As we celebrated Earth Day on Thursday on April 22nd; many Americans have probably wondered if we’re able to reverse the clock on climate change.  The answer to that is yes, but we will not be able to stop the changes that are happening for the next several decades. Authors David Herring and Rebecca Lindsey from Climate. gov are saying that what we can do is try to “slow and limit the amount of global warming by reducing human emissions of heat-trapping gasses and black carbon (soot)”  Even if all human emissions of heat-trapping gases were to stop right now, the Earth’s temperature would continue to rise for a few decades because the ocean currents would still continue to bring back excess heat stored in the deep ocean back to the surface. Once the excess heat radiates out to space, the Earth’s temperature would have the chance to stabilize.

Alternative methods to slow and reduce global warming that has been proposed are known as “climate engineering”, or “geoengineering”.  One geoengineering proposal involves cooling the earth’s surface by injecting reflective particles into the upper atmosphere to scatter and reflect sunlight back to space.

Other proposals involve seeding the oceans with iron to stimulate large-scale phytoplankton blooms, drawing down carbon dioxide out of the atmosphere through photosynthesis. These methods could work, but many climate scientists oppose undertaking geoengineering until we have a much better understanding of the possible side effects. It is true that if we don’t take dramatic action in the next couple of decades, we would be unlikely to keep global warming below 2.7 Fahrenheit in this century.  The more we overshoot that threshold, the more serious and widespread the negative impacts will be, which means decisions on the best actions to take need to be made quickly.

For more information visit the NOAA Climate website.