The climate science community sources a suite of global climate models to help decision makers understand the projections of future climate change and related impacts, among the most widely used are the Coupled Model Intercomparison Project, Phase 5 (CMIP5) models included in the IPCC's Fifth Assessment Report (AR5). Key projected climate trends are summarized below:
- Temperatures in the Pacific are projected to increase between 1.4 and 3.1°C.
- Increased surface air temperature between 1.0—4.17°C in the northern Pacific and 0.99—3.11°C in the southern Pacific by 2070, resulting in increases in sea surface temperature of 1.0—3.0°C.
- The future of rainfall patterns across the Pacific region is a subject of continued debate, with models projecting +/-25% changes in rainfall. As yet it is not possible to get a clear picture for precipitation change, due to large model uncertainties.
- While average annual and monthly rainfall changes are inconsistent across this region of the Pacific, recent evidence and model simulations point to a more frequent occurrence of El Niño weather patterns, bringing an increase in drought conditions along this region. These more frequent El Niño events are believed to be associated with climate change, although some disagreement exists within the science community on this point.
- Rainfall increases or decreases from -2.7% to +25.8% in the northern Pacific, and -14% to +14.6% in the southern Pacific, worsening floods or droughts; despite large uncertainty surrounding rainfall projections, future El Niño-related events are likely to drive many of the changes in rainfall, past experience with El Niño may be used as a proxy for considering future changes in climate.
This section provides the options to visualize climate variables and indices derived from scientifically vetted CMIP5 projections for different timeframes, statistics, emission scenarios, and climate models.