TY - JOUR
T1 - Climatological large-scale circulation patterns over the Middle Americas Region
AU - Ochoa-Moya, Carlos A.
AU - Cala-Pérez, Yoel A.
AU - Díaz-Esteban, Yanet
AU - Castro, Christopher L.
AU - Ordoñez-Peréz, Paulina
AU - Quintanar, Arturo I.
N1 - Publisher Copyright:
© 2020 by the authors.
PY - 2020/7/1
Y1 - 2020/7/1
N2 - In this study, twenty large-scale circulation patterns are identified to generate a synoptic classification ofWeather Types (WT) over a region that comprises Mexico, the Intra-Americas Seas, Central America, and northern South America. This classification is performed using Self-Organizing Maps (SOMs) with mean sea-level pressure standardized anomalies from reanalysis. The influence of quasi-permanent pressure centers over the region, such as North Atlantic Subtropical High (NASH) and North Pacific High (NPH) are well captured. Seasonal variability of high-pressure centers for dry (November-April) and wet (May-October) periods over the entire region are also well represented in amplitude and pattern among the WTs. The NASH influence and intensification of the Caribbean low-level jet and the North American monsoon system is well captured. During the dry period, a strong trough wind advects cold air masses from mid-latitudes to the subtropics over the western Atlantic Ocean. High-frequency transitions among WTs tend to cluster around the nearest neighbors in SOM space, while low-frequency transitions occur along columns instead of rows in the SOM matrix. Low-frequency transitions are related to intraseasonal and seasonal scales. The constructed catalog can identify near-surface atmospheric circulation patterns from a unified perspective of synoptic climate variability, and it is in high agreement with previous studies for the region.
AB - In this study, twenty large-scale circulation patterns are identified to generate a synoptic classification ofWeather Types (WT) over a region that comprises Mexico, the Intra-Americas Seas, Central America, and northern South America. This classification is performed using Self-Organizing Maps (SOMs) with mean sea-level pressure standardized anomalies from reanalysis. The influence of quasi-permanent pressure centers over the region, such as North Atlantic Subtropical High (NASH) and North Pacific High (NPH) are well captured. Seasonal variability of high-pressure centers for dry (November-April) and wet (May-October) periods over the entire region are also well represented in amplitude and pattern among the WTs. The NASH influence and intensification of the Caribbean low-level jet and the North American monsoon system is well captured. During the dry period, a strong trough wind advects cold air masses from mid-latitudes to the subtropics over the western Atlantic Ocean. High-frequency transitions among WTs tend to cluster around the nearest neighbors in SOM space, while low-frequency transitions occur along columns instead of rows in the SOM matrix. Low-frequency transitions are related to intraseasonal and seasonal scales. The constructed catalog can identify near-surface atmospheric circulation patterns from a unified perspective of synoptic climate variability, and it is in high agreement with previous studies for the region.
KW - Self-organizing maps
KW - Synoptic climatology
KW - Weather types
UR - http://www.scopus.com/inward/record.url?scp=85088146685&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85088146685&partnerID=8YFLogxK
U2 - 10.3390/atmos11070745
DO - 10.3390/atmos11070745
M3 - Article
AN - SCOPUS:85088146685
SN - 2073-4433
VL - 11
JO - Atmosphere
JF - Atmosphere
IS - 7
M1 - 745
ER -