Midlatitude cooling caused by geomagnetic field minimum during polarity reversal

The climatic effects of cloud formation induced by galactic cosmic rays (CRs) has recently become a topic of much discussion. The CR–cloud connection suggests that variations in geomagnetic field intensity could change climate through modulation of CR flux. This hypothesis, however, is not well-test...

Full description

Saved in:
Bibliographic Details
Published in:Proceedings of the National Academy of Sciences - PNAS 2013-01, Vol.110 (4), p.1215-1220
Main Authors: Kitaba, Ikuko, Hyodo, Masayuki, Katoh, Shigehiro, Dettman, David L., Sato, Hiroshi
Format: Article
Language:English
Subjects:
climate
Climate change
Climate models
Clouds
Cooling
Cosmic rays
Diatoms
Earth sciences
Earth, ocean, space
Exact sciences and technology
Geomagnetic fields
geophysics
Isotope geochemistry
Isotope geochemistry. Geochronology
isotopes
latitude
Magnetic fields
magnetism
Marine and continental quaternary
oxygen
Paleobotany
Paleoclimate science
Paleoclimatology
Paleontology
Physical Sciences
Pollen
sea level
Sediments
Surficial geology
temperature
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The climatic effects of cloud formation induced by galactic cosmic rays (CRs) has recently become a topic of much discussion. The CR–cloud connection suggests that variations in geomagnetic field intensity could change climate through modulation of CR flux. This hypothesis, however, is not well-tested using robust geological evidence. Here we present paleoclimate and paleoenvironment records of five interglacial periods that include two geomagnetic polarity reversals. Marine oxygen isotope stages 19 and 31 contain both anomalous cooling intervals during the sea-level highstands and the Matuyama–Brunhes and Lower Jaramillo reversals, respectively. This contrasts strongly with the typical interglacial climate that has the temperature maximum at the sea-level peak. The cooling occurred when the field intensity dropped to 40% increase in CR flux. The climate warmed rapidly when field intensity recovered. We suggest that geomagnetic field intensity can influence global climate through the modulation of CR flux.
ISSN:0027-8424
1091-6490
DOI:10.1073/pnas.1213389110