June 15, 2023

Thanks for reading Axios Science. This edition is 1,528 words, about a 6-minute read.

1 big thing: A crucial year for learning ocean warming's effects

Illustration: Natalie Peeples/Axios

This year is crucial for understanding the trajectory of the planet's marine life, experts say, as a combination of threatening factors line up to test species' tolerance of warmer waters.

Why it matters: The effects of extreme heat on humans and other land-dwelling animals are well-documented. Less is known about their impact on the ocean's plants and animals, which underpin economies and help the ocean to regulate the planet's climate.

What's happening: Global sea surface temperatures jumped to unprecedented levels over the past several months.

  • The Pacific Ocean is transitioning out of La Niña conditions that have been in place for more than two years. As El Niño sets in, less colder water is being carried up from the depths of the ocean and mixed at the surface, leading the temperature of the sea surface water to rise.
  • But the sea surface temperature rises observed this year can't be ascribed to an El Niño event that is just emerging, says Kim Cobb, an earth sciences professor at Brown University. "It takes a full year to see the full impact."
  • Other explanations — including less dust from the Sahara Desert moving across the Atlantic Ocean that typically checks ocean temperatures there — are being put forth.

On top of that, marine heatwaves — once-rare ocean weather events where water temperatures rise and persist for days or months — are becoming more common. The number of marine heatwave days doubled between 1982 and 2016, and is projected to increase even more.

  • They're also occurring on the seafloor around North America.
  • The lack of long-term observational records of marine heatwaves limits scientists' knowledge about their frequency, says Curtis Deutsch, a geoscience professor at Princeton University.

2. Part II: The impact

Warming ocean waters from climate change are driving a drop in water pH and a decrease in oxygen in the water, or hypoxia. Ocean warming also amps up the metabolism of marine animals that then need more food. At the same time, a dearth of oxygen can reduce that food supply.

  • Modeling and direct observations indicate marine heatwaves are commonly associated with low oxygen extremes as well, Deutsch says.
  • Populations of marine species will move or go locally extinct if hit with heatwaves, Deutsch says. The big question is, "How frequent can these extreme events happen and we still have a viable population?"
  • Most of the 32 coral reefs analyzed in a recent study already have at least weak hypoxic conditions — and it is expected to worsen as the oceans warm.

Zoom in: A brittle star species was absent from a coral reef on the Caribbean coast of Panama with an average temperature the species can tolerate, according to a study Deutsch and his colleagues published this year.

  • Deutsch says that absence can be explained by the frequency of ocean weather extremes occurring just a couple of weeks a year.

The big picture: The impact of warming ocean water and hypoxia on different species is being documented around the world — from sea urchins that have a harder time flipping over in oxygen-depleted water to long-term warming diminishing the nutritional value of kelp to fish migrating to cooler waters.

  • In India's Gulf of Mannar, annual blooms of algae cause significant coral mortality through asphyxiation, says K. Diraviya Raj, a professor at Suganthi Devadason Marine Research Institute in India, who studies corals in the gulf. The consistent timing of the blooms each year indicates the role of climate change, he says.
  • One recent study of reef fish fossils from 50 million to 60 million years ago suggests the fish developed faster rates of growth in the warm oceans of that time. Scientists are concerned warming from climate change could push some species to live fast and die young.

But, but, but... There are some species thriving. On some isolated reefs, there are corals more resistant to changes in heat than others.

  • Still, "it just means they are more resistant not that they are free from the impacts," says Thomás Banha, a Ph.D. student studying coral reef ecology and conservation at the University of São Paulo.
  • Coral bleaching can happen due to climate change but can also occur seasonally. Marine "heat waves are becoming more common and hindering the capacity of corals to recover from natural bleaching," Banha says.

What to watch: "This is an important year for monitoring and identifying ways to assist species through these next couple of decades," Cobb says.

  • The combination of El Niño and global warming risks "a stepwise decline in marine ecosystem capacity," she says, recalling the mass coral mortality events she witnessed in 2016, also an El Niño year. "It's not steady and gradual, it's a cliff that species and ecosystems fall off."
  • "It is very alarming that there are such large portions of the ocean that are so warm ahead of an El Niño event," she says. "It does not bode well for ecosystems around the world."

3. FDA advisers endorse new target for COVID booster

Illustration: Sarah Grillo/Axios

An expert panel for the Food and Drug Administration today unanimously recommended that drug manufacturers target omicron subvariant XBB, which is currently responsible for nearly every infection in the U.S., in the next round of COVID boosters, Axios' Sabrina Moreno reports.

Why it matters: The bivalent booster currently available targets variants no longer circulating and is showing signs of waning protection against severe disease, per data presented during the daylong meeting.

  • Advisers agreed the new boosters should specifically protect against the XBB.1.5 variant, which accounted for nearly 40% of COVID cases as of last week.
  • Vaccine manufacturers Pfizer, Moderna and Novavax have already begun to develop a shot targeting this strain and indicated that it would be ready for distribution, pending regulatory approval, by early fall.

What’s next: The FDA still has to decide whether to follow the committee’s recommendations, but they align with the agency's own suggestions outlined earlier this week.

Yes, but: “This is not going to be the final formulation for this vaccine forevermore,” said Peter Marks, head of the FDA's vaccine division. “It will likely require another update at some point."

4. Groundwater removal tilted Earth 31.5 inches

A cornfield is irrigated in Germany's Peine district last year. Photo: Julian Stratenschulte/picture alliance via Getty Images

The spin of the planet tilted 31.5 inches to the east between 1993 and 2010 due to humans pumping groundwater, according to a new study.

The big picture: Earth’s rotational axis drifts naturally but its direction shifted east in the 1990s. Previous research attributed that drift to large amounts of water being moved by glacial melt, groundwater removal and other activities that contribute to rises in sea level.

  • When a large mass of water is moved, the planet's center of gravity also moves.

What's new: Researchers at Seoul National University determined "the redistribution of groundwater actually has the largest impact on the drift of the rotational pole," geophysicist Ki-Weon Seo said in a press release.

  • The researchers modeled how the drift in Earth's rotational axis changed and how water moved from the melting of ice sheets and glaciers as well as the redistribution of groundwater.
  • They found the distribution of groundwater had to be included in the model for it to match observations of the shift.
  • "Earth's pole has drifted toward 64.16°E at a speed of 4.36 cm/yr during 1993–2010 due to groundwater depletion and resulting sea level rise," the authors report.

The impact: Changes in the rotational pole due to groundwater pumping aren't expected to shift the planet's seasons, Surendra Adhikari, a research scientist at the Jet Propulsion Laboratory who was not involved in the study, said in the release.

  • It normally drifts several meters in a year and the groundwater contribution is on the order of centimeters.
  • Over time, though, the drift could affect the planet's climate.

5. Worthy of your time

IBM gets usable results out of quantum processor (John Timmer — ArsTechnica)

A researcher who publishes a study every two days reveals the darker side of science (Manuel Ansede — El País)

China's quantum leap — Made in Germany (Sandra Petersmann and Esther Felden — DW)

The coolest library on Earth (Elizabeth Landau — Hakai)

6. Something wondrous

Saturn’s E ring is fed with icy particles from Enceladus’ plume. Credit: NASA/JPL-Caltech/Space Science Institute

Icy grains spewed into space from Saturn's moon Enceladus contain phosphorus — a prerequisite for life as we know it, scientists reported this week.

Why it matters: The discovery is the latest indicator that this icy moon has the ingredients to be potentially habitable for life.

  • "Phosphorus, the least abundant of the bio-essential elements, has not yet been detected in an ocean beyond Earth," the researchers write this week in the journal Nature.
  • Phosphate, an ion of phosphorus, forms the backbone of DNA and helps organisms make the energy-carrying molecule adenosine triphosphate (ATP).

Details: Enceladus has an ocean beneath its ice-covered surface that ejects water from geysers that then supply icy bits to an outer ring of Saturn.

  • Earlier analysis of those salt-rich ice grains by the Cassini spacecraft indicated Enceladus' ocean contained sodium, potassium, chlorine and other organic compounds.
  • In the new study, researchers used data collected from Cassini's Cosmic Dust Analyzer. They found sodium phosphate molecules in 9 of 345 ice grains Cassini analyzed as it passed through Saturn's outer E ring.
  • In laboratory studies, the team then demonstrated phosphate could exist on Enceladus in much higher concentrations — several hundredfold — than on Earth and possibly in the icy oceans of other planets where alkaline water can interact with rocks.

Big thanks to Laurin-Whitney Gottbrath and Andrew Freedman for helping to edit this week's edition, to Natalie Peeples on the Axios Visuals team and to copy editor Carolyn DiPaolo.