Removal of Legacy Climate Pollution

Posted By: Portland CCLon: February 27, 2026In: Citizen's Climate Lobby, Climate JusticeNo Comments

Removal of Climate Pollution

Not enough attention has been paid to addressing the problem of legacy pollution that has remained in the atmosphere for over 100 years. We climate advocates most often focus on reducing CO2 emissions and not enough on the mess already created.

This makes sense. After all, we want to stop the sources of damage. But the scientific community is turning our attention to the need to address the bigger problem. Namely, the almost 1 trillion tons of excess CO2 in the atmosphere, reported by the global average of 425 parts per million (over 40% higher than pre-industrial levels). This is what is causing the greenhouse effect, warming the planet, and causing climate disruptions.

Annually, we humans contribute about 40 billion tons of carbon into the atmosphere. Roughly half of this gets absorbed in the oceans or by plant life. So, the net addition is approximately 20 billion tons per year. The legacy excess content of CO2 is therefore over 40 times as much and it remains in the atmosphere for over 100 years. Here is a scale comparing new annual emissions to the legacy problem.

Legacy Climate Pollution - Atmospheric CO2 chart

Fortunately, there are many people engaged in scaling up strategies to remove and sequester CO2 durably.

These range from expensive techniques of Direct Air Capture and mineralization of CO2 to relatively inexpensive means of adding limestone to rivers, enhanced rock weathering, and methods that can boost agriculture naturally, like incorporating basalt, olivine dust, or biochar into farm soils to enhance output (and sequester carbon).

Overall, there are over 700 companies around the world that are competing to be first to develop feasible — and especially scalable — techniques of carbon capture, utilization, and storage.

It is arguably all the more important, now that the US government has abandoned any role in emissions reduction efforts, for us to put investment into cleaning the mess we have already created. Private investment is advancing.