Kelvin-Helmholtz clouds, also known as ‘billow clouds’, look like rolling ocean waves in the sky. The clouds often form on windy days, when two air currents of varying speeds meet in the atmosphere. It’s believed that this kind of clouds inspired the swirls in van Gogh’s ‘Starry Night‘.
Thermogenic plants have the ability to raise their temperature above that of the surrounding air. They can generate their own heat and flower earlier in the season than almost any other plant. Botanists are not completely sure why thermogenic plants generate large amounts of excess heat, but most suspect the flowers may be doing this to attract coldblooded insect pollinators. Thermogenic plants are found in a variety of families, but Araceae in particular contains many such species. Here’s some examples.
Symplocarpus foetidus, commonly known as skunk cabbage, is a low growing plant that grows in wetlands and moist hill slopes of eastern North America. Bruised leaves present a fragrance reminiscent of skunk.
Skunk-cabbage in snow – Photo via Ryan Johnson/Flickr
In meteorology, a virga is rain falling from a cloud that evaporates before reaching the ground. At high altitudes the precipitation falls mainly as ice crystals before melting and finally evaporating. The phenomenon is very common in deserts, where low humidity and high temperatures can cause rain to evaporate shortly after being released by clouds. You might see virga in the U.S. West and above the Canadian Prairies, in the Middle East, Australia and North Africa.
Continue reading Virga – rain that doesn’t reach the ground
Batagayka crater in Siberia, known as the “gateway to hell” by locals, is almost 1 kilometer in length and 86 meters in depth. The structure is named after the near-flowing Batagayka, a right tributary of the river Yana. The land began to sink due to the thawing permafrost in the 1960s after the surrounding forest was cleared. Flooding also contributed to the enlargement of the crater. Archeologists have found ice age fossils buried in the mud around the rim of the crater. The rim is extremely unstable as there are regular landslides into the crater and the permafrost is constantly thawing. The Batagayka crater is making noises too as it consumes large chunks of the area. The crater is currently growing in size and it will likely eat through the entire hill slope before it slows down. Frank Günther of the Alfred Wegener Institute in Potsdam, Germany, showed that over the past decade crater grew by an average of 10 meters per year.
By NASA Earth Observatory images by Jesse Allen, using Landsat data from the U.S. Geological Survey. – https://earthobservatory.nasa.gov/IOTD/view.php?id=90104&src=eoa-iotd, Public Domain, Link
“The ground looks like it’s breathing in this Quebec forest,” wrote user Daniel Holland on twitter. According to the Forbes report, air is involved in this illusion, as strong wind plays a role in moving the trees and the topsoil. During a storm the ground becomes saturated with water, loosening the soil’s cohesion. As strong winds move the top of the tree, the force is transferred by the stem, acting as a lever, to the roots and the ground begins to move.
The wind caused the trees to sway, roots and all. In fact, the whole floor seems to rise and fall as if the earth itself was breathing. The phenomenon works best with spruce trees with their almost disc-shaped root system growing in the uppermost layers of the soil.
A snow roller is a rare meteorological phenomenon in which large snowballs are formed naturally as chunks of snow are blown along the ground by wind, picking up material along the way, in much the same way that the large snowballs used in snowmen are made. Unlike snowballs made by people, snow rollers are typically cylindrical in shape, and are often hollow since the inner layers, which are the first layers to form, are weak and thin compared to the outer layers and can easily be blown away, leaving what looks like a doughnut or Swiss roll. (Source Wikipedia)
Oregon is home to the towering Cascades, a range of mountains and active volcanoes. The Lost Lake likely formed about 3,000 years ago, when lava flowing from a volcanic vent blocked a river channel and created the lake. The lake bed begins to fill in the late fall, when the amount of rain coming in starts exceeding the ability of the lava tubes to drain off the water. But during the dry months, the lake vanishes and turns into meadow. The reason? Two hollow lava tubes at the bottom of the lake are constantly draining the lake dry, much like a bathtub left unplugged. It’s not entirely clear where the water goes, but it possibly seeps into the porous subsurface underground. There have been numerous attempts to plug the leak, those endeavors, however, would only result in the lake flooding. Continue reading Oregon’s ‘Lost Lake’ disappearing through lava tubes