I am currently working with former post-doc Dr. Hjalmar Hatun of the Faroe Islands, graduate students Caroline Harbitz, Nick Beaird and Jonathan Wai (Aerospace Eng.), visiting grad Helene Langehaug (Univ. of Bergen, Norway) and peripatetic senior visitors Dr. Elin Darelius (Univ. of Bergen), Prof. Yakov Afanasyev (Memorial Univ., St. Johns Newfoundland, Canada), Dr. Ole Anders Nost (Univ. of Tromsoe, Norway), Dr. Sirpa Hakkinen of NASA Goddard Space Flight Center, and colleague Prof. Charlie Eriksen, Seagliders in the subarctic Atlantic Ocean. Eric Lindahl and Bob Koon are our GFD lab engineers and instructors.
We have 'Ocean Climate' initiatives supported by NSF and NASA, and NOAA. Check my 'Output page' for more. The Physical Oceanography Research link and the other Research links on the main page provide more climate information. The October 2000 issue of National Geographic Magazine was a colorful view of what we do. We are particularly interested in the effect of the fresh-water cycle in the cold, high latitudes, on climate.
Separate from this is an NSF funded program of basic studies in geophysical fluid dynamics, centering on our lab. The GFD lab is extremely well-equipped both for research and teaching. In addition we have an 1100 square-foot teaching lab which we use for larger classes.
An interesting spin-off of doing this kind of work is a parallel understanding of other worlds! You will see references from the Geology&Geophysics group and Biological Oceanography Group relating to life on Europa and new life forms in sea-floor hot vents. We physicists also deal in the circulations of the planets and stars...particularly the great gas giants.
Jupiter possesses more mass than all the other planets combined. In a sense it is a failed star. Its cloud bands are jet-like zonal circulations and its Great Red Spot is perhaps the largest storm in the Solar System. Our laboratory simulations (see figure below) provide a model for these phenomena, which has been deeply explored by Dr. Gareth Williams at Princeton. We have a special issue of Journal of the Atmospheric Sciences on the topic of jet streams and jet-like ocean currents, in early 2007.
Vorticity
is a spin-like quantity which is active throughout oceans and atmospheres.
Appearing in the fluid atmosphere and oceans, it is
'inherited' from the rotation of the planets themselves. Below
is a vortex-like fractal, a polar vortex produced in our lab by vorticity
stirring due to Rossby waves, and a vortex sheet roll-up in the Weddell Sea
(240km x 360km, made visible by ice).
Teaching and research are both essential components of graduate student
life at UW. The links to courses here show examples where students fulfill their TA requirement
with a serious involvement in the course (not just grading papers!).
Oceans, atmospheres, climate science take physics or chemistry or biology 'out-of-doors'.
Chaos, singular perturbation theory, fractals, and solitons are all examples in which natural,
environmentmal science provided the root discovery that grew into a major branch of physics or
mathematics. Thus, the intellectual flow is not always from the 'mother sciences' to the
'environmental sciences' but has gone in both directions. Read 'What is Oceanography' on the GFD Lab
web page.
I have worked in active seagoing programs in the Labrador Sea for the past
decade or more, studying climate change and the physics of deep convection.
Icebergs there symbolize the interaction of heat, salt and ice in the general
circulation
(though sea-ice and fresh melt-water from land are more important to the upper
ocean).
Prof. Charlie Eriksen and I have launched Seagliders west of Greenland since
October 2003 to observe ocean climate, deep convection and the flows
communicating between Arctic and Atlantic. We established ties with the
Greenland Institute of Natural Resources in Nuuk (formerly Gothab),
the capital of Greenland. This was our base for glider launches.
(You can see more about Seagliders on my GFD lab website under 'OUTPUTS'.)
We have a new initiative with NASA to use the altimeter satellites TOPEX/Poseidon and JASON to map climate change and circulation in the high latitude oceans. This remarkable instrument uses a laser beam to sense the height of the sea surface over a few kilometers. See a paper in Science magazine on Earth Day 2004 about the slowing of the Atlantic Ocean circulation (Hakkinen & Rhines, Science vol 304, p. 555-559).
We were recently funded by NSF to establish a network of observations between Iceland and Scotland, to observe the dominant elements of the global overturning circulation at these far northern latitudes. Launches of Seagliders from the Faroe Islands and NASA satellite altimetry are key elements, and we have an active ongoing exchange program of faculty and students with the University of Bergen, Norway, relating to this work. The Seagliders are presently patrolling the Iceland-Faroe Ridge, providing the first comprehensive observations of the dense, deep overflow waters that cascade down the slopes into the Atlantic Ocean.
In the area of computer simulation, David Bailey and Wei Cheng have completed post-doctoral projects with climate models, looking at the way the global meridional (north-south, up-down) circulation of the oceans is driven by high-latitude climate change, and the singular role of the Labrador Sea in all of this. Wei Cheng, and recently Dr. Hjalmar Hatun of the Faores, are current postdoctoral fellows in our group, looking at climate change and ocean circulation in the northern Atlantic.
I must mention an intense interest in understanding and teaching the changing global environment. The scientific knowledge and skills gathered in researching oceans, atmospheres and climate prepare one well for this complex matter. In the UW undergraduate Honors program the springtime course Introduction the Energy and Environment: Life Under the Pale Sun uses natural and human-related energy cycles to enter into the challenging and compelling matter of global change (not just climate...everything!). In another undergraduate course taught with the Program on the Environment, Earth, Air, Water: the Human Context we have centered on hands-on laboratory experiments as a way to introduce non-science major undergrads to critical environmental issues. This link is for the 2004 year. This year we taught an 'Early Fall Start' course for 19 entering freshment, Oceans and the global environment: taking physics and chemistry outdoors. Our graduate students participate in teaching activities like these as TA's, regularly.
Ironically we also have discovered a new form of
altimetry for laboratory experiments that simulate ocean and atmosphere
circulations and waves. This uses the water surface on our rotating platform as
if it were a telescope mirror with imperfections (its mean shape is a
paraboloid). (Isaac Newton invented the reflecting telescope in 1672, and at
times telescope makers have used a rotating fluid as a base on which to cast
their parabolic mirrors.) The images below show this 'optical altimetry'
revealing Rossby waves and inertial waves produced by flow over a mountain, in a
1 meter-diameter cylinder of water. This experiment models the high latitude
atmosphere or ocean, with the North Pole at the center, as if you are looking
down from space. The mountain is where the tight spiral pattern appears. The
field visualized is the height variation of the water surface, a few micrometers
in amplitude, which accurately shows the pressure and geostrophic flow lines.
Visit the
Geophysical Fluid Dynamics Laboratory:
manuscripts, lecture abstracts, essays, stills and animations of laboratory experiments, links with other GFD groups