Frequently Asked Questions

FAQs

Here you will find some frequently asked questions. If your question was not addressed here or anywhere else on our website, then please ask for help in our web forum (http://forum.hycom.org) or search our wiki (http://wiki.hycom.org).

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Yes. We are aware that some days in the GOFS 3.1 Global Reanalysis (GLBv0.08/expt_53.X) with Ice Fields have missing data. We will not be filling in these data gaps. The following times are known to be missing from the Global Reanalysis Ice Fields.

GOFS 3.1 and 3.5 topography files use 30 arc-second GEBCO as the base that was released in 2009.

Yes. We are aware that some days in the HYCOM + NCODA Gulf of Mexico 1/25° Analysis (GOMu0.04/expt_90.1m000) are missing data. We will not be filling in these data gaps. There are times when the daily forecasts do not run due to computer issues, problematic input data sources, or other unforeseen problems. The following times are known to be missing:

Yes. We are aware that some days in the GOFS 3.1 Global Analysis (GLBv0.08|GLBy0.08) are missing data. We will not be filling in these data gaps. There are times when the daily Global Ocean Forecast System does not run due to computer issues, problematic input data sources, or other unforeseen problems. The following times are known to be missing from the Global Reanalysis.

GLBy0.08 grid is 0.08 deg lon x 0.04 deg lat that covers 80 S to 90 N.

GLBv0.08 grid is 0.08 deg lon x 0.08 deg lat between 40S - 40 N. Poleward of 40 S / 40 N, the grid is 0.08 deg lon x 0.04 deg lat. It spans 80 S to 90 N.

GLBu0.08 grid is 0.08 deg lon x 0.08 deg lat that covers 80 S to 80 N.

NOTES:

(2018-Dec-08): GLBu grid outputs have been turned off.

(2018-Dec-13): GOFS 3.1 currently makes both GLBv and GLBy files, with the intent that GLBv will be turned off once FNMOC makes sure all downstream products can deal with GLBy grid files.

Yes. We are aware that some days in the GOFS 3.1 Global Reanalysis (GLBv0.08/expt_53.X) are missing data. We will not be filling in these data gaps. There are times when the daily Global Ocean Forecast System does not run due to computer issues, problematic input data sources, or other unforeseen problems. The following times are known to be missing from the Global Reanalysis.

Global Ocean Forecasting System (GOFS)

Yes. We are aware that some days in the GLBu0.08/expt_9x.x experiments are missing NetCDF data. Without interpolation, there is no way for us to fill in these data gaps. There are times when the daily Global Ocean Forecast System does not run due to computer issues, problematic input data sources, or other unforeseen problems. The following times/days are known to be missing from GLBu0.08/expt_91.1 (see GLBu0.08 Documentation here):

Yes. We are aware that some days in the Global Reanalysis (GLBu0.08/expt_19.x) are missing data. We will not be filling in these data gaps. There are times when the daily Global Ocean Forecast System does not run due to computer issues, problematic input data sources, or other unforeseen problems. The following times are known to be missing from the Global Reanalysis.

NRL creates GIF movies and snapshots for the following HYCOM model runs:

Movies and snapshots of the 1/12° Global HYCOM

New experiment numbers correspond to improvements in either the code or data assimilation.

The global hycom grid is rectilinear from j=1 to j=2172, and you can check this by confirming that the minval and maxval of plat(1:4500,j) are identical there. The grid is curvilinear (bi-polar patch) from j=2173 to j=3298. Note that the j=3298 row is a permuted copy of j=3297 (because of the way the tripole grid is implemented in HYCOM), so you can discard j=3298.

Yes. We are aware that some days (early on in the GLBa0.08 model runs) are missing data. Without interpolation there is no way for us to fill in these data gaps. There are times when the daily Global Ocean Forecast System does not run due to computer issues, problematic input data sources, or other unforeseen problems. The following days are known to be missing data from the GLBa0.08 model, spanning multiple experiments (see GLBa0.08 Documentation here):

Here is the breakdown of the GLBa0.08 data files for a 00Z snapshot (1 day):

Currently running on a Cray XT5 (at the Navy DSRC), the HYCOM GLBa0.08 with data assimilation takes about 2 wall hours per model day using 624 cores (78 nodes, each holding two AMD Barcellona 4-core chips).

No. This is a demonstration product from the HYCOM Consortium and is provided as is. HYCOM Consortium does not warrant or suggest that this data is fit for any particular purpose. Further, neither COAPS nor the HYCOM consortium guarantees availability, service updates, or timely data delivery.

Go to the GoM (GOMu0.04) model information page here.

Go to the GOFS 3.1 (GLBy0.08) model information page here.

Click Account Request in the left-hand menu, or click here.

Disclaimer

This is a demonstration product from the HYCOM Consortium and is provided as is. HYCOM Consortium does not warrant or suggest that this data is fit for any particular purpose. Further, neither COAPS nor HYCOM consortium guarantees availability, service updates, or timely data delivery.

All hycom data provided is UNCLASSIFIED. DoD DISTRIBUTION A. Approved for Public Release; Distribution Unlimited.

	GOFS 3.1	GOFS 3.0

HYCOM source code	2.2.99DHMTi	2.2.19

Equation of state	17-term	7-term

Layers	41, nine additional layers near the surface, top 14 layers are always sigma-z so that water shallower than 84 m is always in fixed coordinates	32

Frequently Asked Questions

FAQs

Forum FAQs and README.

Did you know there are missing days in the GOFS 3.1 Global Reanalysis Ice Fields?

What bathymetry is used for hycom model runs?

Did you know there are missing days in the Gulf of Mexico Analysis?

Did you know there are missing days in the GOFS 3.1 Global Analysis?

What is the difference in the GLBy/GLBv/GLBu grids?

NOTES:

Did you know there are missing days in the GOFS 3.1 Global Reanalysis?

What are the major differences between GOFS 3.1 and GOFS 3.0?

Did you know there are days in GLBu0.08 Analysis missing data?

Did you know there are missing days in the GOFS 3.0 Global Reanalysis?

Where can I find the pretty pictures and animations of HYCOM data?

What causes a change in experiment number?

Explain the hycom grid?

Did you know there are days missing data?

How much storage is required for the HYCOM data in netCDF format?

How much CPU time is required to produce the HYCOM GLBa0.08 data?

Can I rely on data to be updated daily?

How can I access the latest Gulf of Mexico forecasts?

How can I access the latest Global ocean forecasts?

How do I request a HYCOM account?

Disclaimer