In 2002, Dwyer and collaborators discovered that rocket-triggered lightning produced large quantities of x-rays, allowing for first the time detailed studies of an atmospheric phenomenon known as runaway breakdown.

[7] Dwyer also has made several important theoretical contributions to the newly developing field of High Energy Atmospheric Physics, including work on runaway electron or runaway breakdown physics,[8] gamma-ray and radio frequency emissions or atmospheric noise,[3][9] and lightning initiation.

[8] In 2003, he introduced the Relativistic Feedback Mechanism of relativistic-runaway-electron avalanches,[10] a new discharge mechanism in air, which explains how thunderclouds may generate very large flashes of gamma-rays called terrestrial gamma-ray flashes (TGFs).

Working with David Smith from UCSC he also helped establish that TGFs originate from deep within our atmosphere and not at high altitudes as had been previously assumed.

[12] Finally, using BATSE data from the Compton Gamma-ray Observatory, Dwyer and collaborators discovered Terrestrial Electron Beams (TEBs) [13] in the inner magnetosphere, which are generated by the high energy emissions from thunderstorms.