Winds around the world

Goal: characterize the winds available around the world.

First we need to construct our grid:

The horizontal, latitude-longitude grid ranges from +70 to -70 deg in latitude and from 0 to 357.5E deg in longitude, producing a grid that has dimensions of 57 x 144 points.

In matlab, this is:

[cells/degree northern_latitude_limit western_longitude_limit]

These data were produced from the “NCEP/NCAR Reanalysis”: are available at six-hour intervals, from January 1, 1948 to the present, and it is this 6-hour data that was used as the basis for this work.

Spatially, the delivered data values are given at points in a three-dimensional, global system using a 2.5 x 2.5 deg grid of latitude-longitude and altitudes that are specified by atmospheric pressure.

Above each point in this grid, horizontal wind information is delivered at 4 pressure levels: 50 mb, 70 mb, 100 mb, and 150 mb. If we assume a standard day, this corresponds to: 67,726 60,504 53,083 44,647 feet. At each grid point and pressure altitude, the horizontal wind vectors have been sorted into 12 directional bins.

Cells per degree = 2.5
Degrees per cell = 0.4

– how linear is the wind change with altitude?
– where are winds high?

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