Climate Change: East Coast Atmospheric Rivers and AMOC (Atlantic Meridional Overturning Circulation)

How does the Atlantic Meridional Overturning Circulation (AMOC) affect atmospheric rivers on the East Coast of the USA?

The Atlantic Meridional Overturning Circulation (AMOC) is a system of ocean currents that plays a crucial role in redistributing heat around the Earth. It involves the northward flow of warm surface waters and the southward flow of cold, deep waters. While the direct impact of the AMOC on atmospheric rivers along the East Coast of the USA is complex and can be influenced by various factors, there are some general connections:

1. Temperature Regulation:
   • The AMOC helps regulate sea surface temperatures. Changes in the strength or structure of the AMOC can influence the temperature of the surface waters along the East Coast. Warmer sea surface temperatures can enhance evaporation, potentially contributing to the development of atmospheric rivers.
2. Moisture Source:
   • Atmospheric rivers are long, narrow bands of concentrated moisture in the atmosphere that can transport large amounts of water vapor. Warmer sea surface temperatures associated with a strong AMOC can increase evaporation rates, providing a potential source of moisture for atmospheric rivers.
3. Jet Stream and Weather Patterns:
   • The AMOC is interconnected with atmospheric circulation patterns, including the position of the jet stream. Changes in the AMOC can influence the jet stream's behavior, which, in turn, affects the development and trajectory of atmospheric rivers. The jet stream is a key player in steering weather systems and atmospheric rivers.
4. Sea Level Changes:
   • The AMOC can influence sea level along the East Coast. Changes in sea level can impact the coastal environment and contribute to storm surge events associated with atmospheric rivers.

Climate change is expected to have complex and potentially significant impacts on the jet stream, Atlantic Meridional Overturning Circulation (AMOC), and atmospheric rivers. While the precise details are still an area of ongoing research, here are some general insights into the potential impacts:

Atlantic Meridional Overturning Circulation (AMOC):

1. Weakening or Slowdown:
   • There is concern that climate change could lead to a weakening or slowdown of the AMOC. This is primarily driven by the melting of Greenland's ice sheet and increased freshwater input into the North Atlantic. As freshwater input disrupts the usual sinking of cold, dense water in the North Atlantic, it could weaken the AMOC.
2. Temperature Changes:
   • A weakened AMOC could have implications for sea surface temperatures along the East Coast. Changes in the distribution of heat could influence regional climate patterns and may impact the intensity and frequency of extreme weather events.
3. Sea Level Rise:
   • Changes in the AMOC may contribute to sea level rise along the East Coast. A weakened AMOC could influence the distribution of ocean currents, affecting regional sea level patterns.

Atmospheric Rivers:

1. Increased Intensity and Frequency:
   • Warmer sea surface temperatures associated with climate change can enhance evaporation, providing more moisture to the atmosphere. This increased moisture availability may contribute to the development of more intense and frequent atmospheric rivers.
2. Changing Trajectories:
   • Climate change can influence atmospheric circulation patterns, including the position of the jet stream. Changes in the jet stream may alter the trajectories of atmospheric rivers, influencing where and how they make landfall along the East Coast.
3. Extreme Weather Events:
   • The interaction between a changing AMOC, altered sea surface temperatures, and atmospheric circulation patterns could lead to more intense and potentially damaging extreme weather events, such as heavy rainfall, flooding, and storms.

ALSO SEE:
AMOC: and the Domino Effect Brouse and Mukherjee (2023)