Earth’s landmasses were not always what they are today. Continents formed as Earth’s crustal plates shifted and collided over long periods of time. This video shows how today’s continents are thought to have evolved over the last 600 million years, and where they’ll end up in the next 100 million years.
Kinda cool:
More than half of all the world’s volcanoes (over 450) are found in the Pacific ‘Ring of Fire’. This area forms a circle stretching down the eastern side of the Pacific Ocean, from Alaska in the north, through the Rocky Mountains of Canada and the USA, to the Andes mountains of South America. It loops back around the western side of the Pacific, up through New Zealand, Indonesia and Japan.
Unsurprisingly the Pacific ‘Ring of Fire’ also experiences lots of earthquakes.
The image above, which plots earthquakes of magnitudes 4.0 or greater from 1898 onwards, shows just how active our planet is. The map’s data is valid up until 2003, but the 105-year period it covers includes 203,186 earthquakes. Learn more here.
Desert sun overhead, volcanic forces beneath your feet, and the average year-round temperature is 34°C (93°F)! This is Danakil Depression in Ethiopia, where the ground springs forth with lava and hot mineral springs that evaporate and leave salt formations behind.
See a collection of beautiful and foreboding photographs of the region here or learn more here.
As Arctic sea ice breaks apart, massive amounts of methane could be released into the atmosphere from the cold waters beneath.
High concentrations of the greenhouse gas have been recorded in the air above cracks in the ice. This could be evidence of yet another positive feedback on the warming climate – leading to even faster Arctic warming.
The Arctic is home to vast stores of methane – there are billions of tonnes of methane in permafrost alone. It is a potent greenhouse gas, so a major methane release would greatly accelerate climate change. The gas is found in icy crystals called hydrates beneath the shallow seas that flood some areas of the continental crust, as well as in permafrost. It is also being released from Arctic wetlands.
The question now is: how significant will this new effect on warming be? It might be small or it could be another serious problem. Learn more here or here.
Excuse you. Researchers have found that immense herbivorous dinosaurs may have produced enough methane gas—essentially burps and farts—to substantially boost global temperatures. The group of dinosaurs known as sauropods—plant eaters famed for their long necks and gargantuan size, such as those shown in an artist’s reconstruction below—were common members of many ancient ecosystems.
Previous research hints that each square kilometer of well-vegetated area may have supported between 11 and 15 sauropods, which together could have weighed about 200 metric tons. Using methane-production data for modern gut bacteria, researchers estimate that over the course of a year, sauropods worldwide would have produced about 520 million metric tons of the greenhouse gas. That’s roughly the amount of methane entering the atmosphere each year from all of today’s sources combined—including agriculture, beef and dairy production, wetlands, and forest fires.
Because methane has about 25 times the planet-warming power of carbon dioxide, the gas generated by sauropods alone could have warmed the planet almost as effectively as all of the carbon dioxide in today’s atmosphere. Learn more here, here, here or here.
Here is a picture that gives you a perfect idea of how much water there is on Earth compared to the solid materials that form its main body. It’s truly staggering.
This picture shows the size of a sphere that would contain all of Earth’s water in comparison to the size of the Earth. The blue sphere sitting on the United States has a diameter of about 1,385 kilometres, with a volume of about 1,386,000,000 cubic kilometres. The sphere includes all the water in the oceans, seas, ice caps, lakes and rivers as well as groundwater, atmospheric water, and even the water in you, your dog, and your tomato plant. Learn more here.
Taking into account human spacecraft going up and cloaked alien ships coming down, is the Earth gaining or losing mass? Some scientists have accounted for all of the material leaving and arriving on Earth.
Overall, they have calculated that the Earth – including the sea and the atmosphere – is losing mass. They points to a handful of reasons.
For instance, the Earth’s core is like a giant nuclear reactor that is gradually losing energy over time, and that loss in energy translates into a loss of mass.
But this is a tiny amount – no more than 16 tonnes a year.
And what about launching rockets and satellites into space, like Phobos-Grunt? Scientists discount this as most of it will fall back down to Earth again.
But there is something else that is making the planet lose mass. Gases such as hydrogen are so light, they are escaping from the atmosphere.
The conclusion is that the Earth loses 50,000 metric tonnes each year. Fortunately, compared to the immense size of the world, this is a tiny difference, a loss of just 0.000000000000001%. It would take trillions of years to empty the earth’s oceans and since the planet is only about 5 billion years old, there is nothing to worry about. Learn more here.
Pangea is a supercontinent that included all the landmasses of the earth before the Triassic Period. Pangaea broke apart during the Triassic and Jurassic Periods, separating into Laurasia and Gondwanaland. Further separation over millions of years has lead to the continents we see today.
But change is continuing!
In the future there will be a geological showdown for the ages, with North America, South America, Europe and Asia colliding head-on over the North Pole to create a supercontinent called Amasia.
Unfortunately, nobody we know will be around to watch the collision, which won’t happen for another 50 million years or more. But it’s still fun to imagine. Learn more here.
I’ll start with the answer: Everyone is wrong about how people die when they fall into lava.
Gollum, if you remember, dove into the lava of Mount Doom after his precious ring was thrown in — he proceeds to sink into the lava (see below) and leaves the ring floating on the lava until it melts away. Guess what? Sinking into lava just will not happen if you’re a human (or remotely human). You’d need to be a Terminator to sink into molten rock/metal … and here’s why.
Molten lava is nothing like water. Sure, everyone thinks that liquid rock (magma) is going to behave like any other liquid (e.g., water), but there are some key physical properties that tell us it just isn’t the case. Let’s compare!
Pa·s is the SI unit for viscosity — some people might be familiar with other viscosity measures like poise. Viscosity is, more or less, the resistance to flow, so if you throw something in a liquid, a low viscosity liquid (like water) will “get out the way” and you’ll sink faster relative to a high viscosity liquid (like honey). The density of the liquid will also play a role in how quickly you might sink based on your own density. So, when we’re looking at water versus lava, lava is ~3.1 times the density and between ~100,000 to 1,100,000 times the viscosity. They are very different! As a result humans WOULD NOT sink into lava, they would just sit on top and burn, which would still be quite nasty!
So, there you have it. The next time you see someone in a movie fall into a cauldron of roiling lava and they sink into it, remember that it can never happen. Learn more here.
