Publications by authors named "Sajeev Philip"

La Niña climate anomalies have historically been associated with substantial reductions in the atmospheric CO growth rate. However, the 2021 La Niña exhibited a unique near-neutral impact on the CO growth rate. In this study, we investigate the underlying mechanisms by using an ensemble of net CO fluxes constrained by CO observations from the Orbiting Carbon Observatory-2 in conjunction with estimates of gross primary production and fire carbon emissions.

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Land carbon sink is a vital component for the achievement of China's ambitious carbon neutrality goal, but its magnitude is poorly known. Atmospheric observations and inverse models are valuable tools to constrain the China's land carbon sink. Space-based CO measurements from satellites form an emerging data stream for application of such atmospheric inversions.

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Exposure to ambient fine particulate matter (PM) is a leading risk factor for the global burden of disease. However, uncertainty remains about PM sources. We use a global chemical transport model (GEOS-Chem) simulation for 2014, constrained by satellite-based estimates of PM to interpret globally dispersed PM mass and composition measurements from the ground-based surface particulate matter network (SPARTAN).

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India is currently experiencing degraded air quality, and future economic development will lead to challenges for air quality management. Scenarios of sectoral emissions of fine particulate matter and its precursors were developed and evaluated for 2015-2050, under specific pathways of diffusion of cleaner and more energy-efficient technologies. The impacts of individual source sectors on PM concentrations were assessed through systematic simulations of spatially and temporally resolved particulate matter concentrations, using the GEOS-Chem model, followed by population-weighted aggregation to national and state levels.

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Most studies on the association between exposure to fine particulate matter (PM2.5) and mortality have considered only total concentration of PM2.5 or individual components of PM2.

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Epidemiologic and health impact studies are inhibited by the paucity of global, long-term measurements of the chemical composition of fine particulate matter. We inferred PM2.5 chemical composition at 0.

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