Creative Energy
Presenting balanced geoengineering information has little effect on mitigation engagement
Christine Merk & Gernot Wagner
Climatic Change, January 2024
Abstract:
“Moral hazard” links geoengineering to mitigation via the fear that either solar geoengineering (solar radiation management, SRM) or carbon dioxide removal (CDR) might crowd out the desire to cut emissions. Fear of this crowding-out effect ranks among the most frequently cited risks of (solar) geoengineering. We here test moral hazard versus its inverse in a large-scale, revealed-preference experiment (n ~ 340,000) on Facebook and find little to no support for either outcome. For the most part, talking about SRM or CDR does not motivate our study population to support a large US environmental non-profit’s mission, nor does it turn them off relative to baseline climate messaging, except when using extreme messengers and framings. Our results indicate the importance of actors and reasoned narratives of (solar) geoengineering to help guide public discourse.
---------------------
Addressing climate change with behavioral science: A global intervention tournament in 63 countries
Madalina Vlasceanu et al.
Science Advances, February 2024
Abstract:
Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions’ effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior -- several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people’s initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors.
---------------------
A representative survey experiment of motivated climate change denial
Lasse Stoetzer & Florian Zimmermann
Nature Climate Change, February 2024, Pages 198–204
Abstract:
Climate change is arguably one of the greatest challenges today. Although the scientific consensus is that human activities caused climate change, a substantial part of the population downplays or denies human responsibility. In this registered report, we present causal evidence on a potential explanation for this discrepancy: motivated reasoning. We conducted a tailored survey experiment on a broadly representative sample of 4,000 US adults to provide causal evidence on how motivated cognition shapes beliefs about climate change and influences the demand for slanted information. We further explore the role of motives on environmentally harmful behaviour. Contrary to our hypotheses, we find no evidence that motivated cognition can help to explain widespread climate change denial and environmentally harmful behaviour.
---------------------
Climate Policy Reform Options in 2025
John Bistline et al.
NBER Working Paper, February 2024
Abstract:
With the expiration of many tax cuts and unmet climate targets, 2025 could be a crucial year for climate policy in the United States. Using an integrated model of energy supply and demand, this paper aims to assess climate policies that the U.S. federal government may consider in 2025 and to evaluate emissions reductions, fiscal costs and revenues, and household energy expenditures across a range of policy scenarios. Model results suggest that the emissions reductions of the Inflation Reduction Act are significantly augmented under scenarios that add a modest carbon fee or, to a lesser extent, that implement a clean electricity standard in the power sector. Second, net fiscal costs can be substantially reduced in scenarios that include a carbon fee, especially if fossil fuel exports are taxed. Third, expanding the IRA tax credits yields modest additional emissions reductions with higher fiscal costs. Finally, although none of the policy combinations across these scenarios achieve the U.S. target of a 50-52% economy-wide emissions reduction by 2030 from 2005 levels, the carbon fee and clean electricity standard scenarios achieve these levels between 2030 and 2035.
---------------------
Power Flows: Transmission Lines and Corporate Profits
Catherine Hausman
NBER Working Paper, January 2024
Abstract:
Economists, energy experts, and policymakers have called for accelerating investment in the U.S. electricity transmission network. Additional transmission lines could better integrate markets, reducing the total cost of electricity generation. They could also allow for the better integration of renewable energy sources such as wind and solar, located in areas that traditionally did not have much generation capacity and that are far away from centers of demand. In this paper, I document the magnitude of static allocative inefficiencies induced by transmission congestion in two major U.S. electricity markets. I show that the allocative inefficiencies are rising over time, totaling more than $2 billion in 2022. Moreover, I document an important political economy dimension not yet explored in the literature: the magnitudes of gains and losses from this market integration at some individual firms is surprisingly large: four firms would have experienced a collective $1.6 billion drop in operating profits in 2022 had the market been integrated. I then tie some of these firms to reports of transmission hold-up in these markets. I argue that understanding firm-level gains and losses is just as important as understanding overall inefficiencies, particularly in an environment where incumbents may have the power to block new lines.
---------------------
Enhanced weathering in the US Corn Belt delivers carbon removal with agronomic benefits
David Beerling et al.
Proceedings of the National Academy of Sciences, 27 February 2024
Abstract:
Terrestrial enhanced weathering (EW) of silicate rocks, such as crushed basalt, on farmlands is a promising scalable atmospheric carbon dioxide removal (CDR) strategy that urgently requires performance assessment with commercial farming practices. We report findings from a large-scale replicated EW field trial across a typical maize-soybean rotation on an experimental farm in the heart of the United Sates Corn Belt over 4 y (2016 to 2020). We show an average combined loss of major cations (Ca2+ and Mg2+) from crushed basalt applied each fall over 4 y (50 t ha−1 y−1) gave a conservative time-integrated cumulative CDR potential of 10.5 ± 3.8 t CO2 ha−1. Maize and soybean yields increased significantly (P < 0.05) by 12 to 16% with EW following improved soil fertility, decreased soil acidification, and upregulation of root nutrient transport genes. Yield enhancements with EW were achieved with significantly (P < 0.05) increased key micro- and macronutrient concentrations (including potassium, magnesium, manganese, phosphorus, and zinc), thus improving or maintaining crop nutritional status. We observed no significant increase in the content of trace metals in grains of maize or soybean or soil exchangeable pools relative to controls. Our findings suggest that widespread adoption of EW across farming sectors has the potential to contribute significantly to net-zero greenhouse gas emissions goals while simultaneously improving food and soil security.
---------------------
Temperature Extremes Impact Mortality and Morbidity Differently
Carlos Gould et al.
NBER Working Paper, March 2024
Abstract:
Increased temperature-related mortality is predicted to be one of the largest contributors to future economic damages from climate change globally, with declines in cold-related deaths in some regions outweighed by increases in heat-related deaths in others. Changes in temperature could also affect non-fatal health outcomes, whose aggregate societal burden is large, yet much less is known about how temperature affects the overall level and distribution of morbidity. Using georeferenced data on emergency department visits, mortality, and daily temperatures across California from 2006-2017, we show that the effect of temperature on mortality differs substantially from its effect on ED visits: mortality increases under extreme heat and cold, whereas ED visits increase under extreme heat but decline under extreme cold. These differential responses fundamentally shape the burden of future climate change: we predict that mortality in California will decrease by 0.32% due to changes in temperatures by mid-century, with declining cold deaths outweighing increasing heat deaths, but that ED visits will increase by 0.46% over the same period in the state, representing a total of 1.9 million excess visits. Our findings suggest that projected impacts of future warming on mortality, including benefits in many areas, might be a poor guide for morbidity impacts.
---------------------
Food without agriculture
Steven Davis et al.
Nature Sustainability, January 2024, Pages 90–95
Abstract:
Efforts to make food systems more sustainable have emphasized reducing adverse environmental impacts of agriculture. In contrast, chemical and biological processes that could produce food without agriculture have received comparatively little attention or resources. Although there is a possibility that someday a wide array of attractive foods could be produced chemosynthetically, here we show that dietary fats could be synthesized with <0.8 g CO2-eq kcal−1, which is much less than the >1.5 g CO2-eq kcal−1 now emitted to produce palm oil in Brazil or Indonesia. Although scaling up such synthesis could disrupt agricultural economies and depend on consumer acceptance, the enormous potential reductions in greenhouse gas emissions as well as in land and water use represent a realistic possibility for mitigating the environmental footprint of agriculture over the coming decade.
---------------------
Climate Change, Population Growth, and Population Pressure
Vernon Henderson et al.
NBER Working Paper, February 2024
Abstract:
We develop a novel method for assessing the effect of constraints imposed by spatially-fixed natural resources on aggregate economic output. We apply it to estimate and compare the projected effects of climate change and population growth over the course of the 21st century, by country and globally. We find that standard population growth projections imply larger reductions in income than even the most extreme widely-adopted climate change scenario (RCP8.5). Climate and population impacts are correlated across countries: climate change and population growth will have their most damaging effects in similar places. Relative to previous work on macro climate impacts, our approach has the advantages of being disciplined by a simple macro growth model that allows for adaptation and of assessing impacts via a large set of climate moments, not just annual average temperature and precipitation. Further, our estimated effects of climate are by construction independent of country-level factors such as institutions.
---------------------
Progressive unanchoring of Antarctic ice shelves since 1973
Bertie Miles & Robert Bingham
Nature, 22 February 2024, Pages 785–791
Abstract:
Mass loss of the Antarctic Ice Sheet has been driven primarily by the thinning of the floating ice shelves that fringe the ice sheet, reducing their buttressing potential and causing land ice to accelerate into the ocean. Observations of ice-shelf thickness change by satellite altimetry stretch back only to 1992 and previous information about thinning remains unquantified. However, extending the record of ice-shelf thickness change is possible by proxy, by measuring the change in area of the surface expression of pinning points -- local bathymetric highs on which ice shelves are anchored. Here we measure pinning-point change over three epochs spanning the periods 1973–1989, 1989–2000 and 2000−2022, and thus by proxy infer changes to ice-shelf thickness back to 1973–1989. We show that only small localized pockets of ice shelves were thinning between 1973 and 1989, located primarily in the Amundsen Sea Embayment and the Wilkes Land coastline. Ice-shelf thinning spreads rapidly into the 1990s and 2000s and is best characterized by the proportion of pinning points reducing in extent. Only 15% of pinning points reduced from 1973 to 1989, before increasing to 25% from 1989 to 2000 and 37% from 2000 to 2022. A continuation of this trend would further reduce the buttressing potential of ice shelves, enhancing ice discharge and accelerating the contribution of Antarctica to sea-level rise.
---------------------
300 years of sclerosponge thermometry shows global warming has exceeded 1.5 °C
Malcolm McCulloch et al.
Nature Climate Change, February 2024, Pages 171–177
Abstract:
Anthropogenic emissions drive global-scale warming yet the temperature increase relative to pre-industrial levels is uncertain. Using 300 years of ocean mixed-layer temperature records preserved in sclerosponge carbonate skeletons, we demonstrate that industrial-era warming began in the mid-1860s, more than 80 years earlier than instrumental sea surface temperature records. The Sr/Ca palaeothermometer was calibrated against ‘modern’ (post-1963) highly correlated (R2 = 0.91) instrumental records of global sea surface temperatures, with the pre-industrial defined by nearly constant (<±0.1 °C) temperatures from 1700 to the early 1860s. Increasing ocean and land-air temperatures overlap until the late twentieth century, when the land began warming at nearly twice the rate of the surface oceans. Hotter land temperatures, together with the earlier onset of industrial-era warming, indicate that global warming was already 1.7 ± 0.1 °C above pre-industrial levels by 2020. Our result is 0.5 °C higher than IPCC estimates, with 2 °C global warming projected by the late 2020s, nearly two decades earlier than expected.
---------------------
The growing inadequacy of an open-ended Saffir–Simpson hurricane wind scale in a warming world
Michael Wehner & James Kossin
Proceedings of the National Academy of Sciences, 13 February 2024
Abstract:
Global warming increases available sensible and latent heat energy, increasing the thermodynamic potential wind intensity of tropical cyclones (TCs). Supported by theory, observations, and modeling, this causes a shift in mean TC intensity, which tends to manifest most clearly at the greatest intensities. The Saffir–Simpson scale for categorizing damage based on the wind intensity of TCs was introduced in the early 1970s and remains the most commonly used metric for public communication of the level of wind hazard that a TC poses. Because the scale is open-ended and does not extend beyond category 5 (70 m/s windspeed or greater), the level of wind hazard conveyed by the scale remains constant regardless of how far the intensity extends beyond 70 m/s. This may be considered a weakness of the scale, particularly considering that the destructive potential of the wind increases exponentially. Here, we consider how this weakness becomes amplified in a warming world by elucidating the past and future increases of peak wind speeds in the most intense TCs. A simple extrapolation of the Saffir–Simpson scale is used to define a hypothetical category 6, and we describe the frequency of TCs, both past and projected under global warming, that would fall under this category. We find that a number of recent storms have already achieved this hypothetical category 6 intensity and based on multiple independent lines of evidence examining the highest simulated and potential peak wind speeds, more such storms are projected as the climate continues to warm.