Environment

Road to Extinction

A new report by the group NatureServe says 34% of all plants and 40% of all animals in the US are at risk of extinction. Authors of the report say the warning is based on 50 years of extensive data collected by the nonprofit.

“Two-fifths of our ecosystems are in trouble,” said the Virginia-based group’s vice president for data and methods, Regan Smyth. “Freshwater invertebrates and many pollinators, the foundation of a healthy, functional planet, are in precipitous decline.” Most “imperiled” are all of the country’s tropical forests, tropical savannas and various grasslands.

Rainbow Clouds

The Arctic Circle is best known for its Northern Lights. But this emerald display was recently replaced by spectacular iridescent rainbows. Rare ‘rainbow clouds’ painted the skies over the Arctic Circle in Finland, Iceland and Norway at the end of January.

The phenomenon, caused by extreme freezing temperatures in the stratosphere. While auroras occur when solar wind collides with atoms in the Earth's atmosphere, rainbow-coloured ‘polar stratospheric clouds’ (PSCs) are caused by tiny atmospheric ice crystals. So-called ‘rainbow clouds’ are a result of cloud iridescence caused by small water droplets or ice crystals diffracting the sun’s light.

Beautiful as they are, rainbow clouds are bad news for the climate. The chemical reactions that they encourage break down the ozone layer, which shields Earth from the sun’s harmful UV rays.