# file: smo_CCl4_MM.dat # # Atmospheric measurements of CCl4 (Carbon Tetrachloride, CT) # # Measurements are from the NOAA/ESRL/GMD/HATS flask program # (http://www.esrl.noaa.gov/gmd/hats/flask/flasks.html). # Instrument ID: Otto # # Location: SMO -- Tutuila, Samoa -- 14.25 S, 170.56 W, 42 m Elev. # See http://www.esrl.noaa.gov/gmd/dv/site/site_table.html#hats_flask for # more information about flask sampling sites. # # The data reported are from samples collected approximately once per week in # matching, concurrent, flask pairs and later analyzed on a gas chromatograph # with electron capture detection (GC-ECD) located in Boulder, Colorado, USA. # This system uses two standard reference gases for calibration and has been # in operation since very early in 1995. # # CCl4 loss during storage in stainless-steel canisters arises most commonly at # high-latitude and/or high-altitude sites where the air is dry (i.e. ALT, BRW, # MLO, NWR, and SPO -- especially in winter). Extra efforts have been made to # flag samples suspected of suffering from this known artifact, thereby barring # them from inclusion in monthly mean estimates. The user is cautioned, # however, that small biases to the low side may nevertheless remain. # # These data represent monthly mean estimates computed using those data marked # with a 0 in flag column 7 of the companion file named "smo_CCl4_All.dat". With # flask samples collected only weekly on average, monthly sampling statistics # are poor at best. As a result, the error reported is either the standard # deviation of the mean or a floor single-sample precision estimate. # # PIs: Dr. James W. Elkins, Dr. Bradley D. Hall, # Debra J. Mondeel, J. David Nance # # National Oceanic and Atmospheric Administration (NOAA) # Earth System Research Laboratory (ESRL) # 325 Broadway, R/GMD1 # Boulder, CO 80305-3328 # # Email: James.W.Elkins@noaa.gov; Bradley.Hall@noaa.gov # Phone: (303) 497-6224 (303) 497-7011 # # Email: Debra.J.Mondeel@noaa.gov; David.Nance@noaa.gov # Phone: (303) 497-6013 (303) 497-7002 # # Fax: (303) 497-6290 # # Data use policy: # If you use this data in a publication or report, we would appreciate that you # contact the principal investigators (PIs) first and discuss your interests. # The PIs can discuss the quality of the data and any potential problems with # its analysis. Please contact the PIs for more information. The data should # be cited in presentations or publications along the following lines: Carbon Tetrachloride # data from the NOAA/ESRL halocarbons flask program. # # Calibration scale: NOAA 2008 # See http://www.esrl.noaa.gov/gmd/ccl/scales.html for more information about # calibration scales. # # Units: ppt # # Missing value: "nan" # # Data Columns: # yr Year # mon Month # m Monthly mean concentration of CCl4 in ppt # sd Standard deviation of the mean (or single-sample precision value) # n Number of samples # CCl4ottoSMOyr CCl4ottoSMOmon CCl4ottoSMOm CCl4ottoSMOsd CCl4ottoSMOn 1995 1 nan nan 0 1995 2 nan nan 0 1995 3 nan nan 0 1995 4 nan nan 0 1995 5 nan nan 0 1995 6 nan nan 0 1995 7 nan nan 0 1995 8 nan nan 0 1995 9 103.815 0.622 2 1995 10 103.832 0.285 2 1995 11 104.210 0.396 1 1995 12 104.730 0.380 1 1996 1 103.920 0.359 2 1996 2 103.290 0.574 1 1996 3 103.940 0.293 1 1996 4 103.445 0.337 3 1996 5 103.395 0.534 4 1996 6 103.759 0.449 5 1996 7 103.672 0.398 2 1996 8 103.660 0.321 2 1996 9 103.650 0.858 1 1996 10 103.870 0.710 1 1996 11 102.556 0.567 3 1996 12 103.472 0.475 2 1997 1 103.361 0.390 3 1997 2 103.119 0.355 2 1997 3 102.917 0.785 2 1997 4 102.838 0.336 2 1997 5 102.320 0.308 1 1997 6 102.807 0.347 5 1997 7 102.576 0.391 3 1997 8 102.222 0.598 4 1997 9 102.288 0.281 2 1997 10 101.480 0.241 1 1997 11 102.480 0.422 3 1997 12 102.242 0.625 3 1998 1 102.386 0.460 2 1998 2 101.814 0.534 2 1998 3 101.337 0.261 3 1998 4 101.200 0.279 2 1998 5 101.793 0.200 4 1998 6 101.225 0.488 3 1998 7 101.177 0.401 3 1998 8 100.899 0.199 3 1998 9 101.116 0.139 2 1998 10 101.230 0.272 1 1998 11 101.714 0.297 2 1998 12 101.578 0.235 2 1999 1 101.676 0.452 4 1999 2 101.838 0.216 5 1999 3 101.633 0.368 2 1999 4 101.629 0.139 2 1999 5 100.291 0.508 3 1999 6 100.953 0.692 4 1999 7 100.425 0.325 5 1999 8 100.684 0.177 4 1999 9 100.293 0.249 3 1999 10 100.248 0.346 4 1999 11 100.234 0.208 4 1999 12 100.478 0.813 4 2000 1 100.884 0.267 4 2000 2 100.386 0.284 3 2000 3 99.841 0.540 3 2000 4 99.674 0.429 3 2000 5 99.243 0.389 3 2000 6 98.268 0.374 4 2000 7 98.838 0.362 4 2000 8 98.711 0.569 4 2000 9 98.600 0.337 4 2000 10 98.743 0.248 4 2000 11 99.201 0.673 4 2000 12 99.104 0.339 2 2001 1 99.507 0.542 5 2001 2 98.372 0.222 3 2001 3 98.969 0.238 4 2001 4 98.149 0.594 2 2001 5 98.432 0.162 5 2001 6 98.270 0.188 4 2001 7 97.800 0.509 3 2001 8 97.954 0.503 5 2001 9 97.506 0.513 4 2001 10 97.943 0.512 4 2001 11 97.631 0.299 3 2001 12 97.147 0.404 3 2002 1 97.690 0.213 7 2002 2 98.133 0.231 4 2002 3 97.361 0.369 7 2002 4 96.811 0.216 6 2002 5 96.531 0.455 6 2002 6 96.569 0.326 7 2002 7 96.520 0.257 4 2002 8 96.436 0.309 5 2002 9 95.822 0.315 5 2002 10 96.545 0.490 5 2002 11 96.654 0.659 5 2002 12 96.402 0.271 3 2003 1 96.138 0.323 7 2003 2 95.549 0.613 4 2003 3 96.083 0.173 6 2003 4 95.840 0.462 6 2003 5 95.717 0.412 7 2003 6 95.280 0.255 6 2003 7 95.223 0.298 6 2003 8 95.267 0.349 5 2003 9 95.084 0.199 6 2003 10 94.982 0.163 5 2003 11 95.032 0.485 5 2003 12 95.114 0.371 4 2004 1 94.505 1.039 2 2004 2 95.262 0.270 5 2004 3 95.094 0.316 5 2004 4 95.092 0.271 5 2004 5 94.791 0.216 5 2004 6 94.602 0.334 6 2004 7 94.409 0.390 4 2004 8 94.751 0.438 4 2004 9 94.315 0.175 6 2004 10 94.034 0.363 4 2004 11 94.174 0.313 5 2004 12 94.286 0.248 5 2005 1 94.433 0.389 5 2005 2 94.280 0.232 5 2005 3 94.552 0.504 6 2005 4 94.369 0.290 4 2005 5 93.668 0.234 5 2005 6 93.853 0.239 6 2005 7 93.334 0.227 5 2005 8 93.454 0.325 6 2005 9 93.452 0.197 5 2005 10 93.373 0.143 5 2005 11 93.583 0.298 3 2005 12 93.720 0.359 1 2006 1 93.630 0.230 1 2006 2 93.374 0.207 2 2006 3 93.442 0.302 4 2006 4 93.332 0.566 2 2006 5 92.980 0.571 5 2006 6 92.703 0.172 4 2006 7 92.478 0.216 4 2006 8 92.422 0.179 7 2006 9 92.370 0.197 4 2006 10 92.192 0.238 4 2006 11 92.387 0.214 5 2006 12 92.494 0.272 4 2007 1 92.105 0.342 5 2007 2 92.589 0.252 5 2007 3 92.494 0.292 5 2007 4 92.098 0.437 5 2007 5 92.010 0.159 4 2007 6 91.561 0.383 4 2007 7 91.795 0.365 4 2007 8 91.535 0.194 6 2007 9 91.275 0.204 4 2007 10 91.227 0.241 6 2007 11 91.363 0.208 5 2007 12 91.101 0.290 5 2008 1 91.422 0.206 5 2008 2 91.232 0.168 5 2008 3 91.078 0.341 5 2008 4 90.737 0.144 6 2008 5 90.868 0.241 5 2008 6 90.271 0.398 4 2008 7 89.751 0.197 6 2008 8 89.717 0.181 5 2008 9 89.488 0.215 4 2008 10 89.573 0.159 6 2008 11 89.604 0.189 5 2008 12 89.486 0.227 4 2009 1 89.826 0.337 5 2009 2 89.569 0.265 4 2009 3 89.407 0.251 5 2009 4 89.179 0.384 5 2009 5 88.881 0.209 5 2009 6 88.515 0.293 4 2009 7 88.434 0.303 9 2009 8 88.455 0.319 6 2009 9 88.844 0.364 9 2009 10 88.663 0.188 3 2009 11 88.738 0.335 6 2009 12 88.622 0.289 6 2010 1 88.841 0.469 3 2010 2 88.049 0.242 2 2010 3 88.488 0.234 5 2010 4 nan nan 0 2010 5 nan nan 0 2010 6 87.750 0.268 1 2010 7 87.902 0.168 4 2010 8 88.150 0.134 4 2010 9 87.607 0.390 5 2010 10 87.478 0.231 2 2010 11 87.550 0.275 1 2010 12 87.491 0.298 4 2011 1 87.630 0.231 3 2011 2 87.479 0.410 2 2011 3 87.607 0.215 5 2011 4 86.659 0.241 2 2011 5 86.714 0.185 4 2011 6 86.400 0.242 3 2011 7 86.320 0.226 3 2011 8 86.288 0.228 3 2011 9 86.202 0.183 6 2011 10 86.007 0.212 5 2011 11 86.242 0.193 3 2011 12 86.245 0.516 2 2012 1 85.810 0.449 1 2012 2 85.975 0.358 5 2012 3 85.693 0.340 3 2012 4 85.496 0.296 4 2012 5 85.439 0.391 2 2012 6 85.609 0.370 4 2012 7 84.942 0.425 4 2012 8 85.239 0.302 4 2012 9 85.065 0.536 4 2012 10 84.891 0.251 5 2012 11 84.913 0.322 4 2012 12 84.726 0.294 4 2013 1 84.864 0.507 5 2013 2 84.770 0.312 5 2013 3 84.521 0.321 5 2013 4 84.962 0.229 3 2013 5 84.467 0.362 5 2013 6 84.392 0.285 4 2013 7 84.219 0.258 2 2013 8 84.502 0.747 3 2013 9 83.990 1.421 1 2013 10 nan nan 0 2013 11 83.865 0.352 4 2013 12 84.235 0.242 4 2014 1 84.167 0.196 5 2014 2 84.260 0.241 1 2014 3 nan nan 0 2014 4 nan nan 0 2014 5 83.169 0.457 2 2014 6 83.171 0.345 3 2014 7 82.939 0.222 5 2014 8 82.624 0.482 4 2014 9 82.519 0.315 5 2014 10 82.668 0.319 4 2014 11 82.903 0.211 4 2014 12 82.582 0.201 5 2015 1 82.700 0.212 3 2015 2 82.725 0.285 4 2015 3 82.356 0.256 4 2015 4 82.257 0.168 4 2015 5 81.770 0.212 5 2015 6 81.772 0.238 3 2015 7 81.436 0.214 4 2015 8 81.301 0.208 4 2015 9 81.407 0.175 4 2015 10 81.402 0.205 3 2015 11 81.393 0.235 2 2015 12 81.249 0.261 4 2016 1 81.311 0.299 5 2016 2 81.670 0.476 1 2016 3 81.410 0.625 2 2016 4 81.018 0.387 4 2016 5 81.130 0.308 2 2016 6 81.228 0.376 4 2016 7 80.973 0.377 4 2016 8 80.777 0.556 3 2016 9 80.877 0.306 4 2016 10 80.290 0.263 1 2016 11 80.510 0.357 3 2016 12 80.300 0.405 1 2017 1 80.570 0.504 4 2017 2 80.261 0.204 3 2017 3 80.349 0.460 2 2017 4 80.422 0.297 2 2017 5 80.310 0.575 1 2017 6 80.194 0.326 2 2017 7 79.607 0.556 3 2017 8 79.404 0.570 5 2017 9 79.534 0.850 3 2017 10 79.341 0.401 6 2017 11 78.925 0.180 4 2017 12 79.260 0.259 1 2018 1 nan nan 0 2018 2 79.013 0.295 3 2018 3 78.756 0.532 3 2018 4 78.828 0.200 4 2018 5 78.643 0.446 4 2018 6 78.260 0.656 1 2018 7 nan nan 0 2018 8 77.864 0.238 3 2018 9 77.990 0.671 3 2018 10 78.130 0.457 1 2018 11 78.470 0.694 1 2018 12 78.435 0.674 3 2019 1 78.405 0.289 4 2019 2 78.449 0.345 2 2019 3 78.425 0.409 2 2019 4 78.282 0.284 4 2019 5 78.292 0.462 3 2019 6 78.126 0.385 4 2019 7 77.435 0.180 4 2019 8 nan nan 0 2019 9 nan nan 0 2019 10 nan nan 0 2019 11 nan nan 0 2019 12 nan nan 0