1649 / 2019-08-25 08:49:15

The influences of volcanic eruptions on decadal climate changes

1、第四纪地质与全球变化 > 专题4：多时空尺度古气候模拟

The influences and mechanisms of volcanic eruptions on two aspects of decadal climate, decadal megadroughts over the eastern China and decadal climate variability (i.e., PDO and AMO) were investigated using model simulations from from the Community Earth System Model (CESM) Last Millennium Ensemble (LME) archive and Paleoclimate Modeling Intercomparison Project phase 3 (PMIP3) archive. Initial assessments of model simulations showed that Models can reproduce similar frequency, durations, and magnitudes with the reconstructed megadroughts, but not temporal synchronous, indicating that the internal variability trigger the megadroughts. While, the volcanic forcing sensitivity experiments produce fewer megadroughts than the reconstruction and control simulation. Volcanic forcing tends to reduce the megadrought frequencies through a negative PDO-like SSTA pattern, with larger SSTA over the eastern North Pacific than over the central North Pacific. The intensities and persistence of negative PDO and AMO patterns induced by volcanic eruptions increase with the strength of volcanic eruptions. A case study of Ming Dynasty Drought showed that this drought is a typical drought triggered by internal variability and strengthened by the volcanic eruption, and this intensification is stronger during the late stage of droughts.