hemisphere

The warm 1930s and heat extremes. (a) Season average MJJA mean surface air temperature anomalies (°C) relative to 1901–1930 over the continental U.S. (black line) and the Great Plains (red line) using the BEST observations. Gray shading denotes the Dust Bowl years between 1932 and 1939, and horizontal lines indicate the maximum MJJA value during that period (occurring in 1936) for both U.S. (dashed black line) and Great Plains (dashed red line); (b)…

The oceans absorb more than 90 percent of all extra heat trapped by the emissions we've produced by burning fossil fuels.This heat is enormous. It's as if we exploded an atom bomb underwater, every second of every day.The ocean isn't warming at the same rate everywhere. We know the heat is concentrated in the fast, narrow currents that flow along the east coasts of the world's continents and funnel warm water from the tropics down towards the poles.In the Southern Hemisphere, these currents – known as the western…

January 2020: Dense plumes of smoke from the Australian forest fires drifted through the otherwise very clean atmosphere over Punta Arenas. Seen here in the lidar measurements as a green-yellow layer at an altitude of 20 to 25km. Credit: Cristofer Jimenez, TROPOS The 2019/20 wildfires in Australia transported more smoke into the atmosphere than observed ever before anywhere in the world. In the so-called Black Summer, three…

False-color view of total ozone over the Arctic pole during the beginning of 2020. The purple and blue colors are where there is the least ozone, and the yellows and reds are where there is more ozone. Credit: NASA Ozone WatchMany people are aware of the hole in the ozone layer over Antarctica, but what is less widely known is that the protective ozone in the stratosphere over the Arctic is periodically destroyed as well, thinning the ozone layer there. This last happened in the spring of 2020, and before that, in the…

Through June, sky watchers have had the pleasure of watching all five of the planets that we can see with the naked eye – Mercury, Venus, Mars, Jupiter, Saturn – line up in the sky. And this weekend, the crescent Moon will join them.   Impressively, the planets currently appear in order of their distance from the Sun, from left to right as you scan the horizon: that means starting with Mercury (an average of 58 million kilometers or 36 million miles from the Sun) and ending with Saturn (an average of 1.4 billion…

Freezing rain at Mountain Heng. Credit: Li Xingyu Freezing rain is a typical weather disaster in winter and early spring over many regions of the world, even tropical areas. It develops as supercooled water (below 0 °C) in the air and freezes immediately after depositing on cold surfaces. In southern China, freezing rain mainly happens in the mountainous areas.…