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Seasonal Precipitation and Standardized Velocity Potential Anomalies and Divergent Wind

This is a map of seasonal (3-month) CAMS-OPI precipitation anomaly from the long-term mean, and seasonal-average standardized velocity potential anomaly (select from 925 hPa and 200 hPa pressure levels), and the divergent part of the wind (vectors) over the tropical Indian and Pacific Oceans.

The climatological base period used to calculate the precipitation anomalies is 1979-2000. Areas shaded in brown represent negative precipitation anomalies, and areas shaded in green represent positive precipitation anomalies. Blue contours represent the seasonal standardized velocity potential anomalies; solid lines are positive anomalies from the 1981-2010 mean, and dashed lines are negative anomalies. The standardized velocity potential anomalies are contoured at an interval of 0.5 s.d. The blue vectors indicate the gradient of the seasonal velocity potential anomalies, representing the divergent part of the wind. The magnitude of the gradient is indicated by the vector length.

Dataset Documentation

Monthly Precipitation Anomaly Data

Data
CPC CAMS_OPI v0208 monthly precipitation anomaly values at 2.5° lat/lon resolution
Data Source
NOAA National Centers for Environmental Prediction (NCEP) Climate Prediction Center (CPC), CAMS_OPI
Analysis
Seasonal (three-month) average of monthly precipitation anomalies using 1979-2000 base period over the tropical Pacific and Indian Oceans at 925 and 200 hPa

Velocity Potential Data

Data
NCEP-NCAR Reanalysis monthly velocity potential at 925 and 200 hPa on a 2.5° lat/lon grid
Data Source
NOAA National Centers for Environmental Prediction (NCEP) (NCEP/NCAR Reanalysis)
Analysis
Three-month average of standardized monthly velocity potential anomalies (1981-2010 base period) over the tropical Pacific and Indian Oceans at 925 and 200 hPa, and the gradient of the velocity potential anomaly field

Dataset

Access the dataset used to create this map.

Helpdesk

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