Friday, August 30, 2013

New paper finds another non-hockey-stick in Tibet; temperatures during the Little Ice Age warmer than in 2000

A paper published today in Quaternary Research reconstructs temperatures in Tibet over the past 563 years and finds another non-hockey-stick with temperatures during the Little Ice Age at ~1550 AD warmer than at the end of the record in 2000. The paper adds to the peer-reviewed publications of over 1,200 scientists finding non-hockey-sticks around the globe. The authors find, "The temperature variability in this area may be affected by ENSO, the Pacific Decadal Oscillation and solar activity," [What?, not AGW?!]

Bottom graph shows temperature reconstruction over the past 563 years. Note the Medieval Warming Period was ~1000 years ago and is not shown in this reconstruction. Top graph shows reconstructed temperatures compared to actual observed temperatures.

Early-summer temperature variations over the past 563 yr inferred from tree rings in the Shaluli Mountains, southeastern Tibet Plateau

  • a MOE Key Laboratory of Western China’s Environmental Systems, Collaborative Innovation Centre for Arid Environments and Climate Change, Lanzhou University, Lanzhou 73000, China
  • b State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China

Abstract

We developed a tree-ring chronology (AD 1446–2008) based on 75 cores from 37 Abies squamata Mast. trees from the Shaluli Mountains, southeastern Tibet Plateau, China, using signal-free methods, which are ideally suited to remove or reduce the distortion introduced during traditional standardization. This chronology correlates best with regional temperatures in June–July, which allowed us to develop a June–July temperature reconstruction that explained 51.2% of the variance in the instrumental record. The reconstruction showed seven cold periods and five warm periods. Cold periods were identified from AD 1472 to 1524, 1599 to 1653, 1661 to 1715, 1732 to 1828, 1837 to 1847, 1865 to 1876 and 1907 to 1926. Warm intervals occurred from AD 1446 to 1471, 1525 to 1598, 1716 to 1731, 1848 to 1864, 1877 to 1906 and 1927 to present. The reconstruction agrees well with nearby tree-ring-based temperature reconstructions. Spatial correlation analyses suggest that our reconstructions provide information on June–July temperature variability for the southeastern Tibetan Plateau and its vicinity. Spectral analyses revealed significant peaks at 2–6, 10.7, 51.2, 102.2 and 204.8 yr. The temperature variability in this area may be affected by ENSO, the Pacific Decadal Oscillation and solar activity.

Related: Review paper finds the so-called unprecedented warmth of the late 20th century is simply a myth

4 comments:

  1. http://nipccreport.org/articles/2013/aug/28aug2013a3.html

    ReplyDelete
  2. another non-hockey-stick published today

    http://www.sciencedirect.com/science/article/pii/S003101821300299X?np=y

    ReplyDelete
    Replies
    1. http://ars.els-cdn.com/content/image/1-s2.0-S003101821300299X-gr8.jpg

      http://ars.els-cdn.com/content/image/1-s2.0-S003101821300299X-gr7.jpg

      Delete
  3. and another

    http://www.sciencedirect.com/science/article/pii/S0031018213003015?np=y

    ReplyDelete