# Limb Radiance Infrared Spectrum at 12 km Tangent Height

Graph options

**Limb radiance** at 12 km tangent height is the spectral radiance emerging from the edge of the atmosphere viewed along a line of sight which passes 12 km above the surface, thus excluding any surface emission and the bulk of tropospheric water vapour.

**Spectral radiance** is the radiant flux (electromagnetic energy emitted per unit time) from a surface per unit solid angle per unit area per unit frequency.
The units here are nW/(cm^{2} sr cm^{-1}).

Click on a data series or compound name in the legend to toggle its visibility

Click and drag on the graph to select an area to zoom (pinch to zoom on touchscreens)

Use the scrollbar below the graph to view a different wavelength range

Graphs can be downloaded from the menu at the top left

Click and drag on the graph to select an area to zoom (pinch to zoom on touchscreens)

Use the scrollbar below the graph to view a different wavelength range

Graphs can be downloaded from the menu at the top left