MIT News December 4, 2024 Anthropogenic methane emissions, particularly from diffuse and dilute sources, pose a significant challenge for oxidation and valorization as existing methane oxidation routes rely on high temperatures or pressures. Researchers at MIT found that the catalytic coupling of alcohol oxidase with the iron-modified ZSM-5 (Fe-ZSM-5) zeolite catalyst, created a tandem methanotrophic system that partially oxidized methane at ambient temperatures and pressures. They showed that methane-to-formaldehyde selectivity could exceed 90% at room temperature. The generated formaldehyde was rapidly incorporated into a growing urea polymer. According to the researchers their work presents a sustainable route for methane oxidation… […]
Category Archives: Global warming
Oceans emit sulfur and cool the climate more than previously thought
Phys.org November 27, 2024 Ocean-emitted dimethyl sulfide (DMS) is a major source of climate-cooling aerosols. However, most of the marine biogenic sulfur cycling is not routed to DMS but to methanethiol (MeSH), another volatile whose reactivity has hitherto hampered measurements. An international team of researchers (Spain, Argentina, China, USA – Old Dominion University, France) compiled a database of seawater MeSH concentrations, identified their statistical predictors, and produced monthly fields of global marine MeSH emissions adding to DMS emissions. Implemented into a global chemistry-climate model, MeSH emissions increased the sulfate aerosol burden by 30 to 70% over the Southern Ocean and […]
Climate scientists argue that 1000-year sequestration strategies must be used to meet climate goals
Phys.org November 13, 2024 The scientifically recognized definition of Carbon Dioxide Removal requires removed atmospheric CO2 to be stored “durably”; however, it remains unclear what is meant by durably, and interpretations have varied from decades to millennia. An international team of researchers (Switzerland, USA – UC Berkeley) used a reduced-complexity climate model to examine the effect of Carbon Dioxide Removal with varying CO2 storage durations. They found that storage duration substantially affects whether net zero emissions achieve the desired temperature outcomes. With a typical 100-year storage duration, net zero CO2 emissions with 6 GtCO2 per year residual emissions would result […]
Scientists call for global action on microbial climate solutions
Phys.org November 11, 2024 By publishing concurrently across journals like an emergency bulletin, an international team of researchers (the Netherlands, Germany, UK, China, USA – Indiana University, University of North Carolina) not merely made a plea for awareness about climate change, instead, they demanded immediate, tangible steps that harness the power of microbiology and the expertise of researchers and policymakers to safeguard the planet for future generations. They proposed a multitude of microbe-based solutions, technologies that hold great promise and could be deployed along with other climate mitigation strategies. According to the team these solutions have not been deployed effectively […]
Measurements from ‘lost’ Seaglider offer new insights into Antarctic ice melting
Phys.org November 8, 2024 Solar-warmed surface waters subduct beneath Antarctica’s ice shelves because of wind forcing, but this process is poorly observed and its interannual variability is yet to be assessed. Researchers in the UK observed a 50-meter-thick intrusion of warm surface water immediately beneath the Ross Ice Shelf. Temperature in the uppermost 5 meters decreased toward the ice base in near-perfect agreement with an exponential fit, consistent with the loss of heat to the overlying ice. They found that Ekman forcing drove a heat transport into the cavity sufficient to contribute considerably to near-front melting; this transport increased over […]
MIT engineers make converting CO2 into useful products more practical
MIT News November 13, 2024 Electrochemical CO2 reduction has emerged as a promising CO2 utilization technology, with Gas Diffusion Electrodes becoming the predominant architecture to maximize performance. The electrodes must maintain robust hydrophobicity to prevent flooding, while also ensuring high conductivity to minimize ohmic losses. Researchers at MIT demonstrated a hierarchically conductive electrode architecture which overcame the scaling limitations by employing inter-woven microscale conductors within a hydrophobic expanded Polytetrafluoroethylene membrane. They developed a model which captured the spatial variability in voltage and product distribution on electrodes due to ohmic losses and used it to rationally design the hierarchical architecture which […]
Sliver of cool surface water helps the ocean absorb more carbon, study shows
Phys.org October 25, 2024 The ocean annually absorbs about a quarter of all anthropogenic carbon dioxide (CO2) emissions. Global estimates of air–sea CO2 fluxes are typically based on bulk measurements of CO2 in air and seawater and neglect the effects of vertical temperature gradients near the ocean surface. Theoretical and laboratory observations indicate that these gradients alter air–sea CO2 fluxes, because the air–sea CO2 concentration difference is highly temperature sensitive. However, in situ field evidence supporting their effect is so far lacking. An international team of researchers (UK, the Netherlands) presented independent direct air–sea CO2 fluxes alongside indirect bulk fluxes […]
Declines in plant resilience threaten carbon storage in the Arctic
Phys.org October 10, 2024 Rapid warming and increasing disturbances in high-latitude regions have caused extensive vegetation shifts and uncertainty in future carbon budgets. Better predictions of vegetation dynamics and functions require characterizing resilience, which indicates the capability of an ecosystem to recover from perturbations. A team of researchers in the US (The Ohio State University, University of Utah, Northern Arizona University) used temporal autocorrelation of remotely sensed greenness to quantify time-varying vegetation resilience during 2000–2019 across northwestern North American Arctic-boreal ecosystems. They found that vegetation resilience significantly decreased in southern boreal forests, including forests showing greening trends, while it increased […]
Loss of lake ice has wide-ranging environmental and societal consequences, analysis suggests
Phys.org October 10, 2024 Most of the world’s lakes freeze, with a median ice duration of 218 days. The rate of lake ice loss has markedly accelerated over the past 25 years, with ice melt in some regions across the Northern Hemisphere arriving 45 days per century earlier and with many lakes experiencing increased intermittency of ice cover during winter in addition to ice-free winters. Lake ice loss is expected to affect a substantial proportion of the world’s population. Until recently, both logistical challenges as well as misconceptions of winter as a time of quiescence resulted in limited winter research. […]
Study warns of ‘irreversible’ climate impacts from overshooting 1.5C
Phys.org October 9, 2024 An international team of researchers (Austria, Germany, France, UK, Switzerland, Australia, Norway) found that achieving declining global temperatures could limit long-term climate risks compared with a mere stabilization of global warming, including for sea-level rise and cryosphere changes. However, the possibility that global warming could be reversed many decades into the future might be of limited relevance for adaptation planning today. Temperature reversal could be undercut by strong Earth-system feedback resulting in high near-term and continuous long-term warming. To protect against high-risk outcomes, they identified the geophysical need for a preventive carbon dioxide removal capacity of […]