NOAA/WDS Paleoclimatology - East Asia 1150 Year Composite Reconstruction of Multidecadal Temperature Changes

The drivers of multidecadal- to centennial-scale variability in East Asian temperature, apparent in temperature reconstructions, are poorly understood. Here we apply a multivariate regression analysis to distinguish the influences of large-scale modes of internal variability (Atlantic Multidecadal Oscillation and Pacific Multidecadal Oscillation) and external natural (orbital, solar, and volcanic) and anthropogenic (greenhouse gas concentrations, aerosols, and land use changes) forcings on East Asian warm-season temperature over the period 850-1999 CE (Common Era). We find that ~80% of the temperature change on time scales longer than 30 years can be explained including all drivers over the full-length period. The Pacific Multidecadal Oscillation was the most important driver of multidecadal temperature variability during the Medieval Climate Anomaly (here 950-1250), while solar contribution was important during the Little Ice Age (here 1350-1850). Since 1850, two thirds of temperature change can be explained with anthropogenic forcing, whereas one third was related mainly to the Atlantic Multidecadal Oscillation and volcanic forcing.