| The Holocene is a geological epoch which began approximately 12,000 years ago (about 10,000 BC) and continues to the present. It is part of the Neogene and Quaternary periods and can be considered an interglacial after the last Würm/Wisconsin glacial. It marks the end of the Upper Palaeolithic, the last period of the Stone Age. Human civilization dates almost entirely from within the Holocene. No faunal stages for the Holocene have been defined by paleontologists. Subdivisions usually reflect periods of human technological development such as the Mesolithic, Neolithic, and Bronze Age. However, the time periods referenced by these terms vary with the emergence of those technologies in different parts of the world. Climatically, the Holocene may be divided evenly into the Hypsithermal and Neoglacial periods; the boundary coincides with the start of the Bronze Age in western civilization. A third division has been proposed by some scholars, the Anthropocene, beginning in the mid 18th Century. Whether this is an age within, or follows, the Holocene epoch is a matter of debate. During the period tectonic plate movement of almost 1 km has been recorded and there have been a number of severe volcanic erruptions and earthquakes. A major Tsunami took place on December 26th, 2004. World sea level rose 35m during the early Holocene due to the melting of glaciers and as parts of the northern land mass were freed from ice they rose by 180m. Post-glacial rebound in the Scandinavian region resulted in the formation of the Baltic Sea. This region continues to rise causing occasional weak earthquakes across Northern Europe. A recent retreat of glaciers has been attributed to global warming due to human polution.
Although geographic shifts during the Holocene have been minor, climatic shifts have been relatively large.  The sharp reversal of the Younger Dryas in the northern hemisphere is very clear in the Greenland data around 11,000 BP as are the preceding dips in the southern hemisphere several hundred years earlier. This a reminder that climate trends can be very much regional and it is a mistake to extrapolate medien global data to get a true picture of what is happening and is likely to happen.  After the end of the last glacial, which had lasted about 60,000 years, temperatures rose very quickly before levelling off and peaking at the Holocene Maximum about 7,800 years ago. Since about 4,100 years ago the temperature would seem to have a declining trend which has only been reversed from about 1900. 
The magnitude of change after 1900 is pronounced and dispite a brief reversal in the 1960s the trend has continued upwards. On a graph with a longer time scale the hundred years from 1900 until today would be represented by a vertical line. There is some new evidence that similar very fast rises took place in the past, but the causes are unknown. Only since the 18th Century have we reliable statistics concerning temperature and climate; everything before that contains an element of uncertainty. The one certainty we do have is that we are going through a time of very rapid, geologically speaking, climate change - for whatever reasons.
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