Even educated experts are now pitching ideas straight out of science fictionReuters - Extreme weather, water shortages and imperiled polar bears: The effects of climate change are obvious and dire. To stem the tide — literally and figuratively — even educated experts are now pitching ideas straight out of science fiction.
These are the five most-discussed ideas in geoengineering to combat climate change:
1 - Fake a volcanic eruption
When particularly explosive volcanoes erupt, they blast ash and sulfuric acid droplets into the atmosphere, which then morph into tiny reflectors that shield Earth from the sun. The result of this natural cycle is a global cooling effect. To mimic this process, scientists have proposed injecting a layer of sulfur dioxide particles into the stratosphere, most likely via aircraft.
In abundance, however, these particles gradually chip away at the ozone layer, reducing its ability to absorb the sun’s rays and allowing dangerous radiation through. Another problem: Once injected, the particles tend to spread around the globe and linger for years, making the process hard to undo if things go awry.
2 - Make clouds brighter
Clouds keep things cool by reflecting the sun’s rays away from Earth. The whiter the cloud, the better it is at reflecting the sun. By seeding certain clouds with whitening materials — basically tiny particles of saltwater taken from the ocean below – we can transform them into natural sunshields.
But lowering temperatures by blocking the sun’s rays is not without problems. Reducing the heat from the sun also means less water from Earth’s surface evaporates back up into clouds. That means when the clouds drift toward other parts of the world as part of a normal weather pattern, areas expecting rain might not get it anymore.
3 - Fling a giant sunshield into space
You know those accordion-like sunshades made for car windows to keep the interior cool during summer? Scientists have proposed using that same principle to cool Earth. This technique would launch an enormous set of particle-based reflectors into space, positioning them between the sun and Earth to act as a giant parasol.
We know that this technique could cool Earth efficiently and relatively quickly, but the logistics and cost are serious obstacles.
4 - Scrub the air of CO2
The goal here is to separate CO2 molecules from the air by passing it through chemical filters of a sort, which absorb CO2. This technique actually makes a lot of sense if you’re trying to filter carbon dioxide from, say, the smoke stack of a coal plant before it gets released into the atmosphere. If you try grabbing air out of your backyard, however, things get tougher: only about half a percent of that air is CO2.
5 - Enrich the ocean with iron
Studies have shown that dumping iron dust into the ocean encourages the growth of blooms of phytoplankton — microscopic drifting plant life — that absorb atmospheric CO2 from the ocean. The hope is that after these tiny ocean plants die, they descend to the seafloor and take the carbon with them. The more phytoplankton, the more carbon they’ll pull down to the bottom, the thinking goes.
The problem is when phytoplankton sinks, other small ocean organisms consume and excrete them. This recirculates the carbon up to the ocean surface and ultimately back into the atmosphere as CO2.
So, yes, some of these ideas are bonkers and could potentially spark environmental issues much more atrocious than the ones we have now. But the fact that some of these are even on the table should be indicative of an even more terrifying reality: We need a solution to climate change, and we need one fast.