Tell me more ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.
up vote 0 down vote favorite

What is the implicit geodetic model used by common numerical weather prediction products? WGS84? NAVD88?

For example, NOAA's Rapid Refresh (RAP), North America Mesoscale (NAM), and Global Forecast System (GFS) models all provide the variable geopotential-height as an output. This implies some model for mean-sea-level. What model?

I'm ultimately trying to express the geopotential-height as geometric-height in WGS84.

Edit

To clarify, does RUC/RAP/GFS use WGS84 as its horizontal reference system with EGM96 (or other) as its geoid definition?

share|improve this question
1  
Welcome chriswynnyk. If you read the FAQ you'll see that computational questions as such are not part of our remit. Instead you should use the Scientific Computation site for such question. I'm not going to close this because I am not positive which bin the question goes in. If it belongs on SciComp, we can move it for you so you don't need to re-post. Would you like to clarify? – dmckee♦ Mar 14 at 14:37
I'm looking for the feedback from a meteorologist or physical science expert who is knowledgeable in geodetic and atmospheric modeling. The terms "geodetic" and "atmospheric" had many more hits here than in SciComp, so I think I'm in the right place. – chriswynnyk Mar 14 at 14:46
Perhaps if there are no responses in a few days, it would make sense to try the other forum as well. – chriswynnyk Mar 14 at 14:49
2  
Just because your key terms had more hits here doesn't necessarily make this the right place for the question. This isn't a meteorology site - we do host questions about the physics underlying meteorology, but that's about it. Now, your question does involve geodesy, which is related to physics, but it's really asking about meteorological models, which I think puts it in scope for a computational site or a meteorology site (which doesn't exist in the SE network), not here. It's a close call, though, so we'll see what other people think. – David Zaslavsky♦ Mar 14 at 17:21
@chriswynnyk You may want to have a look at gis.stackexchange.com - I can't promise this is within their scope, but they may have more stuff along these lines. – Chris White Apr 6 at 20:57

1 Answer

up vote 0 down vote

WGS84 is the model, and provides a standard coordinate frame for the Earth, a standard spheroidal reference surface (the datum or reference ellipsoid) for raw altitude data, and a gravitational equipotential surface (the geoid) that defines the nominal sea level. The geoid is the equipotential surface of the Earth's gravity field which best fits, in a least squares sense, global mean sea level Take a look at the figures here for more understanding What is the geoid?.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.