Open Access Notables
The Weak Land Carbon Sink Hypothesis
Randerson et al., Science Advances
Over the past three decades, assessments of the contemporary global carbon budget have consistently reported a strong net land carbon sink. This review examines the evidence supporting this paradigm and quantifies differences in global and Northern Hemisphere estimates of the net land sink derived from atmospheric inversion and satellite-derived vegetation biomass time series. The analysis supports a hypothesis that the net land sink is substantially weaker than commonly reported.
Globally, the estimated net land carbon sink is 0.8 ± 0.7 petagrams of carbon per year from 2000 through 2019, which is nearly half the estimate by the Global Carbon Project. With concurrent adjustments to ocean (+8%) and fossil fuel (−6%) fluxes, a budget is developed that partially reconciles key constraints from vegetation carbon, the north-south CO₂ gradient, and O₂ trends. Potential model modifications and approaches for testing this hypothesis are discussed.
The Spatial Extent of Heat Waves Has Changed Over the Past Four Decades
Skinner et al., Communications Earth & Environment
The spatial extent of extreme heat events impacts the total exposure of people and natural systems to heat-related stresses, stressing water, energy, and emergency resources. This study quantifies how the contiguous area of individual heat waves varies by heat wave type, season, and observed climate change using the Berkeley Earth Surface Temperature Dataset.
Findings include that cold season heat waves in mid to high latitudes cover 1.25 to 3 times larger areas than warm season events, and daytime heat waves affect 1.25 to 2 times the area of nighttime heat waves. In tropical regions, the reverse is true. Overall, heat wave size has increased by 1.5 to 2 times across most mid-latitude land areas recently. Increases in dry soil anomalies and lower tropospheric subsidence events in some locations may also contribute to larger heat waves.
Systematic Attribution of Heatwaves to the Emissions of Carbon Majors
Quilcaille et al., Nature
This work expands event-based attribution frameworks to assess how climate change, driven by emissions from 180 carbon majors (fossil fuel and cement producers), has influenced historical heatwaves from 2000 to 2023. Results show climate change has made these 213 heatwaves more likely and more intense.
Since 1850–1900, median heatwaves during 2000–2009 are about 20 times more likely, increasing to 200 times more likely during 2010–2019. One-quarter of the events would have been virtually impossible without climate change. Carbon majors contributed to half the increase in heatwave intensity since the preindustrial era. Individual carbon majors’ emissions have enabled between 16 and 53 heatwaves that would have been nearly impossible preindustrial climate conditions, underscoring growing climate change accountability needs for these actors.
Health Losses Attributed to Anthropogenic Climate Change
Carlson et al., Nature Climate Change
Attribution science over the last decade demonstrates that climate change causes substantial death, disability, and illness worldwide. However, studies have primarily focused on high-income populations and mainly quantify heat and extreme weather outcomes. The need remains to develop a clearer global picture of climate change’s health burden to encourage policymakers to address the climate crisis as a public health emergency.
Highlights from Government and NGO Reports
China’s Green Leap Outward: The Rapid Scaleup of Overseas Chinese Clean-Tech Manufacturing Investments
Xiaokang Xue and Mathias Larsen, Net Zero Policy Industrial Lab, Johns Hopkins University
Since 2022, Chinese green technology manufacturers have accelerated overseas investments past USD 220 billion across batteries, solar, wind, new energy vehicles (NEVs), and green hydrogen sectors in 54 countries worldwide. Chinese firms have pledged at least USD 227 billion in green manufacturing projects, approaching USD 250 billion. This unprecedented surge surpasses the USD 200 billion invested by the US during the Marshall Plan era, signaling a major reshaping of the global clean-tech manufacturing landscape.
Taking Stock 2025
King et al., Rhodium Group
The first seven months of the second Trump administration and 119th Congress show a sharp shift in US energy and climate policy, with measures hostile to wind, solar, and electric vehicles, while promoting fossil fuel production. Despite this, the US is projected to reduce greenhouse gas (GHG) emissions by 26–41% by 2040 relative to 2005. However, the pace of decarbonization is slower than prior years in the high emissions scenario but accelerates in mid and low emissions scenarios, representing meaningful shifts in trajectories.
Additional Agency and NGO Reports
- China Energy Transition Review 2025 (Ember): Highlights China’s rapid clean energy growth and implications globally.
- WHO Global Water, Sanitation and Hygiene Annual Report 2024: Documents improvements in global access to safe water, sanitation, and hygiene services, linking them to reduced diarrheal disease.
- New Zealand Energy Quarterly June 2025: Reports on hydro generation declines offset by other renewables; overall renewable electricity generation share increased to 84.1%.
- Global Hydrogen Compass 2025 (Hydrogen Council & McKinsey): Notes over USD 110 billion committed in clean hydrogen investments and project pipelines through 2030.
- EIPC Interregional Transmission Transfer Capability Study Report: Analyzes interregional power transfer capabilities under various weather conditions in the Eastern US.
- Iowa Electric Generation Condition of the State 2025: Highlights Iowa’s renewable leadership but ongoing reliance on coal generation and environmental impacts.
Selected Open Access Research Highlights
Physical Science of Climate Change and Effects
- Global Water Cycle Pattern Amplification, Lyu et al., 10.1029/2024jc022278
- Neglecting Land–Atmosphere Feedbacks Overestimates Climate-Driven Evapotranspiration Increases, Zhou & Yu, Nature Climate Change
- Planetary Albedo and Reflected Shortwave Flux: Mechanisms and Projections, Li et al., Earth
Observations of Climate Change and Effects
- Coastal Flooding in Southwest Florida During Hurricanes Irma and Ian, Paramygin & Sheng, npj Natural Hazards
- Global Increase of Tropical Cyclone Precipitation Rate Toward Coasts, Qi et al., Geophysical Research Letters
- Recent Intensification of Arctic Winter Anticyclonic Circulation Linked to Sea Ice Loss, Liu et al., JGR Atmospheres
- Systematic Attribution of Heatwaves to Carbon Majors, Quilcaille et al., Nature
- The Spatial Extent of Heat Waves Over Four Decades, Skinner et al., Communications Earth & Environment
Cryosphere and Climate Change
- Greenland Ice Sheet Runoff Reduced by Meltwater Refreezing, Cooper et al., Nature Communications
- Meltwater Ponding’s Radiative Effect on Greenland Ice Sheet Surface, Ryan et al., Nature Communications
- Evolution of Glacial Lakes and GLOFs in Tierra del Fuego, Izagirre et al., Frontiers in Earth Science
Decarbonization and Energy Systems
- Advancing Circularity in Battery Systems for Renewable Energy, Munonye et al., Advanced Energy and Sustainability Research
- Research Trends in Total Cost of Ownership for Electric Vehicles, al Irsyad et al., Energy for Sustainable Development
- China’s Green Leap Outward in Clean-Tech Manufacturing Investments, Xue & Larsen, Net Zero Policy Industrial Lab
Climate Change Economics and Policy
- Assessing Effectiveness of Municipal Climate Actions for Residential Energy Retrofits, Jadidi et al.
- Closing Emission Gaps in Border Carbon Adjustments for Chemicals and Plastics, Minten et al., Nature Sustainability
- Gender and Socio-Economic Determinants of Clean Energy Adoption in Uganda, Tereka et al., Energy for Sustainable Development
Climate Change and Human Health
- Communicating Climate Change Impact on Health, Zhang et al., Environmental Communication
- Health Losses Attributed to Anthropogenic Climate Change, Carlson et al., Nature Climate Change
- Mechanistic Modeling for Climate-Informed Dengue Forecasting, Yasanayake et al., GeoHealth
Informed Opinions and Editorial Highlights
- Climate Impacts Are Real — Denying This Is Self-Defeating, Editorial, Nature
- Climate Research in the Global South, Editorial, Nature Communications
- The Role of Artificial Intelligence in Climate Change Scientific Assessments, Al Khourdajie, PLOS Climate
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