A multi-model analysis of 'Little Ice Age' climate over China.

Using the numerical experiments undertaken by nine climate models within the framework of the Paleoclimate Modeling Intercomparison Project Phase 3 (PMIP3), the ensemble simulations with the Community Earth System Model for the last millennium (CESM-LME), and proxy data, we investigate the climate over China during the 'Little Ice Age' (LIA; from 1450 to 1850 CE) against the background of the last millennium (from 850 to 1850 CE). The surface air temperature averaged over China generally decreased over time during the last millennium, with several multi-decadal to centennial variations superimposed on the long-term cooling. Relative to the climatology of the last millennium, the annual surface temperature during the LIA decreased over the country, with an average cooling of −0.07°C for the median of the PMIP3 models. Different magnitudes of cooling occurred in all seasons except spring. The cooling over China during the LIA was largely attributed to changes in volcanic eruptions and land use, while the change in orbital parameters played a role on a seasonal scale. The precipitation over China during the LIA decreased for the annual mean and summer and autumn but slightly increased in winter and spring. Model–data comparisons indicate that the models reproduced the colder and drier climate of the LIA reasonably, although there are some differences in certain aspects. [ABSTRACT FROM AUTHOR]