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<p>Although calcium is known to be enriched in sea spray aerosols (SSAs), the factors that affect its enrichment remain ambiguous. In this study, we examine how environmental factors affect the distribution of water-soluble calcium (Ca<span class="inline-formula">²⁺</span>) distribution in SSAs. We obtained our dataset from observations taken during the R/V <i>Xuelong</i> research cruise in the Ross Sea, Antarctica, from December 2017 to February 2018. Our observations showed that the enrichment of Ca<span class="inline-formula">²⁺</span> in aerosol samples was enhanced under specific conditions, including lower temperatures (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>&lt;</mo><mo>-</mo><mn mathvariant="normal">3.5</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="35pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="a02a53301a96bb7892434dbbb5a8930d"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="acp-23-10697-2023-ie00001.svg" width="35pt" height="10pt" src="acp-23-10697-2023-ie00001.png"/></svg:svg></span></span> <span class="inline-formula">^∘</span>C), lower wind speeds (<span class="inline-formula">&lt;7</span> m s<span class="inline-formula">⁻¹</span>), and the presence of sea ice. Our analysis of individual particle mass spectra revealed that a significant portion of calcium in SSAs was likely bound with organic matter (in the form of a single-particle type, OC-Ca, internally mixed organics with calcium). Our findings suggest that current estimations of Ca<span class="inline-formula">²⁺</span> enrichment based solely on water-soluble Ca<span class="inline-formula">²⁺</span> may be inaccurate. Our study is the first to observe a single-particle type dominated by calcium in the Antarctic atmosphere. Our findings suggest that future Antarctic atmospheric modeling should take into account the environmental behavior of individual OC-Ca particles. With the ongoing global warming and retreat of sea ice, it is essential to understand the mechanisms of calcium enrichment and the mixing state of individual particles to better comprehend the interactions between aerosols, clouds, and climate during the Antarctic summer.</p>