Why post atmospheric CO2 readings on their own?  Why not CO2-equivalent?  What about atmospheric methane?  Such questions and susggestions are common at CO2.Earth.  They are all good questions, and they are related.  In response, this page points to some data and explanations about the posting of data for CO2 and other greenhouse gases (GHGs).  

First, CO2.Earth rarely receives requests to explain what CO2-eq is.  But that is a more basic question and very important if you are just being introduced to the concept of CO2 equivalent--or the related concept of global warming potential.  Plenty of good explanations are posted online.  These include pages at ecometrica.com (pdf version) and Wikipedia (CO2 equivalent + global warming potential).  

Returning to the questions about GHGs, we're talking about different numbers.  In this article, we'll look at how those numbers are obtained, what we can understand from them, and some of the purposes they can serve.  From there, it becomes of choice of what number or numbers we want to pay attention to at one time or another.

At CO2.Earth, the focus is obviously on carbon dioxide (CO2).  This is just one of more than a dozen greenhouse gases that enhance the warming of the Earth by trapping energy from the sun.   The global warming potential (GWP) of CO2 is not nearly as high as a number of other GHGs.  For example, methane (CH4) has a GWP at least 25 times that of CO2.  But CO2 emissions dwarf other greenhouse gases in terms of number of molecules.  Total warming from global CO2 emissions from humans (fossil fuel combustion mostly, as well as land use change and cement curing) makes CO2 our chief greenhouse gas.  It represents more than half the warming, and atmospheric increases is greater for CO2 than other greenhouse gases.  CO2 is the single biggest part of the problem, and it is the part of the problem that is growing the fastest.  I will go further and suggest that we aren't solving climate crisis if we aren't turning around the problem of CO2 rise in the atmosphere.  To do that, you gotta measure it, see it, and target it.  

CO2e includes CO2.  it has x.      there is the kyoto 6.  MIT 24.   purpose is that solving GHG involves all warming.  This is true,

My thing -- for ordinary people, is its a lot to understand each gas, its unique properties and sources, and so on.  


CO2.Earth is a gateway to understanding.  


So the focus is on this aspect. 


Should resources come available -- in the form of volunteers, articles suited to CO2.earth that we can post, funds to create what is not available, then we can build more connections for ordinary folks to learn about these things, and for policy makers to delve into issues while have a good grasp of the context and how earth systems fits and function together.  


GHGs are different causes.  Demand different solutions, sometimes overlapping. 








Yale Climate | Understanding Carbon Dioxide Equivalence

RealClimate | CO2 Equivalents



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