The Earth Story

Airglow over the Atacama One of the several rising steps that climbs to the main cordillera of the Andes through the driest desert on Earth resembles a beach abutting onto a sea of clouds below and provides the backdrop for this gorgeous photo of airglow above the southern skies with our galaxy in the sky above. The ripples are caused by atmospheric waves and produce a completely different pattern to those in the skies above the Tibetan Plateau I shared once before (see http://on.fb.me/1MC62j0).

What is acid mine drainage? Acid Mine Drainage is one of the main environmental problems found at the Earth's surface. It is triggered by exposed rocks from old, inactive mines, and billions of dollars are spent yearly managing it. One example is seen here, in this photo from an old mine (and now Mushroom farm) in Ohio, but what is it that has turned this water red? Our story begins, like many on Earth, 4.56 billion years ago. When the Earth formed, its atmosphere was chemically in equilibrium with the rocks in the mantle. Oxygen is the most abundant element in the mantle, but all that oxygen is taken up bonding with elements like silicon, magnesium, and iron. There was so much of these elements that there was no oxygen left in the atmosphere – the planet’s atmosphere started off reducing, filled with gases like methane that would burn in today’s atmosphere.

Right Time, Right Place: Earth’s Magnetic Poles If you were to list factors crucial to life on Earth—water, oxygen, appropriate temperature—magnetism might not make the list. But it should, because without Earth’s magnetic poles, we probably wouldn’t be here. Magnetic poles may be one of the most important things we never think about it. Let’s meet the two major players in this unique scenario: Earth’s magnetic field and solar winds.

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Video and photo by @babaktafreshi

| This is a time-lapse video of what I experienced near midnight last May in West Texas. Red sprites are large-scale electrical discharges occurring in clusters about 50 to 90 kilometers (31 to 56 miles) above the ground. They appear above massive storm clouds. The time-lapse video briefly freezes on the sprites so you can see them better. To the unaided eye, they are usually a featureless, colorless flashing patch of gray. Most people miss them unless they are looking for them patiently. Music by Tonelabs Studio.

The Big Stump Florissant Fossil Beds National Monument in Colorado is centered around an Eocene aged lake in Colorado – making it 34 million years old. Because CO2 contents in the atmosphere were higher in the Eocene, the climate was warmer globally and the plants at this site record the difference.

Thunderbolt and Lightning very very frightening me! As a child thunderstorms terrified me, the loud booms of thunder and bright flashes of lightning were enough to convince me the apocalypse was here. To try and reassure me that the house wasn’t about to be set ablaze by a rogue fork of lightning, my dad told me to count the seconds between lightning and thunder to estimate how far away the storm was. The general rule of thumb would be one mile for every second between lightning and thunder, and I generally did feel better when I knew a storm wasn’t directly overhead. To this day I still count the seconds between lightning and thunder as a rough gauge of how far away a storm is and how long it will be until it hits. But what’s the science behind it all and does it really work?

Lux Aestiva is a celebration of ever-changing light of summer in Finland. These hyperlapses were shot during June and July 2020 in various locations in Southern Finland: Turku, Kaarina, Lieto, Salo and Parainen.

Warming Earth, Warming Atmosphere This image is one you might see commonly during the winter, showing the difference between types of freezing and wet precipitation. If there is warm air near the surface, generally precipitation hits the ground as rain, while cold air near the surface allows it to snow or sleet. Even outside of winter storms, the same phenomenon occurs; high in the atmosphere, water is frozen as ice particles, but closer to the surface everything melts to become rain. Over the time where there are solid weather records, the surface of the Earth has warmed by just over 1°C. 

Nacreous (‘mother of pearl’) cloud Nacreous clouds, also known as polar stratospheric clouds (PSCs), appear high in the atmosphere, some 15 to 30km (10 to 20 miles) above the Earth, generally in latitudes higher than 50°, particularly in the northern hemisphere. They form in the freezing temperatures of the lower stratosphere, often below -80°C (-112°F), and are usually a mixture of nitric acid and ice crystals, sourced from parcels of moist air that are forced up through the tropopause by the same orographic oscillations that are responsible for producing high lenticular wave clouds.

Wave clouds shimmering off the Kuriles Dropping southwards down the sea of Okhotsk from Russia's Kamchatka peninsula towards Japan, these islands are a volcanic arc born of the subduction of the Pacific oceanic plate under the Okhotsk micro plate. Stretching some 1300km along the rim of fire this line of 56 stratovolcanic peak also divides ocean from sea. There are a hundred or so volcanoes in the chain, 40 of which are very active. The amazing image snapped by NASA's AQUA satellite shows how the chain affects air masses. The winds of the building storm system are leaping over the peaks, and forming turbulent patches of air behind the isles, creating the pattern of wave clouds. Loz Image credit: NASA https://go.nasa.gov/31lKF47

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Noctilucent Cloud Season Begins for Northern Hemisphere Noctilucent clouds (NLC) are the highest cloud formations on our planet. In this photo from the International Space Station, they are the blue wispy layers seen at the top of the atmosphere. They mostly form at latitudes of 50° or higher, with the majority found in polar regions during the summer. We've previously covered them (http://on.fb.me/1HHqVDj, http://on.fb.me/1RG4UvU), but we may know a little more about them now thanks to NASA’s Aeronomy of Ice in the Mesosphere (AIM) mission (http://on.fb.me/1FpEruW).

The morning glory over Cape St Vincent Also known as roll clouds, no one knows exactly how they form, but these tubes can be thousands of kilometres long and (often but not always) appear in the early morning along coastlines. It is thought to be due to a circular air current pattern creating tube like zones of condensation when strong breezes blow inland off the sea. They are accompanied by turbulent winds and surface jumps in atmospheric pressure. We get them every now and again in my home city of Montevideo, forming along the length of the Rio de la Plata just offshore, sometimes in long perfect tubes, sometimes amazing ragged wind sheared formations. This one was shot off the coast of Portugal. Loz Image credit: Vanda Rita via APOD

Comparing Terran and Martian sunsets The two photos here have been scaled to depict the same angular width, so that the sinking solar orb and the dance of its light in the atmospheres of two worlds could be viewed side by side. The most obvious difference is the colour, an eerie bluish grey on Mars contrasted with the deep multicolour palette of a wordly evening. There are several reasons for this, one being the layered nature of our atmosphere, and the contrasts in dust and aerosol content between the layers. Another may be the nature of the dust: scientists don't understand as yet why the Martian examples have a bluish tint, but speculate that something in the nature of Martian dust and its interaction with light is probably the cause. The Arean orb also appears slightly smaller than ours due to the greater distance of Mars' orbit around the sun. Loz Image credit: Damia Bouic/NASA/CURIOSITY

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