Beautiful Ice Window Amazing World
Beautiful Ice Window Amazing World
The Ten Commandments of Logic
Logic the basis of science
Acres of colour sprawl across the landscape, highlighting the patchwork rainbow of Holland’s tulip fields. Photographer Normann Szklop hired a small plane for the shoot. Picture: Normann Szkop / Rex Features (via Pictures of the day: 4 February 2013 - Telegraph)
Taylor Valley, Antarctica
While flying over Antarctica aboard a P-3 aircraft in November 2013, Operation IceBridge project scientist Michael Studinger took this photograph of Taylor Valley, one of Antarctica’s unique dry valleys. Home to Taylor Glacier, striking rock outcrops, and Blood Falls, the valley is one of the most remote and geologically exotic places in the world.
While ice and snow covers most of Antarctica, Taylor Valley and the other dry valleys are conspicuously bare. Inland mountains—the Transantarctic Range—force moisture out of the air as it passes over, leaving the valley in a precipitation shadow. The lack of precipitation leaves dramatic sequences of exposed rock. In the photograph, the tan bands are sandstone layers from the Beacon Supergroup, a series of sedimentary rock layers formed at the bottom of a shallow sea between 250 million and 400 million years ago. Throughout that period, Earth’s southern continents were locked into the supercontinent Gondwana.
The dark band of rock that divides the sandstone is dolerite (sometimes called diabase), a volcanic rock that forms underground. The distinctive dolerite intrusion—or sill—is a remnant of a massive volcanic plumbing system that produced major eruptions about 180 million years ago. The eruptions likely helped tear Gondwana apart.
The dominant feature in the photograph—Taylor Glacier—is notable as well. Like other glaciers in the Dry Valleys, it is “cold-based,” meaning its bottom is frozen to the ground below. The rest of the world’s glaciers are “wet-based,” meaning they scrape over the bedrock, picking up and leaving obvious piles of debris (moraines) along their edges.
Cold-based glaciers flow more like putty, pushed forward by their own weight. Cold-based glaciers pick up minimal debris, cause little erosion, and leave only small moraines. They even look different from above. Instead of having surfaces full of crevasses, cold-based glaciers are comparatively flat and smooth.
At the lower right of the photograph, “Blood Falls” appears as a small, dark smudge. The name refers to the stain of red that coats part of the glacier and seeps down toward Lake Bonney in a pattern that makes it look like a blood-red waterfall. The red comes from microbes living within a pool of ancient seawater that has been trapped beneath Taylor Glacier for at least 1.5 million years. Due to the activity of the microbes, the seawater is enriched with ferrous hydroxide (an iron-containing salt), which quickly oxidizes and turns red as it seeps out of a crack in the glacier.
Image credit: NASA Earth Observatory images by Robert Simmon
The earth is commonly called the “Goldilocks” planet. At 149.60×106 km (1a.u) away from the sun, it is neither too hot nor too cold. This blue planet, our home, is the only place known to harbour life; this is both to our delight and our detriment. With intelligent life comes the ability to alter our planets systems. With the dramatic increase of greenhouse gases and the accompanied destruction of much of our rainforests; we as a global nation are at a critical time in the earth’s history. We may see ourselves as lucky, situated in the solar system at a location where water is liquid and the atmospheric composition is one which not only supports life but allows life to thrive. We should hold this view carefully; we need only look towards Venus and Mars to see just how different our luck could have been, and how desolate and uninhabitable our beautiful home could become. Venus, Earths sister planet is boiling hot; with a surface temperature of around 464 °C (Nasa.gov). Like Venus, the Earth also has a greenhouse effect due to its carbon dioxide and water vapour. A little greenhouse is a good thing. Like Venus the Earth also has about 90 atmospheres of carbon dioxide but it resides in the crust as limestone and other carbonates, not in the atmosphere. If the temperature of the Earth were to increase slightly (through climate forcing) it could drive some of the CO2 out of the surface rocks, generating a stronger greenhouse effect, which would in turn heat the surface further and there would be the possibility of a run-away greenhouse effect to very high temperatures. This is what is thought to have happened in the early history of Venus, accredited to its proximity to the Sun. The surface environment of Venus is a warning: something disastrous can happen to a planet rather like our own.
But we have also been disturbing the climate in the opposite sense. Throughout history human beings have been burning and cutting down forests and encouraging domestic animals to graze on and destroy grasslands. But forests are darker than grasslands, and grasslands are darker than deserts. As a consequence, the amount of sunlight that is absorbed by the ground has been declining, and by changes in the land use we are lowering the surface temperature of our planet. Might this cooling increase the size of the polar ice cap, which because it is bright will reflect still more sunlight from the Earth, further cooling the planet driving a runaway albedo effect? This is the case on Mars, a planet dominated by two large polar ice caps and where surface temperatures have been recorded to be as low as -143°C.
Can the Earth possibly change its role in the Goldilocks story? We don’t know, but it is certainly a possibility. In the words of Carl Sagan; ”The Earth is a tiny and fragile world. It needs to be cherished”.
Oceans cover approximately 71% of Earth’s surface. The ocean and its ecosystems are a frequently overlooked asset to humans. The most obvious benefit is that it is an easily accessible food source. Australia has set a new precedent by creating the largest marine reserve network in the world in an effort to protect the approximately 4,000 fishes sustained in their portion of the global ocean by increasing the number of reserves in the network from 27 to 60 and increasing the square kilometers from 800,000 to 3.1 million. Australian officials believe that this will guard the environment by enacting such protections as restricting fishing and oil and gas exploration. By keeping 1/3 of their territorial waters as a reserve, Australian officials suggest that these measures will prevent overfishing and guarantee future fish stocks ensuring food security. All of mankind would benefit if other countries would follow suit and enact similar measures. Planning ahead for the future generations of humans and other species is a necessary expense!
As posted on National Snow and Ice Data Center.
Ice extent in the Arctic was below average during November. There was substantially less ice than average in the northern Barents Sea, likely due to an influx of warm ocean waters and the persistence of a strong positive Arctic Oscillation…