This is part of the labels / documentation for <a href='http://jcm.chooseclimate.org'>Java Climate Model</a><hr/>

#oghga		¨oldJCM4		§£>jcm.mod.ogas

#othgasplot		¨oldJCM4		§£>jcm.mod.ogas

#othgasemit		¨oldJCM4 addJCM5		§This module calculates scenarios for the global emissions of non-CO2 gases.

These are based on @aboutsres, scaled-down in some cases, depending on the @objective and the parameter  @othgasemitoptions.

Note also:<ul>
<li>@socreg (in @jcm.mod.soc package) also includes regional emissions of CH4 and N2O. Their totals should be consistent with the global figures shown here. 
<li> @aviashipemit are considered separately
<li>The effect of these emissions on concentrations and radiative forcing are calculated in @atchem, @fgas and @aerosol modules.
<li> Some ideas for @othgasemitfuture
</ul>

#sresfix		¨oldJCM4		§This option simply sets the other gas emissions according to the no-policy SRES scenario chosen from @sresmenu, with no mitigation. This is the option used in IPCCTAR-Synthesis report, with scenario @A1B (see @ipccothgas).

#sresscale		¨oldJCM4		§This is the default option to scale-down emissions in <b>all</b> @stabilisation scenarios in JCM.

The emissions of all gases are reduced in the same proportion, compared to a baseline SRES scenario  (choose from @sresmenu). The formula is:

(Em<sub>g,y</sub> / Es<sub>g,y</sub>) = (Em<sub>c,y</sub> / Es<sub>c,y</sub>)

Where: Em=mitigated emissions, Es=SRES emissions

c = CO2, g = any other gas, y = year

#2000fix		¨oldJCM4		§Other gas emissions are fixed  at their 2000 level, useful for comparing the effect of their different lifetimes (see @atchem)

#2000scale		¨oldJCM4		§This option reduces the emissions of all gases in the same proportion, compared to their 2000 level. The formula is:

(Em<sub>g,y</sub> / E<sub>g,2000</sub>) = (Em<sub>c,y</sub> / E<sub>c,2000</sub>)

Where: Em=mitigated emissions, c = CO2, g = any other gas, y = year

#ohef		¨oldJCM4		§This option enables you to switch off the variable lifetimes due to changing OH. 
See @aboutoho3 for more explanation 

%%(note, when this option is disabled, the historical concentrations are not consistent with measurements!)%%

#o3s1930		¨oldJCM4		§An expert parameter, providing the option to calculate the forcing for stratospheric ozone from a baseline of 1930 (when fgas data begins) rather than 1970 (as in IPCC-TAR )

#taro3		¨oldJCM4		§The original formula for calculating tropospheric ozone in IPCC TAR 
(see @atchemformulae) was corrected (by the same authors) to be more consistent with historical concentrations. 
¤cogs Select this option for reproducing IPCC datatables made using the old formulae. - see @compareipcc

#oghgahowwork		¨oldJCM4		§£>atchemformulae

#atchem		¨oldJCM4 addJCM5		§This module concerns the atmospheric chemistry and radiative forcing of CH4, N2O and O3 precursors (note that @fgas are in a separate module). 

Greenhouse gases other than CO2 are removed from the atmosphere mainly by chemical oxidation. %%(whereas CO2 is instead absorbed into the ocean and biosphere sinks  - see @berncarbon).%%

The atmospheric lifetimes of each gas vary widely. Tropospheric Ozone survives only a few days in the atmosphere, the lifetime of CH4 is just under a decade (depending on OH, see below), whilst the lifetime of N2O is just over a century (similar to CO2).

  The model includes the overlap in the radiative forcing of CH4 and N2O, and the small cooling effect of water vapour produced by the oxidation of methane in the stratosphere.

££aboutoho3

---- ===Experiments===
%% ¤adju Choosing the option "2000 fixed" from the @othgasemitoptions shows the effect of different lifetimes (CH4 and ozone concentrations level off rapidly, N2O much more slowly). %%

%% ¤cogs regarding comparison of JCM projections with those from IPCC-TAR-WG1-SRESappx, see @compareipcc, noting the @tarO3 option. %%

#oghgafuture		¨fut		§£>othgasemitfuture

#cfc		¨oldJCM4		§see @fgasplot for details

#hfc		¨oldJCM4		§see @fgasplot for details

#jcm.mod.ogas		¨addJCM5		§This package contains  modules relating to the emissions, atmospheric chemistry, concentration and radiative forcing of all gases except CO2, i.e. CH4, N2O, Ozone (from NOx, CO and VOCs), F-gases (CFCs, HFCs, PFCs, SF6), and sulphate and carbon aerosols. Effects of solar variability and volcanos are also included with the aerosols.

Unlike CO2, the oher greenhouse gases are removed from the atmosphere mainly by oxidation. Their lifetimes vary widely and are affected by feedbacks involving OH radicals - see @atchem. @aerosol effects act on an even shorter timescale, but still make an important contribution to @radfor.

%%Note: Modules in this package are concerned only with **global** emissions and their contributions to **global** forcing and temperature. However the @jcm.mod.soc package also includes some of these gases.%%

<hr>
¤adju You can see how the relative contributions of each gas change, comparing @plots of <ul><li>@othgasemitcurves <li>@atchem&conc <li>@atchem&rf </ul>
¤pan Note also more detailed £`qtsets in @aerosol, @fgas and @aviationforcing. modules. To see everything together in one plot, look at  @allrf_detail .

#aviationforcing		§This module calculates the radiative forcing (see @radforintro) due to aviation emissions, including:{{
*:CO2
*:Ozone (derived from NOx etc.) 
*:CH4 (derived from NOx etc.)
*:water vapour (direct effect -warming)
*:sulphate aerosols (cooling) 
*:carbon aerosols (warming).
}}

It is important to consider all these gases and aerosols, since the total forcing from aviation is about 2-4 times greater than that from CO2 alone, depending on various uncertainties, and the way of integrating over time. This ratio can be explored by considering the @radiative_forcing_index

Aviation emissions (both domestic and international) are calculated in @AviaShipEmit module, based on scenarios in the  IPCC special report on aviation, (optionally scaled down for stabilisation scenarios).

Projections of forcing in this report for the scenario Fa1 were also used as a basis for scaling other scenarios, taking into account the changing ratio of NOx / CO2 emissions.  
O3 and CH4 forcing were scaled by NOx, whereas the other effects (including aerosols and cirrus) were scaled by CO2.

The @update_tradeoff03 option (enabled by default) applies a correction factor to update these forcings. They may be further modified by applying the @include_efficacy_factor parameter  based on recent studies of Hansen, Ponater et al. (this applies to all gases, so it is in the @radfor module). 

%%¤cogs An option @exclude_aviation_non-co2 is provided in @radfor module, to enable comparison with older scenarios in which aviation contrails and ozone were not included, such as the  tabulated scenario data in IPCC-TAR. This does **not** affect this £`aviationforcing module %%
----
¤jcmb This module was developed for application in the project Aviation and the Belgian Climate, Impacts and Integration Options (see @acknowsupport)