Reviews & Analysis

Deep overturning circulation in the North Atlantic strongly influences the global climate system. Combined proxy record compilations and modelling refine our understanding of the behaviour of this circulation over the last 20,000 years.

Subaqueous glacier mass losses are not accounted for by traditional geodetic mass balance calculations. Estimates based on proglacial lake volume changes revealed that the mass loss of glaciers terminating into lakes in the greater Himalaya during 2000−2020 was previously underestimated by approximately 6.5%, with the largest underestimation in the central Himalaya.

The Montreal Protocol has successfully guided the world’s transition from chlorofluorcarbons that deplete ozone to hydrofluorocarbons that pose no direct threat to the ozone layer. A study suggests that a recent rise in atmospheric chlorofluorcarbons is linked to the inadvertent release of these gases during the production of hydrofluorocarbons.

A field-based study of 4.5 years of whole-soil warming reveals that warming stimulates loss of structurally complex organic carbon at the same rate as that for bulk organic carbon in subsoil.

The devastating intensity of exceptional floods in some rivers can be anticipated, and surprisingly traces back to the river basins themselves, rather than the amount of rain they receive.

The El Niño Southern Oscillation strongly impacts climate, but its variability remains difficult to predict. A conceptual model based on shifting circulation patterns offers a simple explanation for this complex behaviour.

Long-lasting eruptions of some subduction zone volcanoes may be regulated by their magma sources in the mantle. This suggests that direct connections between the mantle and surface are possible through a relatively thick crust.

Numerical simulations show that convection in the mantle shapes the long-term structure of Earth’s magnetic field. The mantle influences the magnetic field by imposing a pattern of cooling that controls the dynamics of fluid flow at the top of the outer core.

Satellite observations show that 24.1% of tropical moist forests are degraded. In addition to the warming effects of the release of carbon from biomass, satellite data suggest that degradation could also increase the land surface temperatures of the affected regions. This biophysical feedback could hinder forest restoration initiatives.

A remotely-operated underwater vehicle was used to map the ice, ocean, and seafloor conditions near the point where the floating Ross Ice Shelf meets the seafloor, also known as the grounding line. The study identified refreezing crevasses and geomorphological signatures of past grounding line retreat.

Satellite observations reveal that glaciers on the west coast of the Antarctic Peninsula flow 12% faster on average in summer than in winter. These increased flow speeds are attributed to a combination of seasonal atmospheric and oceanographic forcing mechanisms.

Lake drainage due to permafrost thaw in the northern permafrost zone is occurring sooner than anticipated.

Satellite data are revolutionizing coastal science. A study revealing how the El Niño/Southern Oscillation impacts coastal erosion around the Pacific Rim shows what is possible.

A global analysis of seismic waves has identified a widespread sharp velocity anomaly at the base of the low seismic velocity zone that is consistent with partial melting, closing a decades-long debate about the origin of this zone.

Spacecraft observations and climate modelling have revealed how atmospheric waves, dust storms and atmospheric loss processes are coupled throughout the atmosphere of Mars.

Microbial death pathways affect the quantity and composition of microbial necromass and its associated soil organic carbon.

Seismic observations reveal that the Earth’s inner core oscillates with a period of approximately seven decades. The multidecadal periodicity coincides with that of several other geophysical observations, particularly the variations in the length of day and the Earth’s magnetic field, suggesting dynamic interactions between the major layers of the Earth.

The environmental sensors aboard the Perseverance rover on Mars are gathering meteorological data at Jezero crater. These data capture an active atmospheric surface layer that responds to multiple dynamical phenomena, ranging in spatial and temporal scales from metres to thousands of kilometres and from seconds to a Martian year, respectively.

Some coastal marshes may have a hard time building soil elevation under future climate conditions, although this may reduce methane emissions, according to four years of field manipulation of warming and elevated CO₂ in a coastal wetland.