Oceans and the Global Environment:
Summary
Oceans and the Global Environment:
taking physics and chemistry outdoors
Peter Rhines1 Eric Lindahl2
Bob Koon2, Julie Wright3
Discovery Seminar 25 Aug-18 Sept 2008
University of Washington
www.ocean.washington.edu/courses/has221a-08
1Prof.
of Oceanography and Atmospheric
Sciences; UW Honors Program
2GFD Lab, School of Oceanography
3M.S. in Biological Oceanography, UW
Lecture 1
course goals
learn about the oceans of Earth, and their importance to plants, animals
including humans
improve our relationship with the natural world…’Nature’
experiment
calculate
build ‘tools’ for your future (whether as a scientist or just a person)
consider ‘deep’ environmentalism…the growing understanding of
interdependence within Nature, which has roots in philosphy and art
as well as science, and implications to medicine, business, law,
international relations, global povery as well as to human-centered
technologies.
1. keep a journal daily (In two forms: in a roughly 8 ½ x 11” bound
notebook…UW Bookstore and as a Googe Document shared with the
instructors online)
class lecture notes
lab experiment notes and results; sketches (diagrams), graphs,
explanations
problem solving notes and results
reading: most interesting ideas; least interesting content
short essays which will be assigned; start your essay the day it is
assigned and let it ‘grow’ in your notebook. When it begins to
look complete put it into your Google document; label it as a
draft until you are happy with it (some of these will be quickturnaround, due the next day). (~typically 2 to 3 page essays)
As an aid to journal-keeping we will suggest some questions about the
reading, lectures and in-class science problems which you can discuss
in your journal.
Lec 1 the layered world
the Gulf Stream this morning…seen by NOAA infrared satellite sensors.
We average for a week to get rid of clouds
http://fermi.jhuapl.edu/avhrr/gs/


104.50 angle formed by
hydrogen- oxygenhydrogen tetrahedon;
covalent bond within the
water molecule yet
‘hydrogen bond’
between molecules
Let’s remove Greenland’s ice (only temporarily)
Topography of the sea floor, constructed from satellite radar altimetry and direct
acoustic ‘soundings’ from ships (Smith & Sandwell)
from Seagar, Introduction to Ocean Science, 2007
dissolved oxygen (in micro mols per kg of seawater), 1500W (purple =
large, yellow=small)
the northern Atlantic Ocean…with its seafloor
topography and the ice-mountain of Greenland
(note vertical exaggeration of the picture! Greenland
is about 3 km tall and 2000 km long…it lies between
600 N and 830 N, which is ¼ of the way from North
Pole to Equator
image:AGU 2003
Erika Dan temperature section from Labrador to Greenland to Ireland, 60N
(red= warm, blue = cold)
surface
4 km deep
Worthington and Wright, 1962
buoyant continents float like icebergs on top of denser mantle

question 1.1: how different is it to swim in Hawaii and to swim in Kansas?

question 1.2: Archimedes, according to legend, determined the king’s crown
was gold, by knowing the density of gold. However the crown had a very
elaborate shape, so he did not know its volume. “Aha” he said and fetched a
basin of water. How did he use the water to learn the density of the metal in
the crown?

question 1.3: how many barbers are there in New York city
Lec 2 the gyre circulations (great
and small)
And.. the result is this circulation of the upper few hundred meters of the oceans, more or less in the
direction of the winds: ‘gyres’ that look like the wind yet are concentrated on the western sides of the
oceans in currents like the Gulf Stream and Kuroshio (‘Black Current’) off Japan. This is the
pressure field (simply related to the average height of the sea surface, by the hydrostatic pressure rule).
Think of these as flow lines, with the currents forming clockwise
gyres in the northern subtropics, and anti-clockwise gyres at high northern latitude. The sense reverses
in the southern hemisphere, since the Earth’s rotation takes the opposite sense ‘down-under’.
Because the flow between to adjacent flow lines involves the same volume of fluid flow, the
speed of the currents is greater where the lines bunch together. The Gulf Stream and Kuroshio
are ‘boundary currents’, very rapid (~ 2 to 4 knots…nautical miles per hour) as a result
the Southern Ocean connects the Atlantic, Pacific and Indian oceans, and
the Antarctic Circumpolar Current circles round Antarctica in response to
the very strong westerly (‘eastward’) winds
Since 1992 it has been possible to see this circulation from space, using radar altimeters on the Topex/Poseidon
and JASON satellites of NASA and the European Space Agency. This a view of the global distribution of sea
surface height. The gyres of circulation are not so clear because this instrument shows only the time-varying part
of the pressure field. NASA is working to determine the background ‘mean circulation’ missing here, using a
remarkable technology of the GRACE satellite mission.
What you do see are thousands of swirling eddies which propagate slowly westward and sometimes originate in
the intensest currents…the Gulf Stream, Kuroshio, and Antarctic Circumpolar Current
figure from Dudley Chelton, Oregon State Univ.
two dynamical ideas: pressure (weight of fluid overhead, per
square meter) and angular momentum…figure skaters

The layers of ocean are not horizontal: so they must be moving.
The forces acting on them are few: gravity and the stress of the
wind overhead. Pressure variations within the ocean act to
redistribute these external forces (like people elbowing one
another in a crowd). So, how would you expect the pressure and
velocity of the ocean to be related?
atmosphere
?
ocean
lower pressure
higher pressure
The peculiar laws of Newtonian physics, when applied to a rotating planet, say that a body tends
to move perpendicular to the force exerted on it….not exactly but largely so. Here we have a
ring of air (or water) centered on the North Pole. A northward force moves it toward the Pole.
The angular momentum, H, of the ring is conserved: the product of distance from the rotation
axis, and total east-west velocity. ‘Total velocity’ means the sum of the wind speed relative to
the Earth, call it u, plus the Earth’s eastward velocity, Ωr.
So H = ru + Ωr2 does not change, as r changes: as r decreases,
u increases, corresponding to an acceleration of the eastward winds. This can be called
the ‘figure-skater effect.’
The Earth spins at a rate Ω
meaning that the length of the day is
2π/Ω. So Ω = 2 π/24 hours
or 7.27 x 10-5 sec-1
Ω is called the angular
velocity
The Greenland waters reaching out over the Labrador Sea also carry strong primary productivity with
them…as seen in SeaWIFS ocean color (May 2004). We have been working in this region with robotic
Seagliders, and have identified the physical circulation that enables the dominant plankton bloom of spring,
seen here from the SeaWiFS satellite (again, yellow to red is high biological activity, blues are low activity).
2005 days 91-120
Lec 3 the conveyor belt circulations
Benjamin Thompson (Count Rumford) 1753-1814:
American colonist in Concord (Rumford) New Hampshire; allied himself
with the British as the Revolutionary War approached, escaped to England
and then Germany: yet he later endowed a professorship at Harvard.
http://www.rumford.com/Rumford.html
Convection in fluids:
Convection without Earth’s rotation
When we add Earth’s rotation to this
heat convection, the ‘figure skater effect’
reorganizes the horizontal circulation.
Basically, the ‘conveyor belt circulations’
now drive strong horizontal currents and
lots of spinning, swirling eddies and strong,
concentrated ‘jet streams’
This true both in the atmosphere and ocean
which have remarkable similarities
The ‘weather’ of the ocean (that is, the
100 km wide eddies) coexists with the
global general circulation (the ‘conveyor’) just
as the weather of the atmosphere coexists
with its general circulation (the easterly and
Westerly winds and the atmospheric
conveyor belt circulation which tranports
heat from warm latitudes toward the poles
P
When the Earth’s rotation comes into play, this pattern of convection
currents is deflected at right angles into ‘east-west’ currents. The east-west
flow breaks into complex, swirling eddies which we call ‘weather’.
Still images from the video of convection with Earth’s rotation…simulated in a bowl with an ice-filled cylinder in
the middle. The ‘Arctic’ at the center cools the fluid, but rather than just flowing in a simple convection pattern as
in the previous slides, Earth’s rotation and the figure-skater effect give the flow strong east-west acceleration. We
see round eddies and jet streams snaking around them. These structures do the work of carrying heat from the
warm latitudes to the cold latitudes. There are actually 2 jet streams: fluid sinks at the cold ‘northern’ wall and
moves south. The angular momentum principle says that this fluid will develop a westward flow (turning to its
right).
Conversely, the fluid rising in the warm latitudes flows north to complete the circuit, but is deflected into an
eastward jet stream, very intense. These complex ‘weather’ patterns do the necessary work of the atmospheric ‘heat
engine’, moving heat poleward and converting thermal energy into kinetic energy of motion. The ocean has
similar instabilities and eddies and jet streams, only they are 10 times smaller in width.
Southern hemisphere and northern hemisphere circulations: weather introduces new time-scales into high latitude life. Left is south
polar view, right is north polar view. There are natural cycles over 10 years and longer, as well as global warming related change in
weather patterns, temperature and rainfall. The jet streams are seen at the 300 HPa level (where just a few contours are selected to
highlight the jets). There is a strong symbiosis between the synoptic highs and lows at the surface, the jet, and the smoother, faster
stratospheric polar vortex above. Note the much more zonal nature of the SH flow. One glitch: colors in the NH are SLP while colors
in SH are 850 HPa temperature….sorry for this confusion!
(dynamic height at 1000 Hpa (colors: blue = low pressure cyclones, red=high pressure anticyclones), 300 Hpa, 30 Hpa 1993 (NH), 1996
(SH) winters, 100 days each
southern hemisphere
northern hemisphere
UW-GFD lab hemisphere
Model of the oceanic conveyor belt circulation, driven by sources of deep water
entering in the far north: Caitlin Whelan, summer undergraduate fellow, GFD lab UW
2007
fluid is pumped
into the model
ocean in the far
north, and flows
south along the
western boundaries
of each ocean basin,
then recirculates in
big gyres near the sea
floor. This peculiar
circulation occurs
because of the ‘stiffening’
of the fluid by its planetary angular momentum
vertical walls (simulating continents)
middepth

deeper
smethie CFCs
deepest
~ 3800m
Lec 4

Flux or ‘transport’ defined for a flowing system with a reservoir:
= concentration C x velocity U x area A
F=CAU

e.g. kg phosphate/m3 x m2 x m/sec
= kg phosphate per second
Residence time (for a steadily flowing system)
= mass of system/flux: Tresidence = mass/F
(can be expressed as reservoir volume/Flux of volume)
Lec 5 Water
Lec 5-08
water, ice, snow and their future under
global warming
image: Petermann Glacier, NW
Greenland Konrad Steffen
Peter Rhines
Oceanography and Atmospheric Sciences,
UW Honors Program
University of WashingtonUniv of Western Australia, 2x05
liquid water is a sort of ‘super molecule’ in which hydrogen bonds between
molecules are fully 1/3 as strong as the interior bonds of each
molecule….and hence we have life
water evaporates
from the Great
Lakes when cold
north winds blow
over them. It
soon condenses
back into water,
as cloud droplets
which then rain
or snow
out…The lake
water has
become cloud,
and then the
cloud piles up as
deep snow,
downwind of the
lakes. This is
called ‘lake-effect
snow’.
change in rainfall predicted for last 20 yrs of this century…stripes of dry and wet
which are similar to the present dry and wet regions…everything gets more
extreme! Meehl et al. Geophysical Research Letters 2005
the legendary Ogallala aquifer supports much of the agriculture in dry central US
regions..yet is depleting rapidly (1/5 the irrigated land in US, 40% of our cattle drank its water in 1970s)
40 to 100m below surface; water dates from last ice age
thickness 0 – 300m. Decline of 9% between 1950 and 2005 (Wikipedia)
As China moves toward industrialization and a diet with more meat, it
begins to use much more water, grain and other resources. The world
grain harvest, once with a big surplus, seems to be turning into a deficit
state.
xxx gallons of water to raise 1 lb of beef:
xxx = 5000 (environmentalist), or 435
(National Cattlemens Assoc.) www.beef.org
Lec 6 estuaries
http://green.kingcounty.gov/WLR/Waterres/hydrology/GaugeMap.aspx
Segar, 2007
text
lab model of the conveyor belt circulation in
an estuary
open ocean
Parker MacCready, UW
Oceanography
river input
Deep time
showing the
cooling of the
Earth since the
end of the
Creaceous period
(the dinosaur era).
There was little or no
snow or ice on Earth
then. Abruptly, about 2.5
million years ago,
the curve starts
oscillating wildly:
the beginning of the
ice ages
Haug et al
Nature 2006
time
Vogelherd horse carved 32,000 years ago from mammoth tusk. This, along with the cave
paintings in France and Spain, represent the earliest discovered art works of humans. This
was the peak of the last ice age, when glacial ice must have been just north of the site of this
art. Development of human intelligence may have occurred
at times of extreme climate and climate change.
What is our place among the millions of species on Earth…the only
known life of the Universe?
Top predator? Sentinal species? Fellow traveler on Spaceship Earth?
Whaling by the Inupiat natives of Alaska’s north slope (image by Charles Wohlforth,
author of The Whale and the Supercomputer. These bowhead whales weight about 100,000 lbs
and may live in excess of 200 years. This says something about the stability of their
environment.
an historian’s
view: evolutionary
strategies of rats
and sharks:
do we adapt or
remain intoxicated
by cheap energy?
how was the
world before
we arrived? How
quickly will it
repair if we are
gone?
of the 5 major reasons
civilizations succeed or
fail, the environment
is central to 3 and involved
in all 5
destruction of forest catchments,
aquifers and natural rivers, with their
regional economies, commodification of
water are acts of terrorism
can-do: solutions found by working through the profit system,
investing in the environment as one values other capital; biomimicry,
closed cycle industries, with zero net imprint on the biosphere,
service-flow economies… Hawken, Lovins & Lovins, Natural
Capitalism, Rocky Mountain Institute, Colorado www.natcap.org