Vehicle emissions of greenhouse gases and related tracers from a tunnel study: CO : CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;, N&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;O : CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;, CH&amp;lt;sub&amp;gt;4&amp;lt;/sub&amp;gt; : CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt;, O&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; : CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; ratios, and the stable isotopes &amp;lt;sup&amp;gt;13&amp;lt;/sup&amp;gt;C and &amp;lt;sup&amp;gt;18&amp;…
Atmospheric chemistry and physics