Absorbing It All
Building materials could store more than 16 billion tonnes of CO2 annually
Elisabeth Van Roijen, Sabbie Miller & Steven Davis
Science, 10 January 2025, Pages 176-182
Abstract:
Achieving net-zero greenhouse gas emissions likely entails not only lowering emissions but also deploying carbon dioxide (CO2) removal technologies. We explored the annual potential to store CO2 in building materials. We found that fully replacing conventional building materials with CO2-storing alternatives in new infrastructure could store as much as 16.6 ± 2.8 billion tonnes of CO2 each year -- roughly 50% of anthropogenic CO2 emissions in 2021. The total storage potential is far more sensitive to the scale of materials used than the quantity of carbon stored per unit mass of materials. Moreover, the carbon storage reservoir of building materials will grow in proportion to demand for such materials, which could reduce demand for more costly or environmentally risky geological, terrestrial, or ocean storage.
Transforming US agriculture for carbon removal with enhanced weathering
David Beerling et al.
Nature, 13 February 2025, Pages 425-434
Abstract:
Enhanced weathering (EW) with agriculture uses crushed silicate rocks to drive carbon dioxide removal (CDR). If widely adopted on farmlands, it could help achieve net-zero emissions by 2050. Here we show, with a detailed US state-specific carbon cycle analysis constrained by resource provision, that EW deployed on agricultural land could sequester 0.16–0.30 GtCO2 yr−1 by 2050, rising to 0.25–0.49 GtCO2 yr−1 by 2070. Geochemical assessment of rivers and oceans suggests effective transport of dissolved products from EW from soils, offering CDR on intergenerational timescales. Our analysis further indicates that EW may temporarily help lower ground-level ozone and concentrations of secondary aerosols in agricultural regions. Geospatially mapped CDR costs show heterogeneity across the USA, reflecting a combination of cropland distance from basalt source regions, timing of EW deployment and evolving CDR rates. CDR costs are highest in the first two decades before declining to about US$100–150 tCO2−1 by 2050, including for states that contribute most to total national CDR. Although EW cannot be a substitute for emission reductions, our assessment strengthens the case for EW as an overlooked practical innovation for helping the USA meet net-zero 2050 goals. Public awareness of EW and equity impacts of EW deployment across the USA require further exploration and we note that mobilizing an EW industry at the necessary scale could take decades.
Projections of multiple climate-related coastal hazards for the US Southeast Atlantic
Patrick Barnard et al.
Nature Climate Change, January 2025, Pages 101-109
Abstract:
Faced with accelerating sea level rise and changing ocean storm conditions, coastal communities require comprehensive assessments of climate-driven hazard impacts to inform adaptation measures. Previous studies have focused on flooding but rarely on other climate-related coastal hazards, such as subsidence, beach erosion and groundwater. Here, we project societal exposure to multiple hazards along the Southeast Atlantic coast of the United States. Assuming 1 m of sea level rise, more than 70% of the coastal residents and US$1 trillion in property are in areas projected to experience shallow and emerging groundwater, 15 times higher than daily flooding. Storms increase flooding exposure by an order of magnitude over daily flooding, which could impact up to ~50% of all coastal residents and US$770 billion in property value. The loss of up to ~80% of present-day beaches and high subsidence rates that currently affect over 1 million residents will exacerbate flooding and groundwater hazard risks.
Air pollution exposure in vitrified oocyte donors and male recipient partners in relation to fertilization and embryo quality
Sarah LaPointe et al.
Environment International, November 2024
Methods: Our study included 500 oocyte donors and 915 male recipient partners who contributed 1,095 oocyte thaw cycles (2008–2019). Daily ambient air pollutant exposure was estimated using spatio-temporal models based on residential address and averaged over folliculogenesis (i.e., three months prior to initiation of controlled ovarian stimulation), controlled ovarian stimulation, and spermatogenesis (i.e., 72 days prior to oocyte thaw). We used multivariable generalized estimating equations to estimate the adjusted odds ratios (aOR) and 95 % confidence intervals (CI) for an interquartile range increase in pollutant exposure in relation to the proportion of oocytes surviving thaw, oocytes fertilized, and usable embryos.
Results: Oocyte donors with higher exposure to organic carbon (OC) (aOR = 0.86 95 %CI 0.79,0.94) and particulate matter < 10 µm (aOR = 0.69 95 %CI 0.54,0.90) during folliculogenesis had a lower proportion of oocytes surviving thaw. During ovarian stimulation, higher particulate matter < 2.5 µm (aOR = 0.78 95 %CI 0.66, 0.91), nitrate (aOR = 0.83 95 % CI 0.69,0.99), and OC (aOR = 0.86 95 % CI 0.80,0.93) exposure was associated with a lower proportion of surviving oocytes while nitrogen dioxide (aOR = 1.11 95 %CI 1.00,1.23) and ozone (aOR = 1.19 95 %CI 1.04,1.37) exposure was associated with a higher proportion of fertilized oocytes and usable embryos. Elemental carbon (aOR = 0.93 95 %CI 0.87,1.00) and OC (aOR = 0.95 95 %CI 0.90,1.00) exposure during spermatogenesis was associated with a slightly lower proportion of usable embryos. On the day of oocyte thaw, higher ambient OC at the IVF clinic was associated with lower oocyte survival and higher ozone was associated with lower fertilization.
The Hidden Toll of Airborne Lead: Infant Mortality Impacts of Industrial Lead Pollution
Karen Clay, Edson Severnini & Xiao Wang
NBER Working Paper, February 2025
Abstract:
This paper uses U.S. Toxic Release Inventory data on air lead emissions to provide IV estimates of the effects of air lead concentration on infant mortality. The causal effect of lead on infant mortality is identified by annual variation in air fugitive lead emissions interacted with wind speed near reporting plants, which together determine local ambient lead concentration. Unlike stack emissions, which occur routinely and may prompt avoidance behavior, fugitive emissions are intermittent and influenced by both historical and current factors, such as wind speed variation, making them difficult to avoid. The paper has two main findings. First, higher air lead concentration causes higher infant mortality in the first month and in the first year, suggesting that both in utero and environmental exposures matter. Second, higher lead concentration increases deaths from low birthweight, sudden unexplained infant death (SUID), and respiratory and nervous system causes, which is consistent with findings from animal studies, even when accounting for behavioral responses. Back of the envelope calculations indicate that declines in fugitive lead emissions prevented 34-59 infant deaths per year, generating benefits of $380-$670 million annually in 2023 dollars.
Methane emissions from the Nord Stream subsea pipeline leaks
Stephen Harris et al.
Nature, 30 January 2025, Pages 1124-1130
Abstract:
The amount of methane released to the atmosphere from the Nord Stream subsea pipeline leaks remains uncertain, as reflected in a wide range of estimates. A lack of information regarding the temporal variation in atmospheric emissions has made it challenging to reconcile pipeline volumetric (bottom-up) estimates with measurement-based (top-down) estimates. Here we simulate pipeline rupture emission rates and integrate these with methane dissolution and sea-surface outgassing estimates to model the evolution of atmospheric emissions from the leaks. We verify our modelled atmospheric emissions by comparing them with top-down point-in-time emission-rate estimates and cumulative emission estimates derived from airborne, satellite and tall tower data. We obtain consistency between our modelled atmospheric emissions and top-down estimates and find that 465 ± 20 thousand metric tons of methane were emitted to the atmosphere. Although, to our knowledge, this represents the largest recorded amount of methane released from a single transient event, it is equivalent to 0.1% of anthropogenic methane emissions for 2022. The impact of the leaks on the global atmospheric methane budget brings into focus the numerous other anthropogenic methane sources that require mitigation globally. Our analysis demonstrates that diverse, complementary measurement approaches are needed to quantify methane emissions in support of the Global Methane Pledge.
High-Speed Rail and China's Electric Vehicle Adoption Miracle
Hanming Fang et al.
NBER Working Paper, February 2025
Abstract:
Using China's expansion of the high-speed rail system (HSR) as a quasi-natural experiment, we analyze the comprehensive vehicle registration data from 2010 to 2023 to estimate the causal impact of HSR connectivity on the adoption of electric vehicles (EVs). Implementing several identification strategies, including staggered difference-in-differences (DID), Callaway and Sant'Anna (CS) DID, and two instrumental-variable approaches, we consistently find that, by alleviating range anxiety, the expansion of HSR can account for up to one third of the increase in EV market share and EV sales in China during our sample period, with effects particularly pronounced in cities served by faster HSR lines. The results remain robust when controlling for local industrial policies, charging infrastructure growth, supply-side factors, and economic development. We also find that HSR connectivity amplifies the effectiveness of charging infrastructure and consumer purchase subsidies in promoting EV adoption.
The effect of CO2 ramping rate on the transient weakening of the Atlantic Meridional Overturning Circulation
Camille Hankel
Proceedings of the National Academy of Sciences, 7 January 2025
Abstract:
The Atlantic Meridional Overturning Circulation (AMOC) is a key component of the global climate that is projected to weaken under future anthropogenic climate change. While many studies have investigated the AMOC’s response to different levels and types of forcing in climate models, relatively little attention has been paid to the AMOC’s sensitivity to the rate of forcing change, despite it also being highly uncertain in future emissions scenarios. In this study, I isolate the AMOC’s response to different rates of CO2 increase in a state-of-the-art global climate model and find that the AMOC undergoes more severe weakening under faster rates of CO2 change, even when the magnitude of CO2 change is the same. I then propose an AMOC-ocean heat transport-sea ice feedback that enhances the decline of the circulation and explains the dependence on the rate of forcing change. The AMOC’s rate-sensitive behavior leads to qualitatively different climates (including differing Arctic sea ice evolution) at the same CO2 concentration, highlighting how the rate of forcing change is itself a key driver of global climatic change.
Global increase in the occurrence and impact of multiyear droughts
Liangzhi Chen et al.
Science, 17 January 2025, Pages 278-284
Abstract:
Persistent multiyear drought (MYD) events pose a growing threat to nature and humans in a changing climate. We identified and inventoried global MYDs by detecting spatiotemporally contiguous climatic anomalies, showing that MYDs have become drier, hotter, and led to increasingly diminished vegetation greenness. The global terrestrial land affected by MYDs has increased at a rate of 49,279 ± 14,771 square kilometers per year from 1980 to 2018. Temperate grasslands have exhibited the greatest declines in vegetation greenness during MYDs, whereas boreal and tropical forests have had comparably minor responses. With MYDs becoming more common, this global quantitative inventory of the occurrence, severity, trend, and impact of MYDs provides an important benchmark for facilitating more effective and collaborative preparedness toward mitigation of and adaptation to such extreme events.
Does Unilateral Decarbonization Pay For Itself?
Adrien Bilal & Diego Känzig
NBER Working Paper, January 2025
Abstract:
This paper shows that unilateral decarbonization pays for itself in large economies. We estimate economic damages from global temperature shocks and combine them with a climate-economy model to construct Domestic Costs of Carbon: $226 per ton for the United States and $216 per ton for the European Union. When compared to marginal abatement costs, these values imply over 80% unilateral decarbonization for both economies, an order of magnitude larger than under conventional damages estimated based on local temperature.