Sentences with word «silurian»

The most unusual features of the Silurian that distinguish it from the present - day physical environment relate to conditions of low continental elevations combined with a much higher global stand in sea level.

Atmospheric circulation patterns interpreted for an early Silurian summer in the Northern Hemisphere indicate high pressure over the polar ocean with a zone of low pressure around 60 ° N latitude.

For example, glaciers developed for a brief period (between 1 million and 10 million years) during the late Ordovician and early Silurian, in the middle of the early Paleozoic greenhouse phase (542 million to 350 million years ago).

Vascular plants began to colonize coastal lowlands during the Silurian Period, whereas continental interiors remained essentially barren of life.

During most of the Silurian Period, the vast Panthalassic Ocean covered the northern polar regions, the supercontinent of Gondwana stretched over the southern polar region, and a ring of at least six continents spanned the Equator and middle latitudes.

This somewhat migratory zone was the Silurian intertropical convergence zone (ITCZ), where the convergence of Northern and Southern Hemispheric trade winds caused the warm tropical air to rise, which in turn produced regular cloud cover and precipitation.

Broad - scale Silurian climatic conditions can be inferred by determining the positions and orientations of the paleocontinents and assuming that atmospheric circulation functioned according to the same basic principles during Silurian times as it does today.

The approximate orientations and locations of Silurian continents can be reconstructed using a combination of paleomagnetic, paleoclimatic, and biogeographic data.

Instead readers get The Silurian Hypothesis, a weaker Atlantic overturning circulation, Harde Times, Alsup asks for answers (and gets none), Rideau Canal Skateway, then More ice - out and skating day data sets.

So the isotopic spikes we do see in the geologic record may not be spiky enough to fit the Silurian hypothesis's bill.

We know something else about sustained releases of GHGs: - Cretaceous — Paleogene extinction - Triassic — Jurassic extinction - End Permian - Late Devonian - Ordovician — Silurian extinction events

«some authors propose a 10 Ma long North African glaciation that started much earlier in the Ordovician (Ghienne, 2003) and lasted well into the Silurian (Grahn and Caputo, 1992; Caputo, 1998; Pope and Read, 1998; Crowell, 1999; Saltzman and Young, 2005).

The federal Bureau of Land Management describes the Silurian Valley as an «undisturbed, irreplaceable, historic scenic landscape.»

In what they call the Silurian hypothesis — a reference not to the geological period long before the first creatures crawled from the sea onto the empty continents, but to a 1970 episode of the British television serial Dr Who — they turn to the only testbed available to contemporary Earthlings: the evidence of the Anthropocene, the geologists» name for a new era that could be considered to have commenced with the Industrial Revolution.

Therefore... in the Old Silurian Period the Mississippi River was upward of one million three hundred thousand miles long... seven hundred and forty - two years from now the Mississippi will be only a mile and three - quarters long.

«Our results indicate that tropical sea surface temperatures were significantly higher than today during the Early Silurian period (443 — 423 Myr ago), when carbon dioxide concentrations are thought to have been relatively high, and were broadly similar to today during the Late Carboniferous period (314 — 300 Myr ago), when carbon dioxide concentrations are thought to have been similar to the present - day value.

CO2 was higher in the past «The killer proof that CO2 does not drive climate is to be found during the Ordovician - Silurian and the Jurassic - Cretaceous periods when CO2 levels were greater than 4000 ppmv (parts per million by volume) and about 2000 ppmv respectively.

In what they deem the «Silurian Hypothesis,» Frank and Schmidt define a civilization by its energy use.

I doubt a civilisation with language and relics of machines could have occurred as early as the Silurian ~ 400 mya.

to say, we aren't proposing any such occurrence (not least because the Silurian period is too early for the development of complex life on land).

Does The Silurian Hypothesis enhance the credibility and believably of the author / s in regard to their expertise in climate science?

Does the publication of The Silurian Hypothesis open up a new opportunity for powerful forces to further undermine the credibility of climate science and climate scientists?

Does The Silurian Hypothesis help to educate or inform the public or journalists about the overwhelming evidence of climate change, it's causes and solutions?

Therefore, any calm person, who is not blind or idiotic, can see that in the Old Oolitic Silurian Period, just a million years ago next November, the Lower Mississippi River was upwards of one million three hundred thousand miles long, and stuck out over the Gulf of Mexico like a fishing - rod.

The Silurian Hypothesis?

Does The Silurian Hypothesis enhance the credibility of others who are directly connected to the author / s such as Stefan's recent article here and enhance Michael Mann's already tarnished reputation in the public sphere any?

nigelj, «The silurian short story and related research paper was obviously intended to 1) be thought provoking»

The astrobiology article on the Silurian hypothesis makes a very good accompaniment to the story — or perhaps the aricle is the main course, and the story is the dessert!

Is The Silurian Hypothesis useful?

The Silurian Hypothesis (preprint) is the idea if industrial civilization had arisen on Earth prior to the existence of hominids, what traces would be left that could be detectable now?

Leaving aside loose talk of dinosaurs and the generalized use of «Silurian'to refer to any prehistoric, industrialized civilization, let us for a moment examine the original Silurian in its fully developed phase:

The silurian short story and related research paper was obviously intended to 1) be thought provoking 2) draw the general public into scientific issues and 3) provide some light relief from the serious and sometimes depressing issue of climate change.

What / Why: «Framed by geologic time, the images in an ongoing abstract, self - portrait series by Kathleen Gerdon Archer are divided into 6 sections; the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian.

Theres «another» doctor who level too... the tardis point in middle earth takes to you the silurian spaceship in «Dinosaurs on a spaceship»... including a scene of 11 riding a triceretops

Rather than the Cambrian (541 Ma) as previously thought, they propose that this happened much later during the Silurian (~ 420 Ma).

A tour of life over geologic time and evolution as evidenced by the fossil record: Precambrian Fossils I Cambrian Fossils I Ordovician Fossils I Silurian Fossils I Devonian Fossils Carboniferous Fossils I Permian Fossils I Triassic Fossils I Jurassic Fossils I Cretaceous Fossils I Tertiary Fossils

A minor ice age, the Andean - Saharan, occurred from 460 to 430 million years ago, during the Late Ordovician and the Silurian period.

One wild idea the Silurian hypothesis raises is that the end of one civilization could sow the seeds for another.

Will editorials and social media comments labeling The Silurian Hypothesis as a crackpot paper written by a crackpot climate scientist help or diminish the hard work of all climate scientists and many others?

The Silurian hypothesis is interesting and really worth discussing, not just as a thought experiment but also because it gets us to think a bit more about our own rather wonderful planet and climate system and how much we really understand about it.

Scientists put the Silurian hypothesis to the test, to see if humans were the first major civilization on Earth.

The description of the new Silurian species was part of a wider investigation into this group of fossils, including several new Jurassic specimens.

In a paper just published in Nature Communications, they present evidence that malformed fossil remains of marine plankton from the late Silurian (415 million years ago) contain highly elevated concentrations of heavy metals, such as iron, lead, and arsenic.

Both of these Silurian microfossils are from the A1 - 61 well in Libya and are about 415 Ma old.

Several Palaeozoic mass extinction events during the Ordovician and Silurian periods (ca. 485 to 420 to million years ago) shaped the evolution of life on our planet.

But as the ecosystem recovered after the freeze, it expanded, with land plants becoming common over the course of the Silurian period.

The Paleozoic includes six geologic periods; from oldest to youngest — the Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian.

In what they deem the «Silurian Hypothesis,» Frank and Schmidt define a civilization by its energy use.

The fossil record includes the Stromatolites, colonies of prokaryotic bacteria, that range in age going back to about 3 billion years, the Ediacara fossils from South Australia, widely regarded as among the earliest multi-celled organisms, the Cambrian species of the Burgess shale in Canada (circa — 450 million years ago) the giant scorpions of the Silurian Period, the giant, wingless insects of the Devonian period, the insects, amphibians, reptiles, fishes, clams, crustaceans of the Carboniferous Period, the many precursors to the dinosaurs, the 700 odd known species of dinosaurs themselves, the subsequent dominant mammals, including the saber tooth tiger, the mammoths and hairy rhinoceros of North America and Asia, the fossils of early man in Africa and the Neanderthals of Europe.

Flipping through the pages of a beautifully produced study of fossil invertebrates from Princeton University Press, I came across a Silurian trilobite that might have provided a breastplate for an archaic pre-Lilliputian warrior.