<div class="eI2">Sea Level Pressure in hPa </div>
The surface chart (also known as surface synoptic chart) presents the distribution of 
the atmospheric pressure observed at any given station on the earth's surface 
reduced to sea level.
You can read the positions of the controlling weather features (highs, lows, ridges or 
troughs) from the distribution of the isobars (lines of equal sea level pressure).
The isobars define the pressure field. The pressure field is the dominating player in 
the weather system.
Additionally, this map helps you to identify synoptic-scale waves and gives you a first 
estimate on meso-scale fronts.
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