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Abstract Comparisons of high‐resolution extended range CCN spectra measured at 100 m altitude with cloud and drizzle microphysics in the Rain in Cumulus over the Ocean (RICO) aircraft field project are presented. CCN concentrations,N_CCN, active at supersaturations,S, >0.1% showed positive relationships with cloud droplet concentrations,N_c, measured at intermediate (606–976 m) and very high altitudes (1,763–3,699 m). These correlation coefficients,R, progressively increased withSwhile the two‐tailed probabilities, P2, progressively decreased with S to < 10⁻⁶at 1.6%S. More important were the positive relationships betweenN_CCNactive atS < 0.1% and drizzle drop concentrations,N_d, at high (977–1,662 m), very high and high‐very high altitudes combined (977–3,699 m). All of these relationships were consistent for eight different cloud liquid water content,L_c, thresholds (forN_c) andL_cbins (forN_d) ranging from 0.0002 to 0.3 g/m³. Negative relationships between CCN modality and low altitude (76–475 m) cloudiness coupled with no relationship ofN_CCNactive at any S withN_cof these low clouds indicated a cloud effect on ambient aerosol. This is a demonstration of clouds causing bimodal aerosol. 

Abstract Climate change is leading to species redistributions. In the tundra biome, shrubs are generally expanding, but not all tundra shrub species will benefit from warming. Winner and loser species, and the characteristics that may determine success or failure, have not yet been fully identified. Here, we investigate whether past abundance changes, current range sizes and projected range shifts derived from species distribution models are related to plant trait values and intraspecific trait variation. We combined 17,921 trait records with observed past and modelled future distributions from 62 tundra shrub species across three continents. We found that species with greater variation in seed mass and specific leaf area had larger projected range shifts, and projected winner species had greater seed mass values. However, trait values and variation were not consistently related to current and projected ranges, nor to past abundance change. Overall, our findings indicate that abundance change and range shifts will not lead to directional modifications in shrub trait composition, since winner and loser species share relatively similar trait spaces. 

This white paper is on the HMCS Firefly mission concept study. Firefly focuses on the global structure and dynamics of the Sun's interior, the generation of solar magnetic fields, the deciphering of the solar cycle, the conditions leading to the explosive activity, and the structure and dynamics of the corona as it drives the heliosphere.