Pacific decadal oscillation Pacific Decadal Oscillation 8 Climatology 6 Pacific Ocean 6 Pacific Ocean (Tropical) 6 Tropics 6 Advection 4 Andes 4 Argentina 4 Atmospheric temperature 4 Autumn precipitation 4 Carbon dioxide 4 Circulation anomalies 4 Cyclonic vorticity 4 Drought 4 El Nino 4 El Niño 4 Event classification 4 Global warming 4 Greenhouse gases 4 Heavy precipitation 4 Low frequency 4 Moisture 4 Nickel compounds 4 Nitrogen oxides 4 Ocean engineering 4 Oceanography 4 Permafrost 4 Precipitation 4 Precipitation anomalies 4