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Also, you're a bit out of your mind here. This chart is in thousands of years...
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A new approach for reconstructing glacier variability based on lake sediments recording input from more than one glacier
ABSTRACT:
We explore the possibility of building a continuous glacier reconstruction by analyzing the integrated sedimentary response of a large (440 km2) glacierized catchment in western Norway, as recorded in the downstream lake Nerfloen (N61°56', E6°52'). A multi-proxy numerical analysis demonstrates that it is possible to distinguish a glacier component in the ~8000-yr-long record, based on distinct changes in grain size, geochemistry, and magnetic composition. Principal Component Analysis (PCA) reveals a strong common signal in the 15 investigated sedimentary parameters, with the first principal component explaining 77% of the total variability. This signal is interpreted to reflect glacier activity in the upstream catchment, an interpretation that is independently tested through a mineral magnetic provenance analysis of catchment samples. Minimum glacier input is indicated between 6700-5700 cal yr BP, probably reflecting a situation when most glaciers in the catchment had melted away, whereas the highest glacier activity is observed around 600 and 200 cal yr BP. During the local Neoglacial interval (~4200 cal yr BP until present), five individual periods of significantly reduced glacier extent are identified at ~3400, 3000-2700, 2100-2000, 1700-1500, and ~900 cal yr BP.
www.pik-potsdam.de...
Abrupt changes in climate, termed Dansgaard-Oeschger and Heinrich events, have punctuated the last glacial period (~100 – 10 kyr ago) but not the Holocene (the past 10 kyr). Here we use an intermediate-complexity climate model to investigate the stability of glacial climate, and we find that only one mode of Atlantic Ocean circulation is stable: a cold mode with deep water formation in the Atlantic Ocean south of Iceland. However, a `warm’ circulation mode similar to the present-day Atlantic Ocean is only marginally unstable, and temporary transitions to this warm mode can easily be triggered. This leads to abrupt warm events in the model which share many characteristics of the observed Dansgaard-Oeschger events. For a large freshwater input (such as a large release of icebergs), the model’s deep water formation is temporarily switched off, causing no strong cooling in Greenland but warming in Antarctica, as is observed for Heinrich events. Our stability analysis provides an explanation why glacial climate is much more variable than Holocene climate.
Gerard Bond et al., “A Pervasive Millennial-Scale Cycle in North Atlantic Holocene and Glacial Climates,”
Abstract
Evidence from North Atlantic deep sea cores reveals that abrupt shifts punctuated what is conventionally thought to have been a relatively stable Holocene climate. During each of these episodes, cool, ice-bearing waters from north of Iceland were advected as far south as the latitude of Britain. At about the same times, the atmospheric circulation above Greenland changed abruptly. Pacings of the Holocene events and of abrupt climate shifts during the last glaciation are statistically the same; together, they make up a series of climate shifts with a cyclicity close to 1470 ± 500 years. The Holocene events, therefore, appear to be the most recent manifestation of a pervasive millennial-scale climate cycle operating independently of the glacial-interglacial climate state. Amplification of the cycle during the last glaciation may have been linked to the North Atlantic's thermohaline circulation.
crimvelvet
reply to post by webedoomed
Also, you're a bit out of your mind here. This chart is in thousands of years...
Of course it is. It shows how incredibly STABLE the Holocene climate has been so you can thank goodness for mankind's interference or what ever the heck has made it so stable. It also shows the climate oscillates WITHOUT any help from mankind and overall we are COOLING.
let me get this straight...he isn't doing anything to stop climate change, but is asking governors and mayors to prepare for the consequences IF it does happen...and all of you are pissed off about that????...
So invest in green businesses?
You are having serious difficulties interpreting the data on the graph....
Temperature and precipitation history of the Arctic
Solar energy reached a summer maximum (9% higher than at present) ~11 ka ago and has been decreasing since then, primarily in response to the precession of the equinoxes. The extra energy elevated early Holocene summer temperatures throughout the Arctic 1-3°C above 20th century averages, enough to completely melt many small glaciers throughout the Arctic, although the Greenland Ice Sheet was only slightly smaller than at present. Early Holocene summer sea ice limits were substantially smaller than their 20th century average, and the flow of Atlantic water into the Arctic Ocean was substantially greater. As summer solar energy decreased in the second half of the Holocene, glaciers re-established or advanced, sea ice expanded...
....The last “interesting” piece of evidence is that the Little Ice Age, occurring in apparent coincidence with the Maunder Minimum, was the coldest period in the entire Holocene post the Younger Dryas fluctuation, and occurred as global temperatures had been gradually decreasing from the Holocene optimum for thousands of years. This large temperature excursion in response to what may have been a relatively minor variation in a primary driver (the Sun) strongly suggests that the Earth is either entering or is already solidly into the bistable regime where sufficiently sustained fluctuations can drive it nonlinearly towards the cold stable state, quite possibly drive it “rapidly” in that direction...
....the Ordovician/Silurian transition, wherein the Earth entered an ice age, relatively rapidly, in spite of having seventeen times the atmospheric CO2 content that it does now when it began, and in spite of sustaining it at ten times the current concentration for the entire period the ice age lasted...."