Format

Send to

Choose Destination
Sci Rep. 2014 Oct 17;4:6651. doi: 10.1038/srep06651.

Combined effects of the Pacific Decadal Oscillation and El Niño-Southern Oscillation on global land dry-wet changes.

Author information

1
1] Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, China [2] State Key Laboratory of Tropical Oceanography, Chinese Academy of Sciences, South China Sea Institute of Oceanology, Guangzhou, China.
2
Key Laboratory for Semi-Arid Climate Change of the Ministry of Education, College of Atmospheric Sciences, Lanzhou University, China.
3
State Key Laboratory of Tropical Oceanography, Chinese Academy of Sciences, South China Sea Institute of Oceanology, Guangzhou, China.

Abstract

The effects of natural variability, especially El Niño-Southern Oscillation (ENSO) effects, have been the focus of several recent studies on the change of drought patterns with climate change. The interannual relationship between ENSO and the global climate is not stationary and can be modulated by the Pacific Decadal Oscillation (PDO). However, the global land distribution of the dry-wet changes associated with the combination of ENSO and the PDO remains unclear. In the present study, this is investigated using a revised Palmer Drought Severity Index dataset (sc_PDSI_pm). We find that the effect of ENSO on dry-wet changes varies with the PDO phase. When in phase with the PDO, ENSO-induced dry-wet changes are magnified with respect to the canonical pattern. When out of phase, these dry-wet variations weaken or even disappear. This remarkable contrast in ENSO's influence between the two phases of the PDO highlights exciting new avenues for obtaining improved global climate predictions. In recent decades, the PDO has turned negative with more La Niña events, implying more rain and flooding over land. La Niña-induced wet areas become wetter and the dry areas become drier and smaller due to the effects of the cold PDO phase.

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center