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Mass tree die-offs are sparking worries of fire in California’s Sierra Nevada range. An outbreak of bark beetles, along with persistent drought in the state, have caused many evergreen trees to wither and die.

The damage spread rapidly through the mountains in the fall of 2015 after favorable spring conditions (warm and dry) led to a surge in beetle populations, according to Zach Tane, a remote sensing analyst with the U.S. Forest Service (USFS). The beetles burrow under a tree’s bark and lay their eggs. Once they penetrate the tree’s armor (the bark), they begin to gnaw into its living tissue, the phloem.

“Needles don’t turn red the next day. It’s a slow process of the tree dying, and it has to do with life cycle of bark beetle and how long needles can persist in a green state,” said Tane. “As the population of beetles grows, they can overwhelm the natural defenses of a tree. There’s a tipping point—that’s what happened in Colorado and probably what’s happening here.”

Un nuevo estudio ha descubierto por primera vez que el calentamiento del océano es la causa principal de retroceso de los glaciares en la Península Antártica. La península es uno de los mayores contribuyentes actuales a la elevación del nivel del mar y este nuevo hallazgo permitirá a los investigadores el hacer mejores predicciones de pérdida de hielo de esta región.

In this scary time of global species extinctions and loss of biodiversity below “safe” levels, The Field Museum recently announced some good news: Luzon Island, an island the size of the Indiana in the Philippines, holds the greatest concentration of mammals. The pressing question now is will we be able to protect this rich biodiversity in time?

This summer, with sea ice across the Arctic Ocean shrinking to below-average levels, a NASA airborne survey of polar ice just completed its first flights. Its target: aquamarine pools of melt water on the ice surface that may be accelerating the overall sea ice retreat.

NASA's Operation IceBridge completed the first research flight of its new 2016 Arctic summer campaign on July 13. The science flights, which continue through July 25, are collecting data on sea ice in a year following a record-warm winter in the Arctic.

The summer flights will map the extent, frequency and depth of melt ponds, the pools of melt water that form on sea ice during spring and summer. Recent studies have found that the formation of melt ponds early in the summer is a good predictor of the sea ice yearly minimum extent in September: if there are more ponds on the ice earlier in the melt season, they reduce the ability of sea ice to reflect solar radiation, which leads to more melt.

Un equipo internacional de científicos ha encontrado una forma potencialmente viable para eliminar las emisiones de dióxido de carbono antropogénico (causado o influenciado por los seres humanos) de la atmósfera: convertirlo en roca.El estudio, publicado en la revista Science, ha demostrado por primera vez que el dióxido de carbono, gas de efecto invernadero (CO2), puede ser permanente y rápidamente llevado lejos de la atmósfera, mediante su inyección en la roca volcánica.