schemes

Fertilizing The Ocean | Earth Wise

January 23, 2023 By EarthWise Leave a Comment

There are a variety of schemes for removing carbon dioxide from the atmosphere. Some require advanced and generally not-very-well developed technology. Others, such as planting vast numbers of trees, are nature-based but are daunting with respect to the scale to which they need to take place in order to be truly effective.

Researchers at the Pacific Northwest National Laboratory in Richland, Washington have been examining the scientific evidence for seeding the oceans with iron-rich engineered fertilizer in order to feed phytoplankton. Phytoplankton are microscopic plants that are a key part of the ocean ecosystem.

Phytoplankton take up carbon dioxide as they grow. In nature, nutrients from the land end up in the ocean through rivers and from blowing dust. These nutrients fertilize the plankton. The idea is to augment these existing processes to increase the growth of phytoplankton. As they eventually die, they sink deep into the ocean, taking the excess carbon with them.

The researchers argue that engineered nanoparticles could provide highly controlled nutrition that is specifically tuned for different ocean environments. Surface coatings could help the particles attach to plankton. Some could be engineered with light-absorbing properties, allowing plankton to consume and use more carbon dioxide.

Analysis of over 100 published studies showed that numerous non-toxic, abundant, and easy-to-create metal-oxygen materials could safely enhance plankton growth. According to the researchers, the proposed fertilization would simply speed up a natural process that already sequesters carbon in a form that could remove it from the atmosphere for thousands of years. They argue that given the current trends in the climate, time is of the essence for taking action.

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Fertilizing the Ocean to Store Carbon Dioxide

Photo, posted August 2, 2007, courtesy of Kevin McCarthy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Side Effects Of Geoengineering | Earth Wise

July 20, 2020 By EarthWise Leave a Comment

As the world struggles to reduce the greenhouse gas emissions that are warming the global climate, some researchers are exploring proposals to deliberately engineer climate changes to counteract the warming trend. One of the most widely discussed approaches is to shade the Earth from a portion of the sun’s heat by injecting the stratosphere with reflective aerosol particles. Proponents of this idea point out that volcanoes do essentially the same thing, although generally for only a limited amount of time. Particularly large eruptions, such as the Krakatowa eruption of 1883, wreaked havoc with weather around the world for an entire year.

Schemes to launch reflective aerosols – using planes, balloons, and even blimps – appear to be quite feasible from the standpoint of physically accomplishing them. But this says nothing about the political, ethical, and societal issues involved. The point is that such an approach could indeed lower global temperatures and thereby potentially offset the warming effects of greenhouse gases.

A study by scientists at MIT looked at what other effects such a solar geoengineering project might have on the climate. Their modeling concluded that it would significantly change storm tracks in the middle and high latitudes. These tracks give rise to cyclones, hurricanes, and many more ordinary weather phenomena.

According to the study, the northern hemisphere would have weakened storm tracks, leading to less powerful winter storms, but also stagnant conditions in summer and less wind to clear away air pollution. In the southern hemisphere, there would be more powerful storm tracks.

Aside from turning the world’s weather patterns inside out, solar geoengineering would do nothing to address the serious issue of ocean acidification caused by increasing carbon dioxide levels.

As many have pointed out, playing the geoengineering game would have many unintended consequences.

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Study: Reflecting sunlight to cool the planet will cause other global changes

Photo courtesy of MIT.

Earth Wise is a production of WAMC Northeast Public Radio.

Geoengineering And Developing Countries

June 21, 2018 By EarthWise Leave a Comment

There are some mind-boggling schemes being discussed to mitigate the global warming caused by greenhouse gases. These include placing giant mirrors in orbit to reflect sunlight before it reaches Earth and launching millions of tons of sulfur into the stratosphere to simulate the effects of a major volcanic eruption.