in the News
C. K. Chou
Finding the Missing Piece
in the Climate Change Puzzle
An Elusive TransformationThe
Mystery of Oscillating Neutrinos
Toward a Common Data Model
the VortexNew Insights into the Behavior of Dynamic Fluids
C. K. Chou
Associate Director for Energy and Environment
the Global Climate Puzzle
LAWRENCE Livermore has long been among the leaders in using the most
powerful computers available to simulate the global changes in climate.
As described in the article entitled Finding
the Missing Piece in the Global Climate Puzzle, a key factor in
global climate change is aerosols, which are microscopic particles
suspended in the clear sky and in clouds. Increasingly, scientists
are studying aerosols to help explain our complex climate patterns.
The most recent Livermore simulations show that rising concentrations
of aerosols in the atmosphere may be cooling the planet and thus partially
counteracting the effects from the steady accumulation of greenhouse
The Laboratorys first
aerosol simulations date back to the late 1980s, when researchers
conducted studies of so-called nuclear winter. These studies simulated
the climatic effects of large injections of smoke particles high into
the atmosphere, which would likely follow a large-scale nuclear war.
Every day, different aerosols
enter the atmosphere through natural processes, including dust storms
and sea salt spray. Many other kinds, however, are produced by human
activities such as the burning of fossil fuels and biomass. Understanding
the geographic distribution of aerosols produced by human activities
and their distribution within the atmosphere by particle size is crucial
to understanding climate change.
Department of Energy is interested in aerosols because of their effects
on climate. Their influence on clouds is especially significant, which
is why cloudaerosol interplay is an important aspect of DOE-sponsored
climate change research.
DOE also sponsors aerosol research
because regulators must keep aerosols in mind when formulating energy
policy. For example, regulators have placed restrictions on diesel
emissions because they produce aerosols that, in high concentrations,
can be harmful to people. In this respect, aerosols are important
to air quality and human health. Aerosols composed of small particles,
such as soot and sulfur dioxide, can lodge deep within our lungs and
cause respiratory ailments.
Some forms of aerosols may
also be involved in the carbon cycle and the ocean's ability to absorb
carbon. The carbon cycle is the flow of carbon compounds between the
biosphere, atmosphere, and oceans. When dust aerosols containing iron,
for example, are deposited in the ocean, this iron can help accelerate
natural oceanic processes that take up carbon from the atmosphere.
An important mission of the
Energy and Environment Directorate is studying the link between energy
production (and the fuels used in this production) and the resulting
environmental consequences. Aerosols play an important role linking
such diverse processes as energy production, air quality, atmospheric
chemistry, climate change, human health, and possibly, the carbon
Simulating these processes,
many of which are incompletely understood, and validating the simulation
results require enormous amounts of data and the most powerful supercomputers.
The Laboratory has long excelled in using supercomputers for understanding
complex physical systems. Livermores Energy and Environment
Directorate is applying its modeling expertise and Lawrence Livermores
computing platforms to further understanding of aerosols and their
relationship to energy, the environment, and human health.
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April 16, 2003