Creating MAGICC Scenario Files
How to create your own emission scenario file for MAGICC6?
This is a quick recipe of how you can put your data into a ASCII fileformat that will work with MAGICC. Example files of the RCP scenarios can be downloaded from the RCP concentration calculations site [only links labled "MAGICC"], e.g. RCP3-PD (sometimes as well called RCP2.6), RCP45, RCP6, or RCP85. Suitable scenario files have always the extension *.SCEN.
What ingredients do you need?
1. In order to create an emission scenario file, you need the emission scenario data. Specifically, you need:
- Fossil / Industrial carbon dioxide CO2 emissions in units GtC/yr (to convert from GtCO2/yr to GtC/yr, multiply by '12/44')
- Landuse carbon dioxide CO2 emissions in units GtC/yr
- Methane CH4 emissions in units MtCH4/yr
- Nitrous oxide N2O emissions in units MtN/yr (note that to convert from MtN2O/yr to MtN/yr, multiply by '28/(28+16)')
- Sulphate dioxide SO2 emissions in units MtS/yr
- Carbon monoxide CO emissions in units MtCO/yr
- Non-Methane Volatile Organic compounds NMVOC in units Mt/yr
- Nitrogen Oxides NOx in units MtN/yr
- Black Carbon BC in units Mt/yr
- Organic Carbon OC in units Mt/yr
- Ammonium NH3 in MtN/yr
- Perfluorocarbons PFCs in the units kt/yr, namely CF4, C2F6, C6F14
- Hydrofluorocarbons HFCs in the units kt/yr, namely HFC23, HFC32, HFC43-10, HFC125, HFC134a, HFC143a, HFC227ea, HFC245fa
- Sulfur hexafluoride SF6 in units kt/yr
2. You need all these emission trajectories on the same points in time. MAGICC assumes linear interpolation between any years that are not provided. Thus, your time axis could either be 2000, 2005, 2050 and 2100, or, annual values or any other sequence of years as long as they monotonically increase. Note that historical emissions files are overwritten from the startpoint onwards, i.e. with the startpoint being your first year of your emission scenario, i.e. 2000 or 1990 or 2005.
3. Optionally, you can prescribe all this data regionally. This has the advantage that MAGICC does not have to make guesses on what the regional distribution of your emissions are over time. The regional split up follows the five RCP regions, i.e. OECD, REF, ASIA, MAF and LAM, (where MAF and LAM are together the former ALM region of the SRES scenarios), as defined here. In addition, you should specify emissions from international transport (i.e. the sum of aviation and shipping emissions) separately as the sixth region. Note that if you provide regional data, MAGICC expects the order of these data blocks to be GLOBAL, OECD, REF, ASIA, MAF, LAM, BUNKERS. And yes, globally aggregate emissions should be provided as well (although they will be ignored, if MAGICC is told to use the regional data..).
How do I format my scenario data?
Now that you have all your data, you have to take into account some formatting requirements of your ASCII .SCEN file.
- Your file ending should be ".SCEN" and it should be an ASCII file under DOS standard.
- The first line in your ASCII file consists of only one integer, ("20" in the example below), which specifies the number of prescribed years of your emission trajectory. For example, if your emission scenario is specified for the years, 2000, 2005, 2050 and 2100, then "4" is the number you should put into the top left corner of your ASCII file.
- The second line consists of only one integer. Simplified speaking, this integer stands for whether you provide global data or regional data. The options are:
- 11 - Global/World data only.
- 21 - Global/World data plus the four SRES regions OECD90, REF, ASIA and ALM. See regional definition here.
- 31 - Global/World data plus the five RCP regions OECD, REF, ASIA, MAF and LAM.
- 41 - Global/World data plus the five RCP regions OECD, REF, ASIA, MAF and LAM and international transport "BUNKERS".
- The third line specifies the scenario name. Usually identical to the filename.
- The fourth and fifth line are there for describing your scenario.
- The sixth line is empty.
- The seventh line contains WORLD as the regional definition for the first datablock.
- The eights line contains first the YEARS column header and then the headers with the list of gases (note, column order is not variable, but fixed as shown in the example below).
- The ninth line contains the units (only for the viewer as MAGICC expects the data to be in units as specified above).
- The tenth line is the first data line. Note that the field width has to be 11 for every data column - with the years being integers and the other emissions being floating point numbers with four digits after the dot, as MAGICC uses the Fortran command READ(FILE_ID , '(I11 , 24F11.4)') to read in these datablock lines.
- There are X data lines in total (including line 10), with X being the integer read in in the first line.
- Afterwards, there are TWO empty lines as separator
- Then, if regional flag is not set to 11, the header for the next regional block comes, i.e. "OECD".
- Then there is one line with column headers (i.e. years and gas names)
- Then there is one line with Units
- Then comes the next data block and so on..
- After the last data block, two empty lines are again provided as separator.
- Below these two empty lines, additional comments can be inserted, which will be ignored by MAGICC.
Please note: If you create unexpected curves with your scenario
Please make sure that your data start in line 10 and end in line 10 + the value from line 1. For example, adding an extra empty line between YEARS and UNITS or discard a comment line (line 3 or 4) will corrupt the SCEN file.
This is how the header and first dataline of an emission scenario .SCEN file should look like. In this example, an array of 20 annual datapoints has been provided (hence first integer in line 1 being "20"), and the data is provided with regional detail of the RCP regions (plus bunkers) (hence "41" in second line, see description above). For full examples, see these files RCP3-PD (sometimes as well called RCP2.6), RCP45, RCP6, or RCP85.
20 41 RCP3PD HARMONISED, EXTENDED FINAL RCP3-PD (Peak&Decline) Emission scenario for MAGICC6 DATE: 26/11/2009 11:29:06; MAGICC-VERSION: 6.3.09, 25 November 2009 WORLD YEARS FossilCO2 OtherCO2 CH4 N2O SOx CO NMVOC NOx BC OC NH3 CF4 C2F6 C6F14 HFC23 HFC32 HFC43-10 HFC125 HFC134a HFC143a HFC227ea HFC245fa SF6 Yrs GtC GtC MtCH4 MtN2O-N MtS MtCO Mt MtN Mt Mt MtN kt kt kt kt kt kt kt kt kt kt kt kt 2000 6.7350 1.1488 300.2070 7.4567 53.8413 1068.0009 210.6230 38.1623 7.8048 35.5434 40.0185 12.0000 2.3750 0.4624 10.3949 4.0000 0.0000 8.5381 75.0394 6.2341 1.9510 17.9257 5.5382 2001 6.8960 1.1320 303.4093 7.5029 54.4192 1066.7447 211.5938 38.2888 7.8946 35.7143 40.3916 11.9250 2.4344 0.4651 10.4328 5.3987 0.6470 9.0301 84.0409 7.4947 1.6450 19.7183 5.6990 2002 6.9490 1.2317 306.5787 7.5487 54.9960 1065.4692 212.5632 38.4153 7.9841 35.8846 40.7647 11.8480 2.4915 0.4058 10.4708 6.7974 1.2941 9.8853 94.7162 8.7389 2.5080 21.5109 5.8596 2003 7.2860 1.2256 309.7165 7.5942 55.5716 1064.1742 213.5311 38.5418 8.0734 36.0543 41.1377 11.7692 2.5464 0.3939 10.5083 8.1961 1.9411 12.0788 101.4157 9.9776 3.3410 23.3034 6.0202 2004 7.6720 1.2428 312.8241 7.6394 56.1461 1062.8596 214.4977 38.6683 8.1624 36.2233 41.5107 11.6885 2.5990 0.4062 10.5455 9.5948 2.5881 12.5074 113.9297 11.2136 4.2690 25.0960 6.1806 ...
Then, simply upload your scenario file on live.magicc.org and calculate climate effects following your own emission scenario.