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Every year, trade winds over the Sahara Desert sweep up huge plumes of mineral dust, transporting hundreds of teragrams — enough to fill 10 million dump trucks — across North Africa and over the Atlantic Ocean. This dust can be blown for thousands of kilometers and settle in places as far away as Florida and the Bahamas.

The Sahara is the largest source of windblown dust to the Earth’s atmosphere. But researchers from MIT, Yale University, and elsewhere now report that the African plume was far less dusty between 5,000 and 11,000 years ago, containing only half the amount of dust that is transported today.

With rapid industrialization and urbanization over the past decades, China has experienced widespread air pollution induced by fine particulate matter with a diameter of 2.5 µm or less (PM2.5). To protect human health and meet the newly implemented annual PM2.5 target (less than 35 µg m-3), great efforts are needed to reduce emissions effectively. It is, therefore, essential to understand how future PM2.5 concentrations are affected by changes in anthropogenic emissions. 

A new multi-institutional study of the so-called global warming “hiatus” phenomenon — the possible temporary slowdown of the global mean surface temperature (GMST) trend said to have occurred from 1998 to 2013 — concludes the hiatus simply represents a redistribution of energy within the Earth system, which includes the land, atmosphere and the ocean.

In a paper published today in Earth’s Future, a journal of the American Geophysical Union, lead author Xiao-Hai Yan of the University of Delaware, along with leading scientists from the National Oceanic and Atmospheric Administration (NOAA), National Center for Atmospheric Research (NCAR), National Aeronautics and Space Administration (NASA), Scripps Institution of Oceanography, and University of Washington, discuss new understandings of the global warming “hiatus” phenomenon.

The environmental impact of your Thanksgiving dinner depends on where the meal is prepared.

Carnegie Mellon University researchers calculated the carbon footprint of a typical Thanksgiving feast – roasted turkey stuffed with sausage and apples, green bean casserole and pumpkin pie – for each state. The team based their calculations on the way the meal is cooked (gas versus electric range), the specific state’s predominant power source and how the food is produced in each area.

They found that dinners cooked in Maine and Vermont, states that rely mostly on renewable energy, emit the lowest amounts of carbon dioxide, a greenhouse gas that is tied to climate change. States that use coal power, such as Wyoming, West Virginia and Kentucky, have the highest carbon dioxide emissions.

La fabricación de cemento es uno de los procesos industriales más intensos en cuanto a huella de carbono, pero un equipo internacional de investigadores ha encontrado que con el tiempo, el material de construcción ampliamente utilizado reabsorbe gran parte del CO2 emitido cuando se fabricó.