Volume 16 Issue 4, April 2023

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.

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.

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.

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.

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.

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.

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.

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.

Analysis of lunar soils sampled by the Chang’e-5 mission suggests that impact glass beads may host a substantial inventory of solar wind-derived water on the Moon’s surface.

The lunar basalts sampled by the Chang’e-5 mission originated from melting of a clinopyroxene-rich mantle source enhanced in radioactive elements, potentially explaining this late lunar volcanism, according to sample analysis and crystallization modelling.

Levels of five chlorofluorocarbons rose in the atmosphere from 2010 to 2020 despite their production being banned by the Montreal Protocol, probably arising as by-products of hydrofluorocarbon production, according to analysis of abundance and emissions data.

Climate simulations suggest that the contribution of methane to climate warming and wetting due to absorption of long-wave radiation is partially counteracted by short-wave absorption.

Climate model simulations suggest that atmospheric and oceanic circulation are modified by spatially uniform changes in global sea level.

A simple conceptual model suggests that the complex behaviour of the El Niño/Southern Oscillation can be explained by zonal shifts in the Walker circulation.

Accounting for subaqueous melting from lake-terminating glaciers increases estimated glacier mass loss across the Himalaya by 7% over the past 20 years, according to analysis of satellite observations and bathymetric measurements.

Extreme flood risk can be predicted based on stream network organization and flow regime, according to analysis of hydroclimatic observational records.

Structurally complex polymeric compounds, such as pyrogenic carbon, that have been previously considered long-term carbon sinks in soils can rapidly be lost by decomposition at warmer temperatures, according to 4.5 years of whole-soil warming experiments.

The Atlantic meridional overturning circulation was shallow and weak during the Last Glacial Maximum, and water masses took time to adjust to circulation shifts during the Last Deglaciation, according to a reassessment of proxy records and model simulations.

Meltwater discharge to the mid-Holocene North Atlantic disrupted decadal climate variability, suggesting future melting on Greenland may hinder climate predictability in the region, according to an annually laminated lake-sediment record and transient model simulations.

Small-scale compositional alteration of the mantle wedge by fluids may regulate eruptive activity of individual arc volcanoes, according to an analysis of the isotopic composition of ashes erupted by Tungurahua volcano in Ecuador from 1999 to 2016.

Intraplate volcanoes erupt lower volumes of more diverse magma and have increasingly complex magmatic architectures as the heat flux from the driving mantle plume wanes, according to an analysis of a continental hotspot chain in eastern Australia.

The pattern of heat flow across the core–mantle boundary results in longitudinal differences in geomagnetic field behaviour, according to geodynamo modelling.