Oceans cover over two-thirds of the Earth's surface, and the particles emitted to the atmosphere by waves breaking on sea surfaces provide an important contribution to the planetary albedo. During the International Chemistry Experiment in the Arctic LOwer Troposphere (ICEALOT) cruise on the R/V Knorr in March and April of 2008, organic mass accounted for 15-47% of the submicron particle mass in the air masses sampled over the North Atlantic and Arctic Oceans. A majority of this organic component (0.1 − 0.4 μ m −3 ) consisted of organic hydroxyl (including polyol and other alcohol) groups characteristic of saccharides, similar to biogenic carbohydrates found in seawater. The large fraction of organic hydroxyl groups measured during ICEALOT in submicron atmospheric aerosol exceeded those measured in most previous campaigns but were similar to particles in marine air masses in the open ocean (Southeast Pacific Ocean) and coastal sites at northern Alaska (Barrow) and northeastern North America (Appledore Island and Chebogue Point). The ocean-derived organic hydroxyl mass concentration during ICEALOT correlated strongly to submicron Na concentration and wind speed. The observed submicron particle ratios of marine organic mass to Na were enriched by factors of ∼10 2 -∼10 3 over reported sea surface organic to Na ratios, suggesting that the surface-controlled process of film bursting is influenced by the dissolved organic components present in the sea surface microlayer. Both marine organic components and Na increased with increasing number mean diameter of the accumulation mode, suggesting a possible link between organic components in the ocean surface and aerosol-cloud interactions.atmospheric aerosol | marine carbohydrates | organic aerosols | sea salt particles

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The accuracy of the estimated radiative forcing of tropospheric sulfate aerosol depends on the quality and spatial coverage of the aerosol chemical, physical, and optical data that serve as input to global climate models. To augment the available data and to provide a comparison of measured and calculated optical properties, surface measurements were made of the aerosol light scattering and backscattering coefficients, the number size distribution from 0.02 to 9.6 μm, and chemical mass size distributions during two Pacific Ocean field experiments. All measurements were made on an aerosol sample stream dried to 30% relative humidity and are reported as such. The first experiment took place during the Pacific Sulfur/Stratus Investigation at Cheeka Peak, Washington, in April and May of 1991 (PSI 91). The second occurred as part of the Marine Aerosol and Gas Exchange cruise in February and March of 1992 (MAGE 92) which was conducted from 33°N to 12°S along 140°W. The mass size distributions of nonseasalt sulfate and sodium varied widely both spatially and temporally. The shape of the number size distribution remained fairly constant throughout both experiments with an accumulation mode geometric number mean diameter of 0.19±0.03 μm and a geometric mean standard deviation of 1.4 ± 0.06. Measured light scattering and backscattering ranged from 3.7 to 19×10−6 m−1 and 0.64 to 2.8×106 m−1, respectively, resulting in an average backscattered fraction of 0.15 with a standard deviation of ±0.009. The light scattering and backscattering coefficients were calculated from a Mie model applied to the measured number size distributions. The mean of the calculated scattering values was 3% higher than the mean of the measured values with a 14% variance about the mean. This variance was within the uncertainty of the calculations indicating that the scattering characteristics of the aerosol were parameterized adequately by the model. The calculated backscattering values were about 40% lower than the measured values, however. The calculated light scattering apportioned to nonseasalt sulfate aerosol was 39±17% of the total calculated scatter. The scattering to mass ratio for sulfate aerosol averaged 5.0 m2 g−1 with a standard deviation of ±1.6 m2 g−1 and varied with variability in the number size distribution. Further measurements are needed that will allow for the formation of a global‐scale database to reveal the extent of the variability in the aerosol chemical, physical, and optical properties relevant to climate forcing.

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[1] On five occasions spanning the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) field campaign in spring 2001, the Multiangle Imaging Spectroradiometer spaceborne instrument took data coincident with high-quality observations by instruments on two or more surface and airborne platforms. The cases capture a range of clean, polluted, and dusty aerosol conditions. With a three-stage optical modeling process, we synthesize the data from over 40 field instruments into layer-by-layer environmental snapshots that summarize what we know about the atmospheric and surface states at key locations during each event. We compare related measurements and discuss the implications of apparent discrepancies, at a level of detail appropriate for satellite retrieval algorithm and aerosol transport model validation. Aerosols within a few kilometers of the surface were composed primarily of pollution and Asian dust mixtures, as expected. Medium-and coarse-mode particle size distributions varied little among the events studied; however, column aerosol optical depth changed by more than a factor of 4, and the near-surface proportion of dust ranged between 25% and 50%. The amount of absorbing material in the submicron fraction was highest when near-surface winds crossed Beijing and the Korean Peninsula and was considerably lower for all other cases. Having simultaneous single-scattering albedo measurements at more than one wavelength would significantly reduce the JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 109, D19S14,

Background and Purpose: Conditions associated with frailty are common in people experiencing stroke and may explain differences in outcomes. We assessed associations between a published, generic frailty risk score, derived from administrative data, and patient outcomes following stroke/transient ischemic attack; and its accuracy for stroke in predicting mortality compared with other measures of clinical status using coded data. Methods: Patient-level data from the Australian Stroke Clinical Registry (2009–2013) were linked with hospital admissions data. We used International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes with a 5-year look-back period to calculate the Hospital Frailty Risk Score (termed Frailty Score hereafter) and summarized results into 4 groups: no-risk (0), low-risk (1–5), intermediate-risk (5–15), and high-risk (>15). Multilevel models, accounting for hospital clustering, were used to assess associations between the Frailty Score and outcomes, including mortality (Cox regression) and readmissions up to 90 days, prolonged acute length of stay (>20 days; logistic regression), and health-related quality of life at 90 to 180 days (quantile regression). The performance of the Frailty Score was then compared with the Charlson and Elixhauser Indices using multiple tests (eg, C statistics) for predicting 30-day mortality. Models were adjusted for covariates including sociodemographics and stroke-related factors. Results: Among 15 468 adult patients, 15% died ≤90 days. The frailty scores were 9% no risk; 23% low, 45% intermediate, and 22% high. A 1-point increase in frailty (continuous variable) was associated with greater length of stay (OR adjusted , 1.05 [95% CI, 1.04 to 1.06), 90-day mortality (HR adjusted , 1.04 [95% CI, 1.03 to 1.05]), readmissions (OR adjusted , 1.02 [95% CI, 1.02 to 1.03]; and worse health-related quality of life (median difference, −0.010 [95% CI −0.012 to −0.010]). Adjusting for the Frailty Score provided a slightly better explanation of 30-day mortality (eg, larger C statistics) compared with other indices. Conclusions: Greater frailty was associated with worse outcomes following stroke/transient ischemic attack. The Frailty Score provides equivalent precision compared with the Charlson and Elixhauser indices for assessing risk-adjusted outcomes following stroke/transient ischemic attack.

The results show that there is considerable variation in repeated measurements of prostatic volume and the variation is greatest for 2 observers compared to 1 observer.