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Fossil shells suggest carbon’s influence on the climate could grow as planet warms

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Sept. 8 (UPI) — Fresh analysis of ancient shells suggest carbon had a pronounced effect on Earth’s climate during the Eocene Epoch, some 35 million years ago.

The findings, published this week in the journal Nature Communications, suggest that as the planet continues to warm, the climate will become more sensitive to changes in carbon levels.

At the outset of the Eocene Epoch, which lasted from 56 to 34 million years ago, temperatures were 14 degrees Celsius greater than they are today. Rainforests extended throughout Antarctica, and croc-filled swamps stretched across Europe and North America.

Throughout the second half of the Eocene Epoch, Earth’s climate rapidly cooled and glaciation spread across the planet’s poles. Until now, the relationship between carbon levels and climate change during the Eocene wasn’t well understood.

To trace the rise and fall of atmospheric carbon levels during the Eocene, researchers measured ratios of boron isotopes inside the fossilize shells of ancient marine plankton deposited in marine sediment layers.

Scientists used the measurements to estimate water acidity and calcite saturation during the Eocene, with the estimates allowing them to model changes in the atmospheric carbon concentrations during the Eocene.

The analysis revealed a strong link between carbon concentrations and global warming, showing Earth hosted large concentrations of carbon in its atmosphere and oceans at the beginning of the Eocene Epoch.

However, the fossil shells show a combination of volcanism, weathering of rocks and burial of organic material helped drastically reduce carbon levels, leading to a prolonged cooling effect.

“These methods really allow us to get a unique insight into not only how the climate system varied in the past, but why,” study co-author Gavin Foster, professor of isotope geochemistry in ocean and earth science at the University of Southampton, said in a news release.

“It’s this ability to accurately reconstruct atmospheric CO2 in the past that means we can determine climate sensitivity millions of years ago, providing a powerful test of the understanding that is encapsulated in the state-of-the-art climate models that are key to predicting our future warmth,” Foster said.

The findings could have implications for the models climate scientists rely on to predict the influence of carbon on sea level rise and global warming, as well as shifts in precipitation patterns and other climatic effects.

“Now that we have demonstrated that the climate is more sensitive when it is warm, like it was during the Eocene, the next step is to work out why this is and make sure this behavior is well represented in the climate models that are used to predict our future climate,” said study co-author Tali Babila, post-doctoral researcher at Southampton.



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U.S. space mining policies may trigger regulatory ‘race to the bottom,’ scientists warn

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Oct. 8 (UPI) — In a newly published policy paper, a pair of Canadian scientists warn that the United States is angling to establish itself as the de facto gatekeeper of the moon and other celestial bodies.

Earlier this year, NASA published a new set of rules for lunar mining and other space activities, dubbing the voluntary guidelines the “Artemis Accords.”

Aaron Boley and Michael Byers, authors of the new Science paper, argue that the Artemis Accords are part of a concerted effort by the U.S. and NASA to set a legal precedent for space-based resource extraction.

“It’s not the Artemis Accords alone that are problematic,” Michael Byers, professor of global politics and international law at the University of British Columbia, told UPI in an email. “Rather, it’s the ongoing and concerted U.S. diplomatic effort to promote national regulation of space mining and to proceed with resource extraction before a multilateral agreement has been negotiated.”

In 2015, Congress passed the Commercial Space Launch Competitiveness Act, which allowed U.S. citizens and companies to “engage in the commercial exploration and exploitation of space resources.”

Last month, NASA said it plans to buy lunar soil from a commercial company.

“We are buying the regolith, but we’re doing it really to demonstrate that it can be done, that the resources extracted from the moon are in fact owned by the people who invest their sweat, and their treasure, and their equity into that effort,” NASA Administrator Jim Bridenstine said during a virtual presentation in September.

Byers and his co-author Boley, professor of astronomy and physics at the University of British Columbia, see the succession of legislative and policy moves by the United States as an attempt to establish national regulation of space mining.

“The current U.S. approach to space mining emphasizes national regulation and rejects space as being a ‘global commons,'” Byers told UPI. “The result could be inconsistent national laws, a regulatory ‘race to the bottom’ and even ‘flags of convenience’ as nations compete to attract space mining companies.”

Without international standards and an independent system of monitoring, Byers and Boley argue, bad behavior by one nation begets bad behavior by another. The paper’s authors suggest bilateral agreements like the Artemis Accords could imperil efforts to forge future international space agreements.

“A better alternative would be to negotiate a multilateral agreement, and to do so now, rather than seeking to set precedents through unilateral and bilateral actions,” Byers said.

Byers and Boley would like to see a multilateral approach to space resource management. The authors point to the Montreal Protocol on Substances that Deplete the Ozone Layer as a model for international cooperation.

“The key is to have solid science, open information sharing, alternative technologies, and cooperation among actors,” Byers said. “An international framework will set the standards and provide the required transparency. It will also give a voice to nations that cannot operate in space now, but will in the future. Scientists, engineers, and industry can do the rest.”

While the Montreal Protocol has enjoyed considerable success in shrinking the hole in the ozone layer, the fight to curb the release of ozone-depleting chemicals isn’t a precise corollary for regulating space mining.

“Many in the U.S. space industry would disagree with the idea that we need an international, multi-lateral treaty to move forward with space mining,” Alex Gilbert, research fellow at the Payne Institute at the Colorado School of Mines, told UPI in an email. “There is no evidence that a multilateral or global treaty would be more effective than the approach the United States is taking.”

Rather than the Montreal Protocol, Gilbert points to the UN Convention on the Law of the Sea — not as an ideal model but as an example of a multinational agreement gone wrong. The United States declined to sign the law because it requires participation in an international profit sharing mechanism.

“The administration of UNCLOS deep sea mining regime leaves much to be desired — commercial extraction has yet to take place, the profit sharing mechanism is not clearly established, and it is unclear whether there will be sufficient levels of environmental protection,” Gilbert said. “Most deep seabed mining leases have gone to China and without effective governance it is not clear that that system is more effective than alternatives.”

To date, attempts to establish a multinational space mining regulatory regime have faltered, and Gilbert suggests bilateral agreements like the Artemis Accords can serve as a stepping stone to a multinational space governance regime.

“The U.S. is uniquely suited to be a leader on space mining policy and space policy more broadly,” Gilbert said. “It is currently engaged with space partners around the globe and its efforts are making it a global leader in space policy. International accords are difficult to negotiate but the U.S. approach is well suited to developing an iterative, collaborative and international process.”



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Ocean patterns help scientists forecast drought, water flow in the Colorado river

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Oct. 9 (UPI) — By analyzing what researchers call “long-term ocean memory,” scientists have been able to identify connections between flow rates in the Colorado River and sea surface temperatures in parts of the Pacific and Atlantic oceans.

The breakthrough analysis — described Friday in the journal Communications Earth and Environment — allowed scientists to develop a forecasting model capable of predicting the Colorado River water supply on multi-year timescales.

The Colorado River, the most important water resource in the West, is essential to energy production, food and drinking water security, forestry and tourism in California, Arizona, New Mexico, Colorado and Utah.

Access to more accurate long-term forecasting models could aid water resource management decisions.

“Using our tool we can develop an operational forecast of the Colorado River’s water supply,” lead study author Yoshimitsu Chikamoto, assistant professor of earth systems modeling at Utah State University, said in a news release.

Current forecasting models for predicting droughts and Colorado River flow are over-reliant on short-term weather patterns. The models are easily skewed by short-term weather phenomena — a big storm or an especially dry couple of months, for example.

“This new approach is robust and means that water managers, for the first time, have a tool to better estimate water supply in the Colorado River for the future,” said study co-author Robert Gillies, director of the Utah Climate Center and professor at Utah State University. “The model can be run iteratively so every year a new forecast for the next three years can be created.”

A two to three year lead on water flow and drought forecasts can allow farmers to make important decisions on crop rotations.

To build their model, scientists used their ocean memory analysis to draw connections between sea surface temperature and subsequent atmospheric effects. Next, researchers accounted for the influence of land systems on precipitation patterns — including soils, groundwater, vegetation and snowpack.

Because the upper basin of the Colorado River isn’t located in the Southwest, forecasters have previously failed to account for the influence of climate pattern El Niño and La Niña on Colorado River flow.

The new predictive model accounts for a complex array of natural phenomena: currents, water mixing and heat exchange in the ocean; clouds and aerosols in the atmosphere; and surface characteristics across the West’s semi-arid landscape.

In addition to aiding the decision making of farmers and water resource managers, the new model could used to inform preparations for future wild fire seasons.



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Scientists warn of human-to-wildlife COVID-19 transmission risk

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Oct. 9 (UPI) — The risk of human-to-wildlife COVID-19 transmission is real and significant, scientists warn in a paper published this week in the journal Mammal Review.

Although the exact origins of the COVID-19 pandemic aren’t clear, most researchers estimate the virus made the jump from bats to pangolins before infecting humans. Now, scientists worry the virus could make the jump from humans back into wild animal populations.

If COVID-19 managed to infect and spread among wild animals, it could pose a threat to endangered species. As well, wild animal populations could serve as a reservoir for further virus evolution and a source of future human outbreaks.

So far, scientists have documented human-to-animal coronavirus spread on a mink farm and at the zoo, where several tigers and lions were infected.

At home, humans have transmitted the virus to domestic cats and dogs. Some semi-feral cats in Wuhan and the Netherlands have also tested positive for antibodies triggered by a coronavirus infection.

“There have not been any reports yet of actual wildlife being infected with [the coronavirus],” lead study author Sophie Gryseels told UPI in an email.

“We hope this is because it has actually not happened yet, but then again, there is not much surveillance going on of healthy wildlife for [coronavirus] infections, so if it had happened already, we might not know about it,” said Gryseels, a biologist at the University of Antwerp in Belgium.

As well, infected animals have exhibited only mild symptoms, but Gryseels said it’s possible the disease takes a more serious course among other animal species.

Though COVID-19 has yet to have grave consequences for animal populations, Gryseels suggests the threat of human-to-animal transmission is real and significant.

“We know of several mammal species that are about as susceptible to [the coronavirus] as humans are, like ferrets, mink, hamsters, North American deer mice, tigers and macaques and a few other species,” she said. “When they are experimentally inoculated with [the coronavirus], or in some cases accidentally infected by human caretakers, the infection takes off easily, and they can further transmit the virus to co-housed animals.”

Gryseels and her colleagues hope their paper will inspire caretakers, scientists and others who interact with wild and captive animals to take extra precautions.

Researchers suggest the same safety precautions that can help slow human transmission — hand washing, mask wearing and social distancing — can help prevent human-to-animal transmission.

For most people, the risk of human-to-animal COVID-19 transmission is minimal.

“Luckily for us the mammal species that humans probably have the most interactions with in total in global terms, and would thus seem to be most likely to catch the virus if they were biologically susceptible, are house mice and brown and black rats — who luckily don’t seem to be susceptible,” Gryseels said.

While researchers expect humans to eventually develop herd immunity against COVID-19, via a combination of infection-triggered immunity and vaccination, other animal species might not be so lucky.

The combination of susceptibility and short lifespan could leave some species especially vulnerable to COVID-19, including the North American deer mouse, the bank vole in Europe, macaques in Asia and stray cat populations all over the world.

“The main worry then is that, like in human populations, the virus could just continue to spread without stop,” Gryseels said. “Especially in populations where animals have a short life span and high reproductive rate, such as in rodents, we worry that the virus can persist for a long time, as there are continuously new, susceptible animals being born that are naive for the virus.”



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