Island-wide field surveys illuminate land-sea connections in Mo‘orea

Mo'orea, French Polynesia, is surrounded by a diverse and vibrant coral reef ecosystem.
Photo Credit: Christian John

A massive, multi-year scientific expedition led by researchers from the University of California, Santa Barbara and collaborating institutions, including the University of Hawai‘i (UH) at Mānoa, determined that land use on tropical islands can shape water quality in lagoons and that rainfall can be an important mediator for connections between land and lagoon waters. These findings provide vital information for ecosystem stewards facing global reef decline. Their findings were published recently in Limnology and Oceanography.

“This study is pretty groundbreaking in terms of its scale,” said Christian John, lead author of the study and postdoctoral scholar at the University of California, Santa Barbara. “We looked at algal tissue nutrients, water chemistry, and microbial communities at almost 200 sites around the island of Mo‘orea, French Polynesia, and we repeated this sampling over multiple years.”

“The links between land and sea are dynamic and complex, so it’s a topic that has remained elusive to science,” said Mary Donovan, co-author and faculty at the Hawai‘i Institute of Marine Biology in the UH Mānoa School of Ocean and Earth Science and Technology. “It took a dream team to pierce through that complexity. We brought together a group of interdisciplinary thinkers, from students to senior investigators, across at least five major institutions to tackle this immense challenge.”

A new study reveals how oxygen first reached Earth’s oceans

WHOI Geochemist Andy Heard uses precise measurements of isotope ratios in sedimentary rocks to learn about the history of oxygen in Earth’s ocean.
Photo Credit: Daniel Hentz, ©Woods Hole Oceanographic Institution

For roughly two billion years of Earth’s early history, the atmosphere contained no oxygen, the essential ingredient required for complex life. Oxygen began building up during the period known as the Great Oxidation Event (GOE), but when and how it first entered the oceans has remained uncertain.

A new study published in Nature Communications shows that oxygen was absorbed from the atmosphere into the shallow oceans within just a few million years—a geological blink of an eye. Led by researchers at Woods Hole Oceanographic Institution (WHOI), the work provides new insight into one of the most important environmental shifts in Earth’s history.

“At that point in Earth’s history, nearly all life was in the oceans. For complex life to develop, organisms first had to learn not only to use oxygen, but simply to tolerate it,” said Andy Heard, lead author of the study and assistant scientist at WHOI. “Understanding when oxygen first accumulated in Earth’s atmosphere and oceans is essential to tracing the evolution of life. And because ocean oxygenation appears to have followed atmospheric oxygen surprisingly quickly, it suggests that if we detect oxygen in the atmosphere of a distant exoplanet, there’s a strong chance its oceans also contain oxygen.”

What Is: An Ecosystem

The Holocoenotic Nature of the Biosphere
Image Credit: Scientific Frontline / stock image

The Genesis of a Paradigm 

The concept of the ecosystem represents one of the most significant intellectual leaps in the history of biological science. It is not merely a label for a collection of living things, but a sophisticated framework that integrates the chaotic multiplicity of the natural world into a coherent, functional unit. To understand the ecosystem is to understand the fundamental architecture of life on Earth. This report provides an exhaustive analysis of the ecosystem concept, tracing its historical lineage, dissecting its thermodynamic and biogeochemical engines, exploring its diverse manifestations across the globe, and evaluating its resilience in the face of unprecedented anthropogenic pressure. 

Over half of global coastal settlements are retreating inland due to intensifying climate risks

Hurricane Florence moved toward the U.S. East Coast as it intensified to a Category 4 storm, with one-minute sustained winds of 130 mph Monday September 10, 2018. This image, captured by the GOES East satellite at 10:00 am ET, showed Florence in the western Atlantic, about 600 miles southeast of Bermuda, at Category 3 intensity. The storm had developed a small but well-defined eye and a symmetrical appearance typical of major hurricanes that are rapidly intensifying.
Image Credit: NOAA

For centuries, coastlines have attracted dense human settlement and economic activity. Today, more than 40 percent of the global population lives within 100 kilometers of the coast, facing accelerating sea-level rise, coastal erosion, flooding, and tropical cyclones. 

Although moving away from the coast - known as “retreat” - is often viewed as an adaptive strategy, its global extent and drivers have remained unclear. A new study published in Nature Climate Change fills this gap by providing the first global evidence that coastal retreat is driven more by social and infrastructural vulnerability than by historical exposure to hazards. 

The study was conducted by an international team led by researchers from Sichuan University and included remote sensing experts from the University of Copenhagen (Alexander Prishchepov and Shengping Ding, IGN). It maps settlement movements across 1,071 coastal regions in 155 countries. By integrating nighttime light observations with global socioeconomic datasets, the researchers found that 56% of coastal regions have retreated from the coast from 1992 to 2019, and 16% of regions, including the Copenhagen area in Denmark, have moved closer to the coast, while 28% have remained stable. 

The seamounts of Cape Verde: a biodiversity hotspot and a priority for marine conservation in the central-eastern Atlantic

Image Credit: Projecte Luso/iMirabilis2/iAtlantic

An international team led by Covadonga Orejas, a researcher at the Gijón Oceanographic Centre of the Spanish Institute of Oceanography (IEO-CSIC); Veerle Huvenne, a researcher at the UK National Oceanography Centre (NOC); and Jacob González-Solís, professor at the Faculty of Biology and the Biodiversity Research Institute (IRBio) of the University of Barcelona, has published the first comprehensive study on the seamounts of the Cape Verde archipelago, their biodiversity, ecological functionality and socio-economic relevance in the journal Progress in Oceanography.

These volcanic formations — at least 14 large mountains and numerous smaller elevations — act as veritable oases of life in the deep ocean, concentrating nutrients and modifying the circulation of underwater currents. This supports exceptional biodiversity, ranging from microorganisms to communities of deep-sea corals and sponges, as well as sharks, turtles, seabirds and cetaceans. Their position between the temperate waters of the North Atlantic and the tropical waters of the South, further enhances their productivity and ecological connectivity. 

Antarctic mountains could boost ocean carbon absorption

Glaciers transport sediments from Antarctica to the coast.
Photo Credit: Dr Kate Winter, Northumbria University

Research involving scientists from Newcastle University has revealed new hope in natural environmental systems found in Antarctica which could help mitigate the overall rise of carbon dioxide. 

As Antarctica's ice sheets thin due to climate change, newly exposed mountain peaks could significantly increase the supply of vital nutrients to the Southern Ocean which surrounds the continent, potentially enhancing its ability to absorb atmospheric carbon dioxide over long timescales, according to the research published in Nature Communications. 

Led by Northumbria University, a team of scientists looked at analysis of sediment samples from East Antarctica's Sør Rondane Mountains. They discovered that weathered rocks exposed above the ice surface contain iron concentrations up to ten times higher than previously reported from the Antarctic continent. This bioavailable iron is transported to the ocean by glaciers and icebergs, where it fuels the growth of phytoplankton – microscopic marine organisms that absorb CO₂ through photosynthesis. 

Rocks on Faults Can Heal Following Seismic Movement

At the Cascadia subduction zone in the Pacific Northwest, one tectonic plate is moving underneath another. New experimental work at UC Davis shows how rocks on faults deep in the Earth can cement themselves back together after a seismic movement, adding to our knowledge of how these faults behave.
Photo Credit: of Otter Rock, Oregon by USGS

Earthquake faults deep in the Earth can glue themselves back together following a seismic event, according to a new study led by researchers at the University of California, Davis. The work, published in Science Advances and supported by grants from the National Science Foundation, adds a new factor to our understanding of the behavior of faults that can give rise to major earthquakes. 

“We discovered that deep faults can heal themselves within hours,” said Amanda Thomas, professor of earth and planetary sciences at UC Davis and corresponding author on the paper. “This prompts us to reevaluate fault rheological behavior, and if we have been neglecting something very important.” 

Researchers link Antarctic ice loss to ‘storms' at the ocean's subsurface

Mattia Poinelli, a UC Irvine postdoctoral scholar in Earth system science and NASA JPL research affiliate, outlines in a newly published study the impact of submesoscale events – small, subsurface ocean eddies and vortices – on Antarctica’s ice sheets. “Despite being largely overlooked in the context of ice-ocean interactions,” he says, “[they] are among the primary drivers of ice loss.”
Photo Credit: Steve Zylius / UC Irvine

Researchers at the University of California, Irvine and NASA’s Jet Propulsion Laboratory have identified stormlike circulation patterns beneath Antarctic ice shelves that are causing aggressive melting, with major implications for global sea level rise projections.

In a paper published recently in Nature Geoscience, the scientists say their study is the first to examine ocean-induced ice shelf melting events from a weather timescale of just days versus seasonal or annual timeframes. This enabled them to match “ocean storm” activity with intense ice melt at Thwaites Glacier and Pine Island Glacier in the climate change-threatened Amundsen Sea Embayment in West Antarctica.

The research team relied on climate simulation modeling and moored observation tools to gain 200-meter-resolution pictures of submesoscale ocean features between 1 and 10 kilometers across, tiny in the context of the vast ocean and huge slabs of floating ice in Antarctica.

Destination: Mars. First Stop: Iceland?

This picturesque vista is the watershed in southwest Iceland, where researchers collected mars rock analog samples.
Image Credit: Michael Thorpe/NASA Goddard

To say that a trip from Earth to Mars is merely a long one would be a massive understatement. On July 30, 2020, when the National Aeronautics and Space Administration (NASA) sent its Mars rover “Perseverance” atop an Atlas V rocket to the red planet to collect rock samples, it took the rover nearly seven months to reach its destination. This was only one step in a complex process that will take at least a decade to bring home these samples from Mars. While this is an unusually long wait for a sample shipment, it gives scientists ample time to find the best approach to study these rare and precious rocks.

In preparation, an international collaboration of scientists has started investigating sedimentary rock samples found in Iceland, a country whose terrain shares some compositional similarities and whose climate may be similar to ancient climates in certain Martian regions. Their results, published today in American Mineralogist, shed light on how high-resolution analyses of these complex, natural minerals can give scientists a deeper understanding of their geological history, both at home on Earth and 194 million miles away on Mars, though this requires careful interpretation. This collaboration is made up of researchers from the University of Maryland, NASA Goddard, Johnson Space Center, University of Göttingen, Chungbuk National University, and the National Synchrotron Light Source II (NSLS-II), a U.S. Department of Energy (DOE) Office of Science user facility at DOE’s Brookhaven National Laboratory.

Earth Science: In-Depth Description

Image Credit: Scientific Frontline / stock image

Earth Science is the comprehensive study of the planet Earth, encompassing its physical composition, structure, the processes that shape it, and its history. Its primary goal is to understand the complex, integrated systems of our planet—including its solid land (lithosphere), water (hydrosphere), air (atmosphere), and life (biosphere)—and how they interact, change over time, and affect human life.

UC Irvine team track massive ice loss from Berry Glacier in West Antarctica

UC Irvine researchers analyzed decades worth of satellite data to better understand the causes of the rapid retreat of Berry Glacier, a tributary of the Getz Ice Shelf (pictured) in West Antarctica.
Photo Credit: NASA

Berry Glacier, a tributary of the Getz Ice Shelf in West Antarctica, has deteriorated dramatically in the past three decades, according to researchers in the Department of Earth System Science at the University of California, Irvine. In a study published recently in Nature Communications, the scientists documented that in the period spanning 1996 to 2023, the glacier retreated seven-tenths of a kilometer per year for a total of 18 kilometers, about 11 miles. 

Berry Glacier thinned by 11 meters per year during the study period, and its retreat velocity increased by 64 percent, resulting in a loss of 130 gigatons of ice mass. The team derived these results by analyzing synthetic-aperture radar interferometry data from several missions, including ERS-1/2, ALOS-1/2 PALSAR, Sentinel-1, COSMO-SkyMed and the RADARSAT Constellation Mission. 

New study reveals fastest Antarctic glacier retreat in modern history

Hektoria and Green, once glaciated, are now reduced to drifting ice rubble.
Photo Credit: Naomi Ochwat, lead author of the study and Post-Doctoral Associate at CU Boulder’s Cooperative Institute for Research in Environmental Sciences (CIRES), 26 February 2024.

A glacier on the Eastern Antarctic Peninsula has experienced the fastest recorded ice loss in modern history, according to a landmark study co-authored by Swansea University.

Published in Nature Geoscience, the research reveals that Hektoria Glacier lost nearly half its length—eight kilometers of ice—in just two months during 2023; a pace similar to the dramatic retreats seen at the end of the last ice age.

Led by the University of Colorado Boulder, an international team—including Swansea glaciologist, Professor Adrian Luckman—found that Hektoria’s retreat was boosted by the shape of the land beneath it.

Hektoria Glacier rested on an ice plain—a flat stretch of bedrock below sea level—which, once retreat began, saw large sections of ice break away in quick succession.

Six-million-year-old ice discovered in Antarctica offers unprecedented window into a warmer Earth

Raising the Foro Drill, Allan Hills, Antarctica. 2022-2023.
Photo Credit: Julia Marks Peterson, COLDEX.

A team of U.S. scientists has discovered the oldest directly dated ice and air on the planet in the Allan Hills region of East Antarctica.

The 6-million-year-old ice and the tiny air bubbles trapped inside it provide an unprecedented window into Earth’s past climate, according to a new study published today in the Proceedings of the National Academy of Sciences.

The oldest ice sample from Allan Hills dated by researchers clocks in at 6 million years, from a period in Earth’s history where abundant geological evidence indicates much warmer temperatures and higher sea levels compared to today.

Beavers Impact Ecosystems Above and Below Ground

Photo Credit: Gennady Zakharin

Above ground, we can see changes wrought by beaver ponds such as increases in biodiversity and water retention. But UConn Department of Earth Sciences researcher Lijing Wang says we have a limited understanding of how they impact what happens beneath the ground. In research published in Water Resource Research, Wang and co-authors study how water moves through the soils and subsurface environment and detail new insights into how beaver ponds impact groundwater.

Groundwater can be an important source of water for streams, especially late in a dry summer, it may be the only source of water sustaining a stream, says Wang, and researchers are interested in understanding if and how beaver ponds impact groundwater as these details are important to consider for water management and restoration efforts.

Retreating Glaciers May Send Fewer Nutrients to the Ocean

Northwestern Glacier in Alaska has retreated approximately 15 kilometers (nine miles) since 1950.
Photo Credit: Kiefer Forsch/Scripps Institution of Oceanography.

The cloudy, sediment-laden meltwater from glaciers is a key source of nutrients for ocean life, but a new study suggests that as climate change causes many glaciers to shrink and retreat their meltwater may become less nutritious. 

Led by scientists at UC San Diego’s Scripps Institution of Oceanography, the study finds that meltwater from a rapidly retreating Alaskan glacier contained significantly lower concentrations of the types of iron and manganese that can be readily taken up by marine organisms compared to a nearby stable glacier. These metals are scarce in many parts of the ocean including the highly productive Gulf of Alaska, and they are also essential micronutrients for phytoplankton, the microorganisms that form the base of most marine food webs.

Microbes at Red Sea vents show how life and geology shape each other

Microscopic images of the studied microbes.
Image Credit: Courtesy of King Abdullah University of Science and Technology

A new study led by King Abdullah University of Science and Technology (KAUST) Professor Alexandre Rosado has revealed an unusual microbial world in the Hatiba Mons hydrothermal vent fields of the central Red Sea, a site first discovered by one of his co-authors and colleagues, Assistant Professor Froukje M. van der Zwan. 

Published in Environmental Microbiome, the study delivers the first "genome-resolved" analysis of these hydrothermal systems, providing an unprecedented view into both the types of microbes present and the metabolic functions that sustain them. 

“Microbes from the Hatiba Mons fields show remarkable metabolic versatility,” said KAUST Ph.D. student and lead author of the study, Sharifah Altalhi. “By understanding their functions, we can see how life shapes its environment, and how geology and biology are deeply intertwined in the Red Sea.” 

Arctic in Transition: Greenland’s Caves Preserve Ancient Climate Archive

Inside the Cove Cave, northern Greenland: A team of Innsbruck scientists studies deposits from a time when the Arctic was much warmer than today.
Photo Credit: Robbie Shone

In a remote cave in northern Greenland, a research team led by geologists Gina Moseley, Gabriella Koltai, and Jonathan Baker have discovered evidence of a significantly warmer Arctic. The cave deposits show that the region was free of permafrost millions of years ago and responded sensitively to rising temperatures. The findings, published in Nature Geoscience, provide new insights into past climate conditions and their relevance for today’s climate protection efforts.

Understanding Earth’s climate during earlier warm periods is key to predicting how it may change in the future. One particularly revealing time is the Late Miocene, which began about 11 million years ago. During this period, Earth’s distribution of land and ocean was similar to today, and both temperatures and atmospheric CO₂ levels were comparable to projections for the coming decades. Although the Arctic is known to be highly sensitive to climate change, its environmental conditions during the Late Miocene have remained poorly understood.

What Is: Extinction Level Events

A Chronicle of Earth's Biotic Crises and an Assessment of Future Threats
Image Credit: Scientific Frontline

Defining Biotic Catastrophe

The history of life on Earth is a story of breathtaking diversification and innovation, but it is punctuated by chapters of profound crisis. These are the extinction level events—catastrophes of such magnitude that they fundamentally reset the planet's biological clock. Popular imagination often pictures a single, sudden event, like the asteroid that sealed the fate of the dinosaurs. The geological reality, however, is more complex and, in many ways, more instructive for our current era. Understanding these events requires a rigorous scientific framework that moves beyond simple notions of species loss to appreciate the systemic collapse of entire global ecosystems.

New study finds large fluctuations in sea level occurred throughout the last ice age, a significant shift in understanding of past climate

Photo Credit: Michael Chen

Large changes in global sea level, fueled by fluctuations in ice sheet growth and decay, occurred throughout the last ice age, rather than just toward the end of that period, a study published this week in the journal Science has found.

The findings represent a significant change in researchers’ understanding of how the Pleistocene – the geological period from about 2.6 million to 11,700 years ago and commonly known as the last ice age – developed, said Peter Clark Link is external, a paleoclimatologist at Oregon State University and the study’s lead author.

“This is a paradigm shift in our understanding of the history of the ice age,” said Clark, a university distinguished professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

During the last ice age, Earth experienced cycles of dramatic shifts in global sea level caused by the formation and melting of large ice sheets over northern areas of North America and Eurasia. These changes are recorded in the shell remains of microscopic marine organisms called foraminifera, which are found in ocean sediment and collected by drilling cores, giving scientists an important record of past climate history.

Geologists discover the first evidence of 4.5-billion-year-old “proto-Earth”

“This is maybe the first direct evidence that we’ve preserved the proto Earth materials,” says Nicole Nie. An artist’s illustration shows a rocky proto Earth bubbling with lava.
Image Credit: MIT News; iStock
(CC BY-NC-ND 4.0)

Scientists at MIT and elsewhere have discovered extremely rare remnants of “proto-Earth,” which formed about 4.5 billion years ago, before a colossal collision irreversibly altered the primitive planet’s composition and produced the Earth as we know today. Their findings, reported today in the journal Nature Geosciences, will help scientists piece together the primordial starting ingredients that forged the early Earth and the rest of the solar system.

Billions of years ago, the early solar system was a swirling disk of gas and dust that eventually clumped and accumulated to form the earliest meteorites, which in turn merged to form the proto-Earth and its neighboring planets.

In this earliest phase, Earth was likely rocky and bubbling with lava. Then, less than 100 million years later, a Mars-sized meteorite slammed into the infant planet in a singular “giant impact” event that completely scrambled and melted the planet’s interior, effectively resetting its chemistry. Whatever original material the proto-Earth was made from was thought to have been altogether transformed.