Micro- (<5mm diameter) and nano-plastics (1nm-1 μm diameter) are ubiquitous pollutants to aquatic and terrestrial environments and these particles can be transported long distances through the atmosphere. While not fully understood, microplastics are potentially detrimental to the health of humans and animals. This study compares atmospheric microplastic particles (AMP) concentrations collected from air samples over terrestrial and coastal regions in California: Lake Tahoe and Monterey Bay, respectively. Atmospheric total suspended particulate matter was collected weekly at the three site locations and AMP concentration in samples from 2006 to 2023 were determined using flow cytometry to quantify concentrations and track changes in plastic particle abundance over time. NOAA HYSPLIT back trajectories are used to infer probable AMP source regions. The coastal sites of Santa Cruz and Elkhorn Slough Reserve are proximal to different land usage with similar distances to the coast. Lake Tahoe is 285 km from the ocean and an altitude of 1897 m. Lake Tahoe samples recorded an average concentration of 2.39 particles m-3 from 2005-2006 and 1.83 particles m-3 from January-October 2009. Elkhorn Slough Reserve recorded an average concentration of 4.56 particles m-3. Samples collected before and after a large wildfire at the Santa Cruz Mountains were also compared. Santa Cruz recorded an average of 8.44 particles m-3 prior to the CZU fire complex, 17.59 particles m-3 during and 4.93 particles m-3 directly after. Higher AMP concentrations at all three sites correspond to long range transport with local and regional (urban, wildfire) influence. This study aims to detect AMP in locations with varying proximity to the ocean and land use in hopes to draw awareness about how long-range transport of AMP is affecting the environment and subsequently the public’s health.