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Technology or natural solutions: what’s our best bet for fighting climate change?



Humanity is currently facing some of its greatest challenges to date. We are witnessing debilitating droughts and ravaging wildfires, destructive floods and the loss of biodiversity — all things scientists have said for decades would happen due to our greenhouse gas emissions.

Apocalypse Plan B, a documentary from The Nature of Things, investigates some of the methods scientists are considering to slow down climate change, limit the damage that’s already done and cool the planet.

Dimming the sun by adding more gas to the atmosphere

David Keith is a Canadian professor of applied physics at Harvard University. He’s developed a strategy that could decrease the sun’s impact on Earth in an effort to keep us cool.

It’s based on the “volcano effect,” which happens when large volcanic eruptions spew tonnes of polluting gases like sulphur into the atmosphere. Gas particles that make it high into the atmosphere actually block some of the sun’s rays from reaching Earth’s surface, creating a surprising cooling effect.


Keith’s idea: intentionally release tonnes of sulphur gas into the stratosphere using aircraft. “It turns from a gas into little tiny particles, and those particles reflect away sunlight and can cool the planet a little bit,” he says in the documentary.

This isn’t a one-time fix. “We would have to start by putting 20,000 tonnes of sulphur in the stratosphere the first year,” Keith says in a talk featured in the film. “After 50 years, we’d be putting a million tonnes a year of sulphur in the stratosphere.”

Keith is quick to point out that this proposal only helps to cool the planet slightly while we still tackle the underlying problem of our emissions. “If anybody thinks this is a way to solve the problem of putting out CO2, they’re insane,” he says in the film.


Dimming the sun by adding more gas to the atmosphere | Apocalypse Plan B

This scientist has a proposal to fight climate change: intentionally release tonnes of sulphur gas into the stratosphere using aircraft, to dim the sun’s rays.

Some scientists are worried by the idea. “We can see that [dimming the sun] actually disrupts plant productivity because you change the distribution of sunlight,” says climate scientist Michael Mann. “That can end up shifting ocean currents and atmospheric wind patterns.”

Brightening clouds using fleets of autonomous ships

Sarah Doherty, a senior research scientist with the University of Washington’s department of atmospheric sciences, has her head in the clouds.

“Clouds are a really critical part of the climate system,” she explains in the documentary. “One of the factors that controls the temperature of the planet is how much cloud cover we have.”

Clouds work to reflect sunlight back out into space, and the whiter and brighter the clouds, the more sunlight is reflected. Doherty’s found that the more cloud cover we have, particularly low cloud cover, the cooler our planet. She’s been researching how we might brighten clouds over the oceans by using sea salt to enrich marine clouds.

In Australia, one team has put Doherty’s theory to the test. “We showed that it’s technically feasible to pump sea water and atomize it into trillions per second of tiny little sea water droplets,” says Daniel Harrison, an oceanographer and engineer at Southern Cross University. They are interested to see how the technology could help the Great Barrier Reef, which has experienced numerous mass bleaching events in recent years due to warming oceans. “In theory, [those droplets] can go on to help brighten clouds and cool the reef.”

A computer graphic of autonomous ships spraying sea water vapor into the air.
To brighten clouds on a large scale would take a lot of autonomous ships patrolling ocean regions and responding to weather conditions. (Grand Passage Media)

But to brighten clouds on a large scale would take ships — a lot of ships — to make an impact. “You would need thousands,” says Doherty. She envisions an autonomous fleet that would run on renewable energy, patrol specific ocean regions and respond to weather conditions.

Capturing carbon and storing it underground

Carbon capture is an attractive technology for the oil, gas, cement and steel industries, which are among the biggest emitters. It allows them to sequester much of the CO2 that’s produced by their operations, compress and liquify it, and pump it underground instead of releasing it to the air.

“Carbon capture and sequestration is very seductive,” says Mann. “[It] sounds like we can continue to burn fossil fuels and not worsen the climate crisis.”

But he’s quick to point out that there are still carbon emissions being released into the atmosphere. “In the very best cases, these plants capture maybe 70, maybe 80 per cent of the carbon pollution they generate.”

So what can be done about the carbon that’s accumulating in the atmosphere over time?

Direct air capture may offer a solution. This technology uses giant fans like a big vacuum, sucking up air and filtering out the CO2.

“We extract CO2 from the air and permanently remove it by storing it underground in rock formations,” says Jan Wurzbacher of Climeworks, an Iceland-based carbon capture company that isn’t associated with the fossil fuel industry.

Currently, their plant uses only green energy to remove an amount of carbon equivalent to what’s emitted by 870 cars every year. But the company has ambitious plans to remove one gigatonne every year — just over the amount that humans emit every month — by 2050.

“It’s not as invasive and dangerous as some of the other technologies that are being talked about,” says Mann. “[But] you’re trying to put the genie back in the bottle, and that’s difficult to do.”

Harnessing Earth’s very own carbon capture technology: forests

The Earth has seen huge climate fluctuations over its 4.5 billion-year history. Over time, the climate stabilized, and the planet’s animal and plant life began to recycle carbon in a balanced way.

One of the best examples of this all-natural carbon capture technology? Trees.

“I’d estimate that this tree stores about 5,000 kilograms of carbon,” says Lola Fatoyinbo in the film as she examines just one tree in a forest. “That’s five tonnes of carbon.”

Fatoyinbo is a research scientist with NASA’s biospheric sciences lab, and she studies forest ecosystems from space. In Fatoyinbo’s research, she uses data gathered from instruments on the International Space Station to map the density of the world’s forests, understanding their role in fighting climate change and how much CO2 they can remove from the atmosphere each year.


Every spring and summer, toxic rivers of CO2 are removed from our atmosphere – thanks to trees and plants | Apocalypse Plan B

16 days ago

Duration 1:13

Lola Fatoyinbo is a NASA research scientist who studies forest ecosystems from space. Using data gathered from instruments on the space station, she’s able to map the world’s forests, and the effect they have on our planet.

“Restoration of mangroves, forests and wetlands — these are really important mechanisms that are part of our fight,” says Fatoyinbo.

Rethinking farming

Gabrielle Bastien holds up a single clump of soil. “[This clump] contains more microorganisms than there are humans on this Earth.” Bastien is the founder of Regeneration Canada, part of a global movement among farmers to change how we grow our food.

“It’s a whole ecosystem in there,” she says in the documentary. Today’s common farming practices, however, lead to soil degradation — one of the biggest contributors to climate change.

“Soils are actually the largest terrestrial carbon sink,” says Bastien. “Aside from oceans, they contain the largest reserve of carbon on Earth.” When that rich, biodiverse soil ecosystem is disrupted by plowing and tilling, its carbon content is largely emitted to the atmosphere.

In Apocalypse Plan B, Bastien visits Sebastien Angers, a farmer who is doing things a little differently. He’s adopted regenerative farming practices that mimic nature, such as using  a no-till drill to plant seeds and seeding a variety of crops in the same field so they can nourish each other. “If you think of a natural ecosystem, it’s a very biodiverse system,” he says.

Angers also uses cover crops to shade the soil. This helps keep the earth moist and cool, increases the diversity in his fields and reduces the need for pesticides.

“We need this richness,” says Angers. “If you plow, you lose that. This field [took] 15 years to get this earthworm, fungi richness. It’s really long to build, really easy to destroy.”

But is it too late to affect change?

When it comes to fighting climate change, there appear to be many potential technological and natural tools in our arsenal, but how much time do we really have to use them?

“Because we’ve left it so late, we need to draw down as much carbon dioxide from the atmosphere as we can and turn it into solid carbon,” says environmental writer and activist George Monbiot in the documentary. “The best, quickest and cheapest way of doing that is to turn it into trees, to turn it into wetlands, to turn it into other ecosystems.”

“It really is not too late because social change can happen at great speed,” he says. “We can change to being an ecological civilization, and we can change very rapidly indeed.”


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Deep Impact: Heat Waves Happen at the Bottom of the Ocean Too – SciTechDaily



This visualization depicts bathymetric features of the western Atlantic Ocean Basin, including the continental shelf, captured by satellite. Credit: NOAA’s National Environmental Satellite and Information Service

First assessment of bottom marine heat waves opens a window on the deep.

The 2013-2016 marine heat wave known as “The Blob” warmed a vast expanse of surface waters across the northeastern Pacific, disrupting West Coast marine ecosystems, depressing salmon returns, and damaging commercial fisheries. It also prompted a wave of research on extreme warming of ocean surface waters.


But, as new research from the National Oceanic and Atmospheric Administration (<span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

The National Oceanic and Atmospheric Administration (NOAA) is a scientific agency of the United States government that is focused on understanding and predicting changes in Earth's oceans, atmosphere, and climate. It is headquartered in Silver Spring, Maryland and is a part of the Department of Commerce. NOAA conducts research and provides information, products, and services that are used to protect life and property, and to support economic growth and development. It also works to conserve and manage natural resources, including fisheries, wildlife, and habitats. Some of the specific activities that NOAA is involved in include weather forecasting, climate monitoring, marine biology and fisheries research, and satellite and remote sensing.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>NOAA) shows, marine heat waves also happen deep underwater.

In a paper published in the journal <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

Nature Communications
&lt;em&gt;Nature Communications&lt;/em&gt; is a peer-reviewed, open-access, multidisciplinary, scientific journal published by Nature Portfolio. It covers the natural sciences, including physics, biology, chemistry, medicine, and earth sciences. It began publishing in 2010 and has editorial offices in London, Berlin, New York City, and Shanghai.&nbsp;

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>Nature Communications on March 13, a team led by NOAA researchers used a combination of observations and computer models to generate the first broad assessment of bottom marine heat waves in the productive continental shelf waters surrounding North America.

Endangered Fish Marine Heat Waves

Marine heat waves have a significant impact on ocean ecosystems globally, disrupting the productivity and distribution of organisms, from plankton to whales. There is a significant effort to study, track, and predict the timing, intensity, duration, and physical drivers of these events. Credit: NOAA Fisheries

“Researchers have been investigating marine heat waves at the sea surface for over a decade now,” said lead author Dillon Amaya, a research scientist with NOAA’s Physical Science Laboratory. “This is the first time we’ve been able to really dive deeper and assess how these extreme events unfold along shallow seafloors.”

Marine heat waves dramatically impact the health of ocean ecosystems around the globe, disrupting the productivity and distribution of organisms as small as plankton and as large as whales. As a result, there has been a considerable effort to study, track and predict the timing, intensity, duration, and physical drivers of these events.

Most of that research has focused on temperature extremes at the ocean’s surface, for which there are many more high-quality observations taken by satellites, ships, and buoys. Sea surface temperatures can also be indicators for many physical and biochemical ocean characteristics of sensitive marine ecosystems, making analyses more straightforward.

About 90% of the excess heat from global warming has been absorbed by the ocean, which has warmed by about 1.5C over the past century. Marine heatwaves have become about 50% more frequent over the past decade.

Ling Cod Humboldt Bay Jetty in California

Ling cod, like this one caught off of Humboldt Bay Jetty in California, are a member of Pacific groundfish communities vulnerable to impacts from bottom marine heat waves. Credit: Nicholas Easterbrook/NOAA Fisheries

In recent years, scientists have increased efforts to investigate marine heat waves throughout the water column using the limited data available. But previous research didn’t target temperature extremes on the ocean bottom along continental shelves, which provide critical habitat for important commercial <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="

A species is a group of living organisms that share a set of common characteristics and are able to breed and produce fertile offspring. The concept of a species is important in biology as it is used to classify and organize the diversity of life. There are different ways to define a species, but the most widely accepted one is the biological species concept, which defines a species as a group of organisms that can interbreed and produce viable offspring in nature. This definition is widely used in evolutionary biology and ecology to identify and classify living organisms.

” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>species like lobsters, scallops, crabs, flounder, cod, and other groundfish.

Due to the relative scarcity of bottom-water temperature datasets, the scientists used a data product called “reanalysis” to conduct the assessment, which starts with available observations and employs computer models that simulate ocean currents and the influence of the atmosphere to “fill in the blanks.” Using a similar technique, NOAA scientists have been able to reconstruct global weather back to the early 19th century.

Average Intensity of Ocean Bottom Heat Waves

These illustrations show the average intensity of bottom heat waves ( heat anomalies) that occurred between 1993 and 2019 in each of the large marine ecosystems studied by a team of NOAA scientists. Credit: NOAA Physical Sciences Laboratory

While ocean reanalyses have been around for a long time, they have only recently become skillful enough and have high enough resolution to examine ocean features, including bottom temperatures, near the coast.

The research team, from NOAA, Cooperative Institute for Research in Environmental Sciences (CIRES), and National Center for Atmospheric Research (NCAR), found that on the continental shelves around North America, bottom marine heat waves tend to persist longer than their surface counterparts, and can have larger warming signals than the overlying surface waters. Bottom and surface marine heat waves can occur simultaneously in the same location, especially in shallower regions where surface and bottom waters mingle.

Lionfish Invasive Species

Lionfish have become a poster child for invasive species issues in the western north Atlantic region. Their populations continue to expand, threatening the well-being of coral reefs and other marine ecosystems. This includes the commercially and recreationally important fish that depend on them. Credit: NOAA Fisheries

But bottom marine heat waves can also occur with little or no evidence of warming at the surface, which has important implications for the management of commercially important fisheries. “That means it can be happening without managers realizing it until the impacts start to show,” said Amaya.

In 2015, a combination of harmful algal blooms and loss of kelp forest habitat off the West Coast of the United States—both caused by The Blob – led to closures of shellfisheries that cost the economy in excess of $185 million, according to a 2021 study. The commercial tri-state Dungeness crab fishery recorded a loss of $97.5 million, affecting both tribal and nontribal fisheries. Washington and Californian coastal communities lost a combined $84 million in tourist spending due to the closure of recreational razor clam and abalone fisheries.

In 2021, a groundfish survey published by NOAA Fisheries indicated that Gulf of Alaska cod had plummeted during The Blob, experiencing a 71% decline in abundance between 2015 and 2017. On the other hand, young groundfish and other marine creatures in the Northern California Current system thrived under the unprecedented ocean conditions, a 2019 paper by Oregon State University and NOAA Fisheries researchers found.

Unusually warm bottom water temperatures have also been linked to the expansion of invasive lionfish along the southeast U.S., coral bleaching and subsequent declines of reef fish, changes in survival rates of young Atlantic cod, and the disappearance of near-shore lobster populations in southern New England.

The authors say it will be important to maintain existing continental shelf monitoring systems and to develop new real-time monitoring capabilities to alert marine resource managers to bottom warming conditions.

“We know that early recognition of marine heat waves is needed for proactive management of the coastal ocean,” said co-author Michael Jacox, a research oceanographer who splits his time between NOAA’s Southwest Fisheries Science Center and the Physical Sciences Laboratory. “Now it’s clear that we need to pay closer attention to the ocean bottom, where some of the most valuable species live and can experience heat waves quite different from those on the surface.”

Reference: “Bottom marine heatwaves along the continental shelves of North America” by Dillon J. Amaya, Michael G. Jacox, Michael A. Alexander, James D. Scott, Clara Deser, Antonietta Capotondi and Adam S. Phillips, 13 March 2023, Nature Communications.
DOI: 10.1038/s41467-023-36567-0

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The SpaceX steamroller has shifted into a higher gear this year – Ars Technica



Enlarge / A Starlink mission launches on a Falcon 9 rocket Friday from Vandenberg Space Force Base.

Is it possible that SpaceX has succeeded in making orbital launches boring? Increasingly, the answer to this question appears to be yes.

On Friday the California-based company launched two Falcon 9 rockets within the span of just a little more than four hours. At 12:26 pm local time, a Falcon 9 rocket carried 52 of SpaceX’s own Starlink satellites into low-Earth orbit from a launch pad at Vandenberg Space Force Base in California. A mere 4 hours and 12 minutes later, another Falcon 9 rocket delivered two large communications satellites into geostationary transfer orbit for the Luxembourg-based satellite company SES from Kennedy Space Center.


This broke SpaceX’s own record for the shortest time duration between two launches. However, the overall record for the lowest time between two launches of the same rocket still belongs to the Russian-built Soyuz vehicle. In June 2013, Roscosmos launched a Soyuz booster from Kazakhstan, and Arianespace launched a Soyuz from French Guiana within two hours. Those launches were conducted by two separate space agencies, on separate continents, however.

Accelerating cadence

Friday’s launch of the two SES satellites was, overall, SpaceX’s 19th orbital mission for the calendar year. As of today, the company is launching a Falcon rocket every 4.1 days and remains on pace to launch approximately 90 rockets before the end of 2023.

To put this into perspective, a decade ago, the United States launched an average of 15 to 20 orbital rockets a year, total. In 2022, the United States recorded its most launches in any calendar year, ever, with 78 orbital flights. This year, barring a catastrophic accident with the Falcon 9 booster, that number will easily get into triple digits. The all-time record for orbital launches in a single year is held by the Soviet Union, with 101, in 1982.

A decade ago, SpaceX was still an upstart in the global launch industry. In the year 2013, it launched the Falcon 9 rocket a grand total of three times in a single year for the first time. This was actually a pretty monumental achievement for the company, as it introduced both its second launch pad at Vandenberg Air Force Base and a substantially upgraded variant, 1.1, of the Falcon 9 rocket. It also flew commercial missions for the first time and began experimenting with ocean-based landings.

In that competitive environment a decade ago, SpaceX still lagged far behind its main competitors, including Roscosmos, Europe-based Arianespace, and US-based United Launch Alliance. This year those numbers have swung massively around. Through today, Russia has launched three rockets, two Soyuz and one Proton, in 2023. Arianespace has yet to launch a single mission, and nor has United Launch Alliance.

No longer a competition

Put another way, SpaceX’s main competitors over the last decade have launched three rockets this year. SpaceX, by comparison, just launched three rockets in three days, including the CRS-27 mission flown for NASA on the evening of March 14. Increasingly, only the combined efforts of China’s government and its nascent commercial launch sector can pose a challenge to SpaceX’s launch dominance. That nation has a total of 11 orbital launches this year.

SpaceX founder Elon Musk has said he would like the launch industry to achieve airline-like operations with rockets one day. His company is not there yet, as it takes a couple of weeks to land, refurbish, and relaunch a Falcon 9 first stage. Each mission still requires a brand-new second stage. And the fastest turnaround time at its three launch pads, Cape Canaveral and Kennedy Space Center in Florida, and Vandenberg in California, is still about a week for each facility.

But they sure have come a long way in a decade.

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Scientists Identify Intense Heatwaves At The Bottom Of Ocean




Underwater heatwave can have significant impacts on marine life. (Representational Pic)

Global warming is causing temperature across the globe to rise. The rate has increased in the last decades, with climatologists warning of the extreme effects that the mankind has to experience. The scientists have also been tracking temperature data streaming in from ocean surfaces. But in a shocking discovery, they have found that marine heatwaves can unfold deep underwater too, even if there is no detectable warming signal above. The discovery is based on new modelling led by researchers at the US National Oceanic and Atmospheric Administration (NOAA).

The research detailing the underwater heatwave has been published in Nature Communications.


“This is the first time we’ve been able to really dive deeper and assess how these extreme events unfold along shallow seafloors,” the study’s lead author Dillon Amaya, a climate scientist with NOAA’s Physical Science Laboratory, is quoted as saying by Science Direct.

It is based on the analysis of underwater temperature of continental shelf waters surrounding North America.

“This research is particularly significant as the oceans continue to warm, not only at the surface but also at depth, impacting marine habitat along continental shelves,” said co-author Clara Deser.

The scientists found that marine heatwaves can be more intense and last longer than hot spells at the ocean surface, though it varies from coast to coast.

The simulations found that bottom marine heatwave and surface marine heatwave tend to occur at the same time in shallow regions where surface and bottom waters mingle. But in deeper parts of the oceans, bottom marine heatwaves can develop without any indication of warming at the surface.

Temperature spikes along the seafloor ranged from half a degree Celsius up to 5 degrees Celsius, the research further found.

According to NOAA, marine heatwaves are periods of persistent anomalously warm ocean temperatures, which can have significant impacts on marine life as well as coastal communities and economies.

According to data, about 90 per cent of the excess heat from global warming has been absorbed by the ocean, which has warmed by about 1.5 degrees Celsius over the past century.


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