# NCL temp diff 18lev

Canonical URL: https://colorcurio.us/colormaps/ncar.temp_diff_18lev
Source type: Colormap
Type: diverging
Collection: ncar
Attribution: NCL/NCAR — UCAR (via hhuangwx/cmaps MIT wrapper)
License: MIT (wrapper) / public-domain (data)
Source: https://raw.githubusercontent.com/hhuangwx/cmaps/master/cmaps/colormaps/ncar_ncl/temp_diff_18lev.rgb
Tags: diverging, climate, anomaly
Stops: 256

## Summary

NCL temp diff 18lev is a diverging colormap from the ncar collection. Inspect its perceptual lightness, chroma, and hue profile on colorcurio.us.

NCAR standard temperature anomaly.

## Perceptual profile (OKLCh)

- Lightness: 0.245 → 0.305 (range 0.754, min 0.245, max 0.998); non-monotonic; midpoint 0.998
- Chroma: min 0.001, max 0.218, mean 0.113
- Hue: 260.5° → 29.2° (span 186.2°), path folded; quadrants: blue, azure, red, orange
- Endpoint temperature: cool → warm
- Perceptual ΔE: total 174.2, mean/step 0.683, max step 1.150, smoothness 0.747, speed 0.683

## Colorblind safety (ΔE under simulated CVD)

- Protanopia: ΔE total 154.1; preserves order: yes
- Deuteranopia: ΔE total 155.8; preserves order: yes
- Tritanopia: ΔE total 175.2; preserves order: yes

## Related

- Family: https://colorcurio.us/colormaps/families/ncar
- All colormaps: https://colorcurio.us/colormaps