1 / 6

Agassiz

Agassiz. Please notice that this ice core is different with the previous two I analyzed: Crete and Dye3 This ice core has some information not explained by white noise. Unlike the previous two ice cores, which has no information significant than white noise.

barney
Download Presentation

Agassiz

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Agassiz

  2. Please notice that this ice core is different with the previous two I analyzed: Crete and Dye3 This ice core has some information not explained by white noise. Unlike the previous two ice cores, which has no information significant than white noise. IMFs 3-6 have mean period: 14.86, 30.21, 60.82, and 182.68

  3. The blue curve, i.e. sum of IMFs 3-6, seems have ~20 years cycle during 1800-present. Please see the next slide, the Fourier spectrum of IMFs 3-6.

  4. It looks like there are one peak around 20-years. And also, there are some energy distribution around 50-year, too, if we use band-pass filter. I am sorry that I do not know how to test the statistics significance against the red background noise. My own method is based on EMD, which is quite complex.

  5. Composite ice core (same as Chylek et al. 2011) I believe if we use some filters to remove the impacts of 20-year cycle, we could get this ~70-year cycle. As far as I can see, this can only exist in the composite time series, since this cycle is quite nonlinear (its spectrum is wide in any single core), the composite may give better represent.

More Related