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Renegade geoengineering

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As the dangers of climate change continue to grow, so has interest in geoengineering – deliberate tinkering with the earth’s climate system.  In particular, stratospheric solar geoengineering – releasing aerosols into the stratosphere to reduce the amount of heat from the sun reaching the Earth – is attracting increasing interest.  Scientists at Harvard, Cornell, Colorado State, Princeton, and the University of Chicago are all researching the topic.

Actually doing it on a scale that matters is fraught with peril from unintended consequences of disrupting the delicate interactions between the Earth’s atmosphere, ocean, land, and sea ice. 

Meanwhile, a tiny start-up company in Silicon Valley has raised more than a million dollars in venture capital and is busy releasing balloons full of sulfur dioxide into the atmosphere in the name of combatting global warming.  Furthermore, they are selling so-called “cooling credits” to customers who want to offset their personal carbon emissions.

The aerosol being released is on such a small scale that it can’t possibly have a meaningful effect on temperatures.  There really isn’t scientific analysis guiding or accompanying the work. 

There are no laws prohibiting the dispersal of small amounts of sulfur dioxide in California.  Even if there were, these people could go offshore or elsewhere to do their work.  But this renegade geoengineering highlights a serious issue; namely, that there doesn’t have to be scientific, political, or any other kind of consensus for someone to undertake a potentially catastrophic attempt to alter the climate.  It’s a real worry.

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Silicon Valley Renegades Pollute the Sky to Save the Planet

Photo, posted September 24, 2006, courtesy of Doc Searls via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Geoengineering could create winners and losers

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Geoengineering – deliberate interventions to alter the climate and curb climate change – is a controversial topic, to say the least.  Once practically considered taboo even to discuss, there in increasing interest in at least exploring various ideas about how to halt or reverse climate change through direct actions that impact global temperatures.

Putting aside the very real concerns about the risks and dangers associated with such action, there is also the issue that climate interventions may create dramatically different effects across the globe, benefitting some areas and adversely affecting others.

A recent study by scientists at Rutgers University tackled this very issue.  Published in the journal Nature Food, it described the results of computer models simulating the impacts of stratospheric aerosol intervention (SAI), which is spraying sulfur dioxide into the stratosphere, where it would partially shield the Earth from the Sun, lowering temperatures.

The study looked at 11 different SAI scenarios and found that none of them benefitted everyone.  Uncontrolled global warming favors crop production in cold, high-latitude areas such as Canada, Russia, Scandinavia, and our northern border states.  Moderate amounts of SAI favors food production in the mid-latitudes (such as in the US and Europe.)  Large amounts of intervention favors agricultural production in the tropics. 

Even if geoengineering might not have dire consequences – which is by no means certain – it would create winners and losers.  Nations may have different ideas of what constitutes an optimal global temperature.  So, who gets to decide where to set the global thermostat?  The prospects for conflict loom large. 

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Climate Intervention Technologies May Create Winners and Losers in World Food Supply

Photo, posted November 18, 2021, courtesy of Conall via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Scientists Call For Geoengineering Research | Earth Wise

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A group of more than 60 climate researchers has published an open letter calling for accelerated research into what is called solar radiation management.  This means changing the amount of solar energy reaching the surface of the earth by adding various substances into the stratosphere or into the clouds in order to help cool down the planet.

This form of geoengineering is controversial to say the least.  While such approaches would most likely be successful in cooling things down, such climate manipulation could have dangerous and unexpected consequences.

For their part, the scientists explicitly state that they do not support the use of solar radiation management or SRM.  Their position is that our current level of knowledge is not sufficient to accurately assess potential risks and consequences.  What they are advocating is for scientific research to be conducted to support the assessment of the potential effectiveness of various SRM techniques, to determine how these techniques would affect climate change under various greenhouse gas scenarios, and to determine the capabilities for detecting and attributing possible impacts of SRM interventions.

The letter was a response to a larger group of scientists and academics who called for a strict ban on geoengineering, saying that it could divert attention and resources from much-needed greenhouse gas reductions.  The new letter claims that gaining additional knowledge about SRM is a critical part of making effective and ethical decisions about its implementation.  They state that we have no right to ban the ability to search for a solution to the mess we created.

Opponents of such research are concerned that even pursuing it normalizes in the public eye what could potentially be a catastrophically dangerous activity.

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60 Scientists Call for Accelerated Research Into ‘Solar Radiation Management’ That Could Temporarily Mask Global Warming

Photo, posted February 11, 2006, courtesy of Janice Waltzer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Space Tourism And The Climate | Earth Wise

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Space tourism is human space travel for recreational purposes.  A few well-known billionaires have taken rocket rides in recent years and at least a dozen companies are at the vanguard of what they are expecting to be a burgeoning industry.  If space tourism truly takes off – pun intended – it could be a serious threat to the climate and the environment.

Black carbon – essentially soot – is emitted when fossil fuels, including rocket fuels, are burned.  Black carbon absorbs light from the sun and releases thermal energy, making it a powerful climate warming agent.  At lower altitudes, black carbon quickly falls from the sky, remaining in the atmosphere for only a matter of days or weeks.

Rockets are another story entirely.  They dump black carbon into the stratosphere as they blast into space, and up there black carbon is 500 times worse for the climate and sticks around for several years.

A detailed study by researchers at University College London looked at the climate impact of present-day space launches compared with the potential massive expansion of launches from a large space tourism industry.

The overall result is that current space launches are not a significant source of emissions, but space launches would become incredibly significant if projections of tourist space flights proved to be true.  Currently, there are roughly 100 space launches a year world-wide.  If that number becomes thousands, the impact on the climate would be substantial.

The same researchers looked at the ozone impact of rocket launches and reached a similar conclusion.  The current impact of spaceflights is not very significant, but a massive increase in launches could have a major impact on atmospheric ozone concentrations.

Space tourism may be exciting, but it also could be very dangerous for the planet.

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Space Tourism Poses a Significant ‘Risk to the Climate’

Impact of Rocket Launch and Space Debris Air Pollutant Emissions on Stratospheric Ozone and Global Climate

Photo, posted May 30, 2020, courtesy of Daniel Oberhaus (2020) via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wildfires And The Climate | Earth Wise

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Scientists from the National Center for Atmospheric Research recently published a study analyzing the events that influenced the world’s climate in 2020.  Among these were the pandemic-related lockdowns that reduced emissions and resulted in clearer air in many of the world’s cities.

While this was a significant event, the study found that something entirely different had a more immediate effect on global climate:  the enormous bushfires that burned in Australia from late 2019 to 2020, producing plumes of smoke that reached the stratosphere and circled much of the southern hemisphere.

Those fires sprung up in September 2019 and lasted until March 2020.  The fires burned more than 46 million acres (about 72,000 square miles), which is roughly the same area as the entire country of Syria.  Thousands of homes and other buildings were lost.

Major fires inject so many sulfates and other particles into the atmosphere that they can disrupt the climate system, push tropical thunderstorms northward from the equator, and potentially influence the periodic warming and cooling of tropical Pacific Ocean waters known as El Nino and La Nina.

According to the study, the COVID-19 lockdowns actually had a slight warming influence on global climate, as a result of clearer skies enabling more heat to reach the earth’s surface.  In contrast, the Australian bushfires cooled the Southern Hemisphere because the atmospheric particles reflected some of the incoming solar radiation back to space.

This summer, there have been raging wildfires in the western US and Canada, which have affected air quality in many parts of the nation and have been a serious health hazard.  Undoubtedly, these fires are influencing the climate system as well in ways that we are still trying to understand.

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Bushfires, not pandemic lockdowns, had biggest impact on global climate in 2020

Photo, posted January 18, 2020, courtesy of BLM-Idaho via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fire-Driven Thunderstorms

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In 2016 and 2017, wildfires in western Canada spawned thunderstorms that ignited additional fires, in some cases tens of miles away from the original fire.  These fire-triggered thunderstorms are technically known as pyrocumulonimbus clouds, or “pyroCb’s”.

The physics of pyroCb’s is complex.  When super-heated updrafts from an intense fire suck smoke, ash, burning materials, and water vapor high into the air, these elements cool and form so-called fire clouds that look and act like the cumulonimbus clouds associated with classic thunderstorms.  What is different is that the heat and particulates in the smoke almost always arrest the ability of the cloud to produce rain.  Instead, what remains is a lightning storm that moves across the landscape, triggering more fires.

These PyroCb events appear to be happening far more often, producing more energy, and erupting in places where they have never been seen before.  As the world warms, wildfires themselves are becoming larger and hotter.  In the past decade, wildfires have been burning more than twice as many acres as they did before the turn of the 21st century.  Along with the growth in wildfire activity, there has been an increase in PyroCb events, and there are now an average of 25 per year in western North America.

Apart from starting new fires, pyroCb’s also have similar effects as moderate-sized volcanic eruptions.  Smoke and aerosols from wildfires can rise high into the stratosphere, where they can linger for months.  Eventually, the particles carried aloft in the atmosphere do come down, dumping dangerous chemicals on far flung regions of the earth.  But unlike volcanic eruptions, which are relatively rare events, pyroCb’s are happening more and more each year.

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Fire-Induced Storms: A New Danger from the Rise in Wildfires

Photo, posted July 31, 2013, courtesy of Loren Kerns via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Geoengineering And Developing Countries

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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.

[Read more…] about Geoengineering And Developing Countries

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