Taxonomy term

News

New cloud types recognized

Familiar clouds like cumulonimbus, cirrocumulus and nimbostratus have some new company. The World Meteorological Organization (WMO) has published a new edition of its International Cloud Atlas, the first revision since 1987. The updated version — released in digital format for the first time — compiles recent observations and introduces about a dozen new terms, such as “asperitas,” which refers to a cloud whose sweeping undulations resemble the surface of a stormy sea, as well as names for clouds induced by wildfires and by human activity. There is even a new cloud species, “volutus,” which describes long, tube-shaped rolling clouds.

27 Jun 2017

Two ichthyosaurs become one

While dinosaurs ruled on land in the Mesozoic, dolphin-like marine reptiles called ichthyosaurs roamed the oceans. Paleontologists first described the genus in 1821 based on remains discovered in England, naming the first species Ichthyosaurus communis. The description of a second species, I. intermedius, followed in 1822. Although these two species were the earliest-known ichthyosaurs, they are also some of the most poorly understood, as their initial descriptions were based on limited remains.

22 Jun 2017

Platinum may point to impact theory for Younger Dryas

Some large meteorite strikes leave obvious craters on Earth’s surface, while others that hit water or ice or explode in the air may only leave subtle markers in the soil, such as exotic minerals or elevated levels of rare elements like platinum or iridium. In a new study, researchers report spikes of platinum in sediments at archaeological sites across North America, offering new evidence, they suggest, of a major meteorite strike about 12,800 years ago, just before the onset of a global cold period known as the Younger Dryas. The lack of a telltale crater dating to this time, however, has left scientists debating for years whether an impact actually occurred and what, if any, role it had in setting off the cold snap and affecting some of Earth’s human and animal populations.

21 Jun 2017

Rearranging the dinosaur family tree

Dinosaurs have long been grouped into two major clades — Ornithischia and Saurischia — largely based on the shapes of their hips. But new phylogenetic research is shaking up the dinosaur family tree, suggesting the traditional two-branch system needs reorganizing.

20 Jun 2017

Northeast and Midwest U.S. projected to warm faster than national average

The U.S. Northeast and Midwest will warm quickly in the coming decades compared to national and global averages, reaching established temperature benchmarks sooner than most of the rest of the country, and the world, according to recent research published in PLOS ONE.

16 Jun 2017

Whirling "gravel devils" show wind can carry more than just sand

Sand grains, by definition, are between 0.06 and 2 millimeters in diameter, and they are often thought of by scientists as the largest sediments that wind can transport, with larger sediments simply being too hefty for winds to keep aloft. But strong winds, particularly in tropical storms and tornadoes, are known to move objects far larger than sand over short distances. Now, in the high Andes of Chile on the Salar Gorbea salt flat, evidence has been found of tornadic “gravel devils” whipping across the landscape and transporting gypsum crystals as long as 27 centimeters.

16 Jun 2017

Ceres' homemade organic materials

Researchers analyzing data from NASA’s Dawn spacecraft have found signs of organic compounds that arose on the surface of Ceres, a dwarf planet one-fourth the diameter of our moon in the asteroid belt between Mars and Jupiter. The compounds’ origins may provide clues about how life on Earth got started.

09 Jun 2017

Red Planet Roundup: June 2017

With two rovers patrolling the surface of Mars, six spacecraft orbiting above it, and scientists here on Earth studying the Red Planet from afar, new findings are announced often. Here are a few of the latest updates.

08 Jun 2017

Horses evolved to get along: Competition between species not main evolutionary driver

Horses have changed size and shape dramatically over the last 20 million years, evolving from small dog-sized creatures with multiple toes into the large, hoofed grazing animals we see today. But the factors that drove these changes have been unclear. In a new study in Science, scientists tested the long-held theory that horses evolved rapidly to compete with one another during the worldwide expansion of grasslands starting 18 million years ago.

07 Jun 2017

The mackerel year: Tambora changed how New England fished

The 1815 eruption of Indonesia’s Tambora Volcano led to a 1- to 1.5-degree-Celsius drop in the average global temperature, prompting 1816 to be called the “year without a summer.” New research analyzes weather data and historical records from New England to explain why, in the northeast U.S., 1816 was also called the “mackerel year.” As eruption-induced extreme weather triggered food scarcity in some areas, including a reduction in alewife numbers along the U.S. Atlantic coast, fishermen in the Gulf of Maine turned to mackerel fisheries farther offshore that had been neglected while more easily fished coastal and freshwater species were available.

06 Jun 2017

Pages