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Abstract. In a joint NRL/Manila Observatory mission, as part of the Seven SouthEast Asian Studies program (7-SEAS), a 2-week, late September 2011 research cruise in the northern Palawan archipelago was undertaken to observe the nature of southwest monsoonal aerosol particles in the South China Sea/East Sea (SCS/ES) and Sulu Sea region. Previous analyses suggested this region as a receptor for biomass burning from Borneo and Sumatra for boundary layer air entering the monsoonal trough. Anthropogenic pollution and biofuel emissions are also ubiquitous, as is heavy shipping traffic. Here, we provide an overview of the regional environment during the cruise, a time series of key aerosol and meteorological parameters, and their interrelationships. Overall, this cruise provides a narrative of the processes that control regional aerosol loadings and their possible feedbacks with clouds and precipitation. While 2011 was a moderate El Niño-Southern Oscillation (ENSO) La Niña year, higher burning activity and lower precipitation was more typical of neutral conditions. The large-scale aerosol environment was modulated by the Madden-Julian Oscillation (MJO) and its associated tropical cyclone (TC) activity in a manner consistent with the conceptual analysis performedPublished by Copernicus Publications on behalf of the European Geosciences Union. J. S. Reid et al.: Temporal variability in South Chinas Sea aerosol propertiesby Reid et al. (2012). Advancement of the MJO from phase 3 to 6 with accompanying cyclogenesis during the cruise period strengthened flow patterns in the SCS/ES that modulated aerosol life cycle. TC inflow arms of significant convection sometimes span from Sumatra to Luzon, resulting in very low particle concentrations (minimum condensation nuclei CN < 150 cm −3 , non-sea-salt PM 2.5 < 1 µg m −3 ). However, elevated carbon monoxide levels were occasionally observed suggesting passage of polluted air masses whose aerosol particles had been rained out. Conversely, two drier periods occurred with higher aerosol particle concentrations originating from Borneo and Southern Sumatra (CN > 3000 cm −3 and non-sea-salt PM 2.5 10-25 µg m −3 ). These cases corresponded with two different mechanisms of convection suppression: lower free-tropospheric dry-air intrusion from the Indian Ocean, and large-scale TC-induced subsidence. Veering vertical wind shear also resulted in aerosol transport into this region being mainly in the marine boundary layer (MBL), although lower free troposphere transport was possible on the western sides of Sumatra and Borneo. At the hourly time scale, particle concentrations were observed to be modulated by integer factors through convection and associated cold pools. Geostationary satellite observations suggest that convection often takes the form of squall lines, which are bowed up to 500 km across the monsoonal flow and 50 km wide. These squall lines, initiated by cold pools from large thunderstorms and likely sustained by a veering vertical wind shear and aforementioned mid-troposphere dr...

Proanthocyanidins (PAs) are oligomeric flavonoids and one group of end products of the phenylpropanoid pathway. PAs have been reported to be beneficial for human and animal health and are particularly important in pastoral agricultural systems for improved animal production and reduced greenhouse gas emissions. However, the main forage legumes grown in these systems, such as Trifolium repens and Medicago sativa, do not contain any substantial amounts of PAs in leaves. We have identified from the foliar PA-accumulating legume Trifolium arvense an R2R3-MYB transcription factor, TaMYB14, and provide evidence that this transcription factor is involved in the regulation of PA biosynthesis in legumes. TaMYB14 expression is necessary and sufficient to up-regulate late steps of the phenylpropanoid pathway and to induce PA biosynthesis. RNA interference silencing of TaMYB14 resulted in almost complete cessation of PA biosynthesis in T. arvense, whereas Nicotiana tabacum, M. sativa, and T. repens plants constitutively expressing TaMYB14 synthesized and accumulated PAs in leaves up to 1.8% dry matter. Targeted liquid chromatography-multistage tandem mass spectrometry analysis identified foliar PAs up to degree of polymerization 6 in leaf extracts. Hence, genetically modified M. sativa and T. repens plants expressing TaMYB14 provide a viable option for improving animal health and mitigating the negative environmental impacts of pastoral animal production systems.

[1] Numerous high-resolution (1 km or better) images from satellite remote sensing platforms, i.e., space shuttle, Sea-viewing Wide Field-of-view Sensor, and the Moderate Resolution Imaging Spectroradiometer, show dust plumes at the scale of 100 km originate from the merging of a multitude of point source plumes. These point source plumes stem from numerous point sources measuring 1-10s km across. Capitalizing on the Naval Research Laboratory's recently developed satellite derived 1-km Dust Enhancement Product (DEP) imagery we can readily distinguish elevated dust over land from other components of the scene and identify the many small, eroding point sources that form the heads of point source plumes. On the basis of this approach, a high-resolution (1-km) dust source database (DSD) is created using 5 years (2001)(2002)(2003)(2004)(2005) of DEP imagery for southwest Asia. The performance of the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) using the high-resolution DSD is evaluated via a case study of a major dust event over Afghanistan, Iran, and Pakistan in October 2001. The results from our case study show that the improved specification of erodible land surfaces by use of a high-resolution DSD allows COAMPS to accurately model the evolution of individual dust plumes and better forecast the onset and end of dust storm occurrence (i.e., low-visibility conditions). Statistical analyses of the visibility predictions and dust storm occurrence show simulations using the high-resolution DSD have the lowest false alarm rates and the highest total prediction skill among the other DSDs that were considered. This work contributes to the growing base of knowledge concerning the global dust cycle by identifying and mapping point sources in one of the world's foremost dust-producing regions.

Since August 2000, the Wild fire Automated Biomass Burning Algorithm (WF_ABBA) has been generating half‐hourly fire hot spot analyses for the Western Hemisphere using GOES satellites to provide the Naval Research Laboratory (NRL) Aerosol Analysis and Prediction System (NAAPS) with near‐real‐time fire products. These are used to generate smoke particle fluxes for aerosol transport forecasting to benefit the scientific, weather, and regulatory communities. In South America, fire hot‐spot analysis is shown to be adequate for generating real‐time smoke source functions for aerosol forecast models. We present smoke coverage and flux estimates based on the WF_ABBA and NAAPS products. Modeled fluxes of emissions for 2001–2002 are ∼25 + 10 Tg yr−1, similar to previous estimates. Correlations of optical depth with MODIS and AERONET show good agreement with observations. Comparisons of NAAPS aerosol fields with MODIS also show potential clear sky and other biases as smoke is transported into the Atlantic Ocean and the ITCZ.