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La mayoría de nosotros pensamos en el olor dulce después de una tormenta como el resultado de que la lluvia ha enjuagado el aire de contaminantes y polvo. Pero resulta que la lluvia también provoca la liberación de una nube de partículas del suelo húmedo al aire, un hallazgo con consecuencias propias sobre la forma cómo los científicos modelan el clima y el futuro de nuestro planeta.

Los coches híbridos han recorrido un largo camino desde que la primera Toyota Prius debutó en Japón hace casi 20 años. Lo mismo puede decirse de los coches eléctricos ya que GM lanzó su EV1 a finales de 1990, sólo para dar marcha atrás, los recuperó y los destruyó, enfureciendo de paso a sus aficionados en el proceso. En la actualidad hay decenas de modelos híbridos que disfrutaron de una subida en los precios de la gasolina y sus ventas se dispararon 2007…y nuevamente en 2012. Sin embargo, más recientemente, sus ventas globales han estado en declive. Mientras tanto los vehículos eléctricos son cada vez más sofisticados, están mejorando su alcance y han visto las ventas en repunte, mientras que los fabricantes de automóviles se han vuelto más competitivos en su publicidad.

The idea that the young Earth had a thicker atmosphere turns out to be wrong. New research from the University of Washington uses bubbles trapped in 2.7 billion-year-old rocks to show that air at that time exerted at most half the pressure of today’s atmosphere.

A recent study released by the National Aeronautics and Space Administration (NASA) concludes that the current drought that began in 1998 in the eastern Mediterranean Levant  – which includes Cyprus, Israel, Jordan, Lebanon, Palestine, Syria, and Turkey – is the region’s worst dry spell since 1100 C.E.

NASA scientists reconstructed our regional drought history by studying records of tree rings, from dead and live specimens, across several Mediterranean countries to determine patterns of dry and wet years over a 900-year time span. Tree rings are good indicators of precipitation since dry years cause thin rings while thick rings show when water was plentiful. They concluded that the years between 1998 and 2012 were drier than any other period, and that the drought was likely caused by humans.

Ben Cook, lead author and climate scientist at NASA’s Goddard Institute for Space Studies and the Lamont Doherty Earth Observatory at Columbia University in New York City, said the range of regional weather events has varied widely over the last millennium, but the past twenty years stand out as extreme, falling outside the range of natural variability.

 Air pollution legislation to control fossil fuel emissions and the associated acid rain has worked – perhaps leading to the need for sulfur fertilizers for crop production. A University of Illinois study drawing from over 20 years of data shows that sulfur levels in Midwest watersheds and rivers have steadily declined, so much so that farmers may need to consider applying sulfur in the not too distant future.

“We don’t think there are actual sulfur deficiencies yet, but clearly more sulfur is coming out of the soil and water than what is going in,” says U of I biogeochemist Mark David. “As the Clean Air Act and amendments have taken effect there has been a reduction in sulfur emissions from coal combustion, so that the amount of atmospheric sulfur deposited each year is only 25 percent of what it used to be. At some point, farmers are going to have to fertilize with sulfur.”