# Upsweep peaks in spring and autumn, which may reflect either the source or seasonal propagation.

> Upsweep peaks in spring and autumn, which may reflect either the source or seasonal propagation.

Source: https://mysteriesdept.com/mysteries/noaa-ocean-sounds/evidence/EVD0D9C7N3C1XRY/upsweep-peaks-in-spring-and-autumn-which-may-reflect-either  
Publisher: Mysteries Department  
Licence: CC BY 4.0 (credit Mysteries Department and link the page)  

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[Bloop and NOAA's unexplained ocean sounds](https://mysteriesdept.com/mysteries/noaa-ocean-sounds)Evidence

Evidence · Bloop and NOAA's unexplained ocean sounds

# Upsweep peaks in spring and autumn, which may reflect either the source or seasonal propagation.

Upsweep peaks in spring and autumn, which may reflect either the source or seasonal propagation.

Speculative0

## What it bears on 1 answer

[Upsweep is an ice sound, its seasonality driven by the annual cycle of iceberg drift and breakup.](https://mysteriesdept.com/mysteries/noaa-ocean-sounds/answers/ANS0D9C7MKR0P6H/upsweep-is-an-ice-sound-its-seasonality-driven-by-the-annual)

Still possible

FOR

## Cite it

```
Mysteries Department. (2026). Upsweep peaks in spring and autumn, which may reflect either the source or seasonal propagation. [Evidence EVD0D9C7N3C1XRY]. https://mysteriesdept.com/r/EVD0D9C7N3C1XRY
```

Key

**EVD** 0D9C7N3C1XRY

Kind

Evidence

Tier

Speculative

Version

1

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