‘The same thing as doing nothing’: MAGICC Simulator of state-by-state theoretical ‘warming’ averted by 100% reduction in CO2

By: - Climate DepotNovember 25, 2019 11:29 AM


MAGICC: Model for the Assessment of Greenhouse-gas Induced Climate Change

By Gregory Wrightstone

See detailed description, disclaimer and credits below

Additional simulation results using different climate sensitivities and also  results for the entire industrialized nations (including US) can be  accessed using the super-cool Inconvenient App for smartphones found at  the Google Play Store for Android and at the App Store for iPhone.

The results are produced from climate change calculations performed using the MAGICC climate model simulator (MAGICC: Model for the Assessment of Greenhouse-gas Induced Climate Change).  MAGICC was developed by scientists at the National Center for  Atmospheric Research under funding by the U.S. Environmental Protection  Agency.

The detailed description and complete methodology for the calculations can be found here at the magicc.com website. More information from the horse’s mouth are listed below:

Model Description – See what is behind MAGICC, a complete scientific description of datasets and parameterisations used in MAGICC6. (MAGICC changelog)

Access MAGICC6 online – Help files and instructions for using our online interface live.magicc.org for running MAGICC6 on our servers.

Download MAGICC6 – Download and installation instructions for MAGICC6 executable.

Frequently Asked Questions – Find answers to the frequently asked questions regarding the Magicc6 model.

For IAM Modellers – Find information if you like to include MAGICC in an Integrated Assessment Model.

MAGICC Projects – See a list of publications that have made various uses of MAGICC in the past.

MAGICC Team – Meet the MAGICC Development Team, Tom Wigley, Sarah Raper and Malte Meinshausen.

A “simpler” explanation can be found at the CATO Institute’s webpage here and excerpted below:

The  results from our calculator are produced from climate change  calculations performed using the MAGICC climate model simulator (MAGICC:  Model for the Assessment of Greenhouse-gas Induced Climate Change).  MAGICC was developed by scientists at the National Center for  Atmospheric Research under funding by the U.S. Environmental Protection  Agency.

We  are not creative enough to have made that acronym up. MAGICC is itself a  collection of simple gas-cycle, climate, and ice-melt models to  efficiently emulate the output of complex climate models. MAGICC  produces projections of the global average temperature and sea level  change under user configurable emissions scenarios and model parameters.  MAGICC is run using its default model parameter settings except for  climate sensitivity, which you can choose from between 1.5°C and 4.5°C.

The  baseline emissions scenario against which all climate dioxide  reductions were measured is scenario A1B from the IPCC’s Special Report  on Emissions Scenarios (SRES). Scenario A1B is a middle-of-the-road  emissions pathway which assumes rapid carbon dioxide emissions growth  during the first half of the 21st century and a slow CO2 emissions  decline thereafter. Emissions are prescribed by country groups. Our  “Industrialized Countries” group is the OECD90 countries (which includes  North America, Western Europe, and Australia, New Zealand and Japan.)

In  order to obtain the baseline emissions from the United States to which  the emissions reduction schedule could be applied, the U.S. emissions  were backed out from the OECD90 country grouping. To do so, the current  percentage of the total group emissions that are being contributed by  the United States was determined—which turned out to be right around  50%. We assume that this percentage will be constant over time. In other  words, that the U.S. contributed 50% of the OECD90 emissions in 2000 as  well as in every year between 2000 and 2100. In this way, the future  emissions pathway of the U.S. was developed from the group pathway  defined by the IPCC for the A1B scenario.

From  these baselines (either the U.S. baseline or the OECD90 baseline),  carbon dioxide emissions reductions were applied linearly from 2005 to  2050 to obtain the user-specified total reduction. The new (reduced)  emissions were recombined with the other (unadjusted) IPCC country  groupings to produce the global emissions total. It is the total global  emissions that are entered into MAGICC to yield global temperature  projections. The results using the reduced emissions pathway were then  compared to the results using the original A1B pathways as prescribed by  the IPCC, with the baseline against which temperature changes were  calculated set to the year 2010.

We  assume that a carbon tax would only be applied to reduce carbon dioxide  emissions. In practice however, the only way to reduce carbon dioxide  emissions is to reduce the burning of fossil fuels. Reducing the burning  of fossil fuels will have co-impacts such as reducing the emissions of  carbon monoxide (CO), volatile organic compounds (VOCs), nitrogen oxides  (NOx), and sulfur oxides (SOx). The first three chemical compounds  generally enhance warming while the latter generally retards it.  Sensitivity tests using MAGICC indicate that for the OECD90 countries  under the A1B pathway, the effect of collective changes in these  co-emissions is largely compensative.

Additional  fine print on precision: The temperature savings are presented to three  significant digits in order to tell the results apart. In the real  world, the impacts from the emissions reduction pathways are not nearly so precise and, in fact, the temperature savings from most of the  different carbon dioxide emissions reduction pathways are scientifically  impossible to tell apart from each other, and in many cases, are  impossible to tell apart from the original A1B scenario, i.e., they are the same thing as doing nothing.


Related Links: 

Flashback 2015: Then Sec. of State John Kerry explains climate futility: If U.S. zeroed out CO2 emissions, it ‘still wouldn’t be enough to offset the carbon pollution coming from the rest of the world’ – John Kerry in 2015: “The fact is that even if every American citizen biked to work, carpooled to school, used only solar panels to power their homes, if we each planted a dozen trees, if we somehow eliminated all of our domestic greenhouse gas emissions, guess what – that still wouldn’t be enough to offset the carbon pollution coming from the rest of the world.

‘The number is so small as to be undetectable’ – Pure Symbolism – EPA Climate Regs Avert 0.018°C Temperature Rise – That’s ‘less than two one-hundredths of a degree C’ – The Vital Number Missing from the EPA’s ‘By the Numbers’ Fact Sheet

Even EPA Climate Models Show The ‘Green New Deal’ Would Have No Detectable Impact On Global Temps –  Even if all the Green New Deal’s goals were achieved, it would have a negligible, and likely immeasurable, impact on projected global warming, according to climate model simulation provided by a libertarian think tank.