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La reciente tendencia de aumento en la extensión del hielo marino en la Antártida, aparentemente en contradicción con las proyecciones del modelo climático, en gran medida se explica por una fluctuación natural del clima, según un nuevo estudio dirigido por el Centro Nacional de Investigación Atmosférica (NCAR).

Air pollutants interact with and break down plant-emitted scent molecules, which insect pollinators use to locate needed food, according to a team of researchers led by Penn State. The pollution-modified plant odors can confuse bees and, as a result, bees' foraging time increases and pollination efficiency decreases. This happens because the chemical interactions decrease both the scent molecules' life spans and the distances they travel.

While foraging for food, insects detect floral scent molecules in the air. Wind currents can carry these molecules up to thousands of feet from their original source to where bees have their hives.

"Many insects have nests that are up to 3,000 feet away from their food source, which means that scents need to travel long distances before insects can detect them," said Jose D. Fuentes, professor of meteorology and atmospheric science, Penn State. "Each insect has a detection threshold for certain kinds of scents and they find food by moving from areas of low concentrations of scents to areas of high concentrations."

Esos parches de color naranja en la foto no son precursores de invierno. Son árboles muertos o que se están muriendo en California, muy probablemente resultado de los daños forestales por el escarabajo del pino.

Forest fires in Indonesia last year released 11.3 million tonnes of carbon per day, researchers have found. This figure exceeds the daily rate of 8.9 million tonnes of carbon emissions from the whole of the European Union, the study says.

The 2015 fires were the worst since 1997, when a strong El Niño also fanned widespread fires, says the study, published in the journal Scientific Reports.

Fire is widely used in South-East Asia to clear vegetation and maintain land for the growing of crops, the paper explains. Last year, fires were exacerbated by extended drought associated with El Niño, releasing 857 million tonnes of carbon dioxide from September to October 2015, the authors say. This represents 97 per cent of the country’s annual carbon emissions.

Rising carbon dioxide emissions have caused the world’s oceans to become 30 percent more acidic since the Industrial Revolution, affecting everything from marine life’s ability to build shells to the pH level of fishes’ blood. Now, scientists have discovered that more acidic water also prevents mussels from attaching to rocks and other surfaces, which could have ramifications on the global food chain, the economy, and ecosystem health.