MPL terrain (NCL)

Summary

MPL terrain (NCL) is a sequential colormap from ncar. Lightness spans 0.40–1.00, hue sweeps 274° from violet to orange, and order breaks under protan, deutan, and tritan simulation.

NCL terrain port.

Perceptual profile (OKLCh)

• Lightness: 0.397 → 1.000 (range 0.603, min 0.397, max 1.000); non-monotonic; midpoint 0.974
• Chroma: min 0.000, max 0.197, mean 0.107
• Hue: 274.5° → 0.0° (span 274.5°), path monotonic-ccw; quadrants: violet, blue, azure, cyan, mint, green, chartreuse, yellow, orange
• Endpoint temperature: cool → null
• Perceptual ΔE: total 219.2, mean/step 0.860, max step 3.846, smoothness 0.325, speed 0.860

Colorblind safety (ΔE under simulated CVD)

• Protanopia: ΔE total 196.3; preserves order: no
• Deuteranopia: ΔE total 190.5; preserves order: no
• Tritanopia: ΔE total 185.2; preserves order: no

Related

• Family: ncar
• Source: NCL/NCAR — UCAR (via hhuangwx/cmaps MIT wrapper)
• Similar sequential maps: NCL CBR drywet, NCL CBR wet, GMT drywet, GMT topo, NCL precip 15lev, NCL temp 19lev, NCL topo 15lev, NCL wind 17lev
• All colormaps