Correcting Surface Pressure to Sea Level

[Mark Hess]

I tried to access the GrADS User archives for this answer, but the page would not allow me to search.Perhaps someone can point me in the right direction.  When plotting surface pressure (isobars)  from the GFS GRIB files, my data show very low pressure values over land.  While not sure, I am guessing this is because the data need to be corrected to sea level.  Is this correct? If so, can someone provide a resource which explains how to 'correct' the data? If I am incorrect, Can you please explain what I am doing wrong? Thanks.

Mark
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://gradsusr.org/pipermail/gradsusr/attachments/20100311/f41b8acc/attachment.html