Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 112, Issue 11, Pages 3253-3256Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1420291112
Keywords
climate variability; cosmic rays; global temperature; causality; convergent cross mapping
Categories
Funding
- Department of Energy [DE-SC0005305]
- University of Wisconsin-Milwaukee Research Growth Initiative Grant [101X286]
- National Science Foundation China [41275087]
- Deutsche Bank-Jameson Complexity Studies Fund
- McQuown Chair in Natural Science
- National Science Foundation [DEB1020372]
- National Science Foundation Graduate Research Fellowship Program
- Sugihara Family Trust
- U.S. Department of Energy (DOE) [DE-SC0005305] Funding Source: U.S. Department of Energy (DOE)
- Division Of Environmental Biology
- Direct For Biological Sciences [1020372] Funding Source: National Science Foundation
Ask authors/readers for more resources
As early as 1959, it was hypothesized that an indirect link between solar activity and climate could be mediated by mechanisms controlling the flux of galactic cosmic rays (CR) [Ney ER (1959) Nature 183:451-452]. Although the connection between CR and climate remains controversial, a significant body of laboratory evidence has emerged at the European Organization for Nuclear Research [Duplissy J, et al. (2010) Atmos Chem Phys 10:1635-1647; Kirkby J, et al. (2011) Nature 476(7361):429-433] and elsewhere [Svensmark H, Pedersen JOP, Marsh ND, Enghoff MB, Uggerhoj Ul (2007) Proc R Soc A 463:385-396; Enghoff MB, Pedersen JOP, Uggerhoj Ul, Paling SM, Svensmark H (2011) Geophys Res Lett 38:L09805], demonstrating the theoretical mechanism of this link. In this article, we present an analysis based on convergent cross mapping, which uses observational time series data to directly examine the causal link between CR and year-to-year changes in global temperature. Despite a gross correlation, we find no measurable evidence of a causal effect linking CR to the overall 20th-century warming trend. However, on short interannual timescales, we find a significant, although modest, causal effect between CR and short-term, year-to-year variability in global temperature that is consistent with the presence of nonlinearities internal to the system. Thus, although CR do not contribute measurably to the 20th-century global warming trend, they do appear as a nontraditional forcing in the climate system on short interannual timescales.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available