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<p><span id="page8894"/>This study investigates the rain-initiated mixing and variability in the mixing ratio of selected trace gases in the atmosphere over the central Amazon rain forest. It builds on comprehensive data from the Amazon Tall Tower Observatory (ATTO), spanning from 2013 to 2020 and comprising the greenhouse gases (GHGs) carbon dioxide (<span class="inline-formula">CO₂</span>) and methane (<span class="inline-formula">CH4</span>); the reactive trace gases carbon monoxide (<span class="inline-formula">CO</span>), ozone (<span class="inline-formula">O₃</span>), nitric oxide (<span class="inline-formula">NO</span>), and nitrogen dioxide (<span class="inline-formula">NO₂</span>); and selected volatile organic compounds (VOCs). Based on more than 1000 analyzed rainfall events, the study resolves the trace gas mixing ratio patterns before, during, and after the rain events, along with vertical mixing ratio gradients across the forest canopy. The assessment of the rainfall events was conducted independently for daytime and nighttime periods, which allows us to elucidate the influence of solar radiation. The mixing ratios of <span class="inline-formula">CO₂</span>, <span class="inline-formula">CO</span>, and <span class="inline-formula">CH₄</span> clearly declined during rainfall, which can be attributed to the downdraft-related entrainment of pristine air from higher altitudes into the boundary layer, a reduction of the photosynthetic activity under increased cloud cover, and changes in the surface fluxes. Notably, <span class="inline-formula">CO</span> showed a faster reduction than <span class="inline-formula">CO₂</span>, and the vertical gradient of <span class="inline-formula">CO₂</span> and <span class="inline-formula">CO</span> is steeper than for <span class="inline-formula">CH₄</span>. Conversely, the <span class="inline-formula">O₃</span> mixing ratio increased across all measurement heights in the course of the rain-related downdrafts. Following the <span class="inline-formula">O₃</span> enhancement by up to a factor of 2, <span class="inline-formula">NO</span>, <span class="inline-formula">NO₂</span>, and isoprene mixing ratios decreased. The temporal and vertical variability of the trace gases is intricately linked to the diverse sink and source processes, surface fluxes, and free-troposphere transport. Within the canopy, several interactions unfold among soil, atmosphere, and plants, shaping the overall dynamics. Also, the mixing ratio of biogenic VOCs (BVOCs) clearly varied with rainfall, driven by factors such as light, temperature, physical transport, and soil processes.</p> <p>Our results disentangle the patterns in the trace gas mixing ratio in the course of sudden and vigorous atmospheric mixing during rainfall events. By selectively uncovering processes that are not clearly detectable under undisturbed conditions, our results contribute to a better understanding of the trace gas life cycle and its interplay with meteorology, cloud dynamics, and rainfall in the Amazon.</p>