-25
Data Progress: In Work
NEXRA_logo

Product Summary

NEXRA is a unique weather data assimilation system using NICAM-LETKF jointly developed with the University of Tokyo and RIKEN. NICAM-LETKF assimilates in-situ observation, satellite radiance, and precipitation data. It provides current surface wind direction and wind speed, surface air temperature, surface water vapor amount, total precipitable water, surface pressure, accumulated precipitation, and Outgoing Longwave Radiation (OLR). It is currently produced four times a day using 128 ensemble members.
In version 3, the ensemble mean and spread of 128 members generated from the data assimilation cycle are provided on about 0.56-degree latitude-longitude grid with 26 vertical levels (anl_3d). Similarly, ensemble mean and spread of 128 members for surface data (anl_2d) is also provided on about 0.56-degree latitude-longitude grid. In addition, we also provide single-member forecast data from the 6-hourly assimilation cycle (fcst_2d). The data cover the forecast period from 1 day to 1 day and 6 hours after the initial forecast time, at a resolution of about 1.4-degree latitude-longitude grid.

Platform
Model
Sensor
N/A

Coverage

Temporal Coverage

2024-01-01 to Present

Spatial Coverage

Bounding Rectangle

Resolution

【 anl_3d 】 latitude · longitude : 0.5625 degree
vertical : 1000, 975, 950, 925, 900, 850, 800, 750, 700, 650, 600, 550, 500, 450, 400, 350, 300, 250, 200, 150, 100, 70, 50, 30, 20, 10 [hPa]
【 anl_2d 】 latitude · longitude : 0.5625 degree
【 fcst_2d 】 latitude · longitude : 0.140625 degree

Location

  • GEOGRAPHIC REGION > GLOBAL
Dataset Short Name
NICAM-LETKF_JAXA_Research_Analysis_NEXRA3
Platform / Sensor
Model / N/A
Coverage
Spatial Coverage
Bounding Rectangle
Temporal Coverage
2024-01-01 to Present
Product Level ID
L4
Version Description

Ver.3, 2024-01-01, Available

File Format
NetCDF
Dataset Type
6-hourly / Global
Resolution
Spatial Resolution
【 anl_3d 】
latitude · longitude : 0.5625 degree
vertical : 1000, 975, 950, 925, 900, 850, 800, 750, 700, 650, 600, 550, 500, 450, 400, 350, 300, 250, 200, 150, 100, 70, 50, 30, 20, 10 [hPa]
【 anl_2d 】
latitude · longitude : 0.5625 degree
【 fcst_2d 】
latitude · longitude : 0.140625 degree
Temporal Resolution
6-hourly
Dataset Progress
In Work
Projection
EQR
Collection Data Type
SCIENCE_QUALITY
Get Data
https://www.eorc.jaxa.jp/theme/NEXRA/registration.html
Dataset Title
NICAM-LETKF JAXA Research Analysis (NEXRA) version 3.0
Distribution Format
NetCDF
Fees
Free
Citation
Japan Aerospace Exploration Agency. 2024. NICAM-LETKF JAXA Research Analysis (NEXRA) version 3.0. https://doi.org/10.57746/EO.01kvpvy6pv99x5p73v1gde1v1z
Access Constraints

No constraints but users need to be registered via following registration form to download files. https://www.eorc.jaxa.jp/theme/NEXRA/registration.html

Use Constraints

The user should comply with the following terms when using the images and data (https://earth.jaxa.jp/en/data/policy/). Users should specify the following sentence when they publish a thesis, a report, and so on by using the dataset. "NEXRA product that was used in this paper was develop by Japan Aerospace Exploration Agency (JAXA), The University of Tokyo, and RIKEN."

NEXRA Terms of service
https://www.eorc.jaxa.jp/theme/NEXRA/registration.html
ISO Topic Categories
  • Climatology/Meteorology/Atmosphere
  • Environment
Science Keywords
  • EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC RADIATION
  • EARTH SCIENCE > ATMOSPHERE > CLOUDS
  • EARTH SCIENCE > ATMOSPHERE > PRECIPITATION
  • EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC PRESSURE
  • EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC TEMPERATURE
  • EARTH SCIENCE > ATMOSPHERE > ATMOSPHERIC WATER VAPOR
Location Keywords
  • GEOGRAPHIC REGION > GLOBAL
ECV and other Keywords
  • Wind speed and direction
  • Pressure
  • Precipitation
  • Water vapor
  • Temperature
  • Clouds
  • Radiation budget

ISO Topic Categories is the keywords in the ISO 19115 - Geographic Information Metadata.

Science Keywords hosts Global Change Master Directory (GCMD) Keywords which are a hierarchical set of controlled Earth Science vocabularies that help ensure Earth science data, services, and variables are described in a consistent and comprehensive manner and allow for the precise searching of metadata and subsequent retrieval of data, services, and variables.

ECV Keywords hosts a physical, chemical or biological variable or a group of linked variables that critically contributes to the characterization of Earth's climate.

Date Description of Change
2026-06-25 Published and assigned a DOI.