Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published April 1, 2016 | Published + Supplemental Material
Journal Article Open

Temporal and Spatial Variability of Precipitation from Observations and Models

Abstract

Principal component analysis (PCA) is utilized to explore the temporal and spatial variability of precipitation from GPCP and a CAM5 simulation from 1979 to 2010. In the tropical region, the interannual variability of tropical precipitation is characterized by two dominant modes (El Niño and El Niño Modoki). The first and second modes of tropical GPCP precipitation capture 31.9% and 15.6% of the total variance, respectively. The first mode has positive precipitation anomalies over the western Pacific and negative precipitation anomalies over the central and eastern Pacific. The second mode has positive precipitation anomalies over the central Pacific and negative precipitation anomalies over the western and eastern Pacific. Similar variations are seen in the first two modes of tropical precipitation from a CAM5 simulation, although the magnitudes are slightly weaker than in the observations. Over the Northern Hemisphere (NH) high latitudes, the first mode, capturing 8.3% of the total variance of NH GPCP precipitation, is related to the northern annular mode (NAM). During the positive phase of NAM, there are negative precipitation anomalies over the Arctic and positive precipitation anomalies over the midlatitudes. Over the Southern Hemisphere (SH) high latitudes, the first mode, capturing 13.2% of the total variance of SH GPCP precipitation, is related to the southern annular mode (SAM). During the positive phase of the SAM, there are negative precipitation anomalies over the Antarctic and positive precipitation anomalies over the midlatitudes. The CAM5 precipitation simulation demonstrates similar results to those of the observations. However, they do not capture both the high precipitation anomalies over the northern Pacific Ocean or the position of the positive precipitation anomalies in the SH.

Additional Information

© 2016 American Meteorological Society. Manuscript received 6 May 2015, in final form 23 January 2016. We thank two anonymous reviewers and the editor for helpful comments. XJ and YLY are supported by the OCO-2 project, NASA Grant NNX13AK34G NASA, and ROSES-2010 NEWS Grant NNX13AC04G. LL is supported by NASA ROSES Cassini Data Analysis Program.

Attached Files

Published - jcli-d-15-0325_2E1.pdf

Supplemental Material - 10_2E1175_jcli-d-15-0325_2Es1.doc

Files

jcli-d-15-0325_2E1.pdf
Files (2.5 MB)
Name Size Download all
md5:6530df20885ecc4f93cf6334cd045631
2.0 MB Preview Download
md5:e6db528bb2f84ad00d7419eee32856b9
458.2 kB Download

Additional details

Created:
August 22, 2023
Modified:
October 18, 2023