The 20-yr cycle in Greenland ice core records

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

8

Scientific paper

CLIMATIC oscillations with a period of ~20 yr have been reported in North American winter temperature records1,2 midwestern US drought indicators (ref. 3 and J. M. Mitchell, Jr personal communication), dendrochronological data4, and sea-surface temperature anomalies5. These oscillations have mostly been attributed to double sunspot cycles, which seem to occur at about 22-yr intervals. Other possible causes include an 18.6-yr modulation of the diurnal and semidiurnal lunar tidal forces5. Critics6,7 of these observations argue that such oscillations may only be an artefact of a red noise record, and are not uniformly present in a wide range of climatic data. It has also been argued that even if the oscillations are significant, their small amplitude renders them relatively unsuitable for climatic prediction1. However, if such oscillations prove to be real, identifying their nature and possible causes, even though their amplitude is small, can enhance our understanding of climatic change. To gain more insight into such 20-yr oscillations, we have examined characteristic oscillations in Greenland ice core oxygen isotope records. The results show that the strongest spectral peak occurs at a period of 20+/-0.5 yr with a statistically significant amplitude. This period is essentially the same as that found in eastern North American winter temperatures1. Moreover this 20-yr oscillation is found to be coherent in phase with the dominant variation in the Sun's motion about the centre of mass of the Solar System. This motion has been hypothesised8 to be closely linked with sunspots. On the basis of these observations we speculate here that a 20-yr oscillation may be a more fundamental solar and/or climatic oscillation than the nominal 22-yr cycle often mentioned.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The 20-yr cycle in Greenland ice core records does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The 20-yr cycle in Greenland ice core records, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The 20-yr cycle in Greenland ice core records will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1486650

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.