Challenge ID |
C-CORE_OFF1.2 |
Title |
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Challenge originator: interviewed company |
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General Description |
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What data/products do you use? |
Historical wind wave heights, swell wave heights, and significant wave heights are available in the form of surface-based observations, as reported from ships and buoys, via ICOADS and NOAA (NDBC).
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When do you use this kind of dataset? |
Historical wavedata (Hs, Tp, Tz etc.) are used in all phases throughout the O&G cycle, except strictly operational tasks.
Finally wave data are important to design of structures that can withstand the local conditions and take into account the risk of the extreme situations of the area. |
What are your actual limitations and do you have a work around? |
For more superficial analysis, first looks etc. an estimate is often sufficient and the quality of the data set is not as critical as for design studies. The latter requires long time series (for instance preferably more than 1/4 of the extreme calculated - i.e. 25 yrs for 100 year extreme) and high resolution in time and space in order to catch vigorous short-lived and small scale local phenomena. Data of sufficient quality can be hard to come by in coastal and remote/less developed areas and rougher modeled data, estimates and approximations will be used. Sometimes calibration of modeled data to shorter observed time series has to be made.
Update frequency:
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Needs and expectations on EO data |
EO is used for this today, but resolution, update frequency, length of data series and quality is not sufficient for instance design studies. It is used as input in regional reanalysis and hindcast.
EO data that can improve modeled re-analyses.
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Challenge classification |
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Pre license |
3 |
Exp. |
4 |
Dev. |
4 |
Prod. |
3 |
Decom. |
3 |
Geographic context/ restrictions |
Applies to all six areas of interest, except for the cautionary notes about tropical cyclones, which only applies to South China Sea, West of Ireland, and Myanmar.
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Topographic classification / Offshore classification |
Ocean |
Activity impacted/concerned |
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Technology Urgency |
Short term (2-5 years) |
Information requirements |
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Update frequency |
Daily or weekly, since historical data are often needed to assess recent events. For some parameters and data sets, monthly is still sufficient.
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Temporal resolution |
Data should be at least 1-3 hourly depending on area and phenomena needed to be resolved.
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Spatial resolution |
Around 4 km, maybe less in coastal areas.
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Data quality |
The selected sources in this document are selected because they are known to have sufficient quality (after some work-around/adaptations). In general separate in-depth verification studies has to be made for each source planned to be used for analysis, and the analysis has to be repeated for each geographical area (since sources might be of sufficient quality in one area but not another).
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Data Coverage and extent |
Regional. |
Example format |
ERA-Interim: grib and netCDF
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Timeliness |
Normally needed urgently, possibly before assessing, planning, or exploring a new field. Hence the data source used for analysis needs to be frequently updated to avoid unnecessary waiting. Daily, weekly or monthly updates of data sets are sufficient, depending on the analysis required. |
Existing standards |
Multiple paragraphs in DNV-RP-C205, OTO 2001/010, ISO-19001-1, NORSOK-N-003e2, NORSOK-N-006u1, and DNV-OS-J001 contain extensive references to the standard measures of the means and extremes of waves, including the recommended approximations and calculations of return periods and probabilities of exceedance. The DNV series acknowledges that the procedures may not be applicable beyond the area of interest that it was tailored for. |