The problem with “percentage”

One of the readers of my columns in Pollution Engineering dismissed the significance of climate change by citing that CO2 only makes up 0.006 percent of the atmosphere. The flaw with such argument is that the ecosystem can react to a seemingly small percentage increase in pollutants globally.

Take the phenomenon of El Niño as an example. El Niño can be caused by a very small increase in the surface temperature of parts of the ocean. As we know, it could lead to unusual floodings and droughts in parts of the world.

CO2 is not a toxic pollutant like dioxin or PCB. But a small increase of CO2 in the atmosphere can have dire consequences that will upset the ecological balance and the weather pattern. As my earlier “bullet in the head” example shows, it is not the weight of the bullet that kills the person. It is the introduction and placement of the bullet. 

Another reader wrote to me and told me that CO2 is NOT a pollutant. Well – he is wrong. The US Supreme Court has ruled that CO2 is a pollutant under the Clean Air Act and it directed EPA to determine if this pollutant poses a threat to human health. The court also told EPA that if the agency determines that CO2 endangers human health, then it must regulate it as mandated by the Clean Air Act. 

It was because of this Supreme Court ruling that EPA conducted its draft greenhouse gas endangerment study. The comment period for this draft has expired and we are awaiting EPA’s final findings.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s