Scientific Colloquium
January 24, 2014
RALPH
LORENZ
APPLIED PHYSICS
LABORATORY
"Dune Worlds - How Windblown Sand Shapes Planetary
Landscapes"
Dramatic progress has been
made in recent years in understanding sand dunes, a landform
recognized on Earth, Mars, Titan and Venus (and prominent in
fictional
worlds too). Ever-improving remote sensing data allows us not
only to map the extent and morphology of these beautiful
features, but also assay their composition, and observe
their changes, with dune movements now documented on Mars and
Tatooine as well as Earth. Field data gives new insights into
the nonsteady turbulent processes that move sand. Computer
simulations and laboratory experiments now allow us
to quantitatively relate dune forms to the wind regime that
create them, opening a window into the past climates of other
worlds as well as our own. This talk will summarize recent
developments in aeolian studies, illustrated with a wide range
of field, satellite and kite-borne
imagery. .
About the speaker:
Thomson-Reuters Sciencewatch in 2011 named Ralph Lorenz as one
of the
world's top planetary scientists by impact, ranking him #3 by
publications
and #10 by citations (>2200). He holds 5 NASA Group
Achievement awards. He is lead author of the book 'Dune Worlds:
How Windblown Sand
Shapes Planetary Landscapes' published by Springer in early
2014, as well as several other books including 'Lifting Titan's
Veil','Spinning Flight', and 'Space Systems Failures'.
Lorenz led the Science paper in 2006 which discovered sand dunes
in Cassini radar images of Saturn's moon Titan. He has visited
dunes in the Namib, Arabian and Sahara, as well as US and
Australian deserts. His other current research includes Titan
oceanography, as well as dust devils
and seismic measurements on Mars, and balloon dynamics on Venus.
Lorenz is on the Principal Professional Staff of the Johns
Hopkins
University Applied Physics Laboratory. Prior to joining APL in
2006 he was at the Lunar and Planetary Lab, University of
Arizona.
Lorenz has a B.Eng. in Aerospace Systems Engineering
from the University of Southampton in the UK and a Ph.D. in
Physics in 1994 from the University of Kent at Canterbury.