Search: onr:"swepub:oai:DiVA.org:su-150933" >
Dynamical propertie...
Dynamical properties and extremes of Northern Hemisphere climate fields over the past 60 years
- Article/chapterEnglish2017
Publisher, publication year, extent ...
-
2017-12-04
-
Copernicus GmbH,2017
-
printrdacarrier
Numbers
-
LIBRIS-ID:oai:DiVA.org:su-150933
-
https://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-150933URI
-
https://doi.org/10.5194/npg-24-713-2017DOI
Supplementary language notes
-
Language:English
-
Summary in:English
Part of subdatabase
Classification
-
Subject category:ref swepub-contenttype
-
Subject category:art swepub-publicationtype
Notes
-
Atmospheric dynamics are described by a set of partial differential equations yielding an infinite-dimensional phase space. However, the actual trajectories followed by the system appear to be constrained to a finite-dimensional phase space, i.e. a strange attractor. The dynamical properties of this attractor are difficult to determine due to the complex nature of atmospheric motions. A first step to simplify the problem is to focus on observables which affect - or are linked to phenomena which affect - human welfare and activities, such as sea-level pressure, 2m temperature, and precipitation frequency. We make use of recent advances in dynamical systems theory to estimate two instantaneous dynamical properties of the above fields for the Northern Hemisphere: local dimension and persistence. We then use these metrics to characterize the seasonality of the different fields and their interplay. We further analyse the large-scale anomaly patterns corresponding to phase-space extremes - namely time steps at which the fields display extremes in their instantaneous dynamical properties. The analysis is based on the NCEP/NCAR reanalysis data, over the period 1948-2013. The results show that (i) despite the high dimensionality of atmospheric dynamics, the Northern Hemisphere sea-level pressure and temperature fields can on average be described by roughly 20 degrees of freedom; (ii) the precipitation field has a higher dimensionality; and (iii) the seasonal forcing modulates the variability of the dynamical indicators and affects the occurrence of phase-space extremes. We further identify a number of robust correlations between the dynamical properties of the different variables.
Subject headings and genre
Added entries (persons, corporate bodies, meetings, titles ...)
-
Messori, GabrieleStockholms universitet,Meteorologiska institutionen (MISU)(Swepub:su)gmess
(author)
-
Alvarez-Castro, M. Carmen
(author)
-
Yiou, Pascal
(author)
-
Stockholms universitetMeteorologiska institutionen (MISU)
(creator_code:org_t)
Related titles
-
In:Nonlinear processes in geophysics: Copernicus GmbH24:4, s. 713-7251023-58091607-7946
Internet link
Find in a library
To the university's database