Thin section of an ice core from Antarctica. Behind the day-glo radar maps and adorably abstract sun and cloud icons are vast amounts of data feeding atmospheric models that inform not only how we dress for the day, but how we prepare for droughts and superstorms. The climate archive gets wilder and dirtier the deeper you go. Ice cores, boreholes, sediments, pollens, tree rings, corals, and other samples of the geologic field become documents. Weather data flow through neural nets and populate massive data centers, but they also reside in refrigerators and polystyrene tubes. And the climate archive like most archives gets wilder and dirtier the deeper you go. To survey the past years or so, climate researchers can use instrument readings from ships and weather stations, but to understand global patterns across deep time, they must turn to proxies: Species collections, core samples, and medieval manuscripts can all help researchers understand the changing climate, but they are subject to widely varying protocols of collection, preservation, and access. Specimen cases at the Museum of Practical Geology, London, in
Climate Data Information
Ice Core An ice core is a cylinder-shaped sample of ice drilled from a glacier. Ice core records provide the most direct and detailed way to investigate past climate and atmospheric conditions. Snowfall that collects on glaciers each year captures atmospheric concentrations of dust, sea-salts, ash, gas bubbles and human pollutants.
They were also consistent with Greenland ice-cores, other Antarctic ice-cores, dated volcanic records, deep sea cores, and paleoclimatic evidence. Results While unable to provide specific dates (within a millenia), the analysis show definate evidence of the the last two ice ages.
The ice sheet is currently stable due to its buttressing ice shelves and local regions where the bathymetry opposes the general trend. The figure panel opposite shows the Pine Island Glacier and Twaites ice streams, which are grounded well below sea level and drain a large proportion of West Antarctica. Their accumulation areas flow from the Transantarctic Mountains and out into the Amundsen Sea.
Here, you can clearly see the difference between the West and East Antarctic ice sheets. They are separated by the m high Transantarctic Mountains. The cross section shows how the West Antarctic Ice Sheet is grounded below sea level. The figures below show how, firstly, the West Antarctic Ice Sheet is grounded below sea level, and that both the West and East Antarctic Ice sheet have water lakes and channels at their base; secondly, bedrock topography of Antarctica; thirdly, ice streams of Antarctica, and fourthly, what the Antarctic continent would look like if all the ice were to be removed.
Note how West Antarctica becomes a series of islands. Isostatically corrected Antarctic continent with the ice removed. Global Warming Art Project. The profile shows that most of the West Antarctic ice sheet is grounded below sea level which makes it sensitive to sea level rise. If the contact of the ice to the bottom rocks is lost seaward of the grounding line, the ice sheet becomes significantly thinner some m , forming a shelf ice.
By Hannes Grobe
The Big Data of Ice, Rocks, Soils, and Sediments
How do ice cores work? Current period is at right. From bottom to top: Milankovitch cycles connected to 18O. From top to bottom: Ice sheets have one particularly special property.
Quaternary: Quaternary, in the geologic history of Earth, a unit of time within the Cenozoic Era, beginning 2,, years ago and continuing to the present day. The Quaternary has been characterized by several periods of glaciation (the “ice ages” of common lore), when ice sheets many kilometres thick have.
Pollen and plant DNA buried in the seafloor offshore of Greenland also suggest the island once had tundra and patchy forest, similar to today’s high Arctic. The new findings hint that at Summit, the tundra landscape was open to the sky for , years to 1 million years before ice covered it. See Greenland’s Ancient Landscape ] “There was a really stable landscape on Greenland before the ice sheet came,” said lead study author Paul Bierman, a geomorphologist at the University of Vermont.
If the soil under Summit has been buried for 2. The 10, foot-long 3, meters GISP2 ice core records more than , years of past climate history, but until now, no one had examined the dirt in the ice at the bottom of the drill hole. It’s the evolution of science — you’re always coming up with new hypotheses to test,” he said.
Piece of the GISP2 ice core showing silt and sand embedded in ice. Soon after this picture was taken, the ice was crushed in the University of Vermont clean lab and the sediment was isolated for analysis. Bierman and his co-authors teased out the sediment locked in the frozen ice, and deciphered its history with a well-established geochemical technique called beryllium dating.
They formed three settlements—known as the Eastern Settlement , the Western Settlement and the Middle Settlement —on fjords near the southwestern-most tip of the island. Norse Greenlanders submitted to Norwegian rule in the 13th century under the Kingdom of Norway — Later the Kingdom of Norway entered into a personal union with Denmark in , and from was a part of the Kalmar Union.
Yes, global warming is real and most of the recent increases in temperature are directly the result of human actions. However, a number of predictions publicized in the media present unrealistic scenarios of doom and gloom.
Are we headed for a new ice age? By Phil Plait June 17, 6: Can this mean the Earth itself will literally cool off, slipping into an ice age? The answer — spoiler alert! And if you have the attention span of an E. One in particular was Caspar Ammann , who was very helpful in explaining the solar connection with the Little Ice Age to me.
The strength and complexity of the solar field governs a lot of the surface activity, including sunspots , solar flares , prominences , and coronal mass ejections. But scientists studying the Sun have seen three independent lines of reasoning indicating that the next rise to the solar peak, in or so, may be delayed or even not occur at all. I wrote about this in an earlier post , so you can get the details there. Doug is an acquaintance of mine; I interviewed him for an episode of “Bad Universe” about solar storms] , has written a document calling the findings into question.
At this point you may be asking, so what? If the Sun has fewer sunspots and no flares, what difference does that make here on Earth?
From this was recovered the deepest ice core record to date. Comparative data between these two deep cores have allowed scientists to develop an ice core-derived paleoenvironmental record dating back greater than , years BP BP means “before present” and “BP” is defined as In other words, the ice has been confirmed to be as old as the collective measurements indicate. These data alone destroy the core doctrine of the theory of Young Earth Creationism that the Earth is only about 6, years old.
An ice core is a core sample that is typically removed from an ice sheet or a high mountain the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper, and an ice core contains ice formed over a range of years.
This age is obtained from radiometric dating and is assumed by evolutionists to provide a sufficiently long time-frame for Darwinian evolution. And OE Christians theistic evolutionists see no problem with this dating whilst still accepting biblical creation, see Radiometric Dating – A Christian Perspective. This is the crucial point: Some claim Genesis in particular, and the Bible in general looks mythical from this standpoint. A full discussion of the topic must therefore include the current scientific challenge to the OE concept.
This challenge is mainly headed by Creationism which teaches a young-earth YE theory. A young earth is considered to be typically just 6, years old since this fits the creation account and some dating deductions from Genesis. The crucial point here is: Accepted Dating Methods Here we outline some dating methods , both absolute and relative, that are widely accepted and used by the scientific community.
Marine ice sheet instability
These brown layers consist of material originating from volcanic eruptions. One of the most distinct ash layers in the Greenland ice cores is seen to the right of this 55 cm long piece of an ice core. It is the 55, year old ash layer Z2, which is believed to originate from an enormous eruption in Iceland. The same ash layers is also found in many sediment cores from the North Atlantic region, hence the layer is an important reference horizon that is used to link ice cores with other sediment cores from other archives of past climate.
One of the most distinct ash layers in the Greenland ice cores is seen to the right of this 55 cm long piece of an ice core. It is the 55, year old ash layer Z2, which is believed to originate from an enormous eruption in Iceland.
Throughout most of what is commonly called the Little Ice Age — the mean solar activity was quite low, but positive fluctuations occurred about —90 and — However, these regional temperature declines rarely occurred at the same time. Cooler episodes also materialized in the Southern Hemisphere, initiating the advance of glaciers in Patagonia and New Zealand, but these episodes did not coincide with those occurring in the Northern Hemisphere.
Meanwhile, temperatures of other regions of the world, such as eastern China and the Andes, remained relatively stable during the Little Ice Age. Still other regions experienced extended periods of drought , increased precipitation, or extreme swings in moisture. Many areas of northern Europe , for instance, were subjected to several years of long winters and short, wet summers , whereas parts of southern Europe endured droughts and season-long periods of heavy rainfall.
For these reasons the Little Ice Age, though synonymous with cold temperatures, can also be characterized broadly as a period when there was an increase in temperature and precipitation variability across many parts of the globe.
How are ice cores dated?
Originally published in Journal of Creation 15, no 3 December Abstract Ice cores found at the poles are thought to show , years of annual snow accumulation. Yet a plane squadron downed in Greenland was found buried in feet of ice that had accumulated in less than 50 years!
The Ice Age: Causes and Consequences. The Ice Age has been a longstanding problem for uniformitarian thinking, with many unsolved mysteries. No mere tweaking of today’s climate conditions would cause such a catastrophe.
I was wondering how ice cores are dated accurately. I know Carbon 14 is one method, but some ice cores go back hundreds of thousands of years. Would other isotopes with longer half-lives be more accurate? Also, how much does it cost to date the core? How are samples acquired without destroying the ice? I imagine keeping the ice intact as much as possible would be extremely valuable.
Some of the answers to these questions are available on the Ice Core Basics page.
How are ice cores dated?
Daly “Whan that Aprille with his shoures soote – The droughte of March hath perced to the roote, And bathed every veyne in swich licour Of which vertu ungendred is the flour;” – from The Canterbury Tales, by Geoffrey Chaucer, “Our years are turned upside down; our summers are no summers; our harvests are no harvests! In their previous report , the IPCC illustrated their, then, understanding of how global climate had changed, not just during the previous 95 years, but also the past 1, years.
In so doing they presented this graph Fig 1. Historical records from all over Europe, and Greenland attest to the reality of both events, and their profound impact on human society. For example, the colonisation of Greenland by the Vikings early in the millennium was only possible because of the medieval warmth.
Do you know if ice core dating is accurate. I heard that Antarctica had ice rings like tree rings that go back 50, years undisturbed by a flood. If it is challenged do you know on what basis. These seasonal layers can be counted. An ice core of over 2km in length has been drilled and carefully.
View images by clicking on link or reduced image: Each image opens into a new window. These primitive, medium sized apes lived in rain forests between 18 and 22 million years ago. This species and others such as Dryopithecus existed before the hominid line diverged on the path to humans. This lineage ancestral gibbons is believed to have diverged from the great ape and human lineages between 17 and 25 Mya Avers, Oreopithecus ‘s hand closely matches the pattern of early hominids, with a grasping capability including firm pad-to-pad precision gripping that apes are unable to perform presumably as a response to similar functional demands to hominids Moya-Sola et al, Bipedal activities made up a significant part of the positional behavior of this primate Kohler and Moya-Sola, Gorilla and human DNA only differs by 2.
Our DNA differs by only 1. The two species of Pan, the chimpanzee, P. The human ancestral line must have arisen between 5 and 8 million years ago. However, with the many species to be found, the exact sequence of species leading to humanity, has not yet been established. Morphological differences, such as in the pelvis, supports making Neanderthals a separate species, Homo neanderthalensis.