Thursday, August 15, 2013

New paper finds Ontario climate change controlled by solar activity

A paper published today in The Holocene reconstructs temperatures in Ontario, Canada over the past ~9,200 years and finds temperatures correlated to reconstructed solar activity on decadal and millennial time scales. According to the authors, "The results also indicate the presence of millennial-scale cycles possibly comparable with the globally recognized Bond cycles that have been correlated to fluctuations in solar irradiance." The IPCC claims small variations in solar activity cannot account for climate change, but this paper and many other peer-reviewed publications show that solar activity can be amplified by a variety of mechanisms to cause climate change.

A Holocene paleoclimate reconstruction for eastern Canada based on δ18O cellulose of Sphagnum mosses from Mer Bleue Bog

  1. Hafida El Bilali
  2. R Timothy Patterson
  3. Andreas Prokoph
  1. Ottawa-Carleton Geoscience Centre and Department of Earth Sciences, Carleton University, Canada
  1. Andreas Prokoph, Ottawa-Carleton Geoscience Centre and Department of Earth Sciences, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada. Email: aprokocon@aol.com

Abstract

We present a ~9200 yr high-resolution oxygen isotope record of plant cellulose (δ18Ocel) from the peat deposits of Mer Bleue Bog, Ontario and apply it as a proxy for paleotemperature reconstruction in Eastern Canada. The results show that δ18Ocel of Sphagnum follows the general pattern of the Northern Hemisphere reconstructed paleotemperature record for the last 2000 years at a ratio of ~2‰δ18Ocel/°C. The δ18Ocel record [a temperature proxy] of ombrotrophic phase of Mer Bleue Bog is also in accordance with major features of the Holocene sunspot number reconstruction. Three distinct time intervals have low δ18Ocel values: 200–800 cal. BP (‘Little Ice Age’); 2800–3400 cal. BP synchronous to a cooling period reported elsewhere in North America; and 4200–4600 cal. BP corresponding to a cooling interval in the North Atlantic region. These cooling periods also correlate well with negative excursions in the Holocene sunspot and cosmogenic 10Be [a proxy for solar activity] records. A fourth period of low δ18Ocel values between AD1810 and 1820 may be related to the extremely cold summer of 1816 and cooler subsequent years, which occurred in the aftermath of the Tambora volcanic eruption, or possibly cooling associated with the early 19th century Dalton solar minimum. The results also indicate the presence of millennial-scale cycles possibly comparable with the globally recognized Bond cycles that have been correlated to fluctuations in solar irradiance.

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