Introductory Overview

• Main Author: Raymond C. Smith
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; Arctic; Greenland; The Antarctic; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.456.2346; http://pal.lternet.edu/docs/bibliography/Public/350lterc.pdf

T he El Nino--Southem Oscillation (ENSO) is a coupled ocean-atmosphere phenomena that has a worldwide impact on climate. An aperiodic phe-nomena that reoccurs every 2 to 7 year~. the ENSO is second only to seasonal vari-ability in driving worldwide weather patterns. As Greenland notes in chapter 6. the term "quasi-quintennial " is chosen to recognize that climatic events other than El'.'SO-related events might occur at this timescale. although it is widely recognized that ENSO contributes the lion's share of the higher frequency variability in pale-orecords of the past several thousand years. In this section. we consider variabil-ity with cycle ~ of 2 to 7 years and the resulting ecological response. Although we emphasize the ENSO timescale in this section. there is growing evidence that this phenomena is neither spatially nor temporally stable lwer longer time periods. In-deed. Allan (2000) suggests the ENSO climatic variability must be viewed within the context of climate tluctuations at decadal to interdecadal timescales. which often modulate the higher frequency ENSO variability. As a consequence. results in this and the next section often display overlapping patterns of variability. and their separation is not sharply defined. An important theme in this section is the worldwide intluence of EN SO-related climate variability. Greenland (chapter 6) provides an LTER network overvie\\ with an analysis of EN SO-related variability of temperature and precipitation records for many LTER sites from the Arctic to the Antarctic. He discusses the gen-eral nature of ENSO and its climatic effects. summarizes previous climate-related work in the LTER network. and provides a cross-site analysis of the correlations between the Southern Oscillation Index (SOl) and temperature and precipitation at LTER sites. His results are consistent with the expected patterns of the geography of ENSO effects on the climate. Greenland's cross-site analysis provides the basi