System for &amp;lt;i&amp;gt;δ&amp;lt;/i&amp;gt;&amp;lt;sup&amp;gt;13&amp;lt;/sup&amp;gt;C–CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; and &amp;lt;i&amp;gt;x&amp;lt;/i&amp;gt;CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; analysis of discrete gas samples by cavity ring-down spectroscopy
Atmospheric measurement techniques