Volume 5 Issue 4, April 2024

To explore career opportunities outside of academia, Nature Reviews Earth & Environment interviewed Giuliana Viglione about their career path from a graduate student to a climate journalist at Carbon Brief.

Lisbett Materano highlights how urban dust samples can be used to identify environmental and health risks from air pollution.

Hao Li explains how groundwater and ice core samples are dated using krypton-81 atom trap trace analysis.

In 2023, global full-depth ocean heat content (OHC) reached a record increase of 464 ± 55 ZJ since 1960, with strong heat gain observed in the Southern and Atlantic Oceans. OHC was 16 ± 10 ZJ higher than in 2022, continuing the long-term increasing trend that started in 1960.

Antarctic sea ice extent was the lowest on record in 2023, with an annual mean of 9.81 million km², beating the previous minimum of 2022. Arctic sea ice extent was also low, with an annual mean of 10.49 million km², but did not break any records.

Wildfires burned 384 Mha of land in 2023, the highest since 2017 but 5% lower than the 2001–2022 average. These fires emitted an estimated 2,524 Tg C, 30% of which came from Canada’s record fire season.

Global greening continued into 2023, reaching near-record values that were dominated by regional enhancement in the mid-western USA, Europe, northern Australia and parts of equatorial Africa. In contrast, climatic events contributed to browning signals in Russia, Canada, Mexico and tropical drylands.

Multiple relentless heatwaves occurred in 2023, with much of the world experiencing at least 20 more heatwave days than the 1991–2020 average. Prominent and record-breaking events included exceptional wintertime and spring heat in South America, large heatwaves over Europe, Africa and Asia, and a prolonged event over south-eastern USA and Central America.

Global terrestrial water storage (TWS) anomalies reached a record low of –9.94 cm in 2023, decreasing 0.80 cm from 2022. These reductions largely reflect ongoing TWS losses from glacial melt and groundwater use for irrigation, offset by gains in central and eastern Antarctica and La Niña-related tropical wetting.

2023 saw a multitude of extreme precipitation events across the globe, causing flash flooding, countless fatalities and huge economic losses. Fuelled by a combination of a strong El Niño, record ocean warmth and anthropogenic warming, these events highlight the ongoing risks posed by extreme precipitation in a warming climate.

Global CO₂ emissions for 2023 increased by only 0.1% relative to 2022 (following increases of 5.4% and 1.9% in 2021 and 2022, respectively), reaching 35.8 Gt CO₂. These 2023 emissions consumed 10–66.7% of the remaining carbon budget to limit warming to 1.5°C, suggesting permissible emissions could be depleted within 0.5–6 years (67% likelihood).

In 2023, national and international climate policy advanced in many areas but also faced substantial domestic hurdles in others. Countries agreed on new global initiatives and many major emitters expanded national climate policies. However, others rolled back existing policies and continued to support fossil fuels, slowing down global progress.

Grapes produced for winemaking are highly susceptible to changes in climate, particularly extreme heat and drought. This Review examines the changing geography of existing and emerging winegrowing regions, and recommends adaptation measures to increasing heat and modified drought, pest and disease pressure.

Rainfall events are becoming less frequent but more intense with anthropogenic warming. This Review explores the consequences of these changes on plants and investigates how and why plant responses appear to broadly differ between dry and wet ecosystems.

Accurate and timely food production data are needed to promote food security and sustainability, but data scarcity exists across national and international levels. This Review examines data availability and reliability for crops, livestock and aquatic food production and recommends solutions to address data scarcity.

The use of groundwater with high levels of geogenic contaminants, such as arsenic, has caused severe health impacts and mortality in communities globally. This Review examines the drivers and occurrence of groundwater contamination by naturally occurring arsenic, fluoride, selenium and uranium.