A century of reduced ENSO variability during the Medieval Climate Anomaly
Creators
- 1. Institute for Geophysics, Jackson School of Geosciences, The University of Texas at Austin, Austin, TX, USA
- 2. Department of Geosciences, The University of Arizona, Tucson, AZ, USA
- 3. Laboratory of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
- 4. High‐precision Mass Spectrometry and Environment Change Laboratory (HISPEC), National Taiwan University, Taipei, Taiwan ROC
Description
Climate model simulations of El Niño–Southern Oscillation (ENSO) behavior for the last
millennium demonstrate interdecadal to centennial changes in ENSO variability that can arise purely
from stochastic processes internal to the climate system. That said, the instrumental record of ENSO does
not have the temporal coverage needed to capture the full range of natural ENSO variability observed in
long, unforced climate model simulations. Here we demonstrate a probabilistic framework to quantify
changes in ENSO variability via histograms and probability density functions using monthly instrumental
and coral‐based sea surface temperature (SST) anomalies from 1900–2005 and 1051–1150 CE. We find that
reconstructed SST anomalies from modern corals from the southwest Pacific capture changes in ENSO
variability that are consistent with instrumental SST data from the central equatorial Pacific. Fossil coral
records indicate 100 years of relatively lower ENSO variability during part of the Medieval Climate Anomaly.
Our results demonstrate that periods of reduced ENSO variability can last a century, far longer in
duration than modern observations in the instrumental record of ENSO, but consistent with results from
unforced climate model simulations
Files
2019PA003742.pdf
Files
(1.6 MB)
| Name | Size | Download all |
|---|---|---|
|
md5:f6d7b4b3e5d44495fdc9e6c37e9dccda
|
1.6 MB | Preview Download |