Reviews & Analysis

Megathrust earthquakes along subduction zones present significant hazards. Evidence from the South Chile subduction zone suggests that the structure and fluid distribution of the megathrust interface governs the size and timing of large earthquakes.

Marine microfossil assemblages refine sea surface temperature patterns and yield insights into discrepancies between paleoclimate models of the last ice age and observations.

Three decades of meteorological observations show that Himalayan glaciers have been cooling because of intensified downslope winds, in contrast to the warming observed elsewhere in the region.

A geochemical study of an ancient mass-extinction event shows that only moderate expansion of oxygen-deficient waters along continental margins is needed to decimate marine biodiversity. This finding provides a stark warning of the possible consequences of human-driven ocean deoxygenation on life in Earth’s shallow oceans.

Authorship statistics from ice core science suggest that collaboration between women is a key factor in closing gender gaps in scientific publishing.

Analysis of sea temperatures using a four-dimensional spatio-temporal framework has revealed a great number of marine heatwaves occurring globally below the sea surface. These extreme events, which threaten the ecologically important epipelagic zone, have occurred increasingly frequently during the past three decades owing to ocean warming.

Identifying the metal micronutrients required by early life could help to illuminate how primitive organisms arose, but which metals were biologically available in ancient seawater has not been determined. A new experimental framework suggests how the precipitation of iron minerals from seawater reduced the availability of key metals, particularly zinc, copper and vanadium.

Deep-sea acidity data combined with ice-core carbon dioxide records reveal that an interplay between the two polar regions modulates ocean ventilation through various modes. These modes explain past variations in deep-sea carbon storage and atmospheric carbon dioxide on millennial timescales.

H₂, which is formed by the oxidation of iron in rocks, was likely a critical source of energy for early life. Analysis of natural rock samples from 3.5–2.7 billion-year-old komatiites, combined with geochemical data from a global database, quantifies the amount of H₂ likely to have been produced in Earth’s ancient oceans.

The CLOUD experiment provides important insights into new particle formation in different atmospheric environments.

Megafloods are rare and hence difficult to predict. However, using a collation of historical flood observations across Europe, it is now shown that recent megafloods could have been anticipated — local surprises are in fact not surprising at the continental scale.

Discrepancies between model simulations and proxy reconstructions of regional multidecadal to centennial climate variability are primarily due to climate model deficiencies, which might also impact future projections, according to a synthesis of recent work.

Swath radar maps of the subglacial landscape reveal how Antarctica’s geologic history has influenced the evolution of the ice sheet. The findings indicate the role of past interior ice streams in shaping ice-sheet growth and flow from Hercules Dome.

From a stalagmite that grew 14,000–8,500 years ago, isotopic data provide a detailed history of groundwater infiltration associated with a strengthening North American monsoon, as the climate transitioned from a cool dry late-glacial period into a warmer and wetter Early Holocene.

Accurate estimates of the land carbon sink are vital for informing climate projections and net-zero policies. Application of a strict filtering method to microwave satellite data enabled the evaluation of global vegetation biomass carbon dynamics for 2010–2019. The results highlight the role of demography in driving forest carbon gains and losses.

There are two competing hypotheses for the origin of oceanic plateaus: plume versus plate. Thermodynamic modelling of magmatism at Shatsky Rise, in the Pacific Ocean, now suggests that neither mechanism is adequate on its own and in fact plume–ridge interaction is required to explain the formation of this ocean plateau.

Exoenzymes produced by heterotrophic microorganisms early in Earth history helped unlock previously unavailable organic matter and transformed ocean geochemistry.

Phosphorus from intensive agriculture contributes to increased algal blooms, threatening ecosystems and drinking water sources. We found increasing dissolved phosphorus concentrations in more than 170 Great Lakes Basin streams, despite stable or decreasing total phosphorus levels. Higher latitudes experienced greater relative increases, potentially due to warmer winters and altered flow pathways.

Glacier ice contains high-pressure air bubbles, which burst into seawater as ice melts at tidewater glacier termini. Laboratory measurements found that these bubbles double the rate of ice melt. Theoretically, this effect could be even larger in a real glacier. However, bursting bubbles are currently neglected in models projecting sea level rise.

Analysis of mineral inclusions in magmas that crystallized before and after the Great Oxidation Event reveals marked changes in the oxidation state of sulfur — owing to the recycling into the mantle of sediments that had been geochemically altered at the surface by atmospheric events.