"Today we’re taking another big step by making the biggest corporate purchase of renewable energy in history. This purchase is made up of a 1,600-megawatt (MW) package of agreements and includes 18 new energy deals. Together, these deals will increase our worldwide portfolio of wind and solar agreements by more than 40 percent, to 5,500 MW—equivalent to the capacity of a million solar rooftops. Once all these projects come online, our carbon-free energy portfolio will produce more electricity than places like Washington D.C. or entire countries like Lithuania or Uruguay use each year.
Our latest agreements will also spur the construction of more than $2 billion in new energy infrastructure, including millions of solar panels and hundreds of wind turbines spread across three continents. In all, our renewable energy fleet now stands at 52 projects, driving more than $7 billion in new construction and thousands of related jobs.
To ensure maximum impact, all of our latest deals meet the rigorous “additionality” criteria we set out long ago for our energy purchases. This means we’re not buying power from existing wind and solar farms but instead are making long-term purchase commitments that result in the development of new projects."
Clockwise from top left: Wind and solar projects that currently serve Google in Sweden; North Carolina; the Netherlands; Oklahoma; and Chile.
Satellite data show increasing leaf area of vegetation due to direct factors (human land-use management) and indirect factors (such as climate change, CO2 fertilization, nitrogen deposition and recovery from natural disturbances). Among these, climate change and CO2 fertilization effects seem to be the dominant drivers. However, recent satellite data (2000–2017) reveal a greening pattern that is strikingly prominent in China and India and overlaps with croplands world-wide. China alone accounts for 25% of the global net increase in leaf area with only 6.6% of global vegetated area. The greening in China is from forests (42%) and croplands (32%), but in India is mostly from croplands (82%) with minor contribution from forests (4.4%). China is engineering ambitious programmes to conserve and expand forests with the goal of mitigating land degradation, air pollution and climate change. Food production in China and India has increased by over 35% since 2000 mostly owing to an increase in harvested area through multiple cropping facilitated by fertilizer use and surface- and/or groundwater irrigation. Our results indicate that the direct factor is a key driver of the ‘Greening Earth’, accounting for over a third, and probably more, of the observed net increase in green leaf area. They highlight the need for a realistic representation of human land-use practices in Earth system models.
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Making cement–the mineral compound that constitutes the most crucial ingredient of concrete–is an extremely carbon-intensive process. It’s produced in factories with massive kilns where raw materials, like limestone, clay, and shale, are heated to temperatures up to 1550 degrees Celsius, then ground into a powder. Heating the cement minerals to such high temperatures poses a sustainability concern, says Kemal Celik, professor of civil engineering at New York University in Abu Dhabi and the director of the Advanced Materials and Building Efficiency Research (AMBER) Laboratory. Producing cement accounts for around 7% of global CO2 emissions.
This fact, Celik says, got him interested in finding a better way to make the material. He and his team already knew that magnesium oxide, a mineral found in salt deposits like lakes and salt flats, could be converted into a type of cement. In the United Arab Emirates, where Celik and his team work, they realized they could tap the over 70 operating desalination plants for access to brine left over from the process of purifying seawater, which would otherwise just be dumped back into the Gulf. Synthesizing the magnesium oxide in brine into a cement-like substance requires much less heat than making ordinary cement. And, Celik says, as magnesium oxide cement hardens over its lifetime, it absorbs carbon dioxide over time to gain strength, potentially making it a carbon-negative building material.
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