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Updated: Jul 13, 2026
08:42
Measurement of the Directional Information Flow in fNIRS-Hyperscanning Data using the Partial Wavelet Transform Coherence Method
Published on: September 3, 2021
The North Atlantic Oscillation: past, present, and future.
M H Visbeck1, J W Hurrell, L Polvani
1Department of Earth and Environmental Sciences, Columbia University, New York, NY 10027, USA. visbeck@Loleo.columbia.edu
Summary
The Atlantic climate shows significant variability, largely driven by the North Atlantic Oscillation (NAO). Recent shifts in the NAO suggest human activities may be influencing climate change in this region.
Area of Science:
- Climatology
- Atmospheric Science
- Oceanography
Background:
- The Atlantic climate system displays significant variability across multiple timescales.
- The North Atlantic Oscillation (NAO), a major climate driver, influences weather patterns from North America to Eurasia.
- Recent decades show a notable shift in the NAO's phase from negative to positive.
Purpose of the Study:
- To investigate the low-frequency variability in the North Atlantic climate.
- To understand the mechanisms driving recent changes in the North Atlantic Oscillation (NAO).
- To assess the potential role of human activities in observed climate shifts.
Main Methods:
- Analysis of historical climate data for the Atlantic sector.
- Statistical examination of atmospheric mass oscillations and their centers of action.
- Time-series analysis to identify trends in the NAO phase over the last three decades.
Main Results:
- The North Atlantic Oscillation (NAO) is a primary driver of climate variability in the Atlantic sector.
- NAO impacts winter climate across a vast geographical area, including North America, Europe, and Asia.
- A significant shift in the NAO phase towards positive values has occurred over the past 30 years.
Conclusions:
- Low-frequency changes in North Atlantic climate are complex and not fully understood.
- Human activities are increasingly implicated as a significant factor in recent North Atlantic climate variability and NAO phase shifts.
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