ENSO Composite Plots: Details and Directions

• Output Form
  Choose one of the 4 types. For the last 3 options, two plots will be shown next to each other. You should choose the region desired and the variable for all plots. For the single plot, you will also need to choose, event, type and season. For El Niño vs La Niña, just type and season. For summer vs winter, event and type.
• Region
  A global plot or just over the United States (235E to 285E and 20N to 65N).
• Event
  ENSO Events are defined using SST for the Nino 3.4 region and SOI. Events are chosen that have a consistent signal throughout the entire season. Years that define the events are listed on the main page.
• Season
  Winter is defined from November to March. Summer for May through September. Years given are the year of the last month of the season.
• Type
  Means and Anomalies. Anomalies are calculated relative to the 1981-2010 time period for the NCEP data and the 1971-2000 time-period for the climate division data.
• Variable

  Surface Air Temperature

  Temperature at the lowest model level (.995 sigma)

  Sea Level Pressure

  Climate Division Temperature

  Surface temperature averaged over US state climate divisions.

  Climate Division Precipitation

  Precipitation averaged over US state climate divisions.

  Surface Zonal Wind

  East to west winds at the lowest model level (.995 sigma). Positive values indicate winds from the west.

  Surface Meridional Wind

  North to south winds at the lowest model level (.995 sigma). Positive values indicate winds from the south.

  Precipitation Rate

  mm/day

  200mb Zonal Wind

  East to west winds at 200mb.

  500mb Geopotential Height

  Height in meters of the 500mb surface.

  700mb Omega

  Vertical velocity at 700mb. Positive values are downward.

  SST

  Sea Surface Temperature (plus ice temperatures).

Data: