A fierce scientific debate is unfolding over controversial climate technologies aimed at saving polar ice. While some researchers are pushing ahead with bold geoengineering experiments in the Arctic, and the focus should stay on cutting carbon emissions. 


Geoengineering plan sparks debate

On April 1, the Tennessee state House of Representatives passed a bill to prevent geoengineering. In geoengineering, the atmosphere is intentionally modified to counteract global warming.

On April 1, the Tennessee state House of Representatives passed a bill to prevent geoengineering. In geoengineering, the atmosphere is intentionally modified to counteract global warming. What does the bill cover? The bill targets various methods of geoengineering, including theoretical ideas about cooling the climate by solar radiation modification, cloud seeding, etc. Fact vs. fiction While the motive of the bill seems to be straightforward: to stop geoengineering, lawmakers discussed the proposal straddled between fact and fiction because most geoengineering options are theoretical and untested. Many of the concepts grouped together under the broad term "geoengineering" are little more than the wild notions that scientists created while trying to figure out how to slow down global warming. Some suggested that solar geoengineering projects are already underway and others referred to fears and misunderstandings that appeared to stem from the “chemtrails” conspiracy theory. “This will be my wife’s favourite bill of the year. She has worried about this, I bet, 10 years. It’s been going on a long, long time. If you look up — one day, it’ll be clear. The next day they will look like some angels have been playing tic-tac-toe. They’re everywhere. I’ve got pictures on my phone with X's right over my house. For years they denied they were doing anything,” Republican Sen. Frank Niceley said at a hearing about the bill last month. What is chemtrails theory? The chemtrails theory suggests that airplanes are not making trails of condensation known as contrails but instead disperse government-controlled chemicals. Despite its lack of scientific basis, variations of this theory have gained traction, with some suggesting it ties into weather and climate manipulation. However, experts dismiss these claims as conspiratorial nonsense. Anti-geoengineering policy wave Tennessee is not the only state to enact an anti-geoengineering policy. Illinois, Kentucky, Minnesota, New Hampshire, Pennsylvania, Rhode Island, and South Dakota have seen/introduced similar bills. The trend is emerging from a mix of conspiracy theories and concerns about the possibility of climate modification taking hold in the public consciousness. (With inputs from agencies)

US: Tennessee Senate passes bill banning geoengineering amid ‘chemtrails’ conspiracy theories

Dismissed a decade ago as far-fetched and dangerous, schemes to tame the effects of global warming by engineering the climate have migrated from the margins of policy debates towards centre stage.

"Plan A" refers to solving&nbsp;the problem at its source. But the UN's top climate science body has made it clear that slashing carbon pollution won't be enough to keep Earth from overheating. That has opened the door to a host of&nbsp;geoengineering&nbsp;schemes, from building underwater walls to shore up an Antarctic glacier the size of Britain to injecting a giant sunscreen into the stratosphere.

Here is a menu of "Plan B"&nbsp;geoengineering&nbsp;solutions, along with their potential drawbacks:

Direct CO2 capture&nbsp;

Experiments have shown it is possible to suck planet-warming carbon dioxide directly from the air, converting it into fuel pellets or storing it underground.

A company backed by Microsoft co-founder Bill Gates launched a pilot facility in Canada in 2015, and another company operates one in Iceland.

Drawback: The technology is currently prohibitively expensive and might take decades to operate at scale.

Solar radiation management

Unlike other strategies, solar radiation management does not target CO2. The goal is simple: prevent some of the sun's rays from hitting the planet's surface, forcing them back up into space.

One idea is to inject or spray tiny reflective particles into the stratosphere, possibly with balloons, aircraft or through giant tubes.

Nature sometimes does the same: Debris from the 1991 eruption of Mount Pinatubo in the Philippines lowered the planet's average surface temperature for a year or two afterwards.

Sixty-six million years ago, a ten-kilometre wide asteroid strike threw up so much debris that it wiped out land-based dinosaurs built for steamy tropical climes.&nbsp;

In April, a balloon test flight in Sweden for the Harvard-led project SCoPEx, short for "Stratospheric Controlled Perturbation Experiment", was postponed amid concerns over the implications for the environment and people in the country.&nbsp;&nbsp;

In Australia, trials of a controversial technique to spray microscopic salt crystals into the air above the threatened Great Barrier Reef to make the clouds brighter began last year.&nbsp;

Australian scientists say if successful and combined with other climate and protection measures this could help slow the decline of the reef.&nbsp;&nbsp;

Afforestation

Extensive planting of trees could significantly slow the concentration of CO2 in the atmosphere, which currently stands at more than 510 parts per million, 50 per cent more than 150 years ago.

Drawback: Even if deforestation could be reversed, more than 100,000 square kilometres of tropical forests have disappeared each year since 2013,&nbsp;the huge number of trees needed to put a dent in CO2 emissions would clash with food and biofuel crops.

BECCS&nbsp;

Bioenergy with carbon capture and storage (BECCS) marries a natural process with a high-tech one.&nbsp;

The first step is to plant rapeseed, sugarcane, corn or "2nd-generation" biofuel crops such as switchgrass, which pull CO2 from the air while growing. The second step is while burning the harvested plants for energy to sequester the CO2 produced.

In theory, the result is less CO2 in the atmosphere than when the process started. Virtually all climate change models projecting a future consistent with the Paris Agreement's temperature targets assume a key role for BECCS.

Drawback: Studies calculate that up to twice the area of India would need to be given over to biofuels, putting BECCS in conflict with food crops. Such schemes would also require vast amounts of freshwater.

Ocean fertilisation&nbsp;

Microscopic ocean plants called phytoplankton gobble up CO2 and drag it to the bottom of the ocean when they die. Their colony size is limited by a lack of natural iron, but experiments have shown that sowing the ocean with iron sulphate powder creates large blooms.

Drawbacks: Scientists worry about unintended impacts. Die-offs of plankton, for example, use up oxygen, which could create massive "dead zones" in the oceans, something already on the rise.

Enhanced weathering&nbsp;

Natural weathering of rocks removes about one billion tonnes of CO2 from the atmosphere every year, about two per cent of total man-made C02 emissions.&nbsp;

Spreading a powdered form of a greenish iron silicate called olivine across certain landscapes can mimic that process, experiments have shown.

Drawbacks: It would be expensive to mine and mill enough olivine to make a difference.

Biochar&nbsp;

Biochar is charcoal made by heating plant waste, rice straw, peanut shells, wood scraps, over long periods in low-oxygen conditions. It can store CO2 for long periods, and also enriches soil.

Drawback: The scientific jury is still out on how quickly this method could be scaled up, and on the stability of biochar used as a fertiliser.

(With inputs from agencies)

Dismissed a decade ago as far-fetched and dangerous, schemes to tame the effects of global warming by engineering the climate have migrated from the margins of policy debates towards centre stage.

Dismissed a decade ago as far-fetched and dangerous, schemes to tame the effects of global warming by engineering the climate have migrated from the margins of policy debates towards centre stage. "Plan A" refers to solving the problem at its source. But the UN's top climate science body has made it clear that slashing carbon pollution won't be enough to keep Earth from overheating. That has opened the door to a host of geoengineering schemes, from building underwater walls to shore up an Antarctic glacier the size of Britain to injecting a giant sunscreen into the stratosphere. Here is a menu of "Plan B" geoengineering solutions, along with their potential drawbacks: Direct CO2 capture Experiments have shown it is possible to suck planet-warming carbon dioxide directly from the air, converting it into fuel pellets or storing it underground. A company backed by Microsoft co-founder Bill Gates launched a pilot facility in Canada in 2015, and another company operates one in Iceland. Drawback: The technology is currently prohibitively expensive and might take decades to operate at scale. Solar radiation management Unlike other strategies, solar radiation management does not target CO2. The goal is simple: prevent some of the sun's rays from hitting the planet's surface, forcing them back up into space. One idea is to inject or spray tiny reflective particles into the stratosphere, possibly with balloons, aircraft or through giant tubes. Nature sometimes does the same: Debris from the 1991 eruption of Mount Pinatubo in the Philippines lowered the planet's average surface temperature for a year or two afterwards. Sixty-six million years ago, a ten-kilometre wide asteroid strike threw up so much debris that it wiped out land-based dinosaurs built for steamy tropical climes. In April, a balloon test flight in Sweden for the Harvard-led project SCoPEx, short for "Stratospheric Controlled Perturbation Experiment", was postponed amid concerns over the implications for the environment and people in the country. In Australia, trials of a controversial technique to spray microscopic salt crystals into the air above the threatened Great Barrier Reef to make the clouds brighter began last year. Australian scientists say if successful and combined with other climate and protection measures this could help slow the decline of the reef. Afforestation Extensive planting of trees could significantly slow the concentration of CO2 in the atmosphere, which currently stands at more than 510 parts per million, 50 per cent more than 150 years ago. Drawback: Even if deforestation could be reversed, more than 100,000 square kilometres of tropical forests have disappeared each year since 2013, the huge number of trees needed to put a dent in CO2 emissions would clash with food and biofuel crops. BECCS Bioenergy with carbon capture and storage (BECCS) marries a natural process with a high-tech one. The first step is to plant rapeseed, sugarcane, corn or "2nd-generation" biofuel crops such as switchgrass, which pull CO2 from the air while growing. The second step is while burning the harvested plants for energy to sequester the CO2 produced. In theory, the result is less CO2 in the atmosphere than when the process started. Virtually all climate change models projecting a future consistent with the Paris Agreement's temperature targets assume a key role for BECCS. Drawback: Studies calculate that up to twice the area of India would need to be given over to biofuels, putting BECCS in conflict with food crops. Such schemes would also require vast amounts of freshwater. Ocean fertilisation Microscopic ocean plants called phytoplankton gobble up CO2 and drag it to the bottom of the ocean when they die. Their colony size is limited by a lack of natural iron, but experiments have shown that sowing the ocean with iron sulphate powder creates large blooms. Drawbacks: Scientists worry about unintended impacts. Die-offs of plankton, for example, use up oxygen, which could create massive "dead zones" in the oceans, something already on the rise. Enhanced weathering Natural weathering of rocks removes about one billion tonnes of CO2 from the atmosphere every year, about two per cent of total man-made C02 emissions. Spreading a powdered form of a greenish iron silicate called olivine across certain landscapes can mimic that process, experiments have shown. Drawbacks: It would be expensive to mine and mill enough olivine to make a difference. Biochar Biochar is charcoal made by heating plant waste, rice straw, peanut shells, wood scraps, over long periods in low-oxygen conditions. It can store CO2 for long periods, and also enriches soil. Drawback: The scientific jury is still out on how quickly this method could be scaled up, and on the stability of biochar used as a fertiliser. (With inputs from agencies)

Here are some climate engineering schemes that can act as 'Plan B' for Earth

geoengineering

Geoengineering, News on Geoengineering, stories on Geoengineering, articles on Geoengineering, Geoengineering stories at Wion, Geoengineering news, Geoengineering latest news