What’s bad about melting ice sheets?

New York Times Imagine a huge slab of ice with an area of about 200 square miles – if it was ever to melt it would release torrents of water into the oceans. The problem is that it already is melting – scientists with the British Antarctic Survey discovered last week that an iceberg that big has just broken away from a major Antarctic ice sheet. Now that the ice has been separated from the ice sheet, it will quickly disintegrate, and before long it will all have melted.

CNN OK, so this iceberg might raise sea levels a fractional amount. But does it really mean anything in terms of the big picture? Or did the media just hype up the story to bring in some more page hits and viewers? Although this event alone is not going to be devastating for our planet, the fact that it happened raises a whole load of worrying issues.

For a start, it’s clear evidence that Antarctica is warming faster than pretty much anywhere else on our planet. Aside from melting ice, why does that matter? Well, it certainly does matter – already, the population of krill (tiny shrimp-like creatures) has been dropping quite substantially because of the warmer waters. Krill is the primary food of loads of other marine organisms, so kill the krill and you’re also killing a multitude of species of fish.

CNN Another effect that’s fascinating is that the warmer Antarctica gets, the more it snows, and that snow decreases the chance of penguin eggs hatching successfully. What? Rising temperatures increase snowfall? I know it sounds weird, but it’s true – warmer temperatures give the air a higher humidity, causing more snow to fall.

Carbon Dioxide, the gas the virtually all scientists believe is causing global warming, is also having a direct effect on animals, not just by increasing the temperatures. Water is really good at absorbing that dreaded greenhouse gas, but this has the unfortunate consequence of turning the water more acidic. That then means that organisms with shells get their shells weakened by the acid, as well as suffering loads of other knock-on effects. (Read more about the effects of acidic waters in my previous post – aptly named ‘Climate Change won’t just kill Polar Bears’)

You might think that this post was a bit depressing – but that’s not how I want you to feel. Hopefully it’ll inspire you to do something, and make you realize that you yourself can play a big part in stopping climate change going too far. I know we are capable of doing it, but can we be bothered? Can you be bothered? Go on, give it a try. 🙂

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The surprising animals discovered in Antarctica

MSNBC / AP You wouldn’t think the icy cold waters around Antarctica would be home to much more than a few micro-organisms, perhaps the odd fish or two. But as it has done so many times before, nature has once again shown how life can thrive in the most unusual places.

A 50-day, 2000-mile journey through the Ross Sea by scientists has discovered a whole range of weird new creatures. Take the two-foot wide starfish, for example. How did it get so big in such harsh conditions? What about jellyfish with tentacles 12 feet long, and huge sea snails? In fact, it is thought that hundreds of new species will be identified as a result of the mission – not what you’d expect from Antarctica. (Click here for an excellent Antarctica interactive)

Wikipedia Amazingly, the cold temperatures may actually help the animals that live in Antarctic waters. Because it’s too could for most predators, any animals there are quite safe, so can grow for years without being eaten up. Because it is so cold, the life processes of some of the animals are slowed down, giving them a greater lifespan than they would otherwise have, which gives them more time to grow. There are also high levels of oxygen in the water.

I’m always amazed when we discover life in another seemingly uninhabited area – it just shows how versatile life is. Let’s just hope that humans don’t destroy any more new species before we even discover them.

Scientists: Earthquakes can be caused by global warming

Melting ice sheet in Alaska | Image: National Geographic I get really annoyed whenever there’s an earthquake and people say “it’s all because of global warming”. There is no doubt that climate change influences hurricanes and droughts, but earthquakes, tsunamis and volcanoes are all down to Earth’s natural processes.

Well at least that’s what I used to think, up until now. New research suggests that maybe I shouldn’t have been getting so annoyed with those people after all, because there may actually be a direct link between climate change and earthquakes. How on Earth is that possible, because what has the atmosphere – which causes global warming – got to do with the inner workings of our planet (which cause earthquakes)?

Damage from the February 2008 Nevada quake | Image: CNN The science behind it is surprisingly simple. Because ice sheets become so huge, they ‘glue’ the land underneath them together. This prevents earthquakes happening because the power of the earthquake would not be enough to overpower the force of the ice which is holding the land together. 

So any stress building up between Earth’s tectonic plates carries on building up and building up, unable to be released. (In case you don’t know, tectonic plates are the massive lumps that make up the Earth’s surface, and can cause earthquakes by sliding past each other or colliding.) This is great as long as the ice is there, because it means there are very few earthquakes.

Map of the world's major tectonic plates. There are many smaller plates that also cause earthquakes | Image: johomaps.com

The problem comes when the ice melts: once the ice isn’t there to ‘glue’ the tectonic plates together, all the stress between the tectonic plates will suddenly be released. Depending on how fast the ice is melting, this stress could be released in a series of mini-quakes (if the ice is melting slowly) or a disastrous giant quake (if the ice melts really fast).

Isn’t this all just a big scare story – where’s the evidence? Well actually, the whole study was based on real evidence. Scientists found that a series of earthquakes near the Arctic around 10,000 years ago matched the time when the ice started melting, after the end of the last Ice Age. And they even managed to trace the quakes going gradually northward, as the ice retreated further north.

Every day the effects of human-induced global warming seem to get worse and worse. But it doesn’t have to be that way – small changes to our lives really can make a big difference.

NASA releases new images of the moon with geysers: Enceladus

Enceladus, as photographed by Cassini | Image: NASA / MSNBC

Enceladus, as photographed by Cassini | Image: NASAThese images show Saturn’s moon Enceladus, as captured by the Cassini spacecraft. It recently flew through the plumes from Enceladus’s icy geysers, and took some photos either side of the flyby.

The surface of Enceladus may look like rock, but it is actually ice.  Amazingly, there may even be a liquid water ocean underneath. Unforunately we’ll have to wait a while yet for the results of the geyser flyby to come back, but in the meantime…

Click here for more information on the flyby and on Enceladus’s mysterious geysers.

NASA probe flying through the icy geysers of Saturn’s moon Enceladus

Cassini, a collaborative venture between NASA, ESA and the Italian Space Agency | Image: Wikipedia Until a couple of years ago, Saturn’s moon Enceladus (that’s en-sell-uh-duhs) was thought to be pretty boring – it was just another cold lump of rock like our own Moon. But then two years ago, the Cassini probe discovered something that revolutionized our view of Enceladus: around its South Pole are geysers spewing ice, dust and gas into space. In fact, Enceladus is also thought to be one of the most likely places in our Solar System to find life.

Now, Cassini is flying back to discover more about Enceladus, but it’s doing something a bit different to what space probes usually do. It will fly directly into the fountains of material above the geysers, sometimes at a height of just 30 miles above the surface. Rather than just taking photos, it will collect samples of the material that the geysers are releasing, and analyze it to see what its chemical composition is like. Click here for NASA’s Enceladus Flyby blog.

Saturn's icy moon Enceladus | Image: NASA / CNN But it’s not just huge geysers that make Enceladus interesting. Think how Yellowstone’s Old Faithful works – it’s all down to the heat of the Earth warming up the water so that it shoots upward. It’s not much different on Enceladus – in fact, Enceladus is a very geologically active body, and is among only two other Solar System bodies that have been seen erupting (the other two are Jupiter’s moon Io and Neptune’s satellite Triton).

Unlike on Earth where magma is the hot material, it is thought to be water-based on Enceladus's icy plumes | Image: NASA / JPLEnceladus. What causes the heat in a body so far away from the Sun? The main theory is that Saturn’s gravitational pull causes ‘tidal friction’, which generates heat in this otherwise icy moon.

Wait a minute… water, heat – they’re two key ingredients for life. It is indeed one of the places NASA is concentrating on in the search for ET. Enceladus is fast turning into one of the most exciting, revolutionary places in our Solar System – I can’t wait for the discoveries to come in the weeks and months ahead.

Check out this great post by Kate Tobin on CNN’s Sci-Tech blog. | This new interactive from NASA is a great resource for Enceladus – the intro video at the good is excellent. | Also, NASA has just released a site that lets you fly along with Cassini as it explores Saturn and its moons. It’s pretty cool in my opinion.

UPDATE: NASA has now released some of the images from this flyby. Click here to see them.

Avalanche on Mars: NASA releases stunning images

What happens when you disturb some ice at the top of a cliff that’s half a mile tall? Check out this image for the answer:

The first Martian avalanche ever photographed | Image: NASA

And that cloud of dust in the image above isn’t just any old avalanche – it’s an avalanche on Mars! As if that wasn’t spectacular enough, there were actually four avalanches in total, all captured in the same image (click here).

So what’s in that billowing red cloud? It’s almost all a mixture of frozen carbon dioxide and Martian dust, although there may have been some huge chunks of rock in there too. If a human was standing at the bottom, chances are they’d have been completely swept away.

Talking about standing at the bottom, if you were in that unlucky position, you wouldn’t have had much time to run away because even though the cliff was over 2,300 feet high, its slopes descended at the incredibly sharp angle of angle of over 60 degrees.

Mars Reconnaissance Orbiter | Image: NASA The amazing thing about this image is that nearly every other image of Mars is static, because the Red Planet’s surface remains much the same for millions of years. To see this avalanche in progress required a huge amount of luck, especially as the probe that snapped it (NASA’s Mars Reconnaissance Orbiter) was investigating something unrelated at the time.

The big question puzzling NASA is working out why the avalanche happened. The main theory at the moment is that some of the ice melted, causing disturbances that triggered a massive avalanche – the image was taken in Martian spring, when the planet was starting to warm up after the winter.

But another interesting, though unlikely, theory is that a small asteroid crashed into the cliff, unleashing the cloud of dust and ice. Alternatively, there may have been an earthquake (sorry, Mars-quake).

Mars | Image: National GeographicWhatever caused it, this avalanche image is one of the most stunning things to come from Mars exploration in quite a while. I’m looking forward to the day when probes start having video capability – that would make stunning moments like this just extraordinary.

Penguins… What else lives in Antarctica?

Penguins and seal on an island off Antarctica | Image: National Geographic

We all know penguins live in Antarctica, but what else? On land, pretty much nothing except the odd seabird or insect. But in the seas that surround the South Pole, a huge collection of intriguing and strange creatures inhabit the oceans.

Glass tulips | Image: National Geographic

Glass Tulips

Two new studies have revealed even more of these creatures’ strangeness – take a look at these ‘glass tulips’ (right) that are actually living animals.

Giant worms | Image: National Geographic

Giant worms

And then there are giant worms (left), 10 inches long, that look suspiciously like trilobites, ancient creatures which roamed the oceans millions of years ago.

Icy fish

Here’s a weird fish, (below) that lives in the depths of the Antarctic oceans. Little is known about this fish yet, but some fish living in icy waters have a biological antifreeze that circulates around their body to stop them from icing up.

The woman who discovered this fish named it in honor of her fiance… I hope he didn’t take it as an insult.Icy fish | Image: National Geographic