Oceanography | September 2020
Oceanography
THE OFFICIAL MAGAZINE OF THE OCEANOGRAPHY SOCIETY
VOL.33, NO.3, SEPTEMBER 2020
Life in Internal Waves
A Review of
Secchi’s Contribution
to Marine Optics
Advancing Ocean
Observation with
an AI-Driven Mobile
Robotic Explorer
The Story of
Plastic Pollution:
From the Distant
Gyres to the Global
Policy State
Oceanography | Vol.33, No.3
Oceanography | September 2020
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contents
VOL. 33, NO. 3, SEPTEMBER 2020
REGULAR ISSUE FEATURES
26
A Review of Secchi’s Contribution to Marine Optics and the Foundation
of Secchi Disk Science
By J. Pitarch
38
Life in Internal Waves
By J.C. Garwood, R.C. Musgrave, and A.J. Lucas
BREAKING WAVES
50
Advancing Ocean Observation with an AI-Driven Mobile Robotic Explorer
By A. Saad, A. Stahl, A. Våge, E. Davies, T. Nordam, N. Aberle, M. Ludvigsen, G. Johnsen,
J. Sousa, and K. Rajan
ROGER REVELLE COMMEMORATIVE LECTURE
60
The Story of Plastic Pollution: From the Distant Ocean Gyres to the
Global Policy Stage
By C.M. Rochman
DEPARTMENTS
03
QUARTERDECK. Reflections
By E.S. Kappel
04
FROM THE PRESIDENT. Ocean Sciences During the Fall Season:
The End and the Beginning
By M. Visbeck
05
RIPPLE MARKS. Turn Off the Lights: Artificial Light at Night, a New Threat to
Beleaguered Coral Reefs
By C.L. Dybas
08
COMMENTARY. Equity and Safety in Polar Oceanography? Let’s Start with
Equal Chances of Survival. Literally.
By A. Glüder
10
COMMENTARY. Maury for Modern Times: Navigating a Racist Legacy in
Ocean Science
By P.K. Hardy and H.M. Rozwadowski
16
COMMENTARY. Integrating Oceanographic Research into High School
Curricula: Achieving Broader Impacts Through Systems Education
Experiences Modules
By M.V. Orellana, C. Ludwig, A.W. Thompson, and N.S. Baliga
21
COMMENTARY. Lessons Learned from Running a Conference in the Time of
COVID-19 and the Silver Linings of Shifting to Online
By H.E. Power, M.S.S. Broadfoot, A. Burke, P.M. Donaldson, R.M. Hart, K.C. Mollison,
D.J. Schmidt, and S.M. Young
71
HANDS-ON OCEANOGRAPHY. Sound and the Seafloor: Determining
Bathymetry Using Student-Built Acoustic Sensors
By R. Levine, S. Seroy, and D. Grünbaum
78
THE OCEANOGRAPHY CLASSROOM. A Viral Shift in Higher Education?
By S. Boxall
50
Oceanography | September 2020
ON THE COVER
Onshore-moving nonlinear internal waves in
the waters off La Jolla, California, concentrate
bands of the motile, bioluminescent dinoflagel-
late Lingulodinium polyedra. For more on how
horizontal drift and vertical swimming in inter-
nal waves modulate plankton's immediate envi-
ronment, see Garwood et al., in this issue. Photo
credit: Eddie Kisfaludy/SciFly
Oceanography | Vol.33, No.3
EDITOR
Ellen S. Kappel
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Services Inc.
ekappel@geo-prose.com
ASSISTANT EDITOR
Vicky Cullen
vcullen@whoi.edu
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Johanna Adams
johanna-adams@cox.net
Oceanography
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Oceanography contains peer-reviewed articles that chronicle all aspects of
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noteworthy achievements, exciting new technology, and articles that address
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nology. The overall goal of Oceanography is cross-disciplinary communica-
tion in the ocean sciences.
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Oceanography | Vol.33, No.3
Oceanography | September 2020
Reflections
Reflections
This September 2020 Oceanography doesn’t have a special issue
section, but if I had to provide a title for the issue, it would be
“Reflections.” Subjects the articles and commentaries ask us to
reflect on include racism and gender bias in the ocean sciences,
the benefits and pitfalls of conducting conferences virtually, les-
sons learned while developing broader impact activities, and the
optical oceanography legacy of Angelo Secchi, among others.
Some of the topics addressed here may take us out of our
comfort zones. Hardy and Rozwadowski reexamine the legacy
of nineteenth-century naval officer and early ocean scientist
Matthew Fontaine Maury. While Maury did not own slaves, his
actions supported the institution of slavery. Our authors pose the
question, what should ocean scientists “do with this new found
awakening to Maury’s dual admirable and reprehensible lega-
cies?” Applying contemporary standards to centuries-old conduct
is a challenging exercise, but we need to take the time to reflect on
how we teach about such historical figures as we simultaneously
develop strategies to increase diversity in the geosciences.
Glüder’s commentary addresses gender bias by examining an
extremely tangible example: why don’t many research vessels have
an adequate supply of survival equipment in smaller sizes suit-
able for women—and also for men who do not fit the “50th per-
centile North American male” physique. The issue here concerns
not only survival in frigid ocean waters but also the feeling of not
belonging caused by the lack of proper safety equipment.
The inclusion of “broader impact” activities is a requirement
for many science proposals submitted to US federal agencies.
Orellana et al. describe how they developed successful high
school ocean science curriculum modules and leveraged several
grants to retain continuity of the project. They also reflect on the
solutions that enabled the success of their broader impacts proj-
ect and share those lessons learned.
Thrust into this COVID world of relative isolation, conferences
have had to test the waters of the virtual world. Power et al. share
their experiences conducting a Young Coastal Scientists and
Engineers Conference online. They reflect on the numerous pos-
itive outcomes of holding a virtual conference, some unexpected,
and note that even when in-person conferences are again possi-
ble, they will likely always incorporate some online component.
The hands-on oceanography activity, “Sound and the Seafloor,”
by Levine et al. introduces students to the concept of acous-
tic reflection (sorry) by having them build their own simplified
echosounders, deploy their instruments to map a transect, and
use the data to explore sampling resolution. The article does have
a section called Reflection (really) in which the authors suggest
questions that can stimulate students to consider the implications
of their observations and the sources of variability.
Pitarch illuminates the optical oceanographic legacy of
Angelo Secchi, the nineteenth century Italian astrophysicist
widely known for the reflective (sorry again) white disk that
bears his name. In this article, Pitarch calls attention to a mostly
ignored 1865 cruise report in which Secchi addresses such ques-
tions as “how the angle of the sun, the disk’s color and direc-
tional reflectance, the disk’s diameter, the ship’s shadow, and
cloudiness influence the transparency measurements.”
In her Revelle Lecture article, Rochman tells the story the his-
tory of research surrounding plastic pollution in the ocean. She
reflects on how a little more than a dozen years ago, the words
plastic and pollution were not yet linked as an environmental
issue, but today plastic pollution has become a global policy
issue with research going in many new directions.
Other articles in this issue describe new and exciting ocean
science and engineering areas and take look at an important
topic of study that has been largely neglected. In their Breaking
Waves article, Saad et al. demonstrate how it is possible to inte-
grate artificial intelligence methods into an autonomous under-
water vehicle to accelerate the analysis of the spatiotemporal dis-
tribution of microorganisms in the ocean. In their Regular Issue
Feature, Garwood et al. use idealized numerical simulations to
show the importance of accounting for horizontal motions in
internal waves when studying coastal ecosystems.
If I may provide a couple of other important reflections from
this September issue: I am particularly pleased and proud to see
the number of graduate students and early career scientists who
are first authors (Garwood, Glüder, Levine, Saad) or coauthors
(in Levine et al., Power et al., Saad et al.) of articles. I am also
very encouraged that women are first authors (Garwood, Glüder,
Hardy, Orellana, Power, Rochman, Saad) on seven of the nine
articles—perhaps a counterbalance to some of the data coming
out that indicates women are publishing less during COVID.
One final reflection. While Oceanography has “grown up”
considerably since it was first published in 1988, this September
issue also displays how we have remained true to our roots.
As the first Oceanography editor David A. Brooks wrote in
the inaugural magazine issue, “the guiding principle and edi-
torial policy of Oceanography Magazine will remain steadfast
and inviolate: we intend to serve, promote, and chronicle all
aspects of ocean science and its applications, and we invite you
to join in the adventure.”
Ellen S. Kappel, Editor
QUARTERDECK
Oceanography | Vol.33, No.3
FROM THE PRESIDENT
Ocean Sciences During the Fall Season:
The End and the Beginning
For those who live in the higher latitudes of the Northern
Hemisphere, the fall season usually marks the end of summer
fieldwork. This year, for some of us, the field season never fully
started or didn’t happen at all, as the coronavirus pandemic
changed the world. Many oceanographers were unable to ven-
ture out to sea, take samples, and observe and record environ-
mental conditions. We could not proudly look back on a new
discovery or an exciting data set that should prove our hypothe-
sis or provide new insights into an ocean process. We could not
deploy a new set of autonomous instruments to collect contin-
uous observations and celebrate its success. In a pre-pandemic
world, we would now be looking forward to working up field
data in our offices and laboratories and repairing and refurbish-
ing instruments. Maybe we would also be catching our breath
and reflecting on the season.
The pandemic has noticeably impacted many other aspects
of our work. During late spring, access to laboratories was sig-
nificantly restricted, and our intricate plans for the summer
field season were falling apart. New plans needed to be made
quickly and were obsolete again a short time later. We needed
to be flexible and were constantly adjusting the way we perform
our science. We felt exhausted before the field season began,
not knowing if, in fact, it even would begin. Instantly, most of
our communications were switched to digital media. There was
no sharing of a coffee, no bumping into a colleague randomly,
no chitchats with students and staff. Hope for a quick return to
“normal” gave way to the realization that the global pandemic
will be with us for many months to come.
Today, we are still weary. The field season was barely produc-
tive. We participate in a seemingly endless stream of online meet-
ings. We are tired of staring at the computer screen and long for
those days in the field and when we could meet in person with
colleagues. Although we move less physically, the rapid switch-
ing from online meeting to online meeting leaves us breathless
and exhausted. We simply need a break from it all.
On the other hand, the fall season also marks a beginning. It
is typically when many expert gatherings happen where we share
our discoveries and discuss and debate our science with col-
leagues. It is also the time to publish and teach. Moreover, it is
a time to begin planning for the next field season and assemble
new teams, establish new partnerships, and sketch out a new proj-
ect or experimental setup. The anticipation of the next summer’s
field season with better sensors or more instruments, a new ship
or platform, or a more promising location keeps us optimistic.
Fall is also a good time to consider our plans for ocean sci-
ences in the coming years and post-pandemic times. As a result
of the pandemic, TOS learned how to run electronic meetings
efficiently. We’ve had more TOS Council meetings than in past
years, with much greater attendance. We miss the social inter-
actions, but our meetings are now shorter, with stringent agen-
das, and the frequent use of electronic voting tools helps to
rapidly come to consensus. There seems little desire to go back
to in-person Council meetings.
What have we accomplished at TOS? We have established
three new awards—TOS Mentoring, TOS Early Career, and
TOS Ocean Observing—and have grown our student member-
ship dramatically. We have also used this year to reflect gener-
ally on the ocean science community engaged in TOS. Have we
succeeded in connecting to and fully embracing new opportu-
nities? As a first step in reaching out further, the TOS Council
established three new Council positions: one to bring in the per-
spective of the early career scientist, one to engage deeper with
the ocean data and informatics community, and one to enhance
connections with the areas of social science, ocean policy, and
ocean governance. We also considered the broad profile of
our TOS membership and the ocean sciences community and
determined that TOS does not fully reflect the diversity of the
greater society. We established a JEDI committee that is charged
with making concrete suggestions to advance issues of justice,
equity, diversity, and inclusion. The committee will support the
TOS community in embracing and celebrating our differences,
broadening participation, and creating a culture of belonging.
Moreover, we are engaging in deep discussions about the future
of our Ocean Sciences Meetings, with the next one scheduled
for 2022 in Hawai‘i. What is the optimal mix of in-person and
remote participation? How will the business model shift? How
can we best support our TOS and ocean sciences communities?
Looking back over 2020, we mourn a partially missed field
season, personal hardships, and significant disruptions. At
The Oceanography Society, we have only partially completed
our TOS 2030 Strategy process. But once the winter season
wanes, we expect that all of us will feel energized and ready for
a new ocean science season. We look forward to deeply engag-
ing with our membership to develop an exciting, innovative,
impactful, and inclusive TOS Strategy 2030 in order to shape the
future of our Society.
Martin Visbeck, TOS President
Oceanography | September 2020
Satellite view of artificial light
at night. Credit: NASA
TURN OFF
THE LIGHTS
Satellite images of Earth at night: bright
dots and shining webs that tell the story of
humans’ seemingly endless sprawl across
the globe.
Artificial “sky glow” can now be detected
along 22% of the world’s shorelines. That
figure is expected to increase dramatically
as human populations along coasts more
than double by 2060.
All that light has a downside. Concerns
have recently bubbled up about the dam-
aging effect of artificial light at night, also
known as ALAN, on humans and other spe-
cies. At the top of the list are coral reefs.
Artificial light at night and how it affects
corals is the subject of new research by
scientists at several institutions, including
the University of Southampton in the UK.
With funding from the UK Natural Envi-
ronment Research Council, Southampton
scientists Jörg Wiedenmann and Cecilia
D’Angelo of the university’s Coral Reef
Laboratory are tackling gaps in our under-
standing of how ALAN affects the repro-
duction of reef corals.
They are working with a team at Bangor
University and other UK research institu-
tions, the Interuniversity Institute for Marine
Sciences in Eilat, Israel, and the Horniman
Museum in London. The research is part of
a larger project led by University of Bangor
scientists studying the impacts of artificial
light at night on marine life.
“ALAN represents an emerging threat
that has received little attention in the
context of coral reefs, despite the poten-
tial of disrupting the chronobiology, phys-
iology, behavior, and other biological
processes of coral reef organisms,” write
Inbal Ayalon and Oren Levy of Bar-Ilan
University and their colleagues in a 2019
paper in Global Change Biology.
Coral reefs are in decline as a result
of climate change, coastal construction,
overfishing, pollution, and nutrient enrich-
ment, says Wiedenmann. “The key to
coral reef survival is for the remaining indi-
viduals to produce enough offspring that
can survive on damaged reefs and help
the reefs recover.”
ALAN, however, presents a major road-
block.
To maximize reproductive success, many
corals release their eggs and sperm at the
same time, sometimes on only a single
night of the year in a process called mass
coral spawning. The timing of spawning is
thought to be synchronized with and trig-
gered by the light of the moon. Scientists
fear that increasing levels of artificial light
at night may override age-old signals from
moonlight, resulting in less efficient coral
reproduction and reduced recruitment of
juvenile corals.
Coastlines are exposed to artificial light
at night near piers, promenades, ports,
harbors, and dockyards. They’re increas-
ingly illuminated with LED lighting, which
penetrates deeper into seawater than
older lighting technologies. LED lighting is
predicted to make up 69% of global light-
ing by the end of this year, exacerbating
ALAN’s effects.
The presence of artificial light in coastal
regions has the potential to interfere with
natural light cycles, ultimately reshap-
ing the ecology of coastal habitats, says
Wiedenmann. “We know that many
marine invertebrates are extremely sen-
sitive to natural light throughout their life
cycles, and that gradients of light intensity
and color, largely caused by variations in
moonlight and sunlight, are major factors
in marine ecosystems.”
Artificial Light at Night, a New
Threat to Beleaguered Coral Reefs
By Cheryl Lyn Dybas
Oceanography | September 2020
RIPPLE MARKS: THE STORY BEHIND THE STORY
Oceanography | Vol.33, No.3
Coral spawning is a spectacularly synchronized event. The larg-
est coral mass spawning event in the world takes place on the
Great Barrier Reef off the coast of Australia. Credit: Oren Levy
He and colleagues believe scientists
need to find out how much damage is
caused by artificial light at night and quan-
tify the benefits of less intense forms of
artificial light on corals and other sensitive
marine species. That information, accord-
ing to Wiedenmann, is vital to the future
of coastal habitats, especially coral reefs,
around the world.
LIGHT POLLUTION: A THREAT
TO GREAT BARRIER REEF AND
RED SEA CORALS
In a discovery that scientists believe will
help guide reef ecosystem protection
plans, researchers in Australia and Israel
have pinpointed artificial light at night as
a threat to coral reproduction on the Great
Barrier Reef.
Work at the University of Queensland’s
Heron Island Research Station confirms
that the Great Barrier Reef’s annual coral
spawning is dependent on an intricate mix
of conditions, with moonlight playing a
vital role. The introduction of artificial light
at night competes with moonlight and can
prevent corals from spawning, the univer-
sity’s Paulina Kaniewska, Oren Levy of Bar-
Ilan University, and their colleagues found.
The research is providing insights into
how corals have fine-tuned and coordi-
nated the release of eggs and sperm into
the water for fertilization. The results are
published in the journal eLifeSciences.
Corals have a “spread-out” nervous sys-
tem that allows them to transmit signals on
a cellular level in response to changes in
light conditions, according to Kaniewska
and coauthors. Their study suggests that
these cellular processes are triggered by
a protein similar to photosensitive melan-
opsin, one of a family of light-sensitive ret-
ina proteins, called opsins, in vertebrate
eyes. In mammals, melanopsin plays an
important role in synchronizing circadian
rhythms with the daily light-dark cycle.
The research is resolving long- standing
questions about how corals synchronize
the mass release of their reproductive
cells with the phases of the moon and
other rhythms. The effects of light on the
timing of spawning are important because
reproduction is vital to reef survival, the
scientists say. They believe that light pollu-
tion is a major threat to coral reproduction.
Coral spawning on the Great Barrier
Reef is a spectacularly synchronized
event. Changes in water temperature,
tides, sunrise and sunset, and the intensity
of moonlight trigger an annual large-scale
mass spawning of coral species.
To maximize their chances of success,
more than 130 Great Barrier Reef coral
species spawn during a time window that
is 30–60 minutes long. It’s the largest
coral mass spawning event in the world.
Most corals are “broadcast spawners”
that simultaneously release their eggs and
sperm into seawater. The egg and sperm
cells combine and develop into larvae that
settle back onto the reef to form new coral
colonies. Coral species spawn at the same
time to improve their chances of success-
ful reproduction.
How corals time this spawning behav-
ior with moon phases was an unanswered
question for decades. Then, Kaniewska
and
colleagues
exposed
Acropora
millepora— one of the dominant coral
species on the Great Barrier Reef—to
different light treatments and sampled
the corals before, during, and after their
spawning periods.
The results show that light causes
changes to gene expression and sig-
naling processes inside the corals’ cells.
The changes drive the release of egg and
sperm cells and happen only on the nights
of spawning.
Next, the researchers exposed Acropora
millepora to light conditions that mimic
artificial light at night. A mismatch in cel-
lular signaling processes prevented the
corals from spawning.
The findings also suggest that the
effects of light pollution can occur fairly
rapidly. Biologists believed that corals took
months to become tuned to the moon-
light rhythms that guide reproduction. But,
it turns out, disruption can occur within
seven days of corals’ exposure to changes
in nocturnal light.
In another study, Levy’s team recently
looked at two coral species, Acropora
eurystoma and Pocillopora damicornis,
in the Gulf of Eilat/Aqaba in the Red Sea.
“The region is undergoing urban develop-
ment that has led to severe light pollution
at night,” Levy says.
The research revealed that corals
exposed to ALAN photosynthesize less.
“Testing different lights such as blue LEDs
and white LEDs showed more extreme
impacts in comparison to yellow LEDs,”
Oceanography | September 2020
state the biologists in Global Change
Biology. The work lends yet more cre-
dence to the emerging threat of light pol-
lution and its impacts on the biology of
corals, says Levy, “and will help in find-
ing ways of mitigating potentially harmful
effects. Reducing the exposure of corals
to artificial light at night could help protect
and regenerate coral reefs.”
CORAL REEF CLOWNFISH
THREATENED BY ARTIFICIAL
LIGHT AT NIGHT
The light-hearted movie Finding Nemo
could soon have a much darker sequel.
Artificial light at night in coral reefs leaves
the famous reef clownfish unable to pro-
duce offspring.
Studies by scientists at Australia’s
Flinders University and the University
of
Melbourne
published
in
Biology
Letters show that an increasing amount
of artificial light at night in coral reefs,
even at relatively low levels, masks nat-
ural cues that trigger clownfish eggs to
hatch after dusk.
Lead author Emily Fobert of the
University of Melbourne says that eggs
incubated in the presence of artificial light
had a zero hatching success rate.
“The overwhelming finding is that arti-
ficial light pollution can have a devastat-
ing effect on the reproductive success of
coral reef fish,” says Fobert. “When ALAN
was present, no eggs hatched but when
the light was removed during the recov-
ery period, eggs from the ALAN exposure
hatched normally. The presence of light is
clearly interfering with an environmental
cue that initiates hatching in clownfish.”
Fobert monitored 10 breeding pairs of
clownfish exposed to an overhead LED
that imitated commercially available and
widely used lights.
The results indicate that increasing
amounts of light at night can significantly
reduce reproduction in reef fish. “These
findings likely extend to other reef fish as
many share similar reproductive behav-
iors, including the timing of hatching
during early evening,” says Fobert.
Some tropical tourist hotspots include
floating accommodations above coral
reefs. Many overwater bungalows have
glass floors with lights shining directly
onto reefs below so guests can watch
fish at night.
Coauthor Stephen Swearer of the Uni-
versity of Melbourne says that clownfish,
along with many other fish species that lay
eggs on coral reefs, are at particular risk
because their larvae usually hatch a few
hours after dusk. “The presence of ALAN
could compromise their natural spawning
rhythms,” he says.
Karen Burke da Silva of Flinders
University, also a coauthor, believes
that an improved understanding of the
impacts of ALAN on coral reefs can lead
to solutions for these stressed ecosys-
tems. “Artificial light at night is becoming
a greater concern among ecologists. Light
is increasing globally and the impacts on
organisms can be severe, but very little
research has been done on ALAN in the
marine environment.”
If we don’t find ways of decreasing artifi-
cial light at night, “Nemo” and his kin may
be among the last clownfish on the reef.
Whither go the clownfish, the rest of the
coral ecosystem may soon follow.
It’s high time, researchers say, to turn off
the lights.
ABOUT THE AUTHOR
Cheryl Lyn Dybas (cheryl.lyn.dybas@gmail.com), a
Fellow of the International League of Conservation
Writers, is a contributing writer for Oceanography
and a marine ecologist. She also writes about sci-
ence and the environment for National Geographic,
BioScience, National Wildlife, Ocean Geographic,
Canadian Geographic, and many other publications.
Researchers are studying the effect of artificial light at
night on reef clownfish reproduction. Credit: University
of Melbourne/Flinders University
Oceanography | September 2020
Oceanography | Vol.33, No.3
COMMENTARY
Equity and Safety in Polar Oceanography?
Let’s Start with Equal Chances of Survival. Literally.
By Anna Glüder
As seagoing Earth scientists, we are used
to taking safety procedures, safety train-
ing, and safety equipment very seriously.
Understandably so: working on ships in
remote regions means that accidents have
the potential to be life-threatening. As a
result, the precautions taken to minimize
the risks of hazards are intended to be
detailed and comprehensive.
Here, I highlight an opportunity for
leadership to extend this strong advocacy
for safety during field operations to an
area that has historically been neglected:
consideration of body sizes other than the
“standard male” when equipping research
ships with survival equipment.
Immersion suits, flight suits, life jack-
ets, and foul weather gear are commonly
stocked as one-size-fits-all. For me, a
160 cm (5 ft, 3 in) tall woman, practice
putting on an immersion suit aboard a
ship usually triggers well- intentioned
jokes about how it could fit several peo-
ple my size rather than questioning
whether in case of a true emergency I
would be adequately protected. In the
words of a mate of a major research ship
who recently provided training on how
to don the immersion suits: “We have
the standard suits, and then some larger
ones and a few extra-large ones. If you are
small, sorry, they are probably not going
to work that well.”
They are not going to work that well. In
Arctic waters, your survival chance with-
out any protection is less than 15 min-
utes. Immersion suits are rated to prolong
that time span to up to six hours, given
a water-tight seal around wrists and neck
and an ideal trim (good fit) after most of
the air is purged from the suit.
The University-National Oceanographic
Laboratory System (UNOLS) safety stan-
dards state that “immersion suits are
required for vessels operating north of
32 degrees north and south of 32 degrees
south and should be type approved under
series 46 CFR 160.171” (UNOLS, 2015,
p. 17-2). The US Code of Federal Regu-
lations (CFR), 46 CFR 160.171-17 speci-
fies that in order to be approved, general
testing has to be conducted on three
females and seven males of three physical
body types. Required tests include don-
ning time, field of vision, walking, climb-
ing, righting, and water and air penetra-
tion. Testing related to thermal protection
is listed separately and specifically calls for
male test subjects to be used. Why has this
testing not been updated to account for
women’s body types?
The International Convention for the
Safety of Life at Sea (SOLAS) adopts reg-
ulations following resolution Msc.81(7),
which are slightly different and require
at least one of six test persons to be a
woman (IMO, 1998). However, in order
to test thermal protections, manikins can
be used that represent the 50th percentile
North American male.
For both UNOLS and SOLAS, the
required thermal protection states that
the wearer’s body temperature may not
drop by more than two degrees when
immersed for six hours in water between
0° and 2°C. The studies on which these
and other legal requirements are based
were conducted on—yes—male vol-
unteers or manikins representing the
50th percentile North American male
(Tipton, 1995; Lewandowski and Clark,
2016). These immersion suit tests con-
trast with the initial studies determining
the rate of heat loss in Arctic waters with-
out any protection, which featured both
males and females (Hayward et al., 1975;
Hayward, 1984).
Not only are the requirements for sur-
vival suits vague, current studies appear
to have skipped even considering what
equipment would be safe for anyone other
than the 50th percentile male. Perhaps this
oversight led to blog posts such as this
one, written from D/V JOIDES Resolution
where immersion suits are supplied in
four different sizes, including a small
one: “There are four basic sizes—small,
medium, large and extra-large. Those
of us on the smaller end of small, how-
ever, are doomed to surviving without
seeing— the zipper comes up level with
our foreheads” (https://joidesresolution.
org/survival-suit-101/).
A suit that is too large will fail in mul-
tiple ways. The most critical function
of immersion protective clothing is to
keep the clothing worn beneath them
dry. Tipton (1995) shows that the criti-
cal limit of cold-water intrusion before
a significant reduction of survival time
is 200 ml (i.e., not quite a cup). It’s easy
to see that an ill-fitting seal at neck and
wrists can be deadly.
A second path to failure is the addition
of buoyancy in the attached boot space.
Most immersion suits are outfitted with
an internal life jacket designed to keep
the head above water to prevent drown-
ing. To work properly, as much air as pos-
sible must be expelled from inside the suit
when donning. The more space there is,
the more difficult it is to push out all the
extra air, which in a worst-case scenario,