Forest sink and SHAPE curve

[Neha Jaggeshar]

Hi all,

A quick follow-up from a previous discussion on representing forest saturation with increasing stand age using the SHAPE attribute.

In my model, I’ve defined the forest stock process with the attributes NCAP_PASTI~2006, LIFE, and a removals factor defined with env~act. I’ve also defined the shape curve using FLO_FUNCX.

My expectation was that the removal results would decrease as stand age increases, but I’m getting nearly identical values whether I run the model with or without the SHAPE factor. I suspect I’m misunderstanding something or missing a step, though I can’t pinpoint what it is.

I’ve included the details in the attached file. Any clarification would be helpful. 




Thanks, 

Neha

[Antti-L]

Looks like you are not defining FLO_FUNCX as it should be (the CG index seems missing from the specification).
Could you please show the FLO_FUNCX parameters from Items Detail → Data, or from Browse, such that all dimensions of it are shown. Or, alternatively, please attach the DD file for the scenario, where you define the FLO_FUNCX parameters with the TFM_INS table.

In addition, bear in mind that the process must be vintaged in order to make SHAPE working for FLO_EMIS. I could not see the FI_Process table in your attachment to verify that.

[Neha Jaggeshar]

Hi, 

Here's the DD file. 
And yes, I did set that process to vintage.

[Antti-L]

Yes, the commodity group was missing from the specification (see extract from the DD file below).
If you read the documentation, you can see that when shaping FLO_EMIS, you should specify the emission commodity as the CG:  FLO_FUNCX(reg,year,prc,com,com) = N;

FLO_FUNCX ' '/
'IE'.0.'FORStock'.'commodity_group'.'FORSINKCO2' 1
'IE'.2018.'FORStock'.'commodity_group'.'FORSINKCO2' 2
'IE'.2070.'FORStock'.'commodity_group'.'FORSINKCO2' 2
/;

[Neha Jaggeshar]

Hi Antti,

I’ve created a new set in TFM_Csets and then added this set into TFM_COMGRP in SysSettings by entering the set name in both the CSet_Set and Name fields. However, the commodity group still does not appear in my scenario DD file. 
I can see the predefined group FORStock_ENVO, but I have not modified it. In the Item List, the commodity FORSINKCO2 is visible and correctly shows its emission as a member. 

What I am unsure about is whether I need to modify the predefined FORStock_ENVO group, or whether something needs to be added in the BASE scenario file.  I’m also wondering whether the SHAPE profile table requires an additional column header for the CommGrp? 

Could you let me know what I might be missing?

[Antti-L]

I am not sure that I am able to follow, sorry.
If you are talking about the earlier issue (where I said that the CG was not specified), then the solution to that is very simple: just add FORSINKCO2 as the missing CG into FLO_FUNCX.  Under VEDA, it goes to the Other_indexes column in a TFM_INS table, and so just add FORSINKCO2 into the Other_indexes column in the three rows where you defined FLO_FUNCX, and that's it. Commodities are indeed also commodity groups, if that's what caused you confusion.

But if you are now talking about some other issue, it is not clear to me what it is...

[Neha Jaggeshar]

I am not sure that I am able to follow, sorry.
If you are talking about the earlier issue (where I said that the CG was not specified), then the solution to that is very simple: just add FORSINKCO2 as the missing CG into FLO_FUNCX.  Under VEDA, it goes to the Other_indexes column in a TFM_INS table, and so just add FORSINKCO2 into the Other_indexes column in the three rows where you defined FLO_FUNCX, and that's it. Commodities are indeed also commodity groups, if that's what caused you confusion.

But if you are now talking about some other issue, it is not clear to me what it is...

Thanks, Antti!
Sorry for the absolute confusion 
I over-complicated the issue myself. I misunderstood your original comment about the missing commodity group, and I thought I needed to set up a full TFM_COMGRP definition.

[Neha Jaggeshar]

Hi Antti, 

I am struggling to shape the emissions based on age - mostly because I'm failing in understanding how the years are taken into account when defining the FLO_FUNCX and the shape indexes options to use. 
I did refer to the previous threads Defining dynamic emission factors / How to set emission factor by age?, but it is still a little unclear to me. 

FORStock is the vintage process that i want to have the dynamic emissions (FORSINKCO2). The year of installation for FORStock is 2006; my baseline year is 2018 extending to 2070



The shape curve is defined as: 


I expected the model to recognize that the forests are vintage 2006 (age 12 in 2018) and apply SHAPE(12) ≈ 0.92, if i am getting this part right? 
But instead it is applying SHAPE(1) = 0.25, which shows in the smaller sequestration than expected compared to non-vintage runs: 





I am most probably not defining the years correctly in the SHAPE profile. Any help on where I'm going wrong is much appreciated. 

Thanks, 
Neha

[Antti-L]

The emissions are defined per activity, but I am not able to see the activity in your results.  Could you thus please show the VAR_ACT results for the ForStock process as well, in order to see the relation between the activity and the FORSINKCO2 flow?

Moreover, you should show the flows and activities by vintage as well, because now I see that you are defining several NCAP_PASTI for years 2006, 2012, 2017, 2022, and the you have the FORSINKCO2 shape for all of them.

[Neha Jaggeshar]

The VAR_ACT results: 

[Antti-L]

Ok thanks, but I just noticed that you are defining several NCAP_PASTI for years 2006, 2012, 2017, 2022, and you have the FORSINKCO2 shape for all of them.  Therefore, you should show the flows and activities by vintage as well, because now from the results, one cannot see the mapping of the flow by vintage, to see how the shape is in fact working.

[Neha Jaggeshar]

Ok thanks, but I just noticed that you are defining several NCAP_PASTI for years 2006, 2012, 2017, 2022, and you have the FORSINKCO2 shape for all of them.  Therefore, you should show the flows and activities by vintage as well, because now from the results, one cannot see the mapping of the flow by vintage, to see how the shape is in fact working.

Sorry, I missed this part in the previous reply. 
The NCAP_PASTI defined for the other years is in a separate scenario file, which i did not run for test4 v/s no vintage. If this clarifies anything.

[Antti-L]

Ok, that does make me confused. But can you still show the vintage for those VAR_ACT / VAR_FOUT results? Just drag the Vintage dimension down to the rows section.

[Neha Jaggeshar]

[Antti-L]

There you go! The 2006 vintage is missing completely in the results.
There are apparently new investments into the process, and all activity is occurring for those new vintages only. I think that would explain the issue well. I guess you should prohibit new investments to this process. Try setting NCAP_BND(r,'0','ForStock','UP')=2.