<story><title>Turning CO2 to Stone</title><url>http://sciencebulletin.org/archives/6839.html</url></story><parent_chain></parent_chain><comment><author>owenversteeg</author><text>I was curious, so I did the math.&lt;p&gt;Total worldwide carbon production is 38.2 billion tons per year. Cost to sequester a ton of carbon is between $30 and $150, depending on who you ask and how you do it. Let&amp;#x27;s assume a middle of the road price of $90&amp;#x2F;ton. That&amp;#x27;s $3.438 trillion a year, or about $478 per person. This is roughly equal to the US yearly federal spending, or 3% of the world GDP.&lt;p&gt;If you somehow pooled together all the world&amp;#x27;s billionaires and got them to contribute their annual income (roughly $600 billion a year, averaging the past 7 years) to the effort, you could eliminate roughly 20% of carbon produced in the world every year.&lt;p&gt;-------------------------&lt;p&gt;Suddenly, it becomes crystal clear why finding new sequestration methods is incredibly important: if you can get the cost from $160 to $10 per ton, then suddenly all you&amp;#x27;d need would be a coalition of half the world&amp;#x27;s billionaires to stop the main cause of global warming.&lt;p&gt;Additionally, it&amp;#x27;s important that people realize that CO2 production is in tons of CO2 per year. Tree offsets are a one-time deal, since when trees die they release CO2, and when new ones are born they absorb that CO2 again. After they&amp;#x27;ve been planted, forests are generally carbon neutral. That&amp;#x27;s why we can&amp;#x27;t &amp;quot;just plant trees&amp;quot;: we&amp;#x27;d have to be continuously planting new trees. The Earth is only 8% arable land, much of which already has stuff on it, or is undesirable for one reason or another. We&amp;#x27;d run out of space pretty fast. Trees are good for other reasons: preventing climate change (different from global warming), preserving species diversity, being nice to look at, etc etc.&lt;p&gt;-------------------------&lt;p&gt;Mostly off-topic: when I was looking at estimates of land size, apparently the amount the US has shrunk from 2007 to 2015 (14,000 km2; went from 9,161,120 km2 to 9,147,420 km2)  [0] is roughly equivalent to half the area of the Netherlands. Wow.&lt;p&gt;[0] &lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;data.worldbank.org&amp;#x2F;indicator&amp;#x2F;AG.LND.TOTL.K2&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;data.worldbank.org&amp;#x2F;indicator&amp;#x2F;AG.LND.TOTL.K2&lt;/a&gt;</text></comment>
<story><title>Turning CO2 to Stone</title><url>http://sciencebulletin.org/archives/6839.html</url></story><parent_chain></parent_chain><comment><author>VeejayRampay</author><text>It&amp;#x27;s nice that we&amp;#x27;re looking to alternative ways to capture and store atmospheric CO2, but at time it also does look like we&amp;#x27;re working too hard to replicate a system that does that already (and has for a long time): plants.&lt;p&gt;Or does it mean that the time of planting trees and preserving forests is over now and we have to do it another (most often less efficient) way?</text></comment>