Editing Climate variability and change (section)

==== The Holocene ====
[[File:Holocene Temperature Variations.png|right|thumb|upright=1.35|Temperature change over the past 12 000 years, from various sources. The thick black curve is an average.]]
The [[Holocene]] is characterized by a long-term cooling starting after the [[Holocene climatic optimum|Holocene Optimum]], when temperatures were probably only just below current temperatures (second decade of the 21st century),<ref>{{Cite journal|last1=Kaufman|first1=Darrell|last2=McKay|first2=Nicholas|last3=Routson|first3=Cody|last4=Erb|first4=Michael|last5=Dätwyler|first5=Christoph|last6=Sommer|first6=Philipp S.|last7=Heiri|first7=Oliver|last8=Davis|first8=Basil|date=30 June 2020|title=Holocene global mean surface temperature, a multi-method reconstruction approach|journal=Scientific Data|language=en|volume=7|issue=1|page=201|doi=10.1038/s41597-020-0530-7|pmid=32606396|pmc=7327079|bibcode=2020NatSD...7..201K|issn=2052-4463|doi-access=free}}</ref> and a strong [[African Monsoon]] created grassland conditions in the [[Sahara]] during the [[Neolithic Subpluvial]]. Since that time, several [[stadial|cooling events]] have occurred, including:

*the [[Piora Oscillation]]
*the [[Middle Bronze Age Cold Epoch]]
*the [[Iron Age Cold Epoch]]
*the [[Little Ice Age]]
*the phase of cooling c. 1940–1970, which led to [[global cooling]] hypothesis

In contrast, several warm periods have also taken place, and they include but are not limited to:
*a warm period during the apex of the [[Minoan civilization]]
*the [[Roman Warm Period]]
*the [[Medieval Warm Period]]
*[[Modern Warming|Modern warming]] during the 20th century

Certain effects have occurred during these cycles. For example, during the Medieval Warm Period, the [[American Midwest]] was in drought, including the [[Sand Hills (Nebraska)|Sand Hills of Nebraska]] which were active [[sand dune]]s. The [[black death]] plague of ''[[Yersinia pestis]]'' also occurred during Medieval temperature fluctuations, and may be related to changing climates.

Solar activity may have contributed to part of the modern warming that peaked in the 1930s. However, solar cycles fail to account for warming observed since the 1980s to the present day.{{Citation needed|date=September 2016}} Events such as the opening of the [[Northwest Passage]] and recent record low ice minima of the modern [[Arctic shrinkage]] have not taken place for at least several centuries, as early explorers were all unable to make an Arctic crossing, even in summer. Shifts in [[biome]]s and habitat ranges are also unprecedented, occurring at rates that do not coincide with known climate oscillations {{Citation needed|date=September 2016}}.