The influence of the El Niño–Southern Oscillation (ENSO) on tropical cyclone intensity in the western North Pacific basin is examined. Accumulated cyclone energy (ACE), constructed from the best-track dataset for the region for the period 1950–2002, and other related variables are analyzed. ACE is positively correlated with ENSO indices. This and other statistics of the interannually varying tr...

This chapter examines the sensitivity of tropical Pacific interannual variability to changes in the climatological background state. Chapter 5 showed that although a wide variety of climate perturbations can affect the equatorial Pacific, the equatorial structure of the response tends to be similar in each case. Due to strong coupled feedbacks like those active in ENSO, the Pacific climatology ...

The complex nature of the El Niño–Southern Oscillation (ENSO) is often simplified through the use of conceptual models, each of which offers a different perspective on the ocean–atmosphere feedbacks underpinning the ENSO cycle. One theory, the unified oscillator, combines a variety of conceptual frameworks in the form of a coupled system of delay differential equations. The system produces a se...

Numerous studies have demonstrated statistical associations between the El Niño–Southern Oscillation (ENSO) and precipitation in the Mediterranean basin. The dynamical bases for these teleconnections have yet to be fully identified. Here, observational analyses and model simulations are used to show how ENSO variability affects rainfall over southwestern Europe (Iberia, Southern France, and Ita...

[1] The effect of El Niño-Southern Oscillation (ENSO) on the frequency and character of Northern Hemisphere major mid-winter stratospheric sudden warmings (SSWs) is evaluated using a meteorological reanalysis data set and comprehensive chemistry-climate models. There is an apparent inconsistency between the impact of opposite phases of ENSO on the seasonal mean vortex and on SSWs: El Niño leads...

El Niño Southern Oscillation (ENSO) is the most dominant interannual signal of climate variability and has a strong influence on climate over large parts of the world. In turn, it strongly influences many natural hazards (such as hurricanes and droughts) and their resulting socioeconomic impacts, including economic damage and loss of life. However, although ENSO is known to influence hydrology ...

The El Niño/Southern Oscillation (ENSO) phenomenon, originating in the Tropical Pacific, is the strongest natural interannual climate signal and has widespread effects on the global climate system and the ecology of the Tropical Pacific. Any strong change in ENSO statistics will therefore have serious climatic and ecological consequences. Most global climate models do simulate ENSO, although la...

Using climate signals in streamflow forecasting has been subject of numerous studies in recent years. The objective of this research is to examine the effects of El NinoSouthern Oscillation (ENSO) on streamflow forecast in south-western Iran. To achieve this, a statistical non-parametric forecasting model is developed based on K-nearest neighbor (KNN) method. Southern-Oscillation Index (SOI) is...

Observational evidence shows that the Walker circulation (WC) in the tropical Pacific has strengthened in recent decades. In this study, we examine the WC trend for 1979–2005 and its relationship with the precipitation associated with the El Niño Southern Oscillation (ENSO) using the sea surface temperature (SST)-constrained Atmospheric Model Intercomparison Project (AMIP) simulations of the Co...

The El Niño/Southern Oscillation (ENSO) response to anthropogenic climate change is assessed in the following 1◦ nominal resolution CCSM4 CMIP5 simulations: 20th century ensemble, pre-industrial control, 21st century projections and stabilized 2100-2300 ‘extension runs’. ENSO variability weakens slightly with CO2; however, various significance tests reveal that changes are insignificant at all ...