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pmip3:wg:degla:bc:ghg [2015/03/02 10:22]
ruza
pmip3:wg:degla:bc:ghg [2015/10/21 13:42] (current)
ruza
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 The data will be provided on the AICC2012 timescale of [[http://​www.clim-past.net/​9/​1733/​2013/​cp-9-1733-2013.html | Veres et al. (2013)]]<​sup>​[2]</​sup>​. \\ The data will be provided on the AICC2012 timescale of [[http://​www.clim-past.net/​9/​1733/​2013/​cp-9-1733-2013.html | Veres et al. (2013)]]<​sup>​[2]</​sup>​. \\
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-**EPICA Dome C and the PMIP3 LGM** ((Plot produced by Lauren Gregoire, ​Feb 2015)) \\ +**EPICA Dome C and the PMIP3 LGM** ((Plot produced by Lauren Gregoire, ​April 2015)) \\ 
-{{ http://​homepages.see.leeds.ac.uk/​~earri/​pmip_deglac/​CH4.png| EPICA Dome C CH4 }} \\+{{ :pmip3:​wg:​degla:​bc:​ch4.png | EPICA Dome C CH4 }} \\
 Also note how the new AICC2012<​sup>​[2]</​sup>​ age model affects the '​LGM'​ (21 ka; vertical dashed line) CH<​sub>​4</​sub>​ value.\\ Also note how the new AICC2012<​sup>​[2]</​sup>​ age model affects the '​LGM'​ (21 ka; vertical dashed line) CH<​sub>​4</​sub>​ value.\\
  
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 ===== Nitrous Oxide ===== ===== Nitrous Oxide =====
  
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 Please think about the following points and add any comments on these or any other aspects of the experiment design to the discussion section below: [Topics will be added here as they are raised below or by email.] Please think about the following points and add any comments on these or any other aspects of the experiment design to the discussion section below: [Topics will be added here as they are raised below or by email.]
-  * With the new AICC2012<​sup>​[2]</​sup>​ age model, the LGM values for CO<​sub>​2</​sub><​sup>​[1]</​sup>​ and CH<​sub>​4</​sub><​sup>​[4]</​sup>​ are inaccurate, as can be seen from the plots above. Do we need a new PMIP LGM definition for these greenhouse gases in accordance with the records? \\ \\ +  ​* **RESOLVED** With the new AICC2012<​sup>​[2]</​sup>​ age model, the LGM values for CO<​sub>​2</​sub><​sup>​[1]</​sup>​ and CH<​sub>​4</​sub><​sup>​[4]</​sup>​ are inaccurate, as can be seen from the plots above. Do we need a new PMIP LGM definition for these greenhouse gases in accordance with the records? ​**DECISION (Oct 2015): We have used the new, up to date CO<​sub>​2</​sub>​ (188 ppm) and CH<​sub>​4</​sub>​ (375 ppb) values for our LGM equilibrium-type 21 ka spinup. We do not know what the LGM group'​s decision will be.**\\ \\ 
-  * N<​sub>​2</​sub>​O<​sup>​[1]</​sup>​ values take a dive in the lead up to 21 ka. The PMIP3 value of 200 ppb looks fairly representative of the LGM state, even though this is a bit higher than the actual 21 ka value. We recommend that groups spin-up with 200 ppb N<​sub>​2</​sub>​O,​ and begin the transient simulation from 21 ka in the record (as shown in the plot above). ​ \\ \\ +  ​* **RESOLVED** N<​sub>​2</​sub>​O<​sup>​[1]</​sup>​ values take a dive in the lead up to 21 ka. The PMIP3 value of 200 ppb looks fairly representative of the LGM state, even though this is a bit higher than the actual 21 ka value. We recommend that groups spin-up with 200 ppb N<​sub>​2</​sub>​O,​ and begin the transient simulation from 21 ka in the record (as shown in the plot above). ​**DECISION (Oct 2015): We have stuck with the old, more representative N<​sub>​2</​sub>​O value of 200 ppb. However, the transient '​spinup'​ 26-21 ka and the transient run (21-9 ka) should use the chronologically accurate values, as plotted above. We do not know what the LGM group'​s decision will be.** \\ \\ 
-  * Should the core experiment use the [[http://​www.nature.com/​nature/​journal/​v514/​n7524/​full/​nature13799.html | Marcott et al. (2014)]]<​sup>​[3]</​sup>​ CO<​sub>​2</​sub>​ records? \\ For example, these newer data are higher resolution than [[http://​www.nature.com/​nature/​journal/​v453/​n7193/​full/​nature06949.html | Lüthi et al. (2008)]]<​sup>​[1]</​sup>,​ but are restricted to 23-9 ka. Therefore more consistency may be be gained from using the older [[http://​www.nature.com/​nature/​journal/​v453/​n7193/​full/​nature06949.html | Lüthi et al. (2008)]]<​sup>​[1]</​sup>​ CO<​sub>​2</​sub>​ records, if longer simulations are planned by groups. Also, CH<​sub>​4</​sub>​ and N<​sub>​2</​sub>​O data are not yet available in such high resolution. \\ \\+  ​* **RESOLVED** Should the core experiment use the [[http://​www.nature.com/​nature/​journal/​v514/​n7524/​full/​nature13799.html | Marcott et al. (2014)]]<​sup>​[3]</​sup>​ CO<​sub>​2</​sub>​ records? \\ For example, these newer data are higher resolution than [[http://​www.nature.com/​nature/​journal/​v453/​n7193/​full/​nature06949.html | Lüthi et al. (2008)]]<​sup>​[1]</​sup>,​ but are restricted to 23-9 ka. Therefore more consistency may be be gained from using the older [[http://​www.nature.com/​nature/​journal/​v453/​n7193/​full/​nature06949.html | Lüthi et al. (2008)]]<​sup>​[1]</​sup>​ CO<​sub>​2</​sub>​ records, if longer simulations are planned by groups. Also, CH<​sub>​4</​sub>​ and N<​sub>​2</​sub>​O data are not yet available in such high resolution. ​**DECISION (Oct 2015): We have chosen to use the older data from [[http://​www.nature.com/​nature/​journal/​v453/​n7193/​full/​nature06949.html | Lüthi et al. (2008)]]<​sup>​[1]</​sup>​.** ​\\ \\
  
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pmip3/wg/degla/bc/ghg.1425291720.txt.gz · Last modified: 2015/03/02 10:22 by ruza