Thermocline is a free mosaic knit square pattern worked in slip-stitch, using six shades of Cascade Heritage fingering weight yarn. Part of the Year of Color 2026 MAL, this square uses a sliding color sequence that moves from pale sky blue through deep navy, with a deliberate reordering of the yarns about a third of the way up to explore how the same colors read differently in a new sequence.

The mosaic technique works one color at a time. Slipped stitches carry the resting color through the fabric, creating a woven, textured look that’s much simpler to knit than it appears. The square is worked flat.

The name comes from oceanography: a thermocline is the boundary layer where warm surface water meets the cold depths below. That’s exactly what this square does in yarn.

• 5781 Clear Sky
• 5630 Anis
• 5745 Riviera Heather
• 5604 Denim
• 5637 Cerulean
• 5603 Marine