A comparison of decadal-to-interdecadal variability and trend in reanalysis datasets using atmospheric angular momentum

Houk Paek, Huei-Ping Huang

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

An intercomparison of the global relative angular momentum M R in five reanalysis datasets, including the Twentieth Century Reanalysis (20CR), is performed for the second half of the twentieth century. The intercomparison forms a stringent test for 20CR because the variability of M R is known to be strongly influenced by the variability of upper-tropospheric zonal wind whereas 20CR assimilated only surface observations. The analysis reveals good agreement for decadal-to-multidecadal variability among all of the datasets, including 20CR, for the second half of the twentieth century. The discrepancies among different datasets are mainly in the slowest component, the long-term trend, of MR. Once the data are detrended, the resulting decadal-to-multidecadal variability shows even better agreement among all of the datasets. This result indicates that 20CR can be reliably used for the analysis of decadal-to-interdecadal variability in the pre-1950 era, provided that the data are properly detrended. As a quick application, it is found that the increase in M R during the 1976/77 climate-shift event remains the sharpest over the entire period from 1871 to 2008 covered by 20CR. The nontrivial difference in the long-term trend between 20CR and the other reanalysis datasets found in this study provides a caution against using 20CR to determine the trend on the centennial time scale that is relevant to climate change. These conclusions are restricted to the quantities that depend strongly on the upper-tropospheric zonal wind, but the approach adopted in this work will be useful for future intercomparisons of the low-frequency behavior of other climate indices in the reanalysis datasets.

Original languageEnglish (US)
Pages (from-to)4750-4758
Number of pages9
JournalJournal of Climate
Volume25
Issue number13
DOIs
StatePublished - Jul 2012

Fingerprint

angular momentum
twentieth century
zonal wind
climate
comparison
trend
timescale
climate change
long-term trend
analysis

Keywords

  • Atmospheric circulation
  • Climate records
  • Climate variability
  • Decadal variability
  • Interdecadal variability
  • Trends

ASJC Scopus subject areas

  • Atmospheric Science

Cite this

A comparison of decadal-to-interdecadal variability and trend in reanalysis datasets using atmospheric angular momentum. / Paek, Houk; Huang, Huei-Ping.

In: Journal of Climate, Vol. 25, No. 13, 07.2012, p. 4750-4758.

Research output: Contribution to journalArticle

@article{b40cadddb4634747b8ace4df3591f903,
title = "A comparison of decadal-to-interdecadal variability and trend in reanalysis datasets using atmospheric angular momentum",
abstract = "An intercomparison of the global relative angular momentum M R in five reanalysis datasets, including the Twentieth Century Reanalysis (20CR), is performed for the second half of the twentieth century. The intercomparison forms a stringent test for 20CR because the variability of M R is known to be strongly influenced by the variability of upper-tropospheric zonal wind whereas 20CR assimilated only surface observations. The analysis reveals good agreement for decadal-to-multidecadal variability among all of the datasets, including 20CR, for the second half of the twentieth century. The discrepancies among different datasets are mainly in the slowest component, the long-term trend, of MR. Once the data are detrended, the resulting decadal-to-multidecadal variability shows even better agreement among all of the datasets. This result indicates that 20CR can be reliably used for the analysis of decadal-to-interdecadal variability in the pre-1950 era, provided that the data are properly detrended. As a quick application, it is found that the increase in M R during the 1976/77 climate-shift event remains the sharpest over the entire period from 1871 to 2008 covered by 20CR. The nontrivial difference in the long-term trend between 20CR and the other reanalysis datasets found in this study provides a caution against using 20CR to determine the trend on the centennial time scale that is relevant to climate change. These conclusions are restricted to the quantities that depend strongly on the upper-tropospheric zonal wind, but the approach adopted in this work will be useful for future intercomparisons of the low-frequency behavior of other climate indices in the reanalysis datasets.",
keywords = "Atmospheric circulation, Climate records, Climate variability, Decadal variability, Interdecadal variability, Trends",
author = "Houk Paek and Huei-Ping Huang",
year = "2012",
month = "7",
doi = "10.1175/JCLI-D-11-00358.1",
language = "English (US)",
volume = "25",
pages = "4750--4758",
journal = "Journal of Climate",
issn = "0894-8755",
publisher = "American Meteorological Society",
number = "13",

}

TY - JOUR

T1 - A comparison of decadal-to-interdecadal variability and trend in reanalysis datasets using atmospheric angular momentum

AU - Paek, Houk

AU - Huang, Huei-Ping

PY - 2012/7

Y1 - 2012/7

N2 - An intercomparison of the global relative angular momentum M R in five reanalysis datasets, including the Twentieth Century Reanalysis (20CR), is performed for the second half of the twentieth century. The intercomparison forms a stringent test for 20CR because the variability of M R is known to be strongly influenced by the variability of upper-tropospheric zonal wind whereas 20CR assimilated only surface observations. The analysis reveals good agreement for decadal-to-multidecadal variability among all of the datasets, including 20CR, for the second half of the twentieth century. The discrepancies among different datasets are mainly in the slowest component, the long-term trend, of MR. Once the data are detrended, the resulting decadal-to-multidecadal variability shows even better agreement among all of the datasets. This result indicates that 20CR can be reliably used for the analysis of decadal-to-interdecadal variability in the pre-1950 era, provided that the data are properly detrended. As a quick application, it is found that the increase in M R during the 1976/77 climate-shift event remains the sharpest over the entire period from 1871 to 2008 covered by 20CR. The nontrivial difference in the long-term trend between 20CR and the other reanalysis datasets found in this study provides a caution against using 20CR to determine the trend on the centennial time scale that is relevant to climate change. These conclusions are restricted to the quantities that depend strongly on the upper-tropospheric zonal wind, but the approach adopted in this work will be useful for future intercomparisons of the low-frequency behavior of other climate indices in the reanalysis datasets.

AB - An intercomparison of the global relative angular momentum M R in five reanalysis datasets, including the Twentieth Century Reanalysis (20CR), is performed for the second half of the twentieth century. The intercomparison forms a stringent test for 20CR because the variability of M R is known to be strongly influenced by the variability of upper-tropospheric zonal wind whereas 20CR assimilated only surface observations. The analysis reveals good agreement for decadal-to-multidecadal variability among all of the datasets, including 20CR, for the second half of the twentieth century. The discrepancies among different datasets are mainly in the slowest component, the long-term trend, of MR. Once the data are detrended, the resulting decadal-to-multidecadal variability shows even better agreement among all of the datasets. This result indicates that 20CR can be reliably used for the analysis of decadal-to-interdecadal variability in the pre-1950 era, provided that the data are properly detrended. As a quick application, it is found that the increase in M R during the 1976/77 climate-shift event remains the sharpest over the entire period from 1871 to 2008 covered by 20CR. The nontrivial difference in the long-term trend between 20CR and the other reanalysis datasets found in this study provides a caution against using 20CR to determine the trend on the centennial time scale that is relevant to climate change. These conclusions are restricted to the quantities that depend strongly on the upper-tropospheric zonal wind, but the approach adopted in this work will be useful for future intercomparisons of the low-frequency behavior of other climate indices in the reanalysis datasets.

KW - Atmospheric circulation

KW - Climate records

KW - Climate variability

KW - Decadal variability

KW - Interdecadal variability

KW - Trends

UR - http://www.scopus.com/inward/record.url?scp=84865172602&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84865172602&partnerID=8YFLogxK

U2 - 10.1175/JCLI-D-11-00358.1

DO - 10.1175/JCLI-D-11-00358.1

M3 - Article

AN - SCOPUS:84865172602

VL - 25

SP - 4750

EP - 4758

JO - Journal of Climate

JF - Journal of Climate

SN - 0894-8755

IS - 13

ER -