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Weren’t temperatures warmer than today during the “Medieval Warm Period”?

This is one of a number of popular myths regarding temperature variations in past centuries. At hemispheric or global scales, surface temperatures are believed to have followed the “Hockey Stick” pattern, characterized by a long-term cooling trend from the so-called “Medieval Warm Period” (broadly speaking, the 10th-mid 14th centuries) through the “Little Ice Age” (broadly speaking, the mid 15th-19th centuries), followed by a rapid warming during the 20th century that culminates in anomalous late 20th century warmth. The late 20th century warmth, at hemispheric or global scales, appears, from a number of recent peer-reviewed studies, to exceed the peak warmth of the “Medieval Warm Period”. Claims that global average temperatures during Medieval times were warmer than present-day are based on a number of false premises that a) confuse past evidence of drought/precipitation with temperature evidence, b) fail to disinguish regional from global-scale temperature variations, and c) use the entire “20th century” to describe “modern” conditions , fail to differentiate between relatively cool early 20th century conditions and the anomalously warm late 20th century conditions.

9 comments on this post.
  1. super-structure » 25 Reasons Why You Should Understand Neil Boortz Is Wrong | Jason Coleman:

    [...] Medieval Warm Period. Yet another popular myth. The short answer: it’s global warming, not just European warming. [...]

  2. Jeff McIntire-Strasburg » Blog Archive » Green Myth-Busting: Greenland was Once Green:

    [...] from NOAA. RealClimate, the blog for anyone interested in hardcore climate science, also presents a number of reasons why the perception skeptics have about the Medieval Warm Period are likely [...]

  3. Understanding Global Warming « Understanding Global Warming:

    [...] and had relatively little impact on the global averages. Dr. Michael Mann addresses this here (and for an example of a contrarian tactic that can make it appear otherwise, or that the current [...]

  4. Understanding Global Warming:

    [...] and had relatively little impact on the global averages. Dr. Michael Mann addresses this here (and for an example of a contrarian tactic that can make it appear otherwise, or that the current [...]

  5. Hypography Science Forums - Co2 Acquittal:

    [...] by mitigating our impact. And I know you like this place so yes, I did look here ==> RealClimate Here is an interesting article. [...]

  6. Earth: The Climate Wars - Wildlife and Environment Forums:

    [...] of the little ice age and medieval warm period and many other discussions of climate change: RealClimate To summarise the ideas very simplistically I think this is what they say – the little ice age and [...]

  7. Understanding the Basics of Global Holocene Climate Change « Understanding Global Warming:

    [...] magnitude of medieval warmth was weaker than that of today. Dr. Michael Mann also addresses this here (and for an example of a contrarian tactic that makes it appear otherwise, or that the current [...]

  8. Understanding Global Warming:

    [...] magnitude of medieval warmth was weaker than that of today. Dr. Michael Mann also addresses this here (and for an example of a contrarian tactic that makes it appear otherwise, or that the current [...]

  9. Ben’s Blog » Blog Archive » Head to head with a Cardinal:

    [...] qualified in a way that I, and the good Cardinal, are not. (The medieval warm period wasn’t warmer. Warming didn’t stop in 1998.) But most appalling to me was this childish attempt to use his [...]