Download File - COSEE Alaska

1
Caught in the News Net
News Stories about Arctic and Ocean Climate Change
Compiled by Alaska Center for Ocean Science Education Excellence
Previous compilations are archived at http://www.coseelaska.net/seanetarchive
Call for Nominations for the First Alaskan Ocean Leadership Awards
Everyone is invited to make nominations for five awards that have been established to encourage and
give recognition to outstanding achievements related to ocean sciences, education and management.
The first annual awards will be announced on January 17, 2010, at the Alaska Sea Life Center's Marine
Gala event at Dena'ina Center in Anchorage. All awards include a $1,000 cash award and certificate.
1. Lifetime Achievement Award (sponsored by the Alaska Sea Life Center): Awarded to a person or
institution that has made an exceptional contribution to management of Alaska’s coastal and ocean
resources over a period of at least 25 years. Permanent engraved trophy at the Sea Life Center.
2. Ocean Literacy Award (sponsored by COSEE-Alaska): To a person, team or institution that has made a
breakthrough in promoting ocean literacy in Alaska among a segment of the general population via
formal or informal education, outreach or other communication.
3. Ocean Media Award: To a journalist, writer, film maker or organization that produced an outstanding
film, book, article, radio or television report that was disseminated by public or commercial media and
which made an outstanding contribution to public awareness of Alaska’s oceans.
4. Marine Research Award (sponsored by the Alaska Sea Life Center): To a research contribution by a
scientist, team of scientists or an institution that is acknowledged by peers to have made an original,
breakthrough contribution to any field of scientific knowledge about Alaska’s oceans.
5. Sustainability and Stewardship Award: To an industry initiative that demonstrates the highest
commitment to sustainability of ocean resources
Awards Committee: Arliss Sturgulewski (Chair), Molly McCammon (COSEE), Clarence Pautzke (NPRB),
Jason Brune (RDC), Mike Devlin (Evergreen Films), Ian Dutton (ASLC) with support from Maryellen Oman
(ASLC)
Nominations can be made by downloading a Nomination Form from Award page of the ASLC website
and returning it through email, fax or mail. Contact [email protected] for more details.
New Study Shows Mixed Effects of CO2 on Shell-building 12/4/09
Ocean Acidification: A Risky Shell Game How will climate change affect the shells and skeletons of sea
life? By Kate Madin, Woods Hole Oceanographic Institute Press Release 12/4/09
A new study has yielded surprising findings about how the shells of marine organisms might stand up to
an increasingly acidic ocean in the future. Under very high experimental CO2 conditions, the shells of
clams, oysters, and some snails and urchins partially dissolved. But other species seemed as if they
would not be harmed, and crustaceans, such as lobsters, crabs, and prawns, appeared to increase their
1
2
shell-building (see interactive).
“Marine ecosystems—particularly those based on calcium-carbonate shell-building, such as coral or
oyster reefs—could change with increasing atmospheric CO2 (carbon dioxide),” said Justin Ries, a
marine biogeochemist and lead author of the study, published online Dec. 1, 2009, in the journal
Geology. Sensitive species could lose their protective shells and eventually die out, while other species
that build stronger shells could become dominant in a future ocean that continues to absorb the buildup
of CO2 in the atmosphere caused by industrial emissions, deforestation, and other human activities.
Excess CO2 dissolves into the ocean and is converted to corrosive carbonic acid, a process known as
“ocean acidification.” At the same time, the CO2 also supplies carbon that combines with calcium
already dissolved in seawater to provide the main ingredient for shells—calcium carbonate (CaCO3), the
same material found in chalk and limestone.
While a postdoctoral scholar at the Woods Hole Oceanographic Institution (WHOI), Ries worked with
WHOI scientists Anne Cohen and Dan McCorkle. In tanks filled with seawater, they raised 18 species of
marine organisms that build calcium carbonate shells or skeletons. The scientists exposed the tanks to
air containing CO2 at today’s level (400 parts per million, or ppm), at levels that climate models forecast
for 100 years from now (600 ppm) and 200 years from now (900 ppm), and at a level (2,850 ppm) that
should cause the types of calcium carbonate in shells (aragonite and high-magnesium calcite) to dissolve
in seawater.
The test tanks’ miniature atmospheres produced elevated CO2 in the tiny captive oceans, generating
higher acidity. The researchers measured the rate of shell growth for the diverse species ranging from
crabs to algae, from both temperate and tropical waters. They included organisms such as corals and
coralline algae, which form foundations for critical habitats, and organisms that support seafood
industries (clams, oysters, scallops, conchs, urchins, crabs, lobsters, and prawns).
In waters containing more CO2, organisms have more raw material (carbon) to use for shells. But they
can only benefit from the high CO2 if they can convert the carbon to a form they can use to build their
shells and can also protect their shells from dissolving in the more acidic seawater. The scientists found
clear differences among species.
“The wide range of responses among organisms to higher CO2—from extremely positive to extremely
negative—is the truly striking thing here,” Ries said.
Not a universal effect
As expected, in the highest CO2 used, the shells of some species, such as conchs—large, sturdy
Caribbean snails—noticeably deteriorated. The spines of tropical pencil urchins dissolved away to nubs.
And clams, oysters, and scallops built less and less shell as CO2 levels increased.
However, two species of calcifying algae actually did better at 600 ppm (predicted for the year 2100)
than at present-day CO2 levels, but then they fared worse again at even higher CO2 levels. Temperate
(cool-water) sea urchins, unlike their tropical relatives, grew best at 900 ppm, as did a temperate limpet.
Crustaceans provided the biggest surprise. All three species tested—the blue crab, American lobster,
and a large prawn—defied expectations and grew heavier shells as CO2 swelled to higher levels.
2
3
"We were surprised that some organisms didn't behave in the way we expected under elevated CO2,"
said Anne Cohen, second author on the Geology paper. "Some organisms were very sensitive [to CO2
levels], but there were a couple [of species] that didn't respond 'til it was sky-high—about 2,800 parts
per million. We're not expecting to see that [CO2 level] any time soon."
Ries and colleagues found that species with more protective coverings on their shells and skeletons—
crustaceans, the temperate urchins, mussels, and coralline red algae—are less vulnerable to the
acidified seawater than those with less protective shells, such as conchs, hard clams, and tropical
urchins.
All of the test organisms continued to create new shell throughout the experiment, Ries said, but some
suffered a net loss of shell because older, more massive portions of their shells dissolved under the
highest CO2 conditions.
Priming the proton pump
To build shells, organisms extract calcium ions (Ca2+) and carbonate ions (CO32-) from seawater, which
combine into the solid crystals of calcium carbonate (CaCO3) that shells are made of. However,
seawater also contains hydrogen ions (H+), or protons. These tend to bond with negatively charged
carbonate ions, leaving fewer for organisms to build shells. So shell-builders have a task: They have to
eliminate hydrogen ions in the places where they lay down shell.
One theory, proposed and discussed by Cohen and colleague, geochemist Ted McConnaughey, is that
shelled organisms solve the problem by creating small, enclosed, fluid-filled spaces next to their shells.
From these spaces, they forcibly pump out protons, leaving behind calcium and carbonate ions that
combine into the crystals that compose their shells.
In a more acidic ocean with more protons, species with stronger “proton pumps” could have an
advantage. But even these species might pay a price: Like an air-conditioner working harder in hotter
weather, the pumps would require more energy. “This increased energy consumption to build shells
may come at the expense of other critical life processes, such as tissue growth and reproduction,” Ries
said.
Temperate urchins fared better than their tropical relatives in the experiments, and Ries and colleagues
hypothesize an evolutionary explanation. Cold water absorbs more CO2 than warm water, so temperate
seas already contain more CO2 and hydrogen—and therefore less carbonate—than the tropics. Ries
speculates that temperate species may have evolved stronger proton pumps to compensate for the
naturally lower carbonate levels in these waters.
The results, Ries said, suggest that the predicted rise in CO2 over the coming centuries could cause
changes in marine ecosystems—particularly those composed largely of shell-builders, such as tropical
coral reefs. Moreover, even organisms that appear to benefit from the elevated CO2 may suffer from
the decline of less tolerant species upon which they depend for food or habitat.
“These results suggest that different types of marine calcifying organisms will respond in very different
ways to any future ocean acidification caused by increased CO2,” said Ries, now an assistant professor
at the University of North Carolina. "Crabs, lobsters, shrimp, calcifying algae, and limpets could build
more massive skeletons, while tropical corals and urchins, and most snails, oysters, and clams could be
less successful at defending themselves from predators than they are today. However, given the
3
4
complex relationships that exist amongst benthic marine organisms, it is difficult to predict how even
subtle changes in organisms' abilities to calcify will ultimately work their way through these
ecosystems."
What happens to carbon dioxide in the ocean?
Pure water is neither acidic nor alkaline; it has a pH of 7.0. But because seawater contains many
dissolved substances, it is actually slightly alkaline (basic), with a pH near 8.2.
The continuing buildup of carbon dioxide (CO2) in the atmosphere means more CO2 going into the
oceans. Carbon dioxide dissolves in seawater to form carbonic acid (H2CO3). The latter rapidly breaks
down into hydrogen ions (H+) and bicarbonate ions (HCO3-), and the bicarbonate ions further break
down into H+ and CO3-2 ions. More H+ ions makes seawater more acidic, but scientists do not think the
seas will become truly acidic (with a pH less than 7.0), but rather less alkaline.
Marine organisms need carbonate ions (CO32-) to build their shells, but ironically the supply of CO32ions actually decreases as more CO2 dissolves in seawater. This happens because more CO2 means
more hydrogen ions (H+) in seawater. Those additional H+ ions form bicarbonate ions (HCO3-), using up
the supply of carbonate ions (CO32-).
When CO2 in seawater increases to 1,800 parts per million (ppm) in tropical waters (with temperatures
at or above 77°F, or 25°C), the supply of carbonate ions in seawater decreases and a threshold is
reached: Aragonite—the form of calcium carbonate commonly used in shell—spontaneously dissolves
to create more carbonate ions and restore a balance of carbonate and bicarbonate ions in seawater.
Colder waters cannot hold as much dissolved carbonate, so the threshold at which aragonite dissolves in
cold waters occurs when CO2 and pH levels in the oceans are lower than 1,800 ppm. Scientists expect
that the cold, fertile Southern Ocean surrounding Antarctica will be the first ocean to reach this
threshold—by 2070.
“The balance is changing,” said Justin Ries, a former postdoctoral scholar in the Ocean and Climate
Change Institute at WHOI. “The change in pH is already occurring in surface waters, and it’s hard to
reverse.” Because carbon stays in the oceans for a long time, to return CO2 levels to those that existed
before the Industrial Revolution, “we’re going to have to reduce CO2 emissions as soon as possible, and
then wait a few hundred years for the oceans to adjust,” Ries said.
ShoreZone Program Wins 2009 Coastal America Spirit Award
Cook Inlet RCAC press release
Forty-one partners will receive the 2009 Coastal America National Spirit Award for their collaborative
high-tech project to inventory every mile of Alaska’s coast. The partners include industry groups, nongovernmental organizations, tribal entities, local, state and federal agencies, and partners from British
Columbia and Washington State.
Since 2001, the Alaska ShoreZone team has collected aerial photos and video of coastal areas. This
powerful visual database is available to the public at the NOAA Fisheries Service Alaska Region website: .
Users can virtually fly the coast, viewing high definition photos and video to identify sensitive habitats
and other coastal features. ShoreZone photos and video are proving to be a vital resource for volunteer
4
5
oil-spill responders and scientists who manage fisheries. Others are using ShoreZone photos and video
to help plan marine debris cleanup efforts, monitor coastal changes due to climate change, and continue
Exxon Valdez oil spill restoration efforts.
Each year, the Coastal America Spirit Award recognizes exceptional projects that address the nation’s
challenging coastal issues. Coastal America is a partnership of federal agencies dedicated to restoring
and preserving coastal ecosystems and addressing critical environmental problems needing multifaceted solutions.
“The ShoreZone mapping project team is an outstanding example of how we can accomplish more by
working together than we can do alone. Coastal America is proud to publicly recognize the team's
efforts,” said Doug Mutter, Regional Environmental Assistant for the U.S. Department of the Interior and
Co-chair of the Coastal America Alaska Regional Implementation Team.
So far, the ShoreZone program has imaged more than 28,000 miles of coastline in Southeast Alaska, the
northern Gulf of Alaska, Prince William Sound, and Bristol Bay. This imagery is already available to the
public for viewing, and additional sections of Alaska’s coastline will be added in the future.
The Coastal America award ceremony will be held on January 19, 2010 at noon at the Alaska Marine
Science Symposium at the Captain Cook Hotel in Anchorage.
List of award recipients and more info
Sea Ice Melt has Implications for Acidification of Arctic Waters 11/2009
Two scientific journal articles published in November, 2009, related the extent of sea ice melt to
undersaturation of aragonite which is required for shell-building by many plankton and invertebrate
species in Arctic waters. A combination of processes are now working to increase acidification and lower
the concentrations of forms of calcite used for shell-building: 1) increased carbon dioxide in the ocean
from anthropogenic sources, 2) freshening and dilution as ice melts, 3) increased biological activity after
the ice melts which takes up calcite from surface waters and depletes it in subsurface waters as organic
matters decays and produced CO2, and 4) upwellings of low pH waters.
Yamamoto-Kawai et. al. published an article in the November 20th issue of Science concerning their
measurements of undersaturated surface waters in the Canada Basin of the Western Arctic Ocean in
2008 which concluded that this was a direct consequence of the recent extensive melting of sea ice in
that Basin. According to the abstract “the retreat of the ice edge well past the shelf-break has produced
conditions favorable to enhanced upwelling of subsurface, aragonite-undersaturated water onto the
Arctic continental shelf. “
The “take-away” messages from the article were summarized by the Teaching Climate Law blog as:
1. The Southern Ocean is predicted to become undersaturated with respect to aragonite by 2030, and in
the North Pacific by 2100; Arctic surface waters will become undersaturated with aragonite within a
decade. This is attributable to freshening related to sea ice melting and increased carbon uptake related
to sea ice retreat;
2. Aragonite saturation has already decreased in the top 50 meters of the Canada Basin; this is the layer
in which rapid uptake of carbon dioxide occurs and increased freshwater inputs take place; this could
have serious implications for many species of marine organisms, including coccolithophore, foraminfera,
5
6
pteropods, mussels and clams. For example, aragonite shell-forming pteropods are concentrated in the
top 50 meters
3. Populations of both planktonic and benthic calcifying organisms in the Canadian Basin are already
being affected by the rapid transition to undersaturation in the Arctic environment, another “canary in
the coal mine” in terms of climate impacts.
Abstract
Full text available by subscription or pay-per-article
Reference: Yamamoto-Kawai, M., F. A. McLaughlin, E. C. Carmack, S. Nishino, K, Shimada. Aragonite
Undersaturation in the Arctic Ocean: Effects of Ocean Acidification and Sea Ice Melt. Science, November
20, 2009. Vol. 326. no. 5956, pp. 1098 – 1100 DOI: 10.1126/science.117419
In a related article, Bates, Mathis, and Cooper (2009) published the calculated calcium carbonate
mineral saturation states for aragonite and calcite for waters of the Chukchi Sea shelf and Canada Basin
during an oceanographic study conducted from 2002 to 2004. The surface waters were seasonally
undersaturated in areas where the sea ice had melted over the Chukchi Shelf and in patches over the
deeper Canada Basin. They considered the phenomenon to be likely a recent one that resulted from the
uptake of anthropogenic CO2 and subsequent ocean acidification. They also related the seasonal nature
of change in saturation rates to the high productivity that occurred after the ice retreated, which would
have served to increase aragonite and calcite in surface waters while subsurface waters became
undersaturated with respect to aragonite as organic matter decayed and released CO2. The abstract
concluded “The benthic ecosystem of the Chukchi Sea (and other Arctic Ocean shelves) is thus
potentially vulnerable to future ocean acidification and suppression of CaCO3 saturation states.”
Reference: Bates, N.R., J.T. Mathis, and L.W. Cooper. Ocean acidification and biologically induced
seasonality of carbonate mineral saturation states in the western Arctic Ocean. Journal of Geophysical
Research Oceans. Published 11/5/09
Less Multi-year Ice in Beaufort Sea than Expected from Satellite Imagery
11/27/09
Environmental Research Web
University of Manitoba
Arctic sea ice has duped satellites into reporting thick multiyear sea ice where in fact none exists, a new
study by University of Manitoba researcher David Barber has found. In 2008 and 2009 satellite data
showed a growth in Arctic sea ice extension leaving some to reckon global warming was reversing. But
after sailing an ice breaker to the southern Beaufort Sea this past September Dr. Barber and his
colleagues found something unexpected: thin, "rotten" ice can electromagnetically masquerade as thick,
multiyear sea ice. And contrary to what satellites recently suggested, we are actually speeding up the
loss of the remaining, healthy, multiyear sea ice.
The results of the study have now been accepted for publication in the peer reviewed journal
Geophysical Research Letters, of the American Geophysical Union. "These are very significant findings
since the scientists and public all thought that sea ice was recovering since the minimum extent in
2007," says Barber, a professor of Environment and Geography and Canada Research Chair in Arctic
System Science.
6
7
In September 2009 Barber and others went to various points in the southern Beaufort Sea aboard the
research vessel (NGCC)Amundsen. They discovered the multiyear sea icescape was not as ubiquitous as
it appeared in satellite remote sensing data. And much of the multiyear ice, which is integral to
maintaining the ecosystem and its inhabitants, was so heavily decayed theAmundsen easily broke
through floes six to eight meters thick. Indeed, through most of the journey the Amundsen sailed at an
average speed of 24km/h; its open water cruising speed is about 25km/h.
"Ship navigation across the pole is imminent as the type of ice which resides there is no longer a barrier
to ships in the late summer and fall," Barber says.
So why have satellites been fooled? When studying sea ice, satellites shoot microwaves at the icescape
and, among other things, record how they scatter. Each variety of ice was thought to have its own
unique scattering characteristics, which researchers could read to determine where certain species of
ice reside. But Barber and his colleagues discovered that multiyear ice and the "rotten" ice have similar
near-surface temperatures, similar near-surface salinities, and both have similar open water and new
sea ice fractions at the surface. So when satellites try to identify who's who, the microwaves behave
similar enough that cases of mistaken identity abound.
"Our results are consistent with ice age estimates that show the amount of multiyear sea ice in the
northern hemisphere was the lowest on record in 2009 suggesting that multiyear sea ice continues to
diminish rapidly in the Canada Basin even though 2009 aerial extent increased over that of 2007 and
2009," the paper concludes.
"This has significant implications for assessment of the speed of global climate change impacts in the
Arctic and for increased shipping and industrial development in the Arctic," says Barberer.
Dr. Barber talks about his research in a video.
COSEE-Alaska selects news articles based on their relevance, timeliness, and
inclusion of scientific information based on peer-reviewed scientific literature
or made available through government agency or research institution
websites or press releases.
COSEE-Alaska does not review scientific information as to its accuracy.
Alaska
PEOPLE, OCEANS AND
CLIMATE CHANGE
7