ED:  These numbers are different than other IPCC and the net accumulation is not shared by many.  Perhaps because they have been changed like other parameters to fit the narrative.  The IPCC estimates are much higher than other scientisits who are not a part of AGW.  Comments about Carbon 14 are also not shared universally, for Carbon 14 is generated naturally and is unstable.

Climate myths: Human CO2 emissions are too tiny to matter

The emissions for ACO2 range from 5.5Gtons to 32Gtons.   In essence there is the amount that makes it into the atmosphere around 40% less than that emitted.   So why are the other numbers so high?  I have to find out.  

By Catherine Brahic

New Scientist Article

 

 

Ice cores show that carbon dioxide levels in the atmosphere have remained between 180 and 300 parts per million for the past half-a-million years. In recent centuries, however, CO2 levels have risen sharply, to at least 380 ppm (see Greenhouse gases hit new high)

 

So what’s going on? It is true that human emissions of CO2 are small compared with natural sources. But the fact that CO2 levels have remained steady until very recently shows that natural emissions are usually balanced by natural absorptions. Now slightly more CO2 must be entering the atmosphere than is being soaked up by carbon “sinks”.

 

The consumption of terrestrial vegetation by animals and by microbes (rotting, in other words) emits about 220 gigatonnes of CO2 every year, while respiration by vegetation emits another 220 Gt. These huge amounts are balanced by the 440 Gt of carbon dioxide absorbed from the atmosphere each year as land plants photosynthesise.

 

Similarly, parts of the oceans release about 330 Gt of CO2 per year, depending on temperature and rates of photosynthesis by phytoplankton, but other parts usually soak up just as much – and are now soaking up slightly more.

 

Ocean sinks

Human emissions of CO2 are now estimated to be 26.4 Gt per year, up from 23.5 Gt in the 1990s, according to an Intergovernmental Panel on Climate Change report in February 2007 (pdf format).   Disturbances to the land – through deforestation and agriculture, for instance – also contribute roughly 5.9 Gt per year.

 

About 40% of the extra CO2 entering the atmosphere due to human activity is being absorbed by natural carbon sinks, mostly by the oceans.  The rest is boosting levels of CO2 in the atmosphere.

 

How can we be sure that human emissions are responsible for the rising CO2 in the atmosphere?  There are several lines of evidence. Fossil fuels were formed millions of years ago. They therefore contain virtually no carbon-14, because this unstable carbon isotope, formed when cosmic rays hit the atmosphere, has a half-life of around 6000 years.

So a dropping concentration of carbon-14 can be explained by the burning of fossil fuels. Studies of tree rings have shown that the proportion of carbon-14 in the atmosphere dropped by about 2% between 1850 and 1954.  After this time, atmospheric nuclear bomb tests wrecked this method by releasing large amounts of carbon-14.

 

Volcanic misunderstanding

Fossil fuels also contain less carbon-13 than carbon-12, compared with the atmosphere, because the fuels derive from plants, which preferentially take up the more common carbon-12.  The ratio of carbon-13 to carbon-12 in the atmosphere and ocean surface waters is steadily falling, showing that more carbon-12 is entering the atmosphere.

 

Finally, claims that volcanoes emit more CO2 than human activities are simply not true. In the very distant past, there have been volcanic eruptions so massive that they covered vast areas in lava more than a kilometre thick and appear to have released enough CO2 to warm the planet after the initial cooling caused by the dust (see Wipeout).  But even with such gigantic eruptions, most of subsequent warming may have been due to methane released when lava heated coal deposits, rather than from CO2 from the volcanoes (see also Did the North Atlantic’s ‘birth’ warm the world?).

Measurements of CO2 levels over the past 50 years do not show any significant rises after eruptions.  Total emissions from volcanoes on land are estimated to average just 0.3 Gt of CO2 each year – about a hundredth of human emissions (pdf document).

 

While volcanic emissions are negligible in the short term, over tens of millions of years they do release massive quantities of CO2. But they are balanced by the loss of carbon in ocean sediments subducted under continents through tectonic plate movements. Ultimately, this carbon will be returned to the atmosphere by volcanoes.

 

Section for a video or follow-on comment

We should revisit occasionally what the proper role of government is.   As the constitution was a good sense of direction, we need a core set of principles to add in order to deal with the future.

 

So many want to engineer society, remove risk, assist certain groups, rather than let individuals thrive and raise communities.  Why?

 

Is Democracy where we all "get it good and hard" or is it the best means to a free society?

 

Should we roll with the special interests, or make the government achieve its proper role, what is that role, and how to do this?

 

When do deficits and governments become too large?

 

Government is becoming more elitist while trying to sell corrections to problems it created, what makes this possible?

 

Could include a pic

This could also be inserted into the field above, or erased

 

Currently as a society, we are having a most difficult time discussing political issues.  What is driving this?   And why a rebirth in political culture would be a good thing.

 

Market Economy

Are "markets" dead as some would conjecture? Or is free enterprise what got us here?

 

Economic Theories

At the heart of economics there are several possible economic schools of thought, the essence of these schools of thought and how they relate to our lives.

  

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