This video is in partnership with Bill and Melinda Gates. You can check out the Gates Annual Letter here: https://b-gat.es/2GxIwba Concrete is responsible for 8% of humanity’s carbon emissions because making its key ingredient - cement - chemically releases CO2, and because we burn fossil fuels to make it happen. Thanks to our Patreon patrons https://www.patreon.com/MinuteEarth and our YouTube members. ___________________________________________ To learn more, start your googling with these keywords: Portland cement - the most common type of cement used worldwide, made with limestone Limestone - a hard sedimentary rock, composed mainly of calcium carbonate (which is also in shells & eggs) Cement - a powder used in construction that’s made by grinding clinker with other minerals and mixing with water to form a paste that sticks to sand, gravel or crushed stone to make concrete Concrete - a building material made by mixing cement with water to form a paste that gains body through fillers like sand and gravel Clinker - an intermediate marble-sized product in cement production created by sintering limestone with clay and other things Sinter - to turn a powdery solid into a single mass by heating it without liquefaction Mortar - another building material (used to adhere bricks or stones together) made by mixing cement with water and sand Calcination - the process of heating a substance to a high temperature, but below its melting point, so it thermally decomposes (like limestone into lime & CO2) Process emissions - the name for the CO2 that comes from limestone when it thermally decomposes ___________________________________________ Subscribe to MinuteEarth on YouTube: Support us on Patreon: And visit our website: https://www.minuteearth.com/ Say hello on Facebook: http://goo.gl/FpAvo6 And Twitter: http://goo.gl/Y1aWVC And download our videos on itunes:  https://goo.gl/sfwS6n ___________________________________________ Credits (and Twitter handles): Script Writer & Narrator: Alex Reich (@alexhreich) Video Illustrator: Adam Thompson Video Director: David Goldenberg (@dgoldenberg) With Contributions From: Henry Reich, Kate Yoshida, Ever Salazar, Peter Reich, Arcadi Garcia Rius Music by: Nathaniel Schroeder: ___________________________________________ References: Andrew, R. M. 2018. Global CO2 emissions from cement production. Earth System Science Data, 10(1), 195. https://www.earth-syst-sci-data.net/10/195/2018/essd-10-195-2018.pdf Benhelal, E., et al. 2013. Global strategies and potentials to curb CO2 emissions in cement industry. Journal of cleaner production, 51, 142-161. http://www.academia.edu/download/39977040/1-s2.0-S0959652612006129-main.pdf Beyond Zero Emissions.  August 2017. Zero Carbon Industry Plan: Rethinking Cement. Available for download at http://bze.org.au Davis, S.J., et al. 2018. Net-zero emissions energy systems. Science, 360(6396), eaas9793. https://cloudfront.escholarship.org/dist/prd/content/qt16109441/qt16109441.pdf Lehne, J., & Preston., F. June 2018. Making Concrete Change: Innovation in Low-carbon Cement and Concrete. Chatham House Report. http://bit.ly/2Vlb3oC Timperley, J. September 13 2018. Q&A: Why cement emissions matter for climate change. https://www.carbonbrief.org/qa-why-cement-emissions-matter-for-climate-change World Bank. 2019. World Development Indicators: Urban population. https://data.worldbank.org/indicator/SP.URB.TOTL