# file: lef_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: LEF -- Park Falls, Wisconsin -- 45.95 N, 90.27 W, 472 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 "lef_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 # CCl4ottoLEFyr CCl4ottoLEFmon CCl4ottoLEFm CCl4ottoLEFsd CCl4ottoLEFn 1996 1 nan nan 0 1996 2 nan nan 0 1996 3 nan nan 0 1996 4 nan nan 0 1996 5 nan nan 0 1996 6 nan nan 0 1996 7 nan nan 0 1996 8 104.810 0.821 1 1996 9 nan nan 0 1996 10 105.530 0.859 1 1996 11 nan nan 0 1996 12 105.130 0.818 1 1997 1 nan nan 0 1997 2 104.200 0.401 1 1997 3 104.260 0.418 1 1997 4 nan nan 0 1997 5 104.240 0.254 1 1997 6 104.080 0.301 1 1997 7 104.370 0.328 1 1997 8 nan nan 0 1997 9 103.580 0.552 1 1997 10 nan nan 0 1997 11 103.800 0.286 1 1997 12 nan nan 0 1998 1 103.150 0.622 1 1998 2 103.700 0.488 1 1998 3 nan nan 0 1998 4 nan nan 0 1998 5 103.328 0.353 2 1998 6 102.867 0.263 3 1998 7 102.954 1.075 2 1998 8 102.356 0.238 2 1998 9 101.920 0.333 1 1998 10 102.160 0.186 1 1998 11 102.572 0.261 2 1998 12 103.760 0.332 1 1999 1 nan nan 0 1999 2 102.369 0.245 2 1999 3 nan nan 0 1999 4 101.480 0.275 1 1999 5 101.644 0.213 2 1999 6 101.533 0.293 4 1999 7 101.426 0.495 2 1999 8 100.600 0.186 1 1999 9 101.424 0.382 3 1999 10 101.071 0.297 2 1999 11 100.993 0.353 2 1999 12 101.091 0.912 2 2000 1 101.140 0.327 1 2000 2 101.737 0.812 3 2000 3 100.368 0.488 2 2000 4 100.695 0.238 2 2000 5 100.631 0.329 3 2000 6 100.900 0.211 1 2000 7 100.002 0.425 3 2000 8 100.346 0.321 3 2000 9 100.800 0.466 3 2000 10 100.240 0.212 1 2000 11 100.376 0.231 3 2000 12 100.631 0.222 2 2001 1 100.156 0.353 2 2001 2 99.956 0.208 3 2001 3 99.550 0.317 2 2001 4 99.544 0.300 3 2001 5 99.727 0.428 4 2001 6 100.046 0.265 3 2001 7 99.405 0.261 5 2001 8 99.370 0.378 4 2001 9 99.609 0.295 3 2001 10 100.079 0.503 4 2001 11 99.357 0.318 2 2001 12 99.850 0.422 1 2002 1 99.309 0.336 4 2002 2 99.243 0.260 3 2002 3 99.074 0.530 4 2002 4 98.821 0.410 2 2002 5 98.946 0.280 4 2002 6 98.391 0.447 4 2002 7 98.519 0.432 4 2002 8 98.243 0.283 3 2002 9 98.193 0.271 4 2002 10 97.898 0.390 3 2002 11 nan nan 0 2002 12 97.925 0.495 2 2003 1 97.776 0.276 2 2003 2 98.156 0.242 2 2003 3 97.661 0.162 3 2003 4 97.567 0.190 4 2003 5 97.099 0.515 5 2003 6 97.557 0.207 4 2003 7 97.239 0.258 4 2003 8 97.168 0.404 4 2003 9 96.769 0.510 3 2003 10 96.737 0.180 2 2003 11 96.335 0.199 2 2003 12 96.977 0.157 2 2004 1 96.371 0.354 3 2004 2 96.807 0.206 2 2004 3 96.855 0.341 3 2004 4 96.353 0.332 2 2004 5 96.651 0.203 3 2004 6 96.296 0.169 4 2004 7 96.158 0.228 4 2004 8 96.186 0.408 3 2004 9 96.209 0.247 4 2004 10 95.997 0.534 4 2004 11 95.553 0.455 3 2004 12 95.910 0.251 4 2005 1 96.000 0.133 1 2005 2 95.733 0.375 5 2005 3 95.893 0.207 2 2005 4 95.481 0.178 4 2005 5 95.639 0.186 5 2005 6 95.248 0.303 3 2005 7 95.114 0.169 4 2005 8 95.026 0.310 5 2005 9 94.756 0.320 4 2005 10 94.716 0.220 4 2005 11 94.600 0.185 4 2005 12 94.170 0.492 2 2006 1 94.716 0.178 2 2006 2 94.174 0.288 3 2006 3 94.421 0.325 3 2006 4 94.310 0.226 3 2006 5 94.188 0.172 4 2006 6 93.799 0.234 4 2006 7 93.701 0.414 4 2006 8 93.794 0.272 5 2006 9 93.529 0.955 2 2006 10 93.391 0.233 4 2006 11 93.534 0.262 5 2006 12 93.408 0.198 2 2007 1 93.671 0.469 3 2007 2 93.001 0.288 3 2007 3 92.994 0.252 4 2007 4 93.239 0.178 2 2007 5 92.982 0.296 2 2007 6 93.203 0.209 4 2007 7 93.062 0.315 4 2007 8 92.970 0.262 4 2007 9 92.961 0.426 4 2007 10 92.106 0.397 4 2007 11 92.227 0.183 3 2007 12 92.012 0.304 2 2008 1 92.049 0.188 3 2008 2 91.977 0.165 3 2008 3 91.931 0.176 4 2008 4 91.561 0.231 5 2008 5 91.871 0.211 3 2008 6 91.660 0.290 4 2008 7 90.869 0.212 4 2008 8 90.736 0.257 4 2008 9 90.438 0.266 2 2008 10 90.911 0.261 5 2008 11 90.625 0.225 4 2008 12 90.227 0.433 5 2009 1 90.480 0.589 1 2009 2 90.066 0.339 3 2009 3 90.028 0.187 4 2009 4 89.714 0.193 4 2009 5 89.712 0.247 2 2009 6 89.944 0.216 3 2009 7 89.656 0.253 3 2009 8 90.024 0.430 4 2009 9 89.981 0.220 4 2009 10 89.861 0.211 4 2009 11 90.213 0.523 3 2009 12 89.752 0.186 3 2010 1 90.181 0.590 3 2010 2 89.890 0.175 4 2010 3 89.841 0.300 3 2010 4 89.836 0.515 4 2010 5 89.337 0.191 4 2010 6 89.346 0.398 4 2010 7 88.939 0.174 3 2010 8 89.111 0.253 2 2010 9 88.886 0.332 3 2010 10 88.717 0.184 4 2010 11 88.843 0.278 3 2010 12 88.969 0.390 3 2011 1 88.569 0.296 4 2011 2 89.022 0.707 2 2011 3 88.444 0.214 4 2011 4 88.494 0.286 3 2011 5 87.773 0.204 4 2011 6 87.712 0.290 2 2011 7 87.753 0.325 2 2011 8 87.636 0.268 3 2011 9 88.051 0.236 2 2011 10 87.586 0.281 3 2011 11 87.615 0.228 3 2011 12 87.380 0.431 1 2012 1 87.453 0.160 2 2012 2 87.045 0.157 3 2012 3 87.088 0.290 4 2012 4 86.572 0.339 2 2012 5 86.600 0.252 3 2012 6 86.833 0.511 4 2012 7 86.918 0.456 3 2012 8 86.809 0.325 2 2012 9 85.852 0.213 3 2012 10 87.015 1.089 2 2012 11 86.330 0.385 1 2012 12 86.263 0.290 2 2013 1 86.311 0.467 2 2013 2 86.289 0.591 3 2013 3 86.397 0.580 2 2013 4 85.601 0.234 3 2013 5 86.105 0.237 4 2013 6 86.250 1.151 1 2013 7 85.451 0.466 3 2013 8 85.270 3.498 1 2013 9 85.160 2.514 1 2013 10 nan nan 0 2013 11 nan nan 0 2013 12 84.982 0.192 2 2014 1 84.715 0.358 3 2014 2 84.772 0.290 2 2014 3 nan nan 0 2014 4 nan nan 0 2014 5 nan nan 0 2014 6 nan nan 0 2014 7 84.310 0.184 2 2014 8 84.726 0.161 4 2014 9 85.227 0.480 4 2014 10 84.334 0.281 4 2014 11 84.358 0.286 3 2014 12 84.411 0.191 2 2015 1 nan nan 0 2015 2 83.960 0.754 1 2015 3 83.793 0.275 2 2015 4 nan nan 0 2015 5 83.530 0.399 1 2015 6 83.582 0.506 5 2015 7 83.590 0.339 2 2015 8 83.166 0.213 4 2015 9 83.307 0.221 5 2015 10 83.061 0.183 2 2015 11 82.776 0.453 2 2015 12 83.082 0.322 3 2016 1 82.270 0.561 1 2016 2 83.105 0.414 3 2016 3 81.926 0.359 2 2016 4 81.850 0.888 1 2016 5 82.398 0.424 4 2016 6 82.370 0.378 1 2016 7 82.240 0.911 1 2016 8 82.136 0.388 3 2016 9 82.033 0.959 3 2016 10 81.830 0.289 1 2016 11 82.049 0.322 3 2016 12 82.645 0.615 2 2017 1 82.135 0.297 2 2017 2 82.167 0.410 2 2017 3 81.891 0.389 2 2017 4 81.870 0.670 3 2017 5 81.501 0.318 4 2017 6 81.597 1.315 2 2017 7 81.494 0.334 3 2017 8 81.263 0.215 3 2017 9 81.373 0.905 2 2017 10 81.070 0.641 3 2017 11 81.296 0.631 3 2017 12 80.988 0.495 3 2018 1 81.310 0.357 1 2018 2 79.896 0.390 3 2018 3 nan nan 0 2018 4 80.335 0.630 4 2018 5 81.083 0.215 2 2018 6 79.939 0.672 2 2018 7 nan nan 0 2018 8 nan nan 0 2018 9 79.093 0.566 2 2018 10 79.965 0.297 2 2018 11 79.870 0.395 2 2018 12 79.652 0.984 2 2019 1 nan nan 0 2019 2 79.078 0.350 3 2019 3 79.484 0.410 2 2019 4 79.450 0.240 3 2019 5 79.669 0.235 2 2019 6 79.909 0.417 2 2019 7 79.904 0.271 4 2019 8 78.610 0.213 1 2019 9 nan nan 0 2019 10 nan nan 0 2019 11 nan nan 0 2019 12 nan nan 0