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We need to leave all options on the table to combat climate change. That includes geoengineering – methods to reverse the damage that we’ve already done to the environment. These techniques don’t work as a replacement to moving to renewable energy, but we should investigate geoengineering in case we can’t change our behaviors fast enough to ward off the worst of climate change.

In general, geoengineering methods fall into two categories (though there are ideas that don’t fit into either one): 

1) Carbon dioxide removal – techniques that remove the amount of carbon dioxide in the air.

2) Solar radiation management – techniques that decrease the amount of sunlight that hits the atmosphere or reflects more of it back into space. 

Certain geoengineering options are easy to reverse, or benign enough that we can feel safe deploying them without much further testing. For example, planting millions of new trees would store large amounts of carbon. Ethiopia recently planted 350 million new trees, and more countries can engage in similar projects. We should also engage in ocean afforestation, seeding the oceans with microalgae.

Additional carbon capture technologies can help us to remove a lot of the carbon from the air, a process that we know is safe because trees have been doing it for longer than humans have existed. Not only that, but scientists largely agree that technologies in this area must be a part of any climate program.

Different organizations are researching the use of carbon capture to create building materials, carbon-neutral fuels (e.g., BECCS), and even ethanol. The federal government should encourage this research while still ensuring certain safety guidelines. We can also use this captured carbon to improve our soil (e.g., biochar). We can also take smaller steps, like packing gravel against the bases of glaciers to slow down their melting.

While carbon capture solutions are important to investigate and can bend the curve to give us more time or serve as a partial solution to the climate crisis, we should also prepare for the worst. There are feedback loops that we don’t understand that could quickly lead to a catastrophic event. If it comes to that, we need to be prepared with options like solar radiation management that have potential side effects that are more desirable than the alternative: climate collapse.

The safest forms of solar radiation management include a technique of spraying salt water into clouds makes them larger and brighter, which will reflect more sunlight into space. There are also more extreme options of solar radiation management that include space mirrors (yes, space mirrors) and stratospheric aerosol scattering.

Space mirrors would involve launching giant foldable mirrors into space that would deploy and reflect much of the sun’s light. This method would be extremely expensive, which is why it should be investigated as a last resort. However, since we would be able to “undo” the mirror after deployment if needed, it’s less permanent.

Stratosphere aerosol scattering, on the other, would be a drastic response to the climate crisis. When volcanoes erupt, they spew sulfur dioxide into the sky and reflect sunlight particles away from the earth. The massive eruption of Mt. Pinatubo in 1991 was recorded to help push global temperatures down half a degree over the following 2 years. If scientists can find a way to burn sulfur in the stratosphere, then they could mimic the positive effects of volcanoes eruptions on climate change and their ability to help keep the earth cool.  Bill Gates has recently backed a study to explore the feasibility of this method, but there are many dangers to it, which is why it (and other, similar methods) require research.

If we don’t start experimenting with these methods, then someone else will. Let’s be a world leader in geoengineering so that we can ensure it’s safe and scalable, and that we’re in charge of deploying it, should the need arise.

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Problems to be Solved

  • As the climate continues to change, reaching net-zero emissions will not be enough to prevent catastrophic effects on our environment.
  • We do not currently have the technology or ability in place to reverse climate change.

Help make this idea a reality.

We’ve already done a lot of damage to the environment. Glaciers and ice sheets have melted and greenhouse gases have accumulated in the atmosphere. To accept these as irreversible is to accept limitations to human ingenuity that I don’t believe are true. Our scientists were able to unlock the power of the atom; they can also find ways to reverse the damage done to our world.
  • Develop backup plans for combating climate change if net-zero emissions proves to not be enough
  • Consider and investigate all possible options to reverse climate change to ensure we are ready to employ these methods if they become necessary

As President, I will...

  • Provide $800 million to NASA, the Department of Defense, and NOAA to research, experiment with, and test geoengineering methods that will either give us more time to deal with climate change, or give us options should we hit a climate tipping point of which we aren’t aware.
  • Convene a global summit on geoengineering. Many researchers in the US and other countries are doing work in this field – if we bring them together we can formalize and accelerate our learning and build a global approach. 
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