RB-09-02 Tsunami Readme File
  
Ship:                   NOAA research vessel Ronald H. Brown 
Cruise Start:           Charleston, SC, May 11, 2009 
Cruise End:             Charleston, SC, May 25, 2009 
Chief Scientists:       Uri Ten Brink 
System Operator:        Jonathan Shannahoff  

Method: 
The system was built by General Oceanics (GO) and is described in  
Pierrot, et al. (2009).

The three standard gases come from CMDL in Boulder and are directly 
traceable to the WMO scale.  

Sampling Cycle: 
The system runs on an cycle during which 4 standard gases, 5 air  
samples from the bow tower and 50 surface water samples (from the  
equilibrator head space) are analyzed on the following schedule:   

1. Zero and span of Licor 
2. Four standard gases 
3. Five air samples 
4. Fifty equilibrator headspace gas samples 
5. Repeat steps 2 - 4 nine more times 
6. Restart from step 1  

Standards:  CA6709: 284.75 ppm, CA2813: 363.24 ppm, CA9721: 423.57 ppm, 
CA7931: 545.88 ppm.  

Units: 
All xCO2 values are reported in parts per million (ppm) and fCO2  
values are reported in microatmospheres (uatm) assuming 100 %  
humidity at the equilibrator temperature.  

Notes: 1. Any values outside the range of the standards (284.75 to 545.88 
ppm) have been flagged as 3 and should be considered approximate 
(within 5 ppm).  While individual data points above 545 or below 285 
may not be accurate, the general trends should be indicative of the 
seawater chemistry. 

2. Salinity readings from the ship's TSG were bad.  Readings from the 
Seabird Micro TSG connected to the analytical system were used instead. 

3. An offset of 2.35 minutes was applied to SST data from the ship's 
computer system. 

4. There were over 100 elevated air values that have been removed 
from the data set.  These values are likely accurate and caused by 
land-based sources of CO2.  However, they are not  representative 
of typical marine boundary layer concentrations. For those who are 
interested in these values, email robert.castle@noaa.gov and they 
can be provided.  

For questions or comments contact: 
Bob Castle 
4301 Rickenbacker Causeway 
Miami, FL 33149 
305-361-4418 
robert.castle@noaa.gov 

Pierrot, D., C. Neil, K. Sullivan, R. Castle, R. Wanninkhof, H. Lueger, 
T. Johannson, A. Olsen, R. A. Feely, and C. E. Cosca (2009),
Recommendations for autonomous underway pCO2 measuring systems 
and data reduction routines, Deep-Sea Res II, 56, 512-522.