Ocean windfarms and natural fisheries don't mix

What we've learned about the Gulf of Maine's natural patterns, and their vulnerability to disruption, combining the 2021 NOAA study  "Variability of Deep Water in Jordan Basin of the Gulf of Maine: Influence of Gulf Stream Warm Core Rings and the Nova Scotia Current."

Jiabi Du, Weifeng G. Zhang, Yizhen Li

Published on: 12/02/2021

Primary Contact(s): yizhen.li@noaa.govinsights with our earlier analyses:

Vulnerable Natural Patterns:

1. Deep Water Exchange System

• The newly discovered 3-month transit time for slope water is critical
• This timing evolved to match seasonal biological cycles
• Wind farm-induced mixing could:
  • Speed up or slow down this transit time
  • Create "short circuits" in the natural flow
  • Disrupt the temperature inversion pattern (warmer winter/colder summer deep water)

2. Energy Transfer Disruption

• Our earlier calculations showed ~6 gigawatts of wind energy could be diverted
• This energy normally helps drive:
  • Surface mixing
  • Current maintenance
  • Seasonal turnover patterns
• Removing this energy could weaken these processes

3. Stratification Effects

• The NOAA study shows how Nova Scotia Current's fresh water creates important stratification
• Wind farm wakes could:
  • Break down natural stratification barriers
  • Create artificial mixing zones
  • Interfere with the natural preservation of deep water properties

4. Nutrient Cycling Impacts

• The 30% nutrient contribution from slope water is crucial
• Disrupted patterns could affect:
  • Timing of nutrient delivery
  • Distribution patterns
  • Concentration levels in different water layers

5. Biological Timeline Disruption

• Natural systems depend on predictable patterns
• Species affected could include:
  • Plankton bloom timing
  • Fish spawning cycles
  • Larval transport
  • Feeding migrations

6. Cumulative Effects

• Multiple wind farms could create:
  • Overlapping zones of disruption
  • Cascading effects on currents
  • Complex interactions with natural processes
  • Year-round rather than seasonal impacts

7. Ecosystem Timing Mismatches

• Could create "ecological disconnect" where:
  • Food isn't available when needed
  • Spawning doesn't match optimal conditions
  • Migration patterns become less effective

This vulnerability is particularly concerning because:

1. The Gulf of Maine is already experiencing rapid climate change
2. Many commercial species depend on these precise patterns
3. Once disrupted, these patterns may be difficult or impossible to restore
4. Effects could extend far beyond wind farm boundaries

For fisheries and ecosystem managers, this means:

• Greater uncertainty in predicting stock behavior
• Possible changes in traditional fishing grounds
• Need for more intensive monitoring
• Potential for unexpected ecosystem shifts

Would you like me to elaborate on any of these points or explore specific implications for particular species or fishing operations?