Abstract
The oscillatory behaviour of the climate system on decadal timescales
before the instrumental record is hard to quantify. However, knowledge of
this variability is important for putting current changes in context and for
supporting reliable future predictions. Here we investigate the recurrent
component of Holocene climate variability in the North Atlantic sector from
10,500 to 2,000 years ago by conducting a frequency analysis of both an
annually laminated climate record from a lake in England and outputs from a
long transient simulation of the Atlantic meridional overturning circulation.
We find consistent decadal variability over the past 6,700 years and before
8,500 years before present, probably reflecting predominance of solar and
ocean forcings. Between these dates, climate variability was dampened on
decadal timescales. Our results suggest that meltwater discharge into the
North Atlantic and the subsequent hydrographic changes, from the opening
of the Hudson Bay until the final collapse of the Laurentide Ice Sheet,
disrupted the decadal cyclic signals for more than a millennium. Given
the current acceleration of the Greenland Ice Sheet melting in response
to global warming, this study provides long-term evidence of potential
challenges predicting future patterns of the climate system.
before the instrumental record is hard to quantify. However, knowledge of
this variability is important for putting current changes in context and for
supporting reliable future predictions. Here we investigate the recurrent
component of Holocene climate variability in the North Atlantic sector from
10,500 to 2,000 years ago by conducting a frequency analysis of both an
annually laminated climate record from a lake in England and outputs from a
long transient simulation of the Atlantic meridional overturning circulation.
We find consistent decadal variability over the past 6,700 years and before
8,500 years before present, probably reflecting predominance of solar and
ocean forcings. Between these dates, climate variability was dampened on
decadal timescales. Our results suggest that meltwater discharge into the
North Atlantic and the subsequent hydrographic changes, from the opening
of the Hudson Bay until the final collapse of the Laurentide Ice Sheet,
disrupted the decadal cyclic signals for more than a millennium. Given
the current acceleration of the Greenland Ice Sheet melting in response
to global warming, this study provides long-term evidence of potential
challenges predicting future patterns of the climate system.
| Original language | English |
|---|---|
| Pages (from-to) | 357-362 |
| Journal | Nature Geoscience |
| Volume | 16 |
| Publication status | Published - 23 Mar 2023 |
