PingoPingos are intrapermafrost ice-cored hills, high and in diameter. They are typically conical in shape and grow and persist only in permafrost environments, such as the Arctic and subarctic. A pingo is a periglacial landform, which is defined as a non-glacial landform or process linked to colder climates. It is estimated that there are more than 11,000 pingos on Earth. The Tuktoyaktuk peninsula area has the greatest concentration of pingos in the world with a total of 1,350 pingos.
Oldest DryasThe Oldest Dryas is a biostratigraphic subdivision layer corresponding to a relatively abrupt climatic cooling event, or stadial, which occurred during the last glacial retreat. The time period to which the layer corresponds is poorly defined and varies between regions, but it is generally dated as starting at 18.5–17 thousand years (ka) before present (BP) and ending 15–14 ka BP. As with the Younger and Older Dryas events, the stratigraphic layer is marked by abundance of the pollen and other remains of Dryas octopetala, an indicator species that colonizes arctic-alpine regions.
FoothillsFoothills or piedmont are geographically defined as gradual increases in elevation at the base of a mountain range, higher hill range or an upland area. They are a transition zone between plains and low relief hills and the adjacent topographically higher mountains, hills, and uplands. Frequently foothills consist of alluvial fans, coalesced alluvial fans, and dissected plateaus. Foothills primarily border mountains, especially those which are reached through low ridges that increase in size closer and closer to the mountain, but can also border uplands and higher hills.
10th millennium BCThe 10th millennium BC spanned the years 10,000 BC to 9001 BC (c. 12 ka to c. 11 ka). It marks the beginning of the transition from the Palaeolithic to the Neolithic via the interim Mesolithic (Northern Europe and Western Europe) and Epipaleolithic (Levant and Near East) periods, which together form the first part of the Holocene epoch that is generally believed to have begun c. 9700 BC (c. 11.7 ka) and is the current geological epoch.
CavemanThe caveman is a stock character representative of primitive humans in the Paleolithic. The popularization of the type dates to the early 20th century, when Neanderthals were influentially described as "simian" or "ape-like" by Marcellin Boule and Arthur Keith. The term "caveman" has its taxonomic equivalent in the now-obsolete binomial classification of Homo troglodytes (Linnaeus, 1758). Cavemen are typically portrayed as wearing shaggy animal hides, and capable of cave painting like behaviorally modern humans of the last glacial period.
VarveA varve is an annual layer of sediment or sedimentary rock. The word 'varve' derives from the Swedish word varv whose meanings and connotations include 'revolution', 'in layers', and 'circle'. The term first appeared as Hvarfig lera (varved clay) on the first map produced by the Geological Survey of Sweden in 1862. Initially, "varve" referred to each of the separate components comprising a single annual layer in glacial lake sediments, but at the 1910 Geological Congress, the Swedish geologist Gerard De Geer (1858–1943) proposed a new formal definition, where varve means the whole of any annual sedimentary layer.
DeglaciationDeglaciation is the transition from full glacial conditions during ice ages, to warm interglacials, characterized by global warming and sea level rise due to change in continental ice volume. Thus, it refers to the retreat of a glacier, an ice sheet or frozen surface layer, and the resulting exposure of the Earth's surface. The decline of the cryosphere due to ablation can occur on any scale from global to localized to a particular glacier. After the Last Glacial Maximum (ca.
Core sampleA core sample is a cylindrical section of (usually) a naturally-occurring substance. Most core samples are obtained by drilling with special drills into the substance, such as sediment or rock, with a hollow steel tube, called a core drill. The hole made for the core sample is called the "core hole". A variety of core samplers exist to sample different media under different conditions; there is continuing development in the technology. In the coring process, the sample is pushed more or less intact into the tube.
Holocene climatic optimumThe Holocene Climate Optimum (HCO) was a warm period that occurred in the interval roughly 9,500 to 5,500 years ago BP, with a thermal maximum around 8000 years BP. It has also been known by many other names, such as Altithermal, Climatic Optimum, Holocene Megathermal, Holocene Optimum, Holocene Thermal Maximum, Hypsithermal, and Mid-Holocene Warm Period. The warm period was followed by a gradual decline, of about 0.1 to 0.3 °C per millennium, until about two centuries ago.
