GLOSS Training Workshop Course

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GLOSS Training Workshop Course Japan
Meteorological Agency May 15-26, 2006
Sea Level Data Processing with SLPR2 5.
Filtering of Hourly Data
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Filtering Create Daily and Monthly Values
Manual Section 6
Method
Removes primary tidal energy (S1, M1, S2,
M2,) 119-point (5-day) Convolution Filter
centered on noon Handles Gaps -demeans data
over 5-day window -assigns zero to missing
data -averages across gap -performs
final calculation Amplitude Response of Filter
95, 50, and 5 at 124, 60, and 40 hours
-Nyquist Frequency at 48 hours thus, minimal
aliaising from tides -Primary tidal energy
has response of 0.1 (negligible)
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Filtering Create Daily and Monthly Values
Manual Section 6
Procedure
Step 1. Ensure each year of hourly data has 12
months of data or flags If not, use
\slpr2\util\FILLVM.EXE to make blocks of months
of missing data flags Step 2. Run
\slpr2\filt\FILTHR.EXE Step 3. Plot daily and
monthly data with \slpr2\plot\PDALL.EXE
and PMALL.EXE
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Analyzing Daily and Monthly Values
Example Puerto Armuelles, Panama
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Analyzing Daily and Monthly Values
Manual Section 6.3
Calculate difference with neighboring station
\slpr2\filt\DIFFDAY.EXE and DIFFMON.EXE Plot
(\slpr2\PDALL.EXE and PMALL.EXE) - enter
diff for start year
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Difference Puerto Armuelles, Panama minus
Manzanillo, Mexico
suspicious
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Daily Data Plot for 1999, Puerto Armuelles
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Difference Puerto Armuelles, Panama minus
Manzanillo, Mexico
1999
Daily and Monthly Plots useful to identify
reference level shifts
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• HOTS ASSIGNMENT
• Filter years of hourly files into daily and
  monthly values
• Plot daily and monthly values
• Do this for at least two stations
• Run the difference program for daily and monthly
  data
• 5. Plot the difference files