The ACPI Climate Change Simulations

摘要: The Parallel Climate Model (PCM) has been used in the Accelerated ClimatePrediction Initiative (ACPI) Program to simulate global climateresponse projected CO2, sulfate, and other greenhouse gasforcingunder a business-as-usual emissions scenario during 21st century. In these runs, oceans were initialized 1995 conditions by group from Scripps Institution of Oceanography institutions. An ensemble three model runs was then carried out year 2099 using forcing. Atmospheric data fromthese saved at 6-hourly intervals (hourly for certain criticalfields) support ACPI objective accurately modeling hydrologicalcycles over western U.S. It is shown that initialization to1995 partly removes un-forced oceanic temperature salinity drifts occurred standard 20th century integration. show surface increase 3–8 °C northern high-latitudes end century, 1–2 oceans. This generally within ±0.1°Cof without ocean initialization. exception theAntarctic circumpolar where air cooler theACPI run; however scatter large this region. Althoughthe difference climate minimalbetween traditionally spun up it might be largerfor CGCMs with higher sensitivity or larger drifts. Ourresults suggest effect small errors (such asthose associated drifts) on CGCM-simulated changesfor next 50–100 years may negligible.