forum.HYCOM.org is intended to facilitate the following:

• Share information on the use of HYCOM data
• Connect our users with the "experts" that develop and generate the model data

Please request a HYCOM.org account here (https://hycom.org/account-request) or subscribe using your own Google ID for posting to this forum.

If you are a HYCOM beginner, please check/read the following documentation before posting to the forum.
HYCOM Documentation

• Please provide the Model & Experiment number (e.g., GLBy0.08/expt_93.0).
• Also include the *full URL* of the dataset (i.e., access method) in your post.
• Do not subset more than 1 day at a time using ncss.hycom.org
• Do not use more than 1 concurrent connection per IP address when downloading data from ncss.hycom.org
• Do not use more than 10 concurrent connections per IP address when downloading data from any hycom.org service
• Make sure your email Subject matches the context of your message Body.
• If you have multiple questions, please break them up into separate posts (threads).
• Reduce/Remove lengthy email signatures when posting to the forum.
• THREDDS servers update/restart daily between 2:00 AM - 3:00 AM, and 12:00 PM - 1:00 PM EST/EDT.
  ** Please avoid requesting data during this maintenance window, else you are likely to get an error **

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:

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)

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

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):

Read more...

 

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

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.

Read more...

 

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

NRL creates GIF movies and snapshots for the following HYCOM model runs: Movies and snapshots of the 1/12° Global HYCOM

 

What causes a change in experiment number?

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

 

Explain the hycom grid?

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.

 

Did you know there are days missing data?

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):

Read more...

 

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

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

Read more...

 

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

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).

 

Can I rely on data to be updated on a daily basis?

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 HYCOM consortium guarantee availability, service updates or timely data delivery.

 

How can I access the latest Gulf of Mexico forecasts?

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

 

How can I access the latest Global ocean forecasts?

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

 

How do I request a HYCOM account?

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