
JRA-25 is a second generation reanalysis product. The model and data assimilation are from the operational system in April 2004. It was the first reanalysis to assimilate wind profiles around tropical cyclones deduced from best-track data, resulting in improved tropical cyclone analysis in a global context. In addition, low-level (stratus) cloud decks along the western subtropical coasts of continents are also better simulated, improving radiation budgets in these regions. A primary goal of JRA-25 is to provide a consistent and high-quality reanalysis dataset for climate research, monitoring, and operational forecasts, especially by improving the coverage and quality of analysis in the Asian region. Note: JRA-25 has been superseded by the JRA-55 reanalysis, a 3rd generation product.
Key Strengths:
- Long time series of the global precipitation is the best among the other second generation reanalyses
- Assimilate wind profiles around tropical cyclones
- Low-level cloud along the subtropical western coast of continents is well simulated
Key Limitations:
- Does not account for satellite biases. Can affect trend; large temperature biases in stratosphere
- CO2 held constant for all 25 years
- Cold bias in lower stratosphere; Dry bias over Amazon
Years of Record
Formats
Timestep
Data Time Period Extended?
Domain
Spatial Resolution
Ocean or Land
Missing Data Flag
Data Assimilation Method
Model Resolution used to create reanlaysis
Model Vintage (reanalysis)
Data Access: Please Cite data sources, following the data providers' instructions.
Usage Restrictions
- Onogi, K., & others, 2007: The JRA-25 Reanalysis. J. Met. Soc. Jap., 85(3), 369-432.