Station details:
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Code: PTO
Latitude:  41.13861
Longitude:   -8.60222
Elevation:    88.0
Depth: 
Name: Porto
Region: Portugal
Status: 

      

        
     
    
   
   

    

     

      
Arrival picks statistics
     
     

      

      

     
     

      
Travel Time Analysis
     
     

      

      

     
     

      
On the top graph every dot represents the median residual for one month of data. The green line is the overall median; the orange line shows the standard deviation (smad) based on the median absolute deviation (mad), whilst the red line shows twice the standard deviation (2 * smad).
The bottom graph shows the number of residuals for each month. The red columns show the number of residuals whose median (for that month) is outside two standard deviations from the overall median (2 * smad).
Red dots indicate a possible clock error.
     
     

      
Travel time residuals
     
     

      

      

      

     
     

      
Amplitude analysis
     
     

      

     
     

      
 On the top graph every dot represents the median value for that month of data.
The green line is the overall median; the orange line shows the standard deviation (smad) based on the median absolute deviation (mad), whilst the red line (if present) shows twice the standard deviation (2 * smad).
The bottom graph shows the number of observations for each month. Any red columns show those observations whose monthly median value is greater than twice the standard deviation (2 * smad) from the overall (running) median (shown in the top graph by red dots).

Red dots indicate a possible calibration error.
     
    
   
 

Station comments:
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Checked against station bulletin
XC1R4-MSF-WWV
1912-1997
WWSS opened 19630330

Data at the ISC for 65 years between 1931 and 2024.