Low-frequency variabilities for widely different basic flows
Wilbur Y. Chen,Huug van den Dool +1 more
11
TL;DR: In this article, the internal dynamics associated low-frequency variabilities (LFVs) with timescales between 7 days and 31 days, relevant to the potential predictability of monthly means, are investigated.
read more
Abstract: The internal dynamics associated low-frequency variabilities (LFVs) with timescales between 7 days and 31 days, relevant to the potential predictability of monthly means, are investigated. Using observed data and a set of general circulation model produced data, it is shown that the LFV characteristics are distinct for widely different basic flows: much smaller variability for north Pacific cyclonic basic flows than anti-cyclonic basic flows. Their preferred development locations are also distinct. The dynamical processes leading to this large difference is examined in the light of the local barotropic energy conversion between basic flow and low-frequency components. Over the eastern North Pacific where the LFVs are primarily located, the energy conversion decays more from the low-frequency disturbances into the cyclonic basic flows, while much more extraction of LFV energy from the anti-cyclonic basic flows takes place. The internal LFVs considered here are closely related to the climate noise pertaining to the prediction of monthly means. A dynamical link between the phase of El Nino/Southern Oscillation (ENSO) and the potential predictability of monthly means can therefore be established: during the warm phase of ENSO when the mean north Pacific flow is usually cyclonic, the potential predictability of the monthly means can be expected to be higher than during the cool phase, due to the substantially different magnitudes of unpredictable noise being generated through barotropic instability of these different zonally varying basic flows. DOI: 10.1034/j.1600-0870.1995.00102.x
read more
Chat with Paper
AI Agents for this Paper
Find similar papers on Google Scholar, PubMed and Arxiv
Write a critical review of this paper
Analyze citations of this paper to find unaddressed research gaps
Citations
A Large Ensemble Analysis of the Influence of Tropical SSTs on Seasonal Atmospheric Variability
Peitao Peng,Arun Kumar +1 more
TL;DR: Based on a 40-member ensemble for the January-March (JFM) seasonal mean for the 1980-2000 period using an atmospheric general circulation model (AGCM), interannual variability in the first and second moments of probability density function (PDF) of atmospheric seasonal means with sea surface temperatures (SSTs) is analyzed as discussed by the authors.
62
ENSO forcing of the Northern Hemisphere climate in a large ensemble of model simulations based on a very long SST record
TL;DR: In this article, a 35-member ensemble made with SPEEDY, an atmospheric general circulation model (AGCM) of intermediate complexity, was analyzed for the period 1855-2002.
36
Phase‐locked and asymmetric correlations of the wintertime atmospheric patterns with the ENSO
TL;DR: In this article, the correlation between sea surface temperature (SST) anomalies over the Pacific and the dominant patterns of wintertime Northern Hemisphere 500-hPa height is examined by applying statistical techniques such as rotated principal component analysis and composite analysis.
35
Significant change of extratropical natural variability and potential predictability associated with the El Niño/Southern Oscillation
Wilbur Y. Chen,Huug van den Dool +1 more
TL;DR: In this paper, the impact of low-frequency variability, such as the persistent blocking flows, and highfrequency variability represented primarily by the storm tracks, on the potential predictability of the extratropical latitudes between two phases of the ENSO cycle is examined.
31
On the modification of the high‐ and low‐frequency eddies associated with the PNA anomaly: an observational study
Hai Lin,Jacques Derome +1 more
TL;DR: In this article, a 24-year NMC data set was used to study the interannual fluctuations in the extratropical atmospheric flow and the interactions between transients of different frequencies.
29
References
Description of the NMC Global Data Assimilation and Forecast System
TL;DR: The National Meteorological Center's (NMC) Global Data Assimilation and Forecast System is described in some detail.
678
A Climatological Spectral Study of the 500 mb Geopotential Height of the Northern Hemisphere.
TL;DR: In this paper, a 10-year record of the 500 mb geopotential height for the Northern Hemisphere has been expanded into spherical harmonics and filtered in the time domain.
658
The Standard Error of Time-Average Estimates of Climatic Means
TL;DR: In this article, a simple stochastic model is used to estimate the standard error of such an estimation method as a function of averaging time, and the results for long-range forecasting are also discussed.
397
Global Numerical Weather Prediction at the National Meteorological Center
TL;DR: In this article, the authors describe the global numerical weather prediction system of the National Meteorological Center and review recent improvements, the evolution in skill, and current research projects and plans.
334
Medium and extended range predictability and stability of the Pacific/North American mode
TL;DR: In this article, it was shown from an assessment of a small set of extended range forecasts from two centres, and from a much larger set of medium range forecast from one centre, that variability in predictive skill is strongly related to fluctuations in the Pacific/North American (PNA) mode of low frequency variability.
110