Research Highlights

TOA Radiation Budget of Convective Core/Stratiform Rain/Anvil Clouds from Deep Convection
Jan 30, 2012
Deep Convective Systems (DCSs) have traditionally been divided into the deep convective precipitating portion and the non-precipitating anvil canopy. The former is important to the atmospheric hydrologic cycle because of the heavy precipitation in the convective cores (CC) and widespread precipitation in the stratiform rain (SR) regions, and the latter are dominant in the [...]

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What Exactly Do Metrics for Aerosol-Cloud Interactions Represent?
Jan 24, 2012
The interaction of aerosols and clouds engenders a large measure of uncertainty in climate sensitivity and climate change. Metrics that quantify these interactions and associated radiative forcing estimates span a range that is too wide to be definitive for climate studies. We argue that a component of this uncertainty derives from the use of a [...]

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Predicting Arctic Sea Ice Loss
Jan 14, 2012
Arctic clouds are strongly tied to Arctic sea ice loss. To find the strength of those ties, a team led by scientists at Pacific Northwest National Laboratory tested a prominent climate model with observed data and found that it significantly underestimates liquid water content in the Arctic single-layer mixed-phase clouds, which affect how much solar [...]

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Trends in Downwelling Longwave Radiation over SGP
Jan 05, 2012
The long-term measurements that are being collected at the ARM Climate Research Facility sites provide a unique data set that can be used to look at trends in the atmospheric state or composition. While the ARM data record is too short for any trends to be considered as trends in climate, any trends do [...]

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Case Closed on Nauru Island Effect
Jan 05, 2012
The tiny 4-kilometer-by-6-kilometer island of Nauru is isolated in the equatorial Pacific Ocean with naught but a few small scattered islands for thousands of kilometers around. Thus, the ARM measurements made there are intended to represent the larger surrounding oceanic area. But decades of phosphate mining have left large barren karst fields as the predominant [...]

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The Long-Term Impacts of Aerosols on the Vertical Development of Clouds and Precipitation
Dec 29, 2011
Aerosols—tiny particles in the air, like dust or soot—can affect clouds and precipitation by serving as cloud condensation nuclei (CCN), altering cloud microphysics and precipitation processes and modulating radiative and latent energy to change atmospheric dynamics and thermodynamics that dictate cloud development. These effects can either suppress or foster cloud and precipitation processes. Various effects [...]

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Unraveling the Complexity of Arctic Mixed-Phase Clouds
Dec 23, 2011
The Arctic is particularly sensitive to climate change, with potentially dramatic consequences for the regional ecosystem. Arctic mixed-phase clouds, comprising both ice and supercooled liquid water, have been observed to occur frequently in all seasons and persist for many days at a time. They have a large impact on the shortwave and longwave radiative transfer [...]

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Mixed-Phase Cloud Radiative Properties from M-PACE Microphysical Retrievals
Dec 06, 2011
Mixed-phase stratiform clouds have been demonstrated to be a major contributor to the surface radiative budget of the Arctic. Measurements of these clouds and the associated surface radiative flux densities are expanding. In this work, we utilize a variety of cloud and atmospheric measurements to derive the macro- and microphysical properties of mixed-phase [...]

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A Dance of Aerosols
Dec 06, 2011
In the complex molecular mixer that is the atmosphere, some molecules dance with others and some are wallflowers, according to DOE scientists at Pacific Northwest National Laboratory. The scientists focused on how a specific vapor, responsible for the aromatic scent of fir trees, forms carbon-containing particles that mix with certain carbon-containing acids in the atmosphere. [...]

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