Antarctica’s Ocean Flip: Satellites Reveal Sudden Salt Surge Melting Ice from Below

In a shocking discovery, researchers have found that the Southern Ocean surrounding Antarctica has undergone a dramatic and unexpected shift. Since 2015, the region has lost an astonishing amount of sea ice, equivalent in size to Greenland – the largest environmental change witnessed anywhere on Earth in recent decades.

The ocean’s surface salinity has been rising, while the sea ice is rapidly declining. This sudden turn of events has significant implications for the planet. The findings were published in a study led by the University of Southampton, using European satellite data to reveal the unexpected changes in the Southern Ocean.

For decades, the ocean’s surface had freshened (becoming less salty), helping sea ice grow and thrive. However, this trend has sharply reversed, with scientists detecting a sudden rise in surface salinity south of 50° latitude. This shift has coincided with the dramatic loss of sea ice around Antarctica and the re-emergence of the Maud Rise polynya – a massive hole in the sea ice nearly four times the size of Wales.

The findings were published on June 30 in the Proceedings of the National Academy of Sciences. Dr. Alessandro Silvano, who led the research, warned that this new state could have permanent consequences for the Southern Ocean and the planet as a whole. The effects are already global: stronger storms, warmer oceans, and shrinking habitats for penguins and other iconic Antarctic wildlife.

The research team has attributed the sudden rise in surface salinity to a weakening of stratification between water layers. In the winter, cold, fresh surface water overlays warmer, saltier waters from the deep. As the surface cools and sea ice forms, the density difference weakens, allowing heat to be transported upward, melting the sea ice from below.

The early 1980s saw a strengthening of stratification, trapping heat below and sustaining more sea ice coverage. However, this trend has reversed, with new satellite technology and data from floating robotic devices revealing that surface salinity is increasing, stratification is weakening, and sea ice has reached multiple record lows – with large openings of open ocean in the sea ice (polynyas) returning.

This groundbreaking study highlights the urgent need for continuous satellite and in-situ monitoring to better understand the drivers of recent and future shifts in the ice-ocean system. The project was supported by the European Space Agency, and the paper “Rising surface salinity and declining sea ice: a new Southern Ocean state revealed by satellites” is available online.

The dangers of fire smoke exposure are well-documented, but until now, the full extent of its impact on our bodies has been unclear. A recent study led by researchers at Harvard T.H. Chan School of Public Health reveals that fire smoke can alter our immune system on a cellular level, leaving lasting changes and increasing our risk of serious health problems.

The study examined blood samples from 31 individuals who had been exposed to fire smoke and compared them to those from 29 non-exposed individuals. The results showed significant changes in the immune cells of those who had been exposed to smoke. These changes included an increase in memory CD8+ T cells, which are crucial for long-term immunity against pathogens, as well as elevated activation and chemokine receptor biomarkers that indicate inflammation and immune activity.

The researchers also found changes in 133 genes related to allergies and asthma in the individuals who had been exposed to smoke. Moreover, their immune cells were more likely to be bound with toxic metals like mercury and cadmium, which can further harm our health.

“This study fills a critical knowledge gap by showing exactly how fire smoke exposure can damage the body,” said Kari Nadeau, corresponding author of the study and chair of the Department of Environmental Health. “Our findings have significant implications for public health leaders and clinicians who need to respond to the growing threat of wildfires.”
The study’s lead author, Mary Johnson, added that the immune system is extremely sensitive to environmental exposures like fire smoke, even in healthy individuals. Knowing exactly how smoke exposure can harm our bodies may help us detect immune dysfunction earlier and pave the way for new therapeutics to mitigate or prevent the health effects of smoke exposure.

The researchers also noted that their study could inform environmental and public health policies and investments, such as increasing public awareness about the dangers of smoke exposure and the importance of following evacuation procedures during wildfires.
The study was funded by several organizations, including the National Institute of Environmental Health Sciences, the National Heart, Lung, and Blood Institute, and the San Francisco Cancer Prevention Foundation.

In conclusion, this study highlights the need for increased caution when it comes to fire smoke exposure. By understanding the full extent of its impact on our bodies, we can take steps to protect ourselves and others from its toxic effects.

The study published in Science Advances by NASA scientists has revealed a significant correlation between the strength of the Earth’s magnetic field and fluctuations in atmospheric oxygen levels over the past 540 million years. This groundbreaking research suggests that processes deep within the Earth’s core might be influencing habitability on the planet’s surface.

At the heart of this phenomenon lies the Earth’s magnetic field, which is generated by the flow of molten material in the planet’s interior. Like a giant electromagnet, this process creates a dynamic field that has been fluctuating over time. The authors of the study point out that the role of magnetic fields in preserving the atmosphere is still an area of active research.

To uncover the hidden link between the Earth’s core and life-sustaining oxygen, scientists have analyzed magnetized minerals that record the history of the magnetic field. These minerals, formed when hot materials rise with magma at gaps between tectonic plates, retain a record of the surrounding magnetic field as long as they are not reheated too severely. By studying these ancient rocks and minerals, researchers can deduce historic oxygen levels based on their chemical contents.

The databases compiled by geophysicists and geochemists have provided valuable information on both the Earth’s magnetic field and oxygen levels over comparable ranges. Until now, no scientists had made a detailed comparison of the records. The findings of this study suggest that the two datasets are remarkably similar, with the planetary magnetic field following similar rising and falling patterns as oxygen in the atmosphere for nearly half a billion years.

The implications of this discovery are profound, suggesting that complex life on Earth might be connected to the interior processes of the planet. Coauthor Weijia Kuang said, “Earth is the only known planet that supports complex life. The correlations we’ve found could help us understand how life evolves and how it’s connected to the interior processes of the planet.”

Further research aims to examine longer datasets to see if the correlation extends farther back in time. The study also plans to investigate the historic abundance of other chemicals essential for life, such as nitrogen. As for the specific causes linking the Earth’s deep interior to life on the surface, scientist Kopparapu said, “There’s more work to be done to figure that out.”