Science · Latest research
Latest research
New studies and reports on the big ocean changes, newest first. Each summary is written from the paper’s abstract and every reference is checked against its publisher’s record. Inclusion is not endorsement: some findings are contested, and the topic pages explain how they fit with the rest of the evidence.
Global Red List of Coral Reef Ecosystems (IUCN Red List of Ecosystems global coral reef assessment)
The first global Red List of Ecosystems assessment of coral reefs lists 96% of shallow-reef ecoregions as Critically Endangered, facing an extremely high risk of collapse by 2075.
IUCN, International Union for Conservation of Nature
Emissions Gap Report 2026
UNEP projects about 2.8 °C of warming by 2100 under current policies and 2.6–2.7 °C if pledges are met, and now measures the gap against a lowest-overshoot 1.5 °C pathway.
UNEP, United Nations Environment Programme · doi:10.59117/20.500.11822/50038
A Bering Sea marine heatwave triggers unprecedented crab hybridization, challenging fisheries management
Seven years after a Bering Sea marine heatwave, hybrid snow × Tanner crab abundance rose 13-fold, driven by the heatwave-induced snow crab collapse, exposing gaps in fisheries management.
Fedewa, E. J. et al., Proceedings of the National Academy of Sciences · doi:10.1073/pnas.2625670123
Ocean thermal inertia sustains a tropical Pacific mean state shift under net zero
In climate model runs, the tropical Pacific shifts to an El Niño-like mean state with warming and stays there for centuries after net zero, sustained by Southern and deep-ocean warming.
Sengupta, A. et al., Communications Earth & Environment · doi:10.1038/s43247-026-04082-x
Sea-level contribution from Thwaites Glacier doubles in an observation-constrained ice-sheet model
Calibrated to three decades of observations, a Thwaites Glacier model projects ridge unpinning as early as 2038 and up to 30 mm sea-level rise by 2100, about double earlier projections.
Poinelli, M. et al., Nature Communications · doi:10.1038/s41467-026-77976-1
Recent strengthening of eastern Pacific ENSO in the last millennium paleorecord
Galápagos coral records spanning the past millennium show a recent rise in eastern Pacific temperature variability, caused by stronger El Niño events, that exceeds simulated natural variability.
Cole, J. E. et al., Science · doi:10.1126/science.ady2660
Mass balance of the Greenland and Antarctic ice sheets from the 1970s to 2023
Combining 42 independent satellite estimates, the study finds Greenland and Antarctica lost 11,309 ± 565 billion tonnes of ice between 1979 and 2023, 84% of it through glacier dynamics.
Otosaka, I. N. et al., Scientific Data · doi:10.1038/s41597-026-08088-0
Status of Coral Reefs of the World: 2025
Drawing on 36,886 survey sites in 124 countries, global hard coral cover fell 9.5% in relative terms between 1980–2009 and 2020–2024, including an 8.9% drop in 2023–24.
González-Rivero, M. et al. (eds), Global Coral Reef Monitoring Network (GCRMN) / ICRI · doi:10.59387/LFPR6347
Persistent Warming and Reduced Freshening of the Abyssal Southern Ocean
Observations from 1985–2024 and model projections show Antarctic Bottom Water keeps thinning and the abyssal Southern Ocean keeps warming, while meltwater-driven abyssal freshening is slowing and expected to reverse.
Gunn, K. L. et al., Journal of Geophysical Research: Oceans · doi:10.1029/2025JC023688
Observed Trends in the Tropical Pacific Zonal Sea Surface Temperature Gradient Are Statistically Significant Based on Multiple Null Hypotheses
Testing all observed trends since 1870 against multiple null hypotheses, the study finds the strengthening east–west tropical Pacific temperature gradient since 1950 is unlikely to reflect internal variability alone.
Sugiura, I. et al., Journal of Climate · doi:10.1175/JCLI-D-25-0460.1
Failure to track a stable AMOC state under rapid climate change
In a climate model, the AMOC stays stable to 5.5 °C warming under slow CO2 increases yet collapses near 2 °C under faster ones, showing the rate of warming matters.
van Westen, R. M. et al., Nature Climate Change · doi:10.1038/s41558-026-02730-w
Near-total loss of buttressing stresses observed on Pine Island Ice Shelf, West Antarctica
Velocity observations from 2015–2024 show Pine Island Ice Shelf lost nearly all its buttressing after calving and shear-margin breakup, likely foreshadowing faster grounding-line retreat and sea-level contribution.
Wells-Moran, S. et al., Proceedings of the National Academy of Sciences · doi:10.1073/pnas.2602994123
Paleorecords inform the limits of Indo-Pacific coral reef survival under accelerating sea-level rise
Holocene records from 92 Indo-Pacific sites suggest 76% of reefs cannot keep pace with sea-level rise under high emissions; reef growth very likely fails above about 5.3 mm per year.
Ramos, R. D. et al., Nature Communications · doi:10.1038/s41467-026-74612-w
The State of World Fisheries and Aquaculture 2026
FAO reports record aquatic production of 235 million tonnes in 2024, with aquaculture providing 53%, while the share of marine stocks fished sustainably fell to 62.4% in 2023.
FAO, Food and Agriculture Organization of the United Nations · doi:10.4060/cd8357en
Indicators of Global Climate Change 2025: annual update of key indicators of the state of the climate system and human influence
Annual indicators show human-induced warming reached 1.37 °C in 2025, rising 0.27 °C per decade; Earth's energy imbalance has more than doubled and marine heatwave days have tripled since 1991.
Forster, P. M. et al., Earth System Science Data · doi:10.5194/essd-18-3889-2026
Critical dependence of global ocean heat monitoring on the ocean observing system
The study shows that reducing data from the Global Ocean Observing System would substantially degrade monitoring of ocean heat content, and calls for sustained international and national commitments.
Zhu, Y. et al., Nature Climate Change · doi:10.1038/s41558-026-02661-6
Observational constraints project a ~50% AMOC weakening by the end of this century
Observational constraints on CMIP6 models give AMOC weakening of 51 ± 8% by 2100 under SSP2-4.5, about 60% more than the multimodel mean, mainly via South Atlantic salinity bias correction.
Portmann, V. et al., Science Advances · doi:10.1126/sciadv.adx4298
A risk assessment framework for interacting tipping elements
A probabilistic network model of interacting tipping elements finds interactions mostly destabilise the climate system; coral reefs are likely to collapse by 2100 even under SSP1-1.9.
Bara, J. et al., Earth System Dynamics · doi:10.5194/esd-17-333-2026
Collapse of the Atlantic meridional overturning circulation would lead to substantial oceanic carbon release and additional global warming
In a fast Earth system model, AMOC collapse releases ocean carbon, raising CO2 by 47–83 ppm and adding about 0.2 °C of warming, while the Arctic cools about 7 °C.
Nian, D. et al., Communications Earth & Environment · doi:10.1038/s43247-026-03427-w
Future changes in seasonal drought in Australia
A 32-member hydrological ensemble projects more time in meteorological, hydrological and agricultural drought across Australia, especially in winter and spring and in populated farming regions.
Ukkola, A. M. et al., Hydrology and Earth System Sciences · doi:10.5194/hess-30-1463-2026
State of the Global Climate 2025
WMO confirms 2015–2025 as the 11 warmest years on record, with 2025 about 1.43 °C above pre-industrial and Earth's energy imbalance at a record high.
WMO, World Meteorological Organization · doi:10.59327/WMO/S/CRI/SOC/1
Wind-triggered Antarctic sea-ice decline preconditioned by thinning Winter Water
About 110,000 ocean profiles show thinning Winter Water in 2005–2015 preconditioned the 2015–2017 Antarctic sea-ice regime shift, which strong 2015 winds triggered by mixing warm subsurface water upward.
Spira, T. et al., Nature Climate Change · doi:10.1038/s41558-026-02601-4
Recent Observations of Thwaites Glacier, West Antarctica Are Consistent With High Rates of Loss in Next 50 Years
Two ice-sheet models calibrated to 2004–2017 surface elevation change project Thwaites Glacier losses of 180–200 Gt per year by 2067, comparable to today's Antarctic-wide mass loss.
Goldberg, D. N. et al., Geophysical Research Letters · doi:10.1029/2025GL118823
Marine protected areas marginally offset anthropogenic declines in tropical reef fish contributions to nature and people
Across 2,800 tropical reefs, human impacts sharply reduced fish-derived benefits, while marine protected areas offset only about 5% of the decline; only old, fully protected areas helped markedly.
Flandrin, U. et al., Nature Ecology & Evolution · doi:10.1038/s41559-026-03008-2
The Abrupt and Persistent Decline in Recruitment Success in Northeast Arctic Cod: A Review of Probable Causes
A review links the collapse in Northeast Arctic cod recruitment since 2006 to northward spawning shifts, reduced Calanus inflow and density effects, and recommends lower fishing pressure as a precaution.
Johannesen, E. et al., Fish and Fisheries · doi:10.1111/faf.70074
Abrupt Gulf Stream path changes are a precursor to a collapse of the Atlantic Meridional Overturning Circulation
In a high-resolution ocean model, the Gulf Stream jumps 219 km north decades before AMOC collapse; observations show a significant northward trend near Cape Hatteras, a possible early warning.
van Westen, R. M. & Dijkstra, H. A., Communications Earth & Environment · doi:10.1038/s43247-026-03309-1
Long-term warming reduces fish biomass, but heatwaves shift it
Across 33,990 Northern Hemisphere fish populations, long-term warming is linked to biomass declines, while heatwaves cut biomass up to 43% at warm range edges and raise it at cold edges.
Chaikin, S. et al., Nature Ecology & Evolution · doi:10.1038/s41559-026-03013-5
The implications of overshooting 1.5 °C on Earth system tipping elements—a review
Reviewing 1.5 °C overshoot, the authors find fast-responding systems such as coral reefs most vulnerable, and argue warming must peak below 2 °C and later return to about 1 °C.
Ritchie, P. D. L. et al., Environmental Research Letters · doi:10.1088/1748-9326/ae3cad
Coral Reef Protection May Help Avert Risks to People, Property, and Economic Activity Caused by Projected Reef Degradation
Projected degradation of southeast Florida's reefs would raise annual flood risk to people by 42% and to structures by 47%, adding about $850 million a year in damages and disruption.
Storlazzi, C. D. et al., Earth's Future · doi:10.1029/2025EF006255
Ocean Heat Content Sets Another Record in 2025
Upper 2,000 m ocean heat content rose by about 23 zettajoules in 2025, another record, even though global sea surface temperature dipped slightly from 2024 as La Niña developed.
Pan, Y. et al., Advances in Atmospheric Sciences · doi:10.1007/s00376-026-5876-0
Enduring impacts of El Niño on life expectancy in past and future climates
El Niño persistently slows gains in life expectancy across high-income Pacific Rim countries; under moderate emissions, projected losses reach 2.8 years by 2100, worth about US$35 trillion.
Xu, Y. et al., Nature Climate Change · doi:10.1038/s41558-025-02534-4
Antarctic Bottom Water in a changing climate
This review finds Antarctic Bottom Water has thinned by over 50 dbar per decade since the mid-1980s and abyssal overturning has slowed, trends expected to accelerate with more meltwater.
Rintoul, S. R. et al., Nature Reviews Earth & Environment · doi:10.1038/s43017-025-00750-2
From short-term uncertainties to long-term certainties in the future evolution of the Antarctic Ice Sheet
Calibrated ice-sheet ensembles project Antarctic sea-level contributions by 2300 of −0.09 to 1.74 m under low emissions and 0.73 to 5.95 m under very high emissions.
Coulon, V. et al., Nature Communications · doi:10.1038/s41467-025-66178-w
Concurrent warming, freshening and cessation of deep convection in the Labrador Sea raised its sea level to a record high
Altimetry, Argo and ship data show central Labrador Sea level rose to a record high in 2017–2025, driven by warming, unprecedented freshening and the halt of deep convection.
Yashayaev, I. & Zhang, Y., Nature Communications · doi:10.1038/s41467-025-65747-3
Global Ocean Observing System 2025 Status Report
GOOS reports progress in ocean observing but warns the system remains subcritical and at risk, with uneven coverage, declining buoy and ship observations, and reliance on few contributors.
GOOS (IOC-UNESCO), Global Ocean Observing System
Climate Refugia Could Disappear From Australia's Marine Protected Areas by 2040
Using 11 CMIP6 models, climate refugia in Australian waters disappear by 2040 if warming exceeds 1.8 °C, and marine protected areas are as exposed as unprotected waters.
Pidd, A. M. et al., Earth's Future · doi:10.1029/2025EF006457
The Global Tipping Points Report 2025
Over 160 authors conclude warm-water coral reefs are already crossing their thermal tipping point at 1.4 °C of warming, and the AMOC is at risk of collapse below 2 °C.
Lenton, T. M. et al. (eds), University of Exeter · doi:10.5281/zenodo.18163977
Recent and early 20th century destabilization of the subpolar North Atlantic recorded in bivalves
Bivalve shell records show two destabilisation episodes in the subpolar North Atlantic over 150 years: one before the 1920s regime shift and a stronger one since about 1950.
Arellano-Nava, B. et al., Science Advances · doi:10.1126/sciadv.adw3468
Rising dengue risk with increasing El Niño–Southern Oscillation amplitude and teleconnections
Across 57 countries, ENSO fluctuations explain 63% of dengue variation; the 2023–24 El Niño added an estimated 9.6 million cases, and warming could raise cumulative cases 39–82% this century.
Tian, Y. et al., Nature Communications · doi:10.1038/s41467-025-63655-0
Characterizing the Interannual Variability of North Atlantic Subpolar Overturning
The updated 2014–2022 OSNAP record shows any single boundary current captures about 30% of subpolar overturning variability, so a wide observing array across the eastern basin is needed.
Fu, Y. et al., Geophysical Research Letters · doi:10.1029/2025GL114672
Reduced Atlantic reef growth past 2 °C warming amplifies sea-level impacts
Fossil reef data from more than 400 western Atlantic sites indicate over 70% of reefs will be eroding by 2040, and nearly all by 2100 if warming exceeds 2 °C.
Perry, C. T. et al., Nature · doi:10.1038/s41586-025-09439-4
Adjusting the management of the Antarctic krill fishery to meet the challenges of the 21st century
After CCAMLR failed to renew spatial krill catch limits in 2024, the authors propose management based on krill recruitment variability and stock structure, using fishing vessels to collect data.
Meyer, B. et al., Proceedings of the National Academy of Sciences · doi:10.1073/pnas.2412624122
Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections
In CMIP6 runs extended beyond 2100, the AMOC falls to an extremely weak, shallow state in all high-emission models, preceded by a mid-century collapse of deep mixing.
Drijfhout, S. et al., Environmental Research Letters · doi:10.1088/1748-9326/adfa3b
Emerging evidence of abrupt changes in the Antarctic environment
This review finds emerging evidence of abrupt, interacting Antarctic changes, including a sea-ice regime shift, slowing overturning and possible West Antarctic ice-sheet tipping even under low emissions.
Abram, N. J. et al., Nature · doi:10.1038/s41586-025-09349-5
Climate change drives shifts in straddling fish stocks in the world’s ocean
Of 347 straddling fish stocks identified worldwide, at least 37% are projected to shift between national waters and the high seas by 2030, and 54% by 2050, under any scenario.
Palacios-Abrantes, J. et al., Science Advances · doi:10.1126/sciadv.adq5976
Little-to-no industrial fishing occurs in fully and highly protected marine areas
Satellite radar and AI show little to no industrial fishing in most fully and highly protected MPAs, with vessel density nine times lower than in unprotected national waters.
Raynor, J. et al., Science · doi:10.1126/science.adt9009
Global patterns and drivers of untracked industrial fishing in coastal marine protected areas
Combining vessel tracking with satellite imagery, industrial fishing was detected in 47% of coastal MPAs in 2022–2024, and two-thirds of detected vessels were not publicly tracked.
Seguin, R. et al., Science · doi:10.1126/science.ado9468
Rising surface salinity and declining sea ice: A new Southern Ocean state revealed by satellites
Satellites reveal rising surface salinity across the Southern Ocean since 2015, weakening stratification as Antarctic sea ice declined sharply and the Maud Rise polynya reappeared.
Silvano, A. et al., Proceedings of the National Academy of Sciences · doi:10.1073/pnas.2500440122
Assessment of Abrupt Shifts in CMIP6 Models Using Edge Detection
Edge detection across 57 CMIP6 models finds abrupt shifts in nine of ten subsystems, including the subpolar gyre; at 1.5 °C, six already show large-scale shifts in several models.
Terpstra, S. et al., AGU Advances · doi:10.1029/2025AV001698
Antarctic Ice Sheet tipping in the last 800,000 years warns of future ice loss
Simulations over 800,000 years show Antarctic ice-sheet hysteresis and tipping, with West Antarctic collapse adding over 4 m of sea level at little or no ocean warming above today.
Chandler, D. M. et al., Communications Earth & Environment · doi:10.1038/s43247-025-02366-2
Strong 2023–2024 El Niño generated by ocean dynamics
The strong 2023–24 El Niño arose mainly from ocean heat built up during the preceding prolonged La Niña, with muted wind feedback, which made it predictable at long lead times.
Peng, Q. et al., Nature Geoscience · doi:10.1038/s41561-025-01700-9
Warming of +1.5 °C is too high for polar ice sheets
Multiple lines of evidence suggest today's warming, if sustained, would likely cause several metres of sea-level rise over centuries; a safe limit for ice sheets may be nearer 1 °C.
Stokes, C. R. et al., Communications Earth & Environment · doi:10.1038/s43247-025-02299-w
Ambiguity of early warning signals for climate tipping points
Common statistical early warning signals of tipping are ambiguous, since resilience can decline without a tipping point; the authors call for better tests and propose a probabilistic method.
Rietkerk, M. et al., Nature Climate Change · doi:10.1038/s41558-025-02328-8
Restoration cannot be scaled up globally to save reefs from loss and degradation
A global analysis finds coral restoration sites cluster near settlements, outcomes ignore key ecological predictors, and most sites face severe bleaching risk by mid-century, limiting global scale-up.
Mulà, C. et al., Nature Ecology & Evolution · doi:10.1038/s41559-025-02667-x
Abrupt Changes in the Timing and Magnitude of the North Atlantic Bloom Over the 21st Century
Two ocean models project the North Atlantic spring bloom halving this century under all scenarios as winter mixing weakens, with abrupt change and a 30-day-plus timing shift at high resolution.
Kelly, S. et al., Journal of Geophysical Research: Oceans · doi:10.1029/2024JC022284
Record sea surface temperature jump in 2023–2024 unlikely but not unexpected
The 2023–24 jump in global sea surface temperature was a 1-in-512-year event under the current warming trend, practically impossible without it, and climate models can simulate such jumps.
Terhaar, J. et al., Nature · doi:10.1038/s41586-025-08674-z
Continued Atlantic overturning circulation even under climate extremes
Across 34 climate models, wind-driven Southern Ocean upwelling sustains a weakened AMOC under extreme greenhouse and freshwater forcing, suggesting a full collapse this century is unlikely.
Baker, J. A. et al., Nature · doi:10.1038/s41586-024-08544-0
Present-day mass loss rates are a precursor for West Antarctic Ice Sheet collapse
With present-day ocean forcing held for centuries, a model matched to observed mass loss collapses Thwaites and Pine Island glaciers in every run, raising sea level at least a metre.
van den Akker, T. et al., The Cryosphere · doi:10.5194/tc-19-283-2025
Hybrid coral reef restoration can be a cost-effective nature-based solution to provide protection to vulnerable coastal populations
Modelling 1,005 km of reef coast in Florida and Puerto Rico shows restoring up to 20% of reefs gives flood-reduction benefits exceeding costs, with the largest gains for vulnerable people.
Storlazzi, C. D. et al., Science Advances · doi:10.1126/sciadv.adn4004
Atlantic overturning inferred from air-sea heat fluxes indicates no decline since the 1960s
Using air–sea heat fluxes as a model-validated proxy, the study finds the decadal-mean AMOC at 26.5°N did not weaken between 1963 and 2017, despite substantial variability.
Terhaar, J. et al., Nature Communications · doi:10.1038/s41467-024-55297-5