Adam Marblestone, un biofisico che lavora per Google DeepMind, ha cominciato a scrivere una serie di post su come utilizzare la tecnologia per influenzare il cambiamento climatico in atto.

Nel primo articolo Marblestone ammette di essere uno scienziato senza competenze specifiche di climatologia e che per questo ha voluto studiarne le basi per poter rispondere a domande come:

• How can I estimate the world’s remaining carbon budget for various levels of warming?

• What are the uncertainties in this?

• What would happen if Greenland melted?

• What are the fundamental physical limits on, say, the potential for sucking carbon dioxide out of the atmosphere? How low could the cost theoretically go?

• How many trees would you need to plant, and are you going to run out of water, land or fertilizer for them?

• If we did manage to remove a given amount of CO2, how would the climate respond? How would the climate respond if we magically ceased all emissions today?

• What would be the real impact if we could electrify all cars?

• Are batteries going to be able to store all the variable renewable energy we’ll need? Is there enough Uranium obtainable to power the world with nuclear? Order of magnitude, how much would it cost to just replace our entire energy supply with nuclear?

• Notwithstanding the complexity of their governance and potential moral hazard implications, do we have a solid science and engineering basis to believe that any geoengineering methods could theoretically work to controllably lower temperature, and if so, would that be able to slow down sea ice melt, too? Would it damage the ozone layer? How fast could you turn it off? Could it be done locally?

Per poter rispondere a queste domande l’autore, usando dati da centinaia di fonti diverse, comincia a fare calcoli dapprima molto a spanne e via via più raffinati, per capire come la quantità di CO2 immessa nell’atmosfera sta modificando il clima terrestre.

L’autore considera inoltre l’impatto dei feedback (positivi e negativi, a breve e lungo termine) che possono modificare sostanzialmente le previsioni sul cambiamento climatico, così come l’impatto sull’innalzamento del livello del mare o il possibile raggiungimento di punti critici (scioglimento del permafrost, scioglimento dei ghiacci in Antartide e Gronelandia) che potrebbero instaurare una reazione a catena che peggiorerebbe di molto la situazione.

L’articolo si conclude menzionando brevemente di cosa parleranno i post successivi e stilando alcune conclusioni su cosa si dovrebbe fare, tratte considerando non solo il clima ma anche alcuni aspetti economici e politici:

• Make sure our ability to measure and model everything in the climate system continues to improve, including for complex land and ocean biological effects.Lobby for a revenue-neutral, staged price on carbon, in rich countries initially — rich countries can bring down the cost for poor countries by developing and scaling up better, cheaper technology.
  In the USA there is a specific program with some high-profile advocates called the Carbon Dividends Plan. I certainly don’t want to say that a carbon tax is the only necessary policy though — also advanced R&D, tax credits, subsidies, lobbying reform, and down the line hopefully new social technology for making societal decisions would come into play.Economically incentivize a full transition to net-negative emissions by around 2050. This includes deploying a portfolio of existing clean technologies now to limit our cumulative carbon emissions and peak CO2 concentration.

  Heavily invest in large-scale, advanced R&D to bring down the cost of grid-scale energy storage, next-generation nuclear, novel clean manufacturing processes for things like steel and cement, improved agricultural technologies, smart grid-integrated buildings, and synthetic meat (among other areas). With enough technological innovation, I hope that the cost to decarbonize could be brought lower than the estimates of those like Nordhaus.

  Heavily invest in sustainable land use management and conservation, as well as aggressive afforestation.

  Switch to electric cars. (This will impact multiple key areas.)

  Bootstrap the nascent fields of direct air carbon capture / carbon sequestration, both chemical and biological, to the point where they can really scale cost-effectively, and seriously consider ocean liming, sequestration of agricultural waste biomass, and so forth (also next post). This involves both new research and the creation of new markets for carbon. Use sequestered carbon to make the jet fuel.

• Do the fundamental R&D on emergency adaptation strategies like solar radiation management and buttressing of glaciers.

Immagine da Wikimedia.