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Cement, Steel, and Natural Gas Are Major Greenhouse Gas Emitters, Too

Taken together, cement production, iron- and steelmaking, and natural-gas leaks rival transportation in their effects on climate

2 min read
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While our June 2018 special report, “Blueprints for a Miracle,” covers many of the key sources of greenhouse gases and strategies for their mitigation, the report does not address three rather substantial sources. The production of cement—the primary component in concrete—accounts for about 5 percent of global carbon dioxide emissions. Iron- and steelmaking contributes a similar amount [PDF]. The use of natural gas (methane) in place of oil or coal reduces carbon emissions, but methane itself is a potent greenhouse gas, and a considerable quantity leaks into the atmosphere during its production and transport. Estimates suggest that such leaks are comparable in their climate effect to those of cement production or iron- and steelmaking. Here’s a quick take on what might be done to limit these three sources.

  • Cement Production

    imgIllustration: James Provost

    The Problem: Copious quantities of CO2 are emitted during the conversion of limestone (CaCO3) to lime (CaO), a key ingredient in cement. That conversion is done in a kiln [yellow], which is heated by burning fossil fuels, a process that emits still more CO2.

    Low-Tech Solution: Use less lime and replace it with fly ash, a by-product of burning coal. The ancient Romans did something similar, using volcanic ash in their pozzolana concrete, examples of which have lasted thousands of years.

    High-Tech Solution: Add liquefied CO2 captured from power plants to wet concrete, where it will form tiny crystals of calcium carbonate, effectively sequestering the carbon and keeping it out of the atmosphere indefinitely.

  • Iron- and Steelmaking

    imgIllustration: James Provost

    The Problem: Converting iron ore to iron—the principal component of steel—requires coal, which serves as a reducing agent and provides the necessary heat as it is burned in a blast furnace [yellow]. That combustion releases large amounts of CO2 into the atmosphere.

    Low-Tech Solution: The simplest way to reduce these emissions is to recycle more steel, thus diminishing the need to mine iron ore and convert it to iron. Steel is often recycled now, but even more could be reused.

    High-Tech Solution: If sufficient renewably sourced electricity is available, iron could be extracted from iron ore by electrolysis, thereby avoiding carbon emissions. Electrolysis is similarly used today at aluminum smelters.

  • Natural-Gas Leaks

    imgIllustration: James Provost

    The Problem: The infrastructure used in the production and transport of natural gas is prone to leaking if it is not properly maintained.

    Low-Tech Solution: The natural-gas industry could be more diligent in its routine checks for leaks in the equipment it uses, even in settings where such gas leaks don’t create a risk of explosion.

    High-Tech Solution: Laser-based systems can be used to monitor for leaks at a distance. One company pursuing this technology is LongPath Technologies, a spinoff from the University of Colorado, Boulder.

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AI Goes to K Street: ChatGPT Turns Lobbyist

Automated influence campaigns could spell trouble for society

3 min read
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Concerns around how professional lobbyists distort the political process are nothing new. But new evidence suggests their efforts could soon be turbocharged by increasingly powerful language AI. A proof of concept from a Stanford University researcher shows that the technology behind Internet sensation ChatGPT could help automate efforts to influence politicians.

Political lobbyists spend a lot of time scouring draft bills to assess if they’re pertinent to their clients’ objectives, and then drafting talking points for speeches, media campaigns, and letters to Congress designed to influence the direction of the legislation. Given recent breakthroughs in the ability of AI-powered services like ChatGPT to analyze and generate text, John Nay, a fellow at the Stanford Center for Legal Informatics, wanted to investigate whether these models could take over some of that work.

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Forecasting the Ice Loss of Greenland’s Glaciers With Viscoelastic Modeling

Researchers at the Alfred Wegener Institute in Germany are developing new models to simulate how glaciers behave

8 min read
Aerial view of Nioghalvfjerdsbræ showing the extensive patterns of the crevasses

This sponsored article is brought to you by COMSOL.

To someone standing near a glacier, it may seem as stable and permanent as anything on Earth can be. However, Earth’s great ice sheets are always moving and evolving. In recent decades, this ceaseless motion has accelerated. In fact, ice in polar regions is proving to be not just mobile, but alarmingly mortal.

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