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There’s good news from Antarctica, where researchers with tools like ozonesondes — pictured above — have been following the infamous ozone hole as it waxes and wanes over the seasons. The ozone hole has shrunk by 1.5 million square miles – around 4 million square kilometers — and this “healing” trend appears to be continuing.

A major ecological catastrophe has been averted, and we can cite human intervention as the reason. When the globe swept into action with 1987′s Montreal Protocol, which banned a number of substances known to contribute to ozone depletion, it apparently worked.

When scientists first began to observe a hole in the ozone layer over Antarctica, it was a cause for grave concern. Though ozone levels actually fluctuate throughout the year, they perform an important function by blocking the sun’s harmful UV radiation.

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.

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.