Identification

Title

Influence of the North Pacific Victoria mode on the Pacific ITCZ summer precipitation

Abstract

This study demonstrates the close connection between the second dominant mode of spring sea surface temperature anomalies (SSTAs) in the North Pacific poleward of 20°N, referred to as the Victoria mode (VM), and the Pacific Intertropical Convergence Zone (ITCZ) precipitation during the following summer. Our analysis shows that strong positive VM cases are followed by positive precipitation anomalies over the central-eastern Pacific ITCZ region, in association with negative precipitation anomalies over the ITCZ regions of the tropical western Pacific and eastern North Pacific. The hypothesized physical mechanism through which the spring VM induces the Pacific ITCZ summer precipitation is similar to but slightly different from the seasonal footprinting mechanism. During strong positive VM cases, SSTAs in the subtropics associated with the spring VM persist until summer and develop toward the equator, where low-level convergence and divergence caused by SSTA gradients give rise to enhanced precipitation over the central-eastern Pacific ITCZ region and to reduced precipitation over the ITCZ regions of the tropical western Pacific and eastern North Pacific. The thermodynamic ocean-atmosphere coupling between the ITCZ and SSTAs associated with the VM may play a vital role in the initiation of El Niño–Southern Oscillation (ENSO) events. The VM influence on tropical Pacific summer precipitation can be passed on to the next year through its influence on ENSO. A VM-based linear model is established to predict the tropical Pacific summer precipitation, which yields skillful forecasts for summer precipitation across almost the entire tropical Pacific.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d7125ttq

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2015-02-16T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact