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Equatorial Pacific 925 hPa Zonal Wind Hovmöller

These are Hovmöller diagrams (Longitude x Time) showing pentad-average, monthly-average, and seasonal-average (3-month) zonal wind and anomalies at 925 hPa, averaged over 5°S to 5°N, for the past year, across the equatorial Pacific Ocean. These analyses may be used to detect changes in the trade winds associated with the development of ENSO conditions. These may also be used to identify, for example, bursts of westerly winds over the equatorial Pacific that may contribute to changes in ocean temperatures that help to trigger or strengthen El Niño conditions.

Observed or anomalous westerlies (positive values) are in shades of yellow and red; observed or anomalous easterlies (negative values) are in shades of blue; weak observed zonal winds or anomalies (values near zero) are in beige. The base period used to calculate the anomalies is 1981-2010. The longitude domain extends from 120°E to 80°W. On this chart the last year is shown, and time increases vertically.

Dataset Documentation

Equatorial Pacific 925 hPa Zonal Wind Hovmöller

Data
NCEP/NCAR Reanalysis daily and monthly zonal wind at 925 hPa on 2.5° lat/lon grid
Data Source
NOAA National Centers for Environmental Prediction (NCEP) (NCEP/NCAR Reanalysis)
Analysis
Equatorial average of five-day average daily, monthly-average, and seasonal-average (3-month) zonal wind and anomalies (1981-2010 base period), displayed as a longitude x time Hovmöller diagram

Dataset

Access the dataset used to create this map.

Helpdesk

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