Temporal Variation of Relationships between Circulation Modes and Surface Temperature in the Twentieth Century in Winter

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F44555601%3A13520%2F24%3A43898766" target="_blank" >RIV/44555601:13520/24:43898766 - isvavai.cz</a>

Výsledek na webu

<a href="https://journals.ametsoc.org/view/journals/clim/aop/JCLI-D-24-0120.1/JCLI-D-24-0120.1.pdf" target="_blank" >https://journals.ametsoc.org/view/journals/clim/aop/JCLI-D-24-0120.1/JCLI-D-24-0120.1.pdf</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1175/JCLI-D-24-0120.1" target="_blank" >10.1175/JCLI-D-24-0120.1</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Temporal Variation of Relationships between Circulation Modes and Surface Temperature in the Twentieth Century in Winter

Popis výsledku v původním jazyce

Modes of low-frequency variability of atmospheric circulation undergo decadal variations, which affect their spatiotemporal impact on climatic variables on long time scales. Previous studies focused either to one circulation mode or to limited geographical areas. Here, the topic is substantially extended as we provide an overview of long-term variations of all detected circulation modes in the northern extratropics in winter and their impact on relationships with temperature during the twentieth century. Circulation modes are identified by rotated principal component analysis of 500-hPa geopotential heights in the ERA-20C reanalysis; gridded surface temperature data are gained from the Climatic Research Unit Time Series (CRUTS) dataset. Temporal variations of relationships are evaluated by 15-yr running correlations between the circulation modes and surface temperature at all land grid points. Time series of running correlations with all nine circulation modes at all grid points are clustered using the partitioning around medoids (PAM) method into 18 clusters. Both composite maps and temperature advection at the 850-hPa level during specific periods of strengthened, weakened, and normal relationships with surface temperature are used for the determination of mechanisms responsible for the variation of relationships. The main mechanisms are changes in the location, shape, and intensity of centers, and formation or split of centers. These mechanisms affect mainly the intensity and direction of advection, which translate into the magnitude of relationships. Possible causes of changes in the spatial structure of circulation modes are linked with El Ni?o?Southern Oscillation (ENSO), shifts of the Pacific decadal oscillation (PDO), and long-term changes in the sea ice extent.

Název v anglickém jazyce

Temporal Variation of Relationships between Circulation Modes and Surface Temperature in the Twentieth Century in Winter

Popis výsledku anglicky

Modes of low-frequency variability of atmospheric circulation undergo decadal variations, which affect their spatiotemporal impact on climatic variables on long time scales. Previous studies focused either to one circulation mode or to limited geographical areas. Here, the topic is substantially extended as we provide an overview of long-term variations of all detected circulation modes in the northern extratropics in winter and their impact on relationships with temperature during the twentieth century. Circulation modes are identified by rotated principal component analysis of 500-hPa geopotential heights in the ERA-20C reanalysis; gridded surface temperature data are gained from the Climatic Research Unit Time Series (CRUTS) dataset. Temporal variations of relationships are evaluated by 15-yr running correlations between the circulation modes and surface temperature at all land grid points. Time series of running correlations with all nine circulation modes at all grid points are clustered using the partitioning around medoids (PAM) method into 18 clusters. Both composite maps and temperature advection at the 850-hPa level during specific periods of strengthened, weakened, and normal relationships with surface temperature are used for the determination of mechanisms responsible for the variation of relationships. The main mechanisms are changes in the location, shape, and intensity of centers, and formation or split of centers. These mechanisms affect mainly the intensity and direction of advection, which translate into the magnitude of relationships. Possible causes of changes in the spatial structure of circulation modes are linked with El Ni?o?Southern Oscillation (ENSO), shifts of the Pacific decadal oscillation (PDO), and long-term changes in the sea ice extent.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10510 - Climatic research

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Climate

ISSN

0894-8755

e-ISSN

1520-0442

Svazek periodika

2025

Číslo periodika v rámci svazku

38

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

17

Strana od-do

309-326

Kód UT WoS článku

001421404700001

EID výsledku v databázi Scopus

2-s2.0-85217652551