Catherine Ritz

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This was the peak of manned observation in Antarctica, and since then the number of staffed stations has declined, though this is offset by an increasing number of automatic stations. A further boost to the observing network has taken place in the International Polar Year of — Most manned stations are built on ice-free ground at coastal sites, primarily so that stores can easily be transported ashore and to simplify construction. The weather recorded at these sites is not a true representation of the continent as a whole, as the coastal areas are much milder than the interior due to the moderating influence of the sea and, at the more local scale, the surrounding rock. Automatic stations are much more widely spread across the continent and give a broader picture of the meteorology. Surface temperature, humidity, solar radiation, atmospheric pressure, wind speed and direction are largely measured by automated instruments, but an observer is needed to estimate visibility and the amount, type and height of clouds, although automatic instruments are being introduced to deal with these parameters. The observer also needs to monitor the weather: Traditional weather observing on the polar plateau brings additional problems, with the combination of very low temperature and high altitude.

No document with DOI “10.1.1.686.1175”

Van Liefferinge and Pattyn Phys. Scientists have now identified regions in Antarctica they say could store information about Earth’s climate and greenhouse gases extending as far back as 1. By studying the past climate , scientists can understand better how temperature responds to changes in greenhouse-gas concentrations in the atmosphere. This, in turn, allows them to make better predictions about how climate will change in the future.

A Review of Antarctic Surface Snow Isotopic Composition: Observations, Atmospheric Circulation, and Isotopic Modeling* ing methods (Parrenin et al. ). The dating of deep ice cores itself, when constrained by age markers, can central Antarctic ice cores stable isotope records also suggests a small magnitude (°C) of common cen-.

Member beliefs What most LDS have been taught in church and believe as truth The leaders of the church, as well as gospel doctrine teachers the world over, have taught that many Biblical events and beliefs that people have had for centuries are indeed true, historical events. Joseph Smith and other prophets have made statements that indicated that certain Biblical events were indeed historical and not merely parables. Many of these Biblical traditions were believed as literal events by most of the general population in the s as well.

Global Flood of Noah. Adam and Eve were the first humans. Dinosaurs were never alive on this earth, because there was no death before Adam.

Ice core basics

There are stations covering different time windows having very close patterns of temperatures. Homogenization is supposed to be used to account for upwards biases such as Urban Heat Island, not to introduce upwards biases. The longest of the Australian temperature records that were considered the most reliable by Bureau of Meteorology on February BOM are still available as raw temperatures in the climate data online section and consistently show no warming and no increased extreme events within the limit of accuracy of measurements.

It can be expected that the periodicity of G7, lasting years so far, will persist also for the foreseeable future. It predicts a temperature drop from present to AD , a slight rise from to , and a further drop from AD to The coldest SSTs are detected between and CE, on Iberia during the well-known Little Ice Age LIA Bradley and Jones, , with the most intense cooling episodes related with other solar minima events, and major volcanic forcing and separated by intervals of relative warmth e.

Precise interpolar phasing of abrupt climate change during the last ice age Authors: WAIS Divide Project Members Antarctic ice cores have so far precluded methane-based synchron- Antarctic breakpoints and Greenland transitions within a dating uncertainty of .

The arrow shows a typical glacial—interglacial range, and the figure shows that the rapid events span a large part of that range. The figure is annotated to show the timing of some of the important climate features that are mentioned in the text and that are also manifested in changes in CH4 concentration: The causes of the observed glacial—interglacial and D—O CH4 changes Most analyses of the ice core data have tended to assume that changes in wetland emissions are responsible, with much of the discussion concentrating on apportioning those changes between the tropical and northern wetlands e.

However, changes in the concentrations of sinks may also be important and the possible influence of other sources marine hydrates, biomass burning and vegetation must also be considered. There are a number of tools available for distinguishing different causes of the observed changes in atmospheric composition. Firstly, isotopic data 13C, D, and eventually 14C can provide constraints on the relative importance of different sources as already discussed for the last years. Secondly, because the lifetime of methane less than a decade is not many times larger than the interhemispheric mixing time, we expect latitudinal inhomogeneity in the distribution of sources and sinks to lead to significant interhemispheric differences in concentration.

Thus, by measuring the difference between Greenland and Antarctic concentrations, we can estimate the latitude of sources assuming a uniform sink. As models of the Earth system become more complex, it has become possible to attempt bottom-up modelling in which climate changes drive changes in vegetation and emissions. Such exercises can test hypotheses about the influence of climate on sources and sinks to see whether they fit the data constraints. Finally, we can search for other constraints on the sinks of methane.

Pleistocene Epoch

Dyson, The magnitude of this negative feed-back effect of atmospheric CO2 upon itself depends on many ecological interactions which have yet to be disentangled. The effect could be negligibly small, or it could be as large as 3 x tons of carbon per yr. In summary, there is insufficient evidence to decide whether the carbon content of the biosphere has decreased, increased or remained stationary in response to the manifold human activities of recent decades.

There exists a huge literature attempting to assess or to prognosticate the effects of the increasing atmospheric CO2 on the climate of the earth. Such attempts are useful and necessary, hut they run into formidable technical difficulties.

The most recent ice core time scale for Antarctica is the Antarctic Ice Core Chronology (AICC) that applies to several deep Antarctic ice cores (Bazin et al., ; Veres et al., ). For the last 60, years, AICC is synchronized to the Greenland ice cores through their global gas concentration records and through bipolar.

References Overview Ice cores collected in polar or other glaciated regions offer unique records of past climate. Ice cores also contain records of local and distant volcanism, and have been widely used to develop volcanic climate forcing time series in climate simulations and models Crowley, ; Oppenheimer, ; Robock, ; Robock and Free, ; Sato et al. The interpretation of the global climate record in ice cores is critically dependent on correct chronology or correct correlations of events detected in different environmental records.

For some types of ice cores, particularly for the upper parts of cores in areas of high snow accumulation, the chronology of a core can be determined by counting a continuous record of annual layers e. However, for many ice cores, particularly in the interior of Antarctica, the accumulation of snow is too low for annual layers to be detectable Steig et al. In this case, other techniques must be used to determine the chronology of the cored ice. These techniques include modeling of annual layer thickness versus depth e.

However, as pointed out by Lemieux-Dudon et al. In contrast, volcanic ash tephra layers in ice cores, although much less common than the volcanic sulfate layers, typically display a chemical fingerprint characteristic of a given eruption, and therefore can provide less ambiguous time-stratigraphic marker layers. If the volcanic layer can be unambiguously chemically correlated to a dated volcanic event, this provides a date, albeit one with typically a high analytical error, for the horizon in the core where the layer is found.

Alternatively, if the age of the event is not well known, the chemical composition of the layer can allow direct correlation between stratigraphic horizons from multiple cores in which the layer is found. This type of cross-correlation provides a high-precision chronological link between cores, because tephra deposition typically takes place in a time span of several weeks to months. When a tephra layer is deposited near the volcanic source, the layer can be thick and coarse, but the further the tephra is from source, or the further from the main depositional axis of the ash cloud, the finer and sparser the deposit becomes.

The Best CMS

Identification[ edit ] A rapid cooling around BC was first identified by Swiss botanist Heinrich Zoller in , who named the event Misox oscillation for the Val Mesolcina. Cooling event[ edit ] The event may have been caused by a large meltwater pulse from the final collapse of the Laurentide ice sheet of northeastern North America, most likely when the glacial lakes Ojibway and Agassiz suddenly drained into the North Atlantic Ocean.

The melt-water pulse may have affected the North Atlantic thermohaline circulation , reducing northward heat transport in the Atlantic and causing significant North Atlantic cooling. In Greenland, the event started at BP, and the cooling was 3.

The high dating accuracy allowed placing the large bi‐hemispheric deposition event ascribed to the eruption of Kuwae in Vanuatu (previously thought to be / C.E. and used as a tie‐point in ice core dating) into the year / C.E.

The strict definition of Heinrich events is the climatic event causing the IRD layer observed in marine sediment cores from the North Atlantic: By extension, the name Heinrich events can also refer to the associated climatic anomalies registered at other places around the globe, at approximately the same time periods. The events are rapid: Heinrich events are clearly observed in many North Atlantic marine sediment cores covering the last glacial period; the lower resolution of the sedimentary record before this point makes it more difficult to deduce whether they occurred during other glacial periods in the Earth’s history.

Heinrich events appear related to some, but not all, of the cold periods preceding the rapid warming events known as Dansgaard-Oeschger D-O events, which are best recorded in the NGRIP Greenland ice core. However, difficulties in synchronising marine sediment cores and Greenland ice cores to the same time scale cast aspersions on the accuracy of that statement. The larger size fractions cannot be transported by ocean currents, and are thus interpreted as having been carried by icebergs or sea ice which broke off glaciers or ice shelves, and dumped debris onto the sea floor as the icebergs melted.

Geochemical analyses of the IRD can provide information about the origin of these debris: The signature of the events in sediment cores varies considerably with distance from the source region. During Heinrich events, huge volumes of fresh water flow into the ocean.

Bad Astronomy

The study involves looking at deuterium levels in the ice down to a depth of m, corresponding with an age of around , years. This is the longest complete record of polar ice, and encompasses 11 distinct glaciation periods. The data gathered in this study was used to reconstruct a temperature record for the period. This was done by plugging this data, along with deep-sea oxygen isotope data, into an atmospheric General Circulation Model.

Recent efforts to acquire deep cores through the West Antarctic Ice Sheet (Exhibit 42) seek to use exceptionally high-resolution cores for comparison with Greenland records to learn where climate changes start and how rapidly they spread important information in learning to predict them.

Human timeline and Nature timeline In Pierre Martel — , an engineer and geographer living in Geneva , visited the valley of Chamonix in the Alps of Savoy. He reported that the inhabitants of that valley attributed the dispersal of erratic boulders to the glaciers, saying that they had once extended much farther. In the carpenter and chamois hunter Jean-Pierre Perraudin — explained erratic boulders in the Val de Bagnes in the Swiss canton of Valais as being due to glaciers previously extending further.

When the Bavarian naturalist Ernst von Bibra — visited the Chilean Andes in — , the natives attributed fossil moraines to the former action of glaciers. From the middle of the 18th century, some discussed ice as a means of transport. The Swedish mining expert Daniel Tilas — was, in , the first person to suggest drifting sea ice in order to explain the presence of erratic boulders in the Scandinavian and Baltic regions.

He regarded glaciation as a regional phenomenon. In a paper published in , Esmark proposed changes in climate as the cause of those glaciations. He attempted to show that they originated from changes in Earth’s orbit.

* Astronomy

One of these was a series of buoys, each containing thermometers located ten feet above the water and at one foot below the water. The study found that water temperatures increased on average by 0. As of July , no similar study has been conducted on a global basis.

Jan 24,  · An ice core from the eastern Antarctic Peninsula shows warmer temperatures That said, if it is consistent with recorded history, then it would be a powerful correlation. Thanks for the posting! However it should be understood that in the lower part of the Greenland ice-cores the dating uncertainty can be as large as a couple.

Is the Sun driving ozone and changing the climate? In the hunt for clues continues… The central mystery in climate science is the Sun. The direct energy from the 1. Something else is going on with the Sun. These have different effects. Shorter wavelengths UV generate ozone in the stratosphere and penetrate the ocean. But the tiny changes in total sunlight TSI may still be leaving us clues about other things going on with the Sun.

Stephen Wilde has a theory. Plug in your brain, and follow this chain of potential influence: It is long past time to get into those details. Summary of the Stephen Wilde Hypothesis In essence: The Sun affects the ozone layer through changes in UV or charged particles.

Antarctica’s Ice Cores


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