Category Archives: Scientific American

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Mexico Is Poised for Energy Boom

Mexico reopened its energy market to outside producers in August for the first time in more than 75 years. Until now, private companies could only serve as contractors to the national hydrocarbon or electricity monopolies.

Mexicans formerly took pride in keeping a major natural resource in national hands. Pemex, the state petroleum monopoly, provided almost a third of federal revenues. Yet Pemex’s production began dropping in the mid-1990s. In 2013, the U.S. Energy Information Administration (EIA) predicted (PDF) that by 2025 Mexican oil production would plunge by more than 50 percent from 2010 levels, despite the presence of the equivalent of 450 billion barrels of oil in Mexico, on par with Saudi Arabia’s resources. On August 25, citing the reforms, the EIA predicted a turnaround in the decline over the next few years and a return to growth by 2025. Mexico is now on the verge of an oil and gas boom. Continue reading

Hitting Rock Bottom

Fishing boats have dragged nets across the seafloor in pursuit of bottom-feeding fish and crustaceans since the Middle Ages. In recent decades, motorized fishing fleets, powered by government subsidies, have taken heavier nets deeper and farther offshore. The annual haul from international waters in 2010 was reported to be worth more than $600 million.

To see how bottom trawling is changing the ocean’s bottom, ecologist Antonio Pusceddu of the Marche Polytechnic University in Ancona, Italy, and his team took seafloor sediment samples at trawled and untouched sites off Spain’s northeastern coast between 500 and 2,000 meters below the surface. They then counted the number of individuals and species in those samples and measured the amount of carbon in the sediment. Continue reading

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Health Benefits of Bike Sharing Depend on Age, Gender

In the middle of the evening rush hour last November 29 more than 1,000 London cyclists staged a “die-in” to protest the traffic deaths of fellow riders and to demand more investment in bike-friendly roads. London’s streets may have grown friendlier to cyclists since the 2010 introduction of its Barclays Cycle Hire bike-sharing system but according to those at the protest, London is still too dangerous. The hundreds of cities that have launched bicycle-sharing systems in the last decade offer similar reasons for doing it: Bicycling reduces car traffic and pollution in city centers and is healthy exercise. But although all road-users benefit from less-crowded streets, a recent study suggests that the health benefits of bike-sharing programs depend on who is doing the riding.London’s bike-sharing program had registered 191,702 users at last count. Public health researcher James Woodcock at the University of Cambridge in England and his colleagues imagined, and calculated, how those riders lives might have been different had they not used the bikes. They examined data from 2.1 million hours of use between April 2011 and March 2012 and compared the health impact of those 2.1 million hours with the alternatives: more walking, public transit use or driving. To their surprise, the team reports in the February 13 BMJ (British Medical Journal), the switch to cycling may not have been helpful for young women. The health benefits also seem to differ by age, with older riders of both genders gaining more benefits than younger ones.

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Train of Thought Derailed: How an Accident Can Affect Your Brain

My cousin Guillermo Cassinello Toscano was on the train that derailed in Santiago de Compostela, Spain, last week when it went around a bend at twice the speed limit. Cassinello heard a loud vibration and then a powerful bump and then found himself surrounded by bloody bodies in wagon number nine. Shaking, he escaped the wreckage through either a door or a hole in the train—he cannot recall—then sat amid the smoke and debris next to the track and began to cry. Seventy-nine passengers died. Continue reading