trend 26 27 Significance statement: Terrestrial arthropods, including insects and spiders, serve critical 28 ecosystem functions and are excellent indicators of environmental change due to their physiology, 29 short generation time, and abundance. The Arctic, with its rapid climate change and limited direct 30 anthropogenic impact, is ideal for examining arthropod population dynamics. We use the most 31 comprehensive, standardized dataset available on Arctic arthropods to evaluate the variability in 32 population dynamics for the most common arthropod groups at various taxonomic levels across 24 33 years. Our results highlight that temporal trends of arthropod populations seem less directional in 34 the Arctic than in temperate regions. Although abundances of some arthropod taxa are declining, 35 particularly in recent decades, population trends still display high variation among time periods, 36 taxa, and habitats. 37 38 ABSTRACT 39 Time-series data on arthropod populations are critical for understanding the magnitude, direction, 40 and drivers of abundance changes. However, most arthropod monitoring programs are short-lived 41 and limited in taxonomic resolution and spatial extent. Consequently, variation in population 42 dynamics among taxa and habitats remains poorly understood. Monitoring data from the Arctic are 43 particularly underrepresented, yet important to assessments of species abundance changes because 44 many anthropogenic drivers of change that are present in other regions are absent in polar regions. 45Here, we utilise 24 years of abundance data from Zackenberg in High-Arctic Greenland, which is 46 the longest running Arctic arthropod monitoring program, to study temporal trends in abundance. 47Despite a strong warming signal in air temperature, we only find evidence of weak temporal trends 48 in arthropod abundances across most taxa. These trends are more pronounced in the most recent 49 decade, with change point analyses suggesting distinct non-linear dynamics within some functional 50 groups such as predators and detritivores. Although the abundances of many taxa were correlated, 51 we detected both positive and negative correlations, suggesting that multiple processes are affecting 52 arthropod populations even in this relatively simple Arctic food web. Finally, we found clear 53 differences among species within single families of arthropods, indicating that an apparent lack of 54 change in abundance at broader taxonomic or functional levels could mask substantial species-55 specific trends. Our results reiterate the need for more basic research into the life-history, ecology, 56 and adaptation of arthropod species to better understand their sensitivity to global changes. 57 58 595