"Our loyalties are to the species and the planet. We speak for Earth. Our obligation to survive and flourish is owed not just to ourselves, but also to that Cosmos, ancient and vast, from which we spring." - Carl Sagan
NASA released an animation yesterday showing the development of a storm system that generated several violent tornadoes in the South over the weekend.
South America’s second largest river, the Paraná River (and its tributaries) is seen here in this astronaut photo acquired on April 9, 2011, revealing an 18-mile-across (29 kilometers) expanse of the river downstream from Goya, Argentina. - NASA Earth Observatory [x]
A “did you know” for you. Red beds and banded iron formations tell us that oxygen began to build up in our planet about 2.3 billion years ago.
These are not the product of photoshopping, pharmaceutical chemical run-off or man made dyes. These are naturally occurring lakes.
Lake Hillier in Western Australia is teeming with salmon pink water.
Likewise, Lake Retba in Senegal is so milkshake pink that its water looks good enough to drink.
To find out why these bodies of water look so bubblegummy, researchers from the University of Bath (for real, no watery pun intended) in the UK examined pink lake H20 under their microscopes and found that:
The lakes are saltier than the sea
Almost ten times saltier than the regular ocean in fact. This high salinity (up to 40% salt in solution) makes the lake just like the Dead Sea where swimmers are so buoyant that they float around due to its high density compared to their body mass.
The lakes are full of algae and bacteria
Samples of the H20 when examined under the microscope reveal large quantities of the salt loving micro-algae Dunaliella salina and halophilic bacteria. The law of osmosis tells us that water moves from regions of high concentration to regions of low concentration in the presence of a semi-permeable membrane. Most cellular organism therefore would shrivel up and die when placed in the high saline environment of these lakes because all of their water would move out of their cells into the surrounding lake across their semi-permeable plasma membranes by osmosis. D. salina, however, can survive in these conditions. It does so by synthesizing large volumes of glycerol in the cytoplasm of its cells to counter-balance the effects of osmosis resulting in no net move of water across its membranes (Oren, 2005). This makes them highly suited to life in a salty lake but it doesn’t explain the pink hue to the lake.
The algae and bacteria makes carotenoids
D. salina has been known to medicine for a long time. The algae was of interest to scientists who wondered how these organisms could survive and thrive in salt flats that have dried out due to water evaporation during periods of extreme heat and sunlight exposure. They do so because they can tolerate the high levels of solar radiation by synthesizing large amounts of β-carotene, an antioxidant that protects cells from damage and is used to produce Vitamin A - both of which are substances now used in cosmetics, skin care products and sunscreens. Sweet potatoes and carrots are also rich in β-carotene which gives them their distinctive pink/orange colors. A color similar to the carotenes produced by the microorganisms in the lakes and therefore contributing to their unique pinkness (Oren, 2001).
Pink lakes, an amazing natural mystery with a simple microscopical solution (also a great vacation spot for Barbie).
1. Oren A. “A century years of Dunaliella research: 1905-2005.” Saline Systems, 2005.
2. Oren A. and Rodriguez-Valera F. “The contribution of halophilic Bacteria to the red coloration of saltern crystallizer ponds.” FEMS Microbiology Ecology, 2001.
The beautiful, sad, shifting state of wild ice: Geomorphologist / photographer James Balog travels the globe to capture the twisting, soaring forms of the world’s vanishing wild ice. In 2009, he wowed the TEDGlobal crowd with his time-lapse photos of the shifting landscapes of the world’s icy habitats.
Above, some striking footage from his project Extreme Ice Survey.
The meanderiness of a river, its Stølum number, is defined as the length the water travels from source to finish (blue curve) divided by the direct distance (red line). This can change chaotically as a river changes coarse, forming Ox bow lakes. The ratio is often found to converge to (but rarely exceed) 3.14, roughly pi. [more] [code] [thanks] [thanks2]
Mount Huascarán, Peru
The snow-capped mountains running through the centre of this satellite image are part of the Cordillera Blanca – or ‘white range’ – in South America’s Andes. Even though they are part of the typically warm Tropics – the region of Earth surrounding the equator – the mountain range is high enough to be permanently covered in snow and ice.
There are hundreds of glaciers in this range, providing a major source of water for irrigation and hydroelectric power. The glaciers and snow-covered areas ‘collect’ rain and snow during the rainy season and slowly release it during the drier times of the year. Over the last decades, the glaciers have experienced major losses owing to climate change, causing a major threat to water supply during the dry season in the future.
Located near the centre of this image, Mount Huascarán is the highest peak in Peru at 6768 m. The summit is one of the farthest points from Earth’s centre, meaning it experiences the lowest gravity on the planet.
North of Huascarán, we can see an outlet glacier that meets another outlet from the Chopicalqui mountain to the east. Numerous blue glacial lakes are visible in the valleys between the mountains.
Image credit: JAXA/ESA
The (West Antarctic Ice) Sheet Has Hit The Fan
Well, now we’ve done it.
This week, two scientific teams reported that the collapse and melt of large portions of the West Antarctic Ice Sheet now appears unstoppable. As in irreversible, inevitable, and more than partially our fault. There’s enough water in the unstable ice sheet to raise global sea levels by four feet on its own, and combined with other sources of melt, this could raise sea levels as much as ten feet over the next few centuries.
I’ll give you a moment, in case that didn’t sink in.
As Chris Mooney writes at Mother Jones, “This is what a holy shit moment for global warming looks like.”
The acceleration of the ice sheet’s melting is due to warming ocean currents, destabilizing the ice from beneath and speeding up its collapse. Because of the particular geography of the region, this rapid chain reaction of melting can not be stopped. If greenhouse gas levels continue to rise, this melting will only speed up.
If there’s any silver lining to this news, it’s that it’s not clear how fast this will happen. Ice sheets move slowly (being made of ice and all), so the melt could play out over hundreds of years. Still, it’s the clearest sign yet that we have irreversibly affected the global climate, and we must do something.
Every day that we spend faux-debating the validity of climate change science is another day closer to an inevitably wet future. Would you rather build a boat or tread water?
PS - The image up top shows what Times Square would look like with 6 feet or so of sea level rise. Just so you know what to expect. Check out more at worldunderwater.org
Richat structure, Mauritania
A giant, geological wonder in the Sahara Desert of Mauritania is pictured in this satellite image.
The 40 km-diameter circular Richat structure is one of the geological features that is easier to observe from space than from down on the ground, and has been a familiar landmark to astronauts since the earliest missions.
Once thought to be the result of a meteor impact, researchers now believe it was caused by a large dome of molten rock uplifting and, once at the surface, being shaped by wind and water into what we see today. Concentric bands of resistant quartzite rocks form ridges, with valleys of less-resistant rock between them.
The dark area on the left is part of the Adrar plateau of sedimentary rock standing some 200 m above the surrounding desert sands. A large area covered by sand dunes – called an erg – can be seen in the lower-right part of the image, and sand is encroaching into the structure’s southern side.
Zooming in on the southern side of the bullseye, we can see individual trees and bushes as tiny dots. These follow a river-like structure that appears to have been dry when this image was acquired, a few weeks after the rainy season. Some areas to the south and east of the Richat appear to be covered with temporary lakes, which are dry for most of the year.
Image credit & copyright JAXA/ESA