9-Band Wave Energy Data Format: de files
As requested by the US Army Corps of Engineers, CDIP reduces the
estimated wave frequency spectra to wave energy (or sea surface
variance) in 9 period bands.
The data files have 12 columns of numbers in the following format.
| Column |
Description |
| 1 |
Date UTC (YYYYMMDDHHMM) |
| 2 |
Significant Wave Height (cm) |
| 3 |
Peak Period BAND |
| 4 |
22+ sec. wave energy (cm**2) |
| 5 |
18-22 sec. wave energy (cm**2) |
| 6 |
16-18 sec. wave energy (cm**2) |
| 7 |
14-16 sec. wave energy (cm**2) |
| 8 |
12-14 sec. wave energy (cm**2) |
| 9 |
10-12 sec. wave energy (cm**2) |
| 10 |
8-10 sec. wave energy (cm**2) |
| 11 |
6-8 sec. wave energy (cm**2) |
| 12 |
2-6 sec. wave energy (cm**2) |
* Note that 9-band data
from directional buoys obtained from CDIP before November 17, 2005 may have
Tp and Dp values that differ from those now reported. This is a result
of change in our processing; for more details, please refer to the
change report.
NOTE: Estimates of wave energy contain a certain amount of statistical
uncertainty. This uncertainty is function of wave frequency bandwidth
not period bandwidth. Therefore, the energy estimates in the 9 period
bands have varying confidence limits. In general, the statistical
uncertainty gets progressively smaller as you go from the longer to
the shorter wave period bands (which encompass increasingly larger
frequency bandwidths).
Sample Data
From the file de03601199801, wave energy at Grays Harbor, Washington
in January 1998. (Header not included in text files.)
UTC Hs Tp ENERGY(CM^2) by BAND PERIOD LIMITS (SECS)
YYYYMMDDHHMM (CM) (SEC) 22+ 22-18 18-16 16-14 14-12 12-10 10-8 8-6 6-2
----------------------------------------------------------------------------------
199801010513 161 11 1 2 11 25 121 415 367 276 391
199801010543 171 11 1 3 9 34 90 644 379 345 362
199801010613 157 11 1 1 4 19 65 607 384 237 330
199801010643 170 11 1 2 10 32 112 576 403 348 322
199801010713 151 11 1 1 3 36 52 390 314 305 310
199801010743 166 11 1 1 5 28 83 677 268 303 334
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