Atmospheric Science Program (ASP) – Climate Forcing: The Effects of Aerosols
2010-BNL-EE025EECA-Budg [KP1205030]
P.I.: Peter H. Daum

In order to better quantify the effects of aerosols on climate, the Department of Energy (DOE) ASP is focused on process studies that follow the life cycle of aerosols and their impacts on the earth's radiative budget. This work is motivated by the Intergovernmental Panel on Climate Change’s finding that aerosol–climate interactions have the most uncertainty of any of the climate forcing factors. ASP’s overall goal is to develop physically-based descriptions of the concentrations and properties of aerosols in the ambient atmosphere suitable for incorporation in regional and global climate models. The complexity of atmospheric aerosols and the current state of knowledge demands a multi-pronged approach to understanding their formation processes, composition, lifetimes, interactions with solar radiation, and their effects on clouds. Such information is needed for major aerosol types as functions of location and atmospheric conditions. Work within the Atmospheric Sciences Division (ASD) at Brookhaven National Laboratory (BNL), covered in this Field Work Proposal (FWP), consists of atmospheric measurements, instrument development, laboratory studies, data dissemination, model calculations, and educational outreach. There are strong interactions between components. A separate FWP covers the activities of the ASP Chief Scientist.

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Chief Scientist for the Atmospheric Science Program
2010-BNL-EE533EECA-Budg [KP1205030]
P.I.: Stephen E. Schwartz

In recognition of the importance of aerosol-radiative forcing of climate change, the Department of Energy (DOE) is focusing research efforts in the Atmospheric Science Program (ASP) to improve understanding and model-based representation of the processes controlling aerosol loading, distribution, and physical and chemical properties relevant to the influence of aerosols on climate. This project consists of the activities of the Chief Scientist for the ASP. The Chief Scientist provides: Scientific leadership and vision to this program and enhances, facilitates, and promotes application of the research conducted in this program; provides leadership and guidance to program participants regarding the direction and course of the science conducted in the program; draws generalizations and conclusions from the work as reflected in the measurements and model calculations of the several investigators; represents this program in the broader national and international arena of climate change research; facilitates communication among program participants, regularly interacts with the DOE Program Managers responsible for ASP to assure that the program is meeting the needs and expectations of DOE and to convey Program activities, accomplishments, and requirements to these Program Managers; and, arranges and leads meetings of the ASP Science Team and others, and of smaller groups as required. The Chief Scientist is also responsible for maintaining the program website.

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Aerosol and Cloud Process Effects in Climate Forcing
2010-BNL-EE612EECA-Budg [KP1205010]
P.I.: Robert L. McGraw

Clouds and the impact of aerosols on the radiative properties of clouds are important issues for the Atmospheric Radiation Measurement (ARM) Program that require accurate representation in climate models. Small changes in the amount, height, thickness, and microphysical properties of clouds due to human influences can exert changes in the Earth’s radiation budget that are comparable to or greater than the radiative forcing by anthropogenic greenhouse gases. Changes in the amount and/or composition of aerosols affect clouds in a variety of ways, and the large uncertainties arise in aerosol-cloud interactions and their impact on radiation balance because key microphysical processes controlling these interactions are not well understood. The interdisciplinary research described here seeks to quantify microphysical and bulk macroscopic processes of clouds over multiple spatial scales, and the meteorological states and dynamical processes that govern them. Focus areas for study include aerosol direct and indirect effects on radiative forcing and parameterizations of relevant microphysical processes. Comprehensive studies integrating theory, modeling, and multiple observations from in situ (e.g., aircraft) and remote sensing (radar) will be conducted to investigate the microphysical, radiative, and dynamical properties of clouds. These will be used to address key issues regarding the treatment of clouds in climate models, and to enhance the interface between ARM observations and models. Coordinated analysis of measurements collected at ARM sites and during ARM field campaigns will be used to advance understanding and quantification of aerosol-cloud interaction, cloud properties, and dynamical conditions that underlie atmospheric radiative processes and climate forcing. The proposed research will meet ARM objectives by improving overall understanding of how aerosol-cloud direct and indirect effects affect the Earth's radiant-energy balance and by quantifying the degree to which changes in cloud properties offset the positive forcing from greenhouse gases.

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Chief Scientist for the DOE Atmospheric Radiation Measurement (ARM) Program
EE-618-EECA [KP1205010]
P.I.: Warren J. Wiscombe

This proposal outlines the duties and responsibilities of the Atmospheric Radiation Measurement (ARM) Program Chief Scientist and team. Externally, the Chief Scientist Team interacts with the larger climate modeling and Earth observation communities. A critical goal of the ARM Program is to improve the representation of clouds and radiation in Global Climate Models (GCMs). Toward that end, the ARM Chief Scientist Team is actively engaged in orchestrating a timely and efficient interface between ARM and the GCM community who use or could use ARM data and facilities; outreaching to scientific groups and federal agencies to offer the services of the ARM user facility; and attending and giving presentations at various national and international fora in order to represent ARM officially, to discover information which would help ARM, and to publicize ARM accomplishments. Internally, the Chief Scientist guides and influences the scientific strategy of the ARM program. This includes: advocating for and helping develop new scientific and instrumental initiatives; advising Department of Energy (DOE) Headquarter managers, the Science Team Executive Committee (STEC), and the Infrastructure Management Board on the scientific and instrumental path forward; organizing the scientific content of the ARM Science Team Meeting (STM); updating the ARM Science Plan as required; developing performance measures to judge progress; spurring the production of one-page ARM research highlights; organizing the Sunset Committee; and serving on the ARM Climate Research Facility Board (ACRF) which reviews ARM field campaign proposals. The Chief Scientist also organizes and sets goals for the four ARM Science Team Working Groups, and attends their meetings. The ARM Chief Scientist’s Office is comprised of the Chief Scientist, four Associate Chief Scientists (two external to Brookhaven National Laboratory (BNL)) who interface with specific projects or Working Groups within the ARM Program, a Postdoctoral Research Associate who works on cloud tomography, and an Administrator. In addition to managerial duties, the ARM Chief Scientist and Associate Chief Scientists actively conduct and publish ARM-related research.

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Statistical Approaches to Aerosol Dynamics for Climate Simulation
2010-BNL-EE619EECA-Budg [KJ0101030]
P.I.: Robert L. McGraw

The quadrature method of moments (QMOM), developed in recent years in collaborations between Brookhaven National Laboratory (BNL) scientists and The State University of New York at Stony Brook (SUNY-SB) mathematicians, provides a statistically-based alternative to modal and sectional methods for aerosol simulation. Key moments of the aerosol population, including number, mass, and mixed moments variances and co-variances, are tracked in place of the distribution itself. The new approach is highly efficient, yet provides the comprehensive representation of natural and anthropogenic aerosols, and of their mixing states and direct and indirect effects, that the Community Climate System Model (CCSM) will require. This Science Application Partnership (SAP) with SUNY-SB uses advanced statistical methods for efficient classification of aerosol physical and optical properties and aerosol dynamics, including the evolution of general aerosol-mixing states. Results will guide development of a new QMOM aerosol module suitable for use in climate simulation. For this purpose, BNL will leverage findings from its current science programs related to aerosols (Department of Energy-Atmospheric Science Program [DOE-ASP]), aerosol-cloud interaction (DOE Atmospheric Radiation Measurement [ARM]), and climate simulation (National Aeronautics and Space Administration-Goddard Institute for Space Studies) to the maximum extent possible to meet Climate Change Prediction Program objectives in collaboration with the inter-laboratory science team.

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