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Rather than coasting on that success, the enigmatic Ride led several more lives - as a physicist, investigator of the Challenger and Columbia shuttle disasters and tireless advocate for science education - gaining the respect and affection of her colleagues along the way. Instruments on NASA satellites confirmed the existence of the polar ozone holes, made the first global measurements of atmospheric aerosols and have monitored ice-sheet melting and rising sea levels.

The year 2013 also marked the 50th anniversary of this award, first instituted by President John F. Kennedy in 1963, as the nation's highest civilian honor, \"presented to individuals who have made especially meritorious contributions to the security or national interests of the United States, to world peace, or to cultural or other significant public or private endeavors.\"

While most large-scale smoke advection occurs within the free troposphere, Maritime Continent smoke is suspected to be unique in its long-range, near-surface transport. Such a pathway likely creates strong gradients and uncertainties in interpreting satellite and model data on light extinction, air pollution, and cloud condensation nuclei. This paper documents High Spectral Resolution Lidar (HSRL) data from the 2019 ONR PISTON cruise and NASA CAMP2Ex flights that revealed Maritime Continent smoke and pollution transport pathways and heterogeneity around the Marine Atmospheric Boundary Layer (MABL) over thousands of kilometers. Observations showed that 95 % of integrated aerosol backscatter occurred below 2500 m altitude. The R/V Sally Ride observed 50th and 84th percentile aerosol backscatter altitudes at ∼600 and ∼1500 m respectively, regardless of aerosol loading. Peak backscatter values occurred within or near the MABL top, diminishing as we approached 2–3 km altitude, but with occasional plumes reaching the melting level at 4800 m. At monsoonal scales, aerosol models largely account for the observed directional wind shear that causes altitude-dependent particle transport: near-surface particles remain in the core monsoon flow around the MABL, while at lower latitudes, aerosol layers aloft advect more eastwardly. Around the MABL, however, significant cloud-scale variability exists due to fine-scale flow, halo-entrainment-detrainment, and cold pool phenomena. Backscatter enhancements beneath individual clouds, extending to the ocean surface, likely relate to MABL-free troposphere exchange and air-sea interaction. So while aerosol transport occurs near the surface, particle extinction heterogeneity must still be considered for in situ observations and satellite retrievals.

Sally Ride was one of the first six women to enter NASA's astronaut program. On June 18, 1983, the space shuttle Challenger launched into space with Ride aboard. She became the first American woman in space, and at 32 years old, the youngest American.

Source functions for mechanically driven coarse-mode sea spray and dust aerosol particles span orders of magnitude owing to a combination of physical sensitivity in the system and large measurement uncertainty. Outside special idealized settings (such as wind tunnels), aerosol particle fluxes are largely inferred from a host of methods, including local eddy correlation, gradient methods, and dry deposition methods. In all of these methods, it is difficult to relate point measurements from towers, ships, or aircraft to a general representative flux of aerosol particles. This difficulty is from the particles' inhomogeneous distribution due to multiple spatiotemporal scales of an evolving marine environment. We hypothesize that the current representation of a point in situ measurement of sea spray or dust particles is a likely contributor to the unrealistic range of flux and concentration outcomes in the literature. This paper aims to help the interpretation of field data: we conduct a series of high-resolution, cloud-free large eddy simulations (LESs) with Lagrangian particles to better understand the temporal evolution and volumetric variability of coarse- to giant-mode marine aerosol particles and their relationship to turbulent transport. The study begins by describing the Lagrangian LES model framework and simulates flux measurements that were made using numerical analogs to field practices such as the eddy covariance method. Using these methods, turbulent flux sampling is quantified based on key features such as coherent structures within the marine atmospheric boundary layer (MABL) and aerosol particle size. We show that for an unstable atmospheric stability, the MABL exhibits large coherent eddy structures, and as a consequence, the flux measurement outcome becomes strongly tied to spatial length scales and relative sampling of crosswise and streamwise sampling. For example, through the use of ogive curves, a given sampling duration of a fixed numerical sampling instrument is found to capture 80 % of the aerosol flux given a sampling rate of zf/w∗∼ 0.2, whereas a spanwise moving instrument results in a 95 % capture. These coherent structures and other canonical features contribute to the lack of convergence to the true aerosol vertical flux at any height. As expected, sampling all of the flow features results in a statistically robust flux signal. Analysis of a neutral boundary layer configuration results in a lower predictive range due to weak or no vertical roll structures compared to the unstable boundary layer setting. Finally, we take the results of each approach and compare their surface flux variability: a baseline metric used in regional and global aerosol models.

New production (NP) and net community production (NCP) measurements are often used as estimates of carbon export potential from the mixed layer of the ocean, an important process in the regulation of global climate. Diverse methods can be used to measure NP and NCP, from research vessels, autonomous platforms, and remote sensing, each with its own set of benefits and uncertainties. The various methods are rarely applied simultaneously in a single location, limiting our ability for direct comparisons of the resulting measurements. In this study, we evaluated NP and NCP from thirteen independent datasets collected via in situ, in vitro, and satellite-based methods near Ocean Station Papa during the 2018 Northeast Pacific field campaign of the NASA project EXport Processes in the Ocean from RemoTe Sensing (EXPORTS). Altogether, the datasets indicate that carbon export potential was relatively low (median daily averages between −5.1 and 12.6 mmol C m−2 d−1), with most measurements indicating slight net autotrophy in the region. This result is consistent with NCP estimates based on satellite measurements of sea surface temperature and chlorophyll a. We explored possible causes of discrepancies among methods, including differences in assumptions about stoichiometry, vertical integration, total volume sampled, and the spatiotemporal extent considered. Results of a generalized additive mixed model indicate that the spatial variation across platforms can explain much of the difference among methods. Once spatial variation and temporal autocorrelation are considered, a variety of methods can provide consistent estimates of NP and NCP, leveraging the strengths of each approach.

Late Pleistocene–Holocene rocks from the western part of Cocos-Nazca Spreading Centre (C-NSC) include ferromanganese crusts that elucidate the geochemistry and mineralogy of a deep-sea geological setting. Six representative Fe-Mn crust samples were studied using petrological methods, such as optical transmitted light microscopy, energy dispersive X-ray fluorescence spectrometry, inductively coupled plasma mass spectrometry, bulk X-ray diffraction, scanning electron microscopy and electron probe microanalysis. Geochemical, mineralogical and petrological signatures indicate complex formation influenced by mild hydrothermal processes. These crusts consist mostly of mixed birnessite, todorokite-buserite, and Mn-(Fe) vernadite with traces of diagenetic manganates (asbolane), Fe-oxides and oxyhydroxides or hydrothermally associated and relatively pure Mn-oxyhydroxides (manganite). The average Mn/Fe ratio is 2.7, which suggests predominant mixed hydrogenous-early diagenetic crusts with hydrothermal influences. The mean concentrations of three prospective metals (Ni, Cu and Co) are low: 0.17, 0.08 and 0.025 wt %, respectively. The total content of ΣREY is also low, and ranges from 81 to 741 mg/kg (mean 339 mg/kg). We interpret the complex geochemical and mineralogical data to reflect mixed origin of the crusts, initially related with formation of hydrothermal plume over the region. This process occurred during further interactions with seawater from which additional diagenetic and hydrogenetic elemental signatures were acquired.