Sep 19, 2018
Recent intensification of Amazon flooding extremes driven by strengthened Walker circulation
by
,
Science Advances
- States that although the variability of the Amazon hydrological cycle has been increasing since the late 1990s, its underlying causes have remained elusive
- Uses water levels in the Amazon River to quantify changes in extreme events and then analyze their cause
- Finds that:
- Despite continuing research emphasis on droughts, the largest change over recent decades is a marked increase in very severe floods
- Increased flooding is linked to a strengthening of the Walker circulation, resulting from strong tropical Atlantic warming and tropical Pacific cooling
- Atlantic warming due to combined anthropogenic and natural factors has contributed to enhance the change in atmospheric circulation
- Concludes that whether this anomalous increase in flooding will last depends on the evolution of the tropical inter-ocean temperature difference