Switchboard, from NRDC › Lisa Suatoni's Blog

Can we keep discussions about ocean acidification honest?

2012-01-12T19:19:18Z

Lisa Suatoni, Senior Scientist, New York

In his article, ‘Taking Fears of Acid Oceans with a Grain of Salt’, Matt Ridley recycles the standard arsenal of invalid climate ‘skeptic’ arguments and tactics, but applies them to ocean acidification, the lesser known global impact from rising atmospheric CO2 concentrations.

The result is an exercise in obfuscation. As a scientist working on these issues for the past five years, I was struck by several gaping holes (and inaccuracies) in his piece – taking liberty to manipulate facts in order to misrepresent them.

For instance, he plays unproductive semantic games, arguing that because ocean pH is not predicted to fall below the ‘neutral point’ of 7.0, the term ‘ocean acidification’ is a misnomer. This ignores the fact that scientists refer to a drop in pH as ‘acidification’, regardless of where you are on the scale. The term is simply used to describe the direction of change.

He also makes the same (tired) mistake as those who confuse ‘weather’ for ‘climate’ when he equates short-term natural variation in pH with that of long-term change in the average pH of the world’s oceans. These are not equivalent. That’s like saying there is a drought because it’s been a dry week, even if rainfall is above average for the year.

Contrary to Ridley’s arguments, scientists can measure and differentiate between these two types of variation—and organisms do not experience short-term and long-term variations in the same manner. That is why the sugar maple in my backyard survived today’s 20 degree F fluctuation in air temperature – but the Connecticut population is unlikely to successfully compete with oaks and survive the predicted 4-6 degree F rise in average regional temperature over the next century.

Ridley goes on to raise irrelevant facts by discussing pH and freshwater as a comparison to ocean acidification – but there is no relationship here. While the natural variation of pH in fresh systems is high, it has no bearing on the oceans, or the survival marine organisms.

Worst of all, Ridley flatly misstates research conclusions when he claims that “laboratory experiments find that more marine creatures thrive than suffer when carbon dioxide lowers the pH level to 7.8.” The opposite is true and you can see for yourself:

Hendriks et al., 2010

Kroeker et al., 2010

Gattuso J.P., et al., 2011.

Ridley is correct in pointing out that not all marine organisms will suffer from an increase in ocean acidity. Some, in fact, will likely thrive (e.g., seagrasses). However, he omits the conclusions from the studies he alludes to. In regions with naturally occurring higher levels of acidity, resulting from volcanic venting of CO2, researchers have found substantial losses in marine biodiversity at the same pH levels that are predicted at the end of this century. Specifically there was a 30% decline in overall species richness in Italy (Hall-Spencer et al., 2008) and a 39% decline in hard coral species richness in the Indo Pacific (Fabricius et al., 2011).

If these naturally more acidic sites portend the future of marine ecosystems, does a 30% loss in species diversity constitute a catastrophe for the world’s oceans? It does for people who have come to rely on the affected organisms for income or food.

There are local economies in the United States – and around the world - that rely disproportionately on species that show vulnerabilities to ocean acidification. For example, New Bedford, Massachusetts, which has ranked highest among U.S. ports for values of seafood landings over the past decade, gets 77% of its total landings revenues from sea scallops ($306 million in 2010) (NOAA, 2011). In laboratory experiments, a close relative, the Atlantic bay scallop demonstrates a drop in larval survivorship and impaired shell development as ocean acidity increases (Talmage and Gobler, 2010). And in the Pacific Northwest, oyster hatcheries are already seeing the impact to larval oysters – leaving owners worried about their livelihoods. This alone is cause for concern.

Taking ocean acidification ‘with a grain of salt’ would be a mistake. At the very least, experts and the U.S. government should identify economically vulnerable ‘hot spots’ and begin to monitor the chemical and biological changes that are occurring off our coasts.

Literature Cited:

Fabricius K. E., Langdon C., Uthicke S., Humphrey C., Noonan S., De’ath G., Okazaki R., Muehllehner N., Glas M. S. & Lough J. M., 2011. Losers and winners in coral reefs acclimatized to elevated carbon dioxide concentrations. Nature Climate change 1:165-169.

Gattuso J.-P., Bijma J., Gehlen M., Riebesell U. & Turley C., 2011. Ocean acidification: knowns, unknowns and perspectives. In: Gattuso J.-P. & Hansson L. (Eds.), Ocean acidification, pp. 291-311. Oxford: Oxford University Press.

Hall-Spencer J. M., Rodolfo-Metalpa R., Martin S., Ransome E., Fine M., Turner S. M., Rowley S. J., Tedesco D. & Buia M.-C., 2008. Volcanic carbon dioxide vents show ecosystem effects of ocean acidification. Nature 454:96-99.

Hendriks IE, Duarte CM, Alvarez M (2010) Vulnerability of marine biodiversity to ocean acidification: A meta-analysis. Estuar Coast Shelf Science 86: 157–164.

Kroeker KJ, Micheli F, Gambi MC, Martz TR (2011) Divergent ecosystem responses within a benthic marine community to ocean acidification. P. Natl. Acad. Sci. USA: doi/10.1073/pnas.1107789108.

NOAA, 2011. Fisheries of the United States: 2010. National Marine Fisheries Service/Office of Science and Technology

Talmage, S. C. and Gobler, C. J. Effects of past, present, and future ocean carbon dioxide concentrations on the growth and survival of larval shellfish. P. Natl. Acad. Sci.

The Evaluation of Deepwater Horizon's Environmental Toll (Challenges of a Novel Oil Spill)

2011-01-11T18:18:22Z

Lisa Suatoni, Senior Scientist, New York

In recent months there’s been a lot of talk about how the spill “wasn’t so bad.” My question to that is…By what, or whose, evaluation?

Right now, what we do know about the spill’s impacts is striking. And just as striking are the unanswered questions and possible repercussions we won’t have any sense of for some time.

So, in order to offer some clarity to both what’s known and unknown, here are some examples of both.

What We Know:

The blowout killed 11 workers at sea; their families will never be the same.
Approximately 170 million gallons of oil was spilled into the Gulf – fifteen times the size of the Exxon-Valdez disaster (note: the total output of oil was estimated to be 205.8 million gallons +/- 10%. However, because some of the oil was siphoned to boats, only approximately 170 million gallons entered and contaminated the environment).
650 miles of coastline were oiled (note: an estimated 126 miles were moderately to heavily oiled).
Oil settled into wetlands and estuaries around the Gulf Coast, some of the most diverse and productive ecosystems anywhere, killing marsh grass, accelerating erosion and damaging the cradle of the Gulf, the place young fish, shrimp and crabs rely on in the earliest part of their lives.
By the government's own reckoning, removal (i.e., burning and skimming) got rid of just 8% of the oil from the BP blowout. That leaves approximately 92% contaminating the environment, where it evaporated, dispersed or dissolved in the water, floated to the surface, smothered coastal wetlands, beaches and estuaries or sank to the bottom of the sea.
87,000 square miles – approximately 35% - of American Gulf waters had to be closed to fishing – putting thousands of watermen out of work.
Arguably a year’s worth of revenue was lost for many people in fisheries and tourism industries (the oil spill overlapped with their main seasons).
Residents along the coast - particularly fishermen who rely on the ocean for their livelihoods - have also suffered severe anxiety and social stress. Experts have observed that the social-fallout from man-made disasters is often more severe and long-lasting than that of natural disasters (for numerous reasons man-made disasters results in more social division).
The oil killed wildlife - birds by the thousands, dolphins and whales, fish and hundreds of endangered sea turtles. And that's just the acute impacts that officials were able to observe.
- Approximately 6000 dead birds were collected in and around the spill this spring and summer with the true death toll likely to be much higher (and yet to be estimated). The cause of death is still being determined for some fraction of these birds.
- Approximately 600 sea turtle carcasses were found, a spike in mortality many times higher than usual. Approximately half of the deaths are believed to be related to the oil spill. 278 loggerhead turtle nests were relocated.
- As many as 100 marine mammals were found dead. The cause of death is still being investigated. However, many more are believed to have gone uncounted as dead marine mammals sink out of sight quickly.

But those numbers are from Chapter 1 of a fable that will unravel for years to come. There will undoubtedly be an enduring toll on the Gulf. And here’s some of what remains to be revealed…

How many vulnerable baby fish, oysters, shrimp and crabs survived the spill?
How much oil is on the bottom of the sea?
What harm has it done to deep sea communities?
How long will it persist?
What's happened to important fish habitat, from seagrass beds and coral to giant floating sargassum islands?
Are toxic elements of the oil getting into the food chain?
How badly has this hurt populations of fish like the bluefin tuna, which are already in danger of extinction?

The Deepwater Horizon blowout was a unique ‘oil spill’ in many ways. The event occurred offshore and in deep water and was responded to with an unprecedented application of chemical dispersants. As a consequence, the ecological toll will differ from that of a near-shore, surface spill, such as the Exxon Valdez. The Gulf Coast was significantly affected (in terms of both social and environmental impacts), though, a lot of the harm was directed to the marine environment. The evaluation of this impact will require innovative research and considerable time.

It will take years to answer the outstanding questions. That's the job of the Natural Resource Damage Assessment Process, overseen by the National Oceanic and Atmospheric Administration, in concert with other federal, state and local agencies. They need the time and resources to do the job right.

From the earliest days of the BP blowout the catastrophe has been compounded by official information that was incomplete, contradictory or just plain wrong. Uninformed or premature comments about impacts only add to the confusion at this point, further undermining public confidence and contributing to the risk that the nation won't learn the essential lessons of this disaster.

It is simply too soon to characterize the extent of damage from this spill. And, we owe it to the Gulf Coast residents to do a complete damage assessment.

Breaking down the science in the government's "oil budget" report on the Gulf

2010-08-12T19:27:01Z

Lisa Suatoni, Senior Scientist, New York

Last week, the federal government released a report on the oil budget of the 2010 Gulf oil spill. After reviewing it closely, there were a few things that stood out about the government’s analysis and the ‘roll-out’.

1. The statement that 75% of the oil has been ‘taken care of by mother nature’ - with the implication that it is no longer in the marine environment - is an overinterpretation of the data (and misleading).

After approximately 100 days, about one half of the oil had been removed from the marine environment by burning, direct recovery, and evaporation (note: that one bin combines evaporation and dissolution making the ‘removed’ oil slightly less than 50%). However, approximately one half of the oil - the ‘dispersed’ and ‘residual’ fractions - may still be in the environment. This is a lot of oil (over 100 million gallons -- equivalent to nine Exxon Valdez spills). Given the lack of information about the rate of biodegredation, it is not clear what fraction of the oil remains in the ocean. It is not justified to assume that the ‘dispersed’ fraction is ‘processed’ or gone. Rates of biodegredation need to be measured in the environment at multiple sites and over time (the rates may be non-linear and change over time).

2. The oil budget in the report was a partial tally of the hydrocarbons released into the marine environment -- it did not include methane. And, the oil budget itself was incomplete and lacking important information.

One-half of the hydrocarbons released into the environment from the well (by weight) were in the form of methane gas. These were not included in the budget, yet have important environmental implications. Like oil, methane can be consumed by microbes that require oxygen; population explosions of these microbes can cause depletions in dissolved oxygen concentrations, which can stress or harm marine organisms.

In addition, a number of environmental ‘compartments’ used to identify the different phases and fates of the oil, such as the oil ‘slick’, oil on the ‘coast’, oil on the ‘seafloor’, and ‘biodegraded’ oil, were left un-estimated (see comparisions to oil-budgets from other spills). Estimations for the volume of oil that passes through these various phases, or compartments, are important to developing a full understanding of impacts. We hope that the government fills-in the rest of this story and continues to study the oil in transit, the various weathering patterns, and the fate of all of the hydrocarbons so that a fair and full assesmment of the impacts is conducted.

Fate of Oil	Ixtoc (> 1 year)1	Exxon Valdez (100 days)2	Deepwater Horizon (≈100 days)3
Burned/recovered	6%	≈5%	25%
Evaporated	50%	≈20%	25% *
Dispersed	-	≈20%+	24%
Bio-chemically degraded	12%	≈20%	?
On the coast	7%	≈30%	?
Seafloor	25%	≈<1%	?
% accounted for	100%	100%	74%

1. Jernelov A. and O. Linden. 1981. Ixtoc. I: A case study of the world's largest oil spill, Ambio 10 299.

2. taken from Fig. 3 in Wolfe, D. et al., 1994 The fate of the oil spilled from the Exxon Valdez. Env. Sci. Technology (28) 13 561.

3. Lubchenco J. et al., 2010 BP Deepwater Horizon Oil Budget: What happened to the oil? http://www.deepwaterhorizonresponse.com/posted/2931/Oil_Budget_description_8_3_FINAL.844091.pdf

* In the Deepwater oil budget report, this category was evaporated and dissolved.

3. The released oil budget represents a ‘snapshot’ of the oil, in a moment in time. It does not directly address where the oil has been, where it is going, and how long it will remain in the system (or, importantly, the ecological impacts throughout).

To fully understand the impacts of the oil one would, ideally, estimate the transit and fate of the oil, for the duration of the contamination. Take, for example, the oil budget outlined by Wolfe and colleagues (1994) following the Exxon Valdez spill. It shows that for the first ten days, the oil was mainly in the form of a slick (identified as “floating” in the figure below), encountering wildlife and impacting primarily bird and mammal populations. Between day ‘10’ and day ‘100’, much of the oil had evaporated, dispersed, or was ‘beached’, thus entering a phase of coastal and open-water exposure. By day 1000, most (≈ 85%) of the oil was removed from the environment. However, 15% lingered in sediments in the coast and seafloor, continuing to contaminate the environment and organisms for the ensuing decades. It’s important to note that a small proportion of the oil is recalcitrant and generally remains in the environment for decades.

Wolfe, D. et al., 1994 The fate of the oil spilled from the Exxon Valdez. Env. Sci. Technology (28) 13 561.

4. On the plus side, a relatively high percentage of the oil - 25% - was kept out of the Gulf or recovered in some fashion (through siphoning, skimming, and burning).

This relatively high ‘recovery rate’ is largely because of the ability to siphon oil from the wellhead (17%) before it got into the water. The small fraction of oil burned or recovered once it hit the water (5% and 3% respectively) is a sober reminder that once the oil is released into the environment, it is very difficult to clean up.

5. The fraction of oil that was sucessfully chemically dispersed was arguably a modest percentage of the total (8%) given the unprecedented use of chemical dispersants.

A bound of uncertainty around this estimated value should be determined and that range of values should be factored into a thorough cost/benefit analysis of whether the extensive use of chemical dispersants was a good idea. Important outstanding questions include, how chemical dispersants affected biodegredation rates, whether chemical dispersion increased the biological uptake of the oil, the potential bioaccumulation of the chemical dispersants, the health impacts of chemical dispersants to oil spill responders.

6. The degree of precision associated with the estimated percentages for the fate of the oil was not addressed well in the report.

Typically oil that is recovered, burned, or skimmed is directly measureable, so estimates are likely to be accurate to within ± 10%. The same is true for estimations of evaporation. However, due to the combined challenges of measuring subsurface oil and natural spatial variability in the ocean, the estimation of the fraction of dispersed is much less precise and only accurate to within factors of two or more (see Dr. Jeffrey Short’s discussion of this). The current estimate of 25% in this fraction should be regarded with significantly less certainty.

7. The oil budget is just that - an oil budget; it does not speak to environmental harm.

Oil budgets are an important exercise, but they are just a first step to determining the ecological harm caused by the oil contamination. In order to truly understand the full scope of the impacts of the spill on the Gulf of Mexico, government and independent scientists need to research what harm the hydrocarbons and associated contaminants (e.g., metals) have done and are doing to organisms and the communities. A long-term coordinated research program is needed with sufficient funds to back it up.

Many questions still unanswered on dispersants following EPA report

2010-08-04T16:03:33Z

Lisa Suatoni, Senior Scientist, New York

This week, the EPA released an additional round of research findings on the dispersant used in the Gulf Oil Spill.

The EPA has conducted acute toxicity testing of eight chemical oil dispersants - including the one used in response to the Gulf oil spill - on two aquatic test species which are found in the Gulf, a small mysid shrimp and a small fish, Menidia (neither are consumed by humans).

The first round of EPA laboratory testing found that the dispersants were less toxic than the southern Louisiana crude itself and that they displayed similar toxicities to one another. The second round of EPA testing found that the dispersant/oil mixtures had similar toxicities to southern Louisiana crude itself and similar toxicities to one another (with the exception of the dispersant brand Nokomis/oil mixture which was more toxic to the shrimp than oil alone).

These results represent another piece to a very complex puzzle.

In a statement to the press about these research results, Dr. Paul Anastas said that ‘while more needs to be done, the picture is becoming clearer’ that dispersants were an ‘important tool in this response.’

Dr. Anastas pointed to four lines of evidence:

the dispersants appeared to be helping keep oil off our shoreline (in other words, in the water)
the dispersants are less toxic than the oil being released
the dispersant/oil mixture has roughly the same toxicity as the oil itself
no traces of dispersant have been found ‘away’ from the well head

But while it may be tempting to conclude that the use of dispersants during this catastrophic oil spill was a good idea, we urge the federal government not to hasten this evaluation and rush to judgment.

The unprecedented and widespread application of dispersants in this oil spill was a grand experiment. Given the scale of this spill, its position offshore, and the severe and long-lasting impacts of oil to salt marsh ecosystems, the rational was clear and defensible.

However, as the most recent National Research Council panel on the topic concluded in 2005, much remains unknown about the efficacy and impacts of chemical dispersants. And as a consequence, careful and thorough study of these factors is imperative.

It would be unwise to draw conclusions about the safety of their use following these two laboratory experiments on toxicity (particularly when the results from phase II are not concordant with previous research on the topic) and field evidence that shows the dispersants were successfully dispersing the oil.

Many important pieces of the puzzle are outstanding:

Where has the oil gone? What proportion has hit land, sunk to the bottom, evaporated, or remains mixed into the water column? This final calculus has not been conducted but is essential to understand the efficacy of the dispersants.

How did the chemical dispersion at 5000 feet depth differ from the physical dispersion at that depth that was happening naturally?

How large an area offshore is impacted?

What ocean organisms and ecosystems encountered the oil? What harm has occurred and may occur long term?

Is the chemically dispersed oil – or the dispersants – getting into the food chain; is there the potential for it to get into the food chain?

What are the public health implications of exposure to dispersants by the response workers?

What are the public health implications for food consumption?

It is clear that the use of chemical dispersants is a tradeoff - but it’s not at all clear that we fully understand the tradeoff we made yet. This question of tradeoffs represents a ‘500 piece’ puzzle and cannot be evaluated with four puzzle pieces.

We need federal scientists from NOAA as well as the EPA get to the bottom of the remaining questions. It’s the follow-through that will make this catastrophe less of a disaster.

Go below the surface of the Gulf Oil disaster with a new interactive illustration

2010-07-16T16:33:00Z

Lisa Suatoni, Senior Scientist, New York

From a previous blog of mine, “The many pathways (and impacts) of the Oil – from the surface to the Seafloor”, Kathryn McGrath (NRDC's Manager of Social Media and Blogging) and illustrator Jason Bishop worked together to produce this fantastic interactive illustration of the various potential impacts of the leaked oil in the Gulf of Mexico.

You can see the interactive here on NRDC.org , and there's a sample below.

Because the volume of oil from this incident is so immense and the input is from the sea floor, biota from the entire water column – from top to bottom - are at risk. In other words, there may be no refuge from the hydrocarbons (oil and methane) in the region of the well. This could prove to be a significant characteristic of this event and one that is not well understood by scientists.

The challenge now, as set out in the Oil Pollution Act of 1990, is to document the fate of the oil, its harm, and the necessary actions for restoration. This should be accomplished through two parallel lines of research, science associated with the Natural Resource Damage Assessment (NRDA) and independent, academic research that is funded through a truly independent entity (e.g., the National Science Foundation).

Watch! A Gulf Thick with Life -- and Oil

2010-06-08T20:47:48Z

Lisa Suatoni, Senior Scientist, New York

Southern Louisiana crude has been flooding into the Gulf of Mexico - uncontrolled - for much of the spring. Where is the oil? What is it harming? What unique habitats and biological diversity is at risk? The Gulf of Mexico is rich with life, and there is much to lose.

To learn more, read my last blog post on the many pathways (and impacts) of the oil - from the surface to the seafloor.

The Many Pathways (and Impacts) of the Oil - from Surface to Seafloor

2010-06-04T17:25:02Z

Lisa Suatoni, Senior Scientist, New York

Historically, oil spill response efforts (and research) have focused on impacts to wildlife and coastal ecosystems. This focus is understandable because the surface destruction is visible, and our reaction visceral.

Also, we’ve learned from previous oil spills that impacts to our shoreline can be devastating to a diversity of animals, for long periods of time. This is especially so for salt marshes, which can act like sponges, soaking up the oil and sequestering it in its toxic form for decades. Long-term contamination of marshes on the Gulf Coast - which comprise 60% of the coastal marshes in the United States - could cause substantial ecological and economic harm, as these wetlands serve as nurseries for commercially important fisheries such as shrimp, oysters, and crab.

Protecting the coast is the rationale behind the heavy use of dispersants in this disaster. Currently, the reigning response strategy is to do everything possible to keep the oil off of coastlines.

But, it’s important to keep in mind that the oil that hits the shoreline is what well-respected marine ecologist Jeremy Jackson calls, the ‘ring around the bathtub.’ This is the oil that we can see. And, in the case of Gulf oil disaster, it is only a fraction of the more than 18 million gallons of oil that have flooded into the Gulf of Mexico. The majority of it remains dissolved or dispersed throughout the Gulf’s waters – largely out of our sight.

May 19 - Thick oil pools in the waters near Pass a Loutre, on Louisiana’s coast. Credit: Office of Gov. Bobby Jindal

So what are the impacts of this offshore contamination? Scientists know surprisingly little about these impacts because they are grossly under-studied.

But we do know that oil is toxic and that it will harm just about everything it encounters before it degrades (via chemical oxidation or microbial degradation). Ultimately, the damage done will depend on how large an area it contaminates, how dense it is, and where it goes.

There are numerous scenarios for each of the oil’s various physical states and pathways:

Floating Oil

Oil slicks at sea cause serious harm to animals that need to spend a portion of their time at the surface to breath, feed or rest. This includes animals like birds, turtles, and mammals that will not, or cannot, avoid oiled water.

When air-breathing species such as whales, turtles, and dolphins come to the surface, they may inhale toxic volatile chemicals, leading to respiratory irritation and absorption of the toxins which can cause organ damage, reproductive failure, or death. If these animals die, they will likely sink offshore and many casualties will remain uncounted.

May 6 - Pod of bottlenose dolphins - Chaneleur Sound, LA. Photo credit: Alex Brandon, AP

Dissolved oil and chemically dispersed oil in the upper water column

In the Gulf spill, natural mixing, and the extensive use of dispersants, caused much of the floating oil to dissolve or be dispersed into the upper layer of water below the surface, where life is concentrated in the ocean.

This is where sunlight penetrates and plants grow. Invertebrates like copepods graze on the plants and small forage fish eat the invertebrates. This chain of life could prove highly susceptible to the chemically dispersed oil. What is not wiped out by acute short-term exposure will be contaminated by toxic hydrocarbons. These toxins will then be transferred up the food chain, with cascading impacts to top predators, such as dolphins, seabirds, and large fish. Past research shows that exposure to hydrocarbons through the food chain can result in reduced survivorship, reproductive failure, and reduced reproductive capacity.

Scientists are especially worried about the eggs and larvae that have just arrived with spring and that float in this layer. Many have no protective covering and are essentially permeable, making them especially sensitive to toxins. Fisheries experts predict significant death rates for these juveniles, attrition that could translate to future reduced catch levels of the adults into which they grow.

Splash of seawater. David Liittschwager / National Geographic Stock

Larval swordfish. David Liittschwager / National Geographic Stock

Of particular concern is the impact to the beleaguered western Atlantic blue fin tuna, which uses the northern Gulf of Mexico as their only breeding grounds.

Dissolved and dispersed oil in deep water

Being a deep water spill, the Gulf disaster is exceptional. For example, the bulk of the oil remains below the surface. The documented miles-long plumes of sub-surface oil could contaminate any organisms that live and travel through the deep and mid-water. This includes hundreds of fish species, invertebrates such as squid, and marine mammals such as the Gulf’s resident sperm whales.

Whale shark up close. Photo credit: shutterfly.

Dispersed oil and oil-sedimentation on the bottom

If these plumes of oil, which are said to be as deep as 3,000 ft, contact the bottom, or collide with the continental shelf, they could smother and contaminate the rich bottom habitat of the Gulf, including fields of sponges, sea fans, and coral reefs. The Gulf of Mexico is home to prolific deep water coral reefs. And, corals are particularly sensitive to chemically dispersed oil.

Oil can also be adsorbed by sediment in the water column causing it to sink and accumulate on the sea floor. Such contamination could cause additional problems for commercial fishing because many fish, such as snapper and grouper, reside in coral reefs on the floor of the Gulf. Even closer to shore is essential habitat for the important recreational fish like red drum, which develop in seagrass beds near the coast for three years before emigrating offshore as adults.

Coral and brittle stars on the floor of the Gulf credit: G.P. Schmahl, Flower Garden Banks National Marine Sanctuary

When will we know the scope of the harm?

Currently, we have been forced to speculate about impacts to the Gulf’s diverse ecosystems. This will need to change. Outstanding questions – such as the toxicity of the chemically dispersed oil – need to be answered.

According to the Oil Pollution Act of 1990, the federal government is responsible for overseeing a natural resource damage assessment (NRDA) of this disaster. To properly assess the damage, the oil needs to be quantified, tracked, and its impacts evaluated. Some of these factors are ephemeral and require immediate observation.

Essential Fish Habitat for Red Drum in the Gulf of Mexico (boundary delineatoins from National Marine Fisheries Service). Matthew McKinzie, NRDC

Given that this disaster has been unfolding for over a month, the necessary data to begin understanding the types and scope of the damage should be available. The lack of available open ocean data is disconcerting. The federal government should provide the Natural Resource Damage Assessment plan for public comments (as it has with BP) and post incoming data on a central website for the public to see – so we know which paths the oil is taking, which wildlife its harming, and the full scope of its impact.

Is anyone tracking the oil? If so, the plan and the data should be made public

2010-05-25T18:54:51Z

Lisa Suatoni, Senior Scientist, New York

The need to track (and assess) the oil

The federal government plays two important roles following an oil spill: (1) providing aid and guidance to the cleanup efforts and (2) conducting a damage assessment to facilitate restoration. To achieve these goals the government needs to know not only the volume of oil entering the environment, but where it goes and what it impacts. These roles are not voluntary; they are mandated by law, under the Oil Pollution Act of 1990.

Given that the Deepwater Horizon blowout is offshore, the principal government office tracking the oil at sea and identifying its fate (air, open ocean water, sea bottom, shore) is the Emergency Response Division at the National Oceanic and Atmospheric Association’s (NOAA) Office of Response and Restoration. The Emergency Response Division uses this information to advise the federal on-scene coordinator and the responsible party (in this case, BP) about where and how to concentrate the response efforts. For example, they have been producing and updating the oil slick trajectory maps over the past month. This job is essentially ‘damage control’.

In addition, the federal government, along with state and tribal ‘trustees’, is responsible for conducting a natural resource damage assessment (NRDA). To properly conduct an assessment the trustees need to know the fate of the oil, its byproducts in the environment, and the subsequent impacts to plants, animals, and habitats. Again, given that the spill originates offshore, NOAA will play a key role in this process by tracking the oil at sea and characterizing its chemical and physical state. This will be done through the Assessment and Restoration Division of the Office of Response and Restoration. (The Department of the Interior, which oversees 33 wildlife refuges and several units of national parks/seashores along the Gulf coast, will also play a critical role in the damage assessment process.) This phase can be viewed as ‘damage assessment’.

The necessary research

The Gulf oil disaster is unique and challenging in a number of ways. It is deep, continuous, and dispersants have been applied extensively with unprecedented techniques. Understanding the behavior and fate of the spilled oil will require a carefully designed, aggressive research effort.

In general, tracking the fate of oil released in deep water is significantly more challenging than surface spills. As a 2002 NRC study (Oil in the Sea III) points out, “[t]he release of oil beneath the surface introduces a number of complications compared to oil released at the surface. From the standpoint of fate … important complications are enhanced by dissolution in the water column and, perhaps, emulsification.”

The formation of very small droplets of oil in deep waters can result in the formation of oil plumes below the surface that can expand and travel great distances in currents, undetected. Following a field study of deep sea spills at the Helland Hansen site in the Norwegian Sea, scientists found that they could only account for the fate of less than 28% of the oil, as much of it did not surface in the vicinity of the release location during the trial.

As a result of these challenges, field monitoring and careful surveillance is of particular importance in deep sea spills. Numerical models used to describe the behavior and predict the fate of the deep sea oil releases, are less developed and reliable than models used to track surface spills. Consequently, field data used to validate the models are critically important. Ultimately, the open ocean assessment effort should employ a suite of techniques, including: aerial surveillance to document slick behavior, sonar to track subsurface plumes, autonomous underwater vehicles to sample chemical and physical characteristics of the water, traditional water sampling to characterize the chemistry and toxicity of the oil, bottom sampling to identify contamination of sediments, and sampling of marine life to assess damages.

Rising concerns about monitoring and assessment

A recent article in the New York Times raised concerns that efforts to track the subsurface oil have been lagging. For example, it is not clear why the Emergency Response Division is releasing oil spill trajectory maps for the surface-oil only, when there are indications that much of the oil resides below the surface of the water.

The federal government has given assurances that the necessary research to track the oil and conduct a full off-shore assessment has commenced. Yet questions remain about how coordinated and comprehensive the undertaking is. We believe that making the at-sea assessment plan, and subsequent data, publicly available would go a long way to reducing the growing concern. There is no clear reason for the current lack of transparency.

The enormous, and potentially unprecedented, challenge facing NOAA’s Office of Response and Restoration should be recognized, particularly having lost one-third of its staff over the past five years. If the apparent data lag in ocean sampling is real, and is a consequence of being forced to prioritize ‘damage control’ over ‘damage assessment,’ (e.g., fewer than a dozen of 1200 the boats out on water are studying the spill) the government should take notice immediately and provide NOAA the necessary resources to conduct its simultaneous responsibilities.

The prolonged nature of this event offers an historic opportunity to study oil response strategies and to develop a better understanding of the impacts of deepwater oil spills. It would be a double tragedy to miss this opportunity.

How much oil is spilling in to the Gulf of Mexico? And, yes, it does matter.

2010-05-20T15:09:15Z

Lisa Suatoni, Senior Scientist, New York

Soon after the explosion of the Deepwater Horizon rig, the coast guard and BP estimated that 42,000 gallons (1000 barrels) were leaking from the well each day into the Gulf of Mexico. Within a week this estimate was revised by the government to 210,000 gallons (5,000 barrels) a day.

This round estimate of 210,000 gallons has stuck – accepted with certainty by the federal government - despite multiple independent estimates that suggest the spill is substantially larger.

Oil Slick Size

Initial estimates were based on oil slick size, following the Bonn Convention method. However, independent estimates – also based on the size of the oil slick – questioned the widely reported value of 210,000 gallons per day.

In a statement to the press, Dr. Robert Howarth of Cornell University pointed out that the government’s figure rested at the lower bound of potential spillage rates using oil-slick size as an estimator. His own estimate ranged from 170,000 gallons to 630,000 gallons (4047 to 15,000 barrels) per day.

Using satellite imagery of the oil slick and thickness estimates from visual descriptions, John Amos of Sky Truth and Dr. Ian MacDonald of Florida State University estimated a minimum average flow rate of 1.1 million gallons (26,500 barrels) per day – five times the original estimate. Differences between their calculations and the governments can not be identified because the government’s computation has not been made public.

In truth, it appears that oil-slick size is not the best estimator given the depth of the spill, the heavy use of dispersants during the response, and the evidence that a substantial amount of oil is remaining below the surface (quite possibly the result of physical dispersion of the hot liquid during entry into the cold, high pressured deep waters), resulting in a likelihood of underestimating the spillage rates.

Other Available Methods

Experts point out that a range of alternative, and more suitable, methodologies exist. They include direct physical measures of velocity with flow meters (this would, admittedly, be challenging), acoustic methods, and visual analysis of particle flow from the leaking pipe (particle image velocimetry).

Immediately following the release of footage of the leak, a number of updated measures were provided by independent scientists. According to an NPR story, Steven Wereley, an associate professor of mechanical engineering at Purdue University, conducted visual analysis of the leaking pipe estimating between 2 and 3.5 million gallons (56,000 barrels to 84,000 barrels) per day. According to NPR other scientists employing similar methods also generated estimates in the millions of gallons (or 10,000s of barrels) per day.

Why the size of the spill matters

BP and the federal government repeatedly argue that measuring the volume of oil entering the Gulf is not a priority, that a more precise measure of flow rate is not important. Their rationale is that it would not influence the response in any way.

We disagree for a number of reasons:

Scale. The flow rate estimates differ by a factor of ten. Differences on this scale are not quibbles; they are big, fundamental differences.
Response. The discrepancy is sufficiently large enough to influence response strategies. For example, to promote the efficacy of dispersants, they are applied at a specific ratio to the volume of oil. This is not possible if the volume is unknown, by this large of a degree. In addition, the ability to successfully cap the well, engineer a dome, or pump the oil to the surface depends on a good estimate of the oil flow rate (both in terms of volume of oil and the force with which it is exiting the pipe).
Law. Under the Oil Pollution Act of 1990, a natural resource damage assessment (NRDA) must be conducted. This entails assessing the input of oil, its fate (i.e., where it goes, what it coats and contaminates), and the damage it caused. The ability to fully conduct this accounting – or ‘mass balance’ - requires knowing the initial volume of oil.
Financial Penalty. Following discharge of oil into a water body, the federal Clean Water Act allows for a civil penalty of up to $1,000 per barrel of oil spilled. This penalty can not be calculated to its fullest extent without knowing the total volume of oil.
Future emergency plans. Knowing the magnitude of this spill is necessary to inform future emergency response plans. Substantial underestimates of the volume of oil leaking from Deepwater Horizon will leave us unprepared in the future.

There are multiple reasons why BP may not want the true amount of oil to be known. Just take for example, the $1000 per barrel of oil spill civil penalty under the Clean Water Act. Using the “official” number of 5,000 barrels per day, their current tally is $140 million (and counting). Using some of the higher estimates provided by visual analysis of the leaking pipe, BP’s current tally is in the billions (and counting).

The bigger mystery is why the federal government is sitting on the sidelines. Why has the federal government been reluctant - and so slow - to undertake its own assessment of the size of the spill, particularly given the available expertise and alternative methods?

Why Scientists Agree Ocean Acidification is Undeniably Caused by Humans

2009-10-16T20:58:18Z

Lisa Suatoni, Senior Scientist, New York

A past comment on this blog raised an excellent question. Captain Crutcher writes:

"How can we be sure that this cycle we are observing with our highly tuned skills is caused solely by humans ... has this happened before, prior to our human ability [to] influence marine ecosystems?"

So, how do scientists know that the observed decrease in average ocean pH - or rising acidity - over the past two hundred years is the direct result of human activities?

The short answer is because theory (i.e., the laws of physics and chemical thermodynamics) predicts it, and observations confirm it.

There are three well established processes in the phenomenon of ocean acidification:

Atmospheric CO2 concentrations are rising, primarily from the combustion of fossil fuels (see 'Keeling curve' below).
The ocean absorbs a large amount of this CO2. It has to. There's no known mechanism that would prevent this.
When CO2 gas dissolves into water, it becomes an acid.

CO2 + H2O ↔ H2CO3 ↔ H+ + HCO3-. (H2CO3 is carbonic acid which immediately dissociates and releases a hydrogen ion, H+, which is the 'acid').

It is important to note that these processes are not complex; they are known to be true and are observable and measurable.

The theoretical underpinnings of chemistry allow scientists to predict the expected change in pH (or 'rise in acidity') in surface waters, given the influx of a known amount CO2 into the ocean. These predictions are verified by what we measure happening in the ocean.

The figure below, showing field measurements of CO2 in the air and the ocean at Hawaii, illustrates this point well. The red diamonds show rising atmospheric CO2 concentrations as a result - primarily - of fossil fuel combustion (this is the famous 'Keeling curve'). The dark blue diamonds show the concomitant rise in CO2 in the ocean. Although more variable (due to local variations in weather, temperature, biology, and mixing) the rise in oceanic CO2, clearly tracks the rise in atmospheric CO2. Finally, the light blue diamonds show ocean pH declining by the expected amount given the measured influx of CO2. Other long-term pH sampling stations around the world (e.g., Bermuda and the Canaries) tell similar stories.

Time series of: (a) atmospheric CO2 at Mauna Loa (in parts per million volume, ppmv) (red ), surface ocean pH (cyan), and pCO2 (μatm) (tan) at Ocean Station ALOHA in the subtropical North Pacific Ocean (From Doney et al., Annual Review of Marine Science, 2009 1: 169-92)

In other words, we see a declining trend in ocean pH, and we can attribute that trend quantitatively to the rise in atmospheric CO2 due to fossil fuels. The concurrence between theory and observation - as well as the absence of good alternative explanations - gives scientists high confidence that carbon dioxide pollution is causing ocean acidification.

It's really not much different from predicting that a cup of vinegar added to a gallon of distilled water will drive the acidity of that water up by a given amount - adding the vinegar - and then observing that the acidity did, indeed, go up by the expected amount. The logical, and most parsimonious, explanation is that the added vinegar caused the rise in acidity. To conclude otherwise would require an explanation for 1) what unknown process(es) neutralized the added acidity of the vinegar and 2) what alternative, unseen constituent(s), alternatively, caused the observed rise in acidity.

To return to the question, "Is nature causing the recent observed decline in global ocean pH?" - The answer is, extremely unlikely. Currently, there are no known natural explanations for the observed decline in GLOBAL AVERAGE ocean pH, and, there is one, clear human-caused explanation (note the global bit is important - there is natural local variation in pH but we are concerned with global shifts).

Captain, if your ship were to suddenly take on water and you could identify a clear leak in the hull (one the size that would explain the amount of incoming water) - wouldn't it be negligent to ignore that leak in favor of finding an unseen one?

On Natural Variation of Global Surface Ocean pH -

Direct historical measures of ocean pH (on the scale of millions of years) do not exist. However, scientists have used proxies (e.g., boron isotopes from ancient plankton shells) to formulate reasonable estimates of historic ocean pH.

Pearson and Palmer (2000 Nature) use this technique, and show that global average surface ocean pH has varied over time (though not necessarily cyclically), but that it has been relatively stable over the past 24 million years, ranging from 8.3-8.1. Most importantly, changes in average surface pH appear to be gradual, on the scale of tens of thousands to millions of years. What concerns scientists most about the recent observed, and predicted, changes in ocean pH is that it is extremely - unprecedentedly - rapid (check out Stanford's tutorial of ocean acidification - slide 4 - for a nice visual of this). Scientists predict a change in average surface ocean pH from 8.10 to as low as 7.8 in 100 years, if we continue to pollute as we are now. It is this rapid rate of change that is most threatening to biology because evolution might not be able to keep up with the environmental change.

There have been a few dramatic ocean acidification events in Earth's distant history. These were caused by massive, natural input of carbon dioxide into the ocean (for example from volcanoes). The best studied example is the Paleocene-Eocene Thermal Maximum (PETM) 55 million years ago. As expected, this event was associated with extinction of numerous calcifying organisms. However, because the world was a very different place back then (for example tropical coral reefs did not exist) and because ocean pH was not the only environmental factor that changed (temperature and oxygen availability changed as well), it is not clear what lessons can be learned from these past events.

ACID TEST - The Movie: Why should we care about Ocean Acidification?

2009-08-11T15:45:45Z

Lisa Suatoni, Senior Scientist, New York

I often get asked the question "how will ocean acidification affect our lives ... why should we care?" I find myself talking about impacts to fisheries, declining revenues, and limited seafood choices. And that's accurate - after all, rising ocean acidity impairs shell growth, making it more difficult for shelled animals (like shellfish) to survive, and that will have a ripple effect throughout the entire ocean food chain.

But I have to admit that I'm puzzled by my answer - and its level of practicality - because it doesn't completely resonate with me. It's not that I don't care about shellfish, or fisheries, or my annual summer lobster feast - because I do. In fact, much of my professional effort goes towards maintaining healthy, sustainable fisheries in the United States.

It's just that when I think about why I really worry about ocean acidification - how it affects me personally - a different answer comes to mind.

I think about the dismay I felt last year when I took my kids snorkeling for the very first time on a coral reef in the Caribbean. I think about my kid's utter delight at seeing a sprinkling of colorful fish and the occasional curious sea turtle, and about my horror at the terribly degraded condition of the reefs. I found myself faking enthusiasm a lot that week during those snorkels. I didn't want to spoil their exhilaration with the reality that the reefs were a fraction of their former glory. This was the first time that I could so clearly see how my generation is denying the next of some of the great wonders of nature, and it was deeply disturbing. There are many local causes for coral reef decay (e.g., overfishing and sediment runoff from coastal development), however the mounting stress from ocean acidification may well be terminal.

Ocean acidification is a second impact of rising atmospheric carbon dioxide concentrations and the process is surprisingly simple. About ¼ to 1/3 of the carbon dioxide emissions from the burning of fossil fuels is absorbed by the seas. As carbon dioxide enters the ocean, it reacts with sea water to form an acid. This acid poses a very direct stress to organisms with shells, as it is corrosive. However, it presents a physiological stress to a range of other organisms as well. Since the industrial revolution, the oceans have become 30% more acidic. If we continue to pollute as we are now, ocean acidity will more than double by the end of the century.

NRDC explores the phenomenon of ocean acidification in a new film, ACID TEST: The Global Challenge of Ocean Acidification - which will premiere on Discovery's Planet Green tomorrow, August 12 at 10:30 pm eastern (and re-airs throughout the month). With narration from Sigourney Weaver and interviews with leading scientists in the field, this film not only explains the science of ocean acidification and its implications for life on earth, but it also tackles the often less discussed ethical dimensions of its impacts.

After viewing ACID TEST, Bruce Steele, the commercial fisherman interviewed in the film said "how can a message so terrifying be made so beautiful?" His comments capture a fundamental message of the film: we are not only threatening the health of marine ecosystems and fisheries worldwide, we are putting the vast beauty of the ocean at grave risk.

For local show times and more information go to: http://www.nrdc.org/acidtest

Acid Test - The Movie

2009-06-09T04:15:31Z

Lisa Suatoni, Senior Scientist, New York

In honor of World Oceans Day, Discovery T.V.'s Planet Green released the trailer of NRDC's new documentary on ocean acidification today (world premiere will air on Discovery Planet Green in August).

The story of ocean acidification is especially appropriate for World Oceans Day because it is a cautionary tale of how the oceans often suffer from our terrestrial bias, the 'out of sight - out of mind' phenomenon, and the very real challenges of ocean science and its chronic underfunding.

For decades we have heard much about how rising atmospheric CO2 concentrations is causing global warming. However, carbon dioxide pollution is having a second effect of making the oceans more acidic (30% more acidic so far - to be exact). The truth is the CO2 problem is more faceted than scientists first led us to believe.

The process of ocean acidification is simple. The excess carbon dioxide from the burning of fossil fuels is not only stored in the atmosphere, it is also stored in the oceans (in fact, approximately ¼ of it -so far 500 billions tons - goes into the sea). As carbon dioxide reacts with ocean water, it forms a weak acid, carbonic acid.

This increasing acidity challenges ocean life on a few fronts. First, it reduces the availability of carbonate - a building block of sea shells. This results in slower growth rates and weaker shells in shelled organisms. If acidity goes high enough, shells literally dissolve, making the ocean uninhabitable to some creatures. This is a big deal because tens of thousands of marine species have carbonate shells or skeletons (not just our favorite seafood). Therefore the effects have implication for marine food webs. Second, increased acidity poses a physiological challenge to ocean life generally (i.e., even to animals without shells), making it more difficult for organisms to breathe and therefore carry out the daily activities necessary for survival.

It is clear that ocean chemistry is being altered on a scale not seen for tens of millions of years, and will likely present profound challenges to many forms of marine life in the coming decades. Ocean acidification is a global challenge on par with climate change.

So why are we just, now, learning about it?

The answer to that question differs depending on who you are talking to.

In actualilty the very scientists who alerted us to the phenomenon of global warming were well aware that a large proportion of the fossil fuel CO2 was going into the world's oceans. In their 1957 paper on the green-house effect, Revelle and Seuss discuss the beneficial aspects of this phenomenon from the perspective of global warming. By removing CO2 from the atmosphere the oceans moderate the green-house effect.

While scientists were aware of this 'service' that the oceans were providing, they seemed less concerned about its implications for ocean chemistry and biology.

There are numerous explanations for this blind-spot:

'Seeing is believing' and it was considerably more difficult to measure the fossil-fuel CO2 signal in the ocean compared to the atmosphere. As a consequence, there was no 'Keeling' curve for the oceans.
Similarly, measurements of ocean pH sufficiently accurate to detect the changes in pH resulting from fossil-fuel emissions were difficult. It was not until the past 10-15 years that scientists were able to measure that the oceans had already undergone large changes in pH since pre-industrial times. Even now, there are very few 'time series' (or repeated measurements at specified locations) showing changes in ocean pH over time.
Few scientists imagined that fossil-fuel production would be as rapid as it was. Even initial 'worst-case scenario' projections of fossil-fuel consumption were overly optimistic.
Marine biologists did not realize that many marine species were sensitive to small changes in ocean pH. Many shelled creatures are negatively impacted much before ocean acidity reaches levels of shell dissolution. An entire science is now burgeoning in this area.

In short, largely because of the challenges presented by ocean sciences (high variability in the ocean environment, lack of permanent monitoring stations, increased cost of sampling and observation, and difficulty in rearing organisms) and its chronic lack of funding, a global - and profoundly important - phenomenon managed to slip by, largely unrecognized for decades.

Acid Test, the movie, aims to raise people's awareness of this phenomenon and warn people of its threat to ocean life. The film delivers two clear messages: now is the time for rapid reductions in fossil fuel consumption and we can no longer continue to take ocean health for granted. Establishing a national (and ultimately global) ocean monitoring system, which can measure important indicators like pH, is a necessary first step to improving ocean health.

Good News for Ocean Acidification Policy

2009-04-24T16:55:09Z

Lisa Suatoni, Senior Scientist, New York

Finally we have some good news on the ocean acidification front.

Three important advances were made in the past few weeks in the United States which indicates that Congress and the Obama administration get the very serious threat that ocean acidification poses for the health of our oceans and the productivity of U.S. fisheries (and fisheries globally).

First, the National Research Council of the National Academy of Science has assembled a 12-member panel to develop an integrated national science and monitoring strategy for ocean acidification. This strong team of scientists headed by the eminent chemist from Princeton, Dr. Francois Morel, had their first meeting last week and aim to produce a report in about a year.

Second, President Obama signed into law the Omnibus Public Land Management Act of 2009 (H.R. 146) (pg 1164) which not only directs the federal government to develop a comprehensive, interagency research plan for ocean acidification but also calls for the necessary funds for its successful execution. If appropriated, over 90 million dollars will be provided to the National Ocean Atmospheric Administration (NOAA) and the National Science Foundation (NSF) over the next four years. This Act will essentially jump-start a badly needed national research program on ocean acidification and support the group of dedicated and underfunded researchers who helped to bring this important problem to our attention. In addition, it will bring the United States in line with international research efforts already underway (see EPOCA).

Third, in response to a petition from the Center of Biological Diversity to revise the marine pH water quality criterion, the Environmental Protection Agency recently published a Notice of Data Availability in the Federal Resister (public comments are due June 15th). The EPA's intent is to consider whether a criteria revision is warranted at this time. A final decision is expected a year from now.

All of these efforts underscore the fact that ocean acidification is not a peripheral issue. It is a second, global impact of rising atmospheric carbon dioxide concentrations. The carbon waste problem is more multidimensional than we realized and this sleeper-issue needs some immediate attention. Funding a coordinated research effort is a necessary first step to tackling this issue.

The Oceans Can Not Wait

2009-02-03T16:02:33Z

Lisa Suatoni, Senior Scientist, New York

Last week a group of 155 scientists signed the 'Monaco Declaration' of ocean acidification and presented one of the most succinct and compelling arguments of why we need to begin curbing carbon dioxide emissions - immediately.

Ocean acidification is a second global impact of rising atmospheric CO2 concentrations (in addition to climate change). Approximately one third of all anthropogenic (man-made) CO2 emissions is absorbed by the oceans. This CO2 immediately becomes an acid in water, and increases the acidity of the oceans. Since the industrial revolution, average acidity of ocean water has increased by 30%. This change in ocean chemistry makes it more difficult for shelled organisms (e.g., crabs, lobsters, oysters, sea urchins, corals and some phytoplankton) to build their shells. If emissions continue on a business as usual trajectory, ocean acidity will approach triple the pre-industrial levels by the end of the century. At these levels, many species or organisms - particularly shelled organisms - will struggle to survive.

The argument in the Monaco Statement is built on six undisputed observations and one highly likely prediction (#4):

1. Ocean acidification is underway.

2. Ocean acidification is already detectable.

3. Ocean acidification is accelerating and severe damages are imminent.

4. Ocean acidification will have socioeconomic impacts.

5. Ocean acidification is rapid, but recovery will be slow.

6. Ocean acidification can be controlled only by limiting future atmospheric CO2 levels.

7. There is still time to act if serious and sustained actions are initiated without further delay.

Two points are worth emphasizing: 'severe damages are imminent' and 'recovery will be slow'.

At current CO2 emissions rates, large regions of the polar oceans will become corrosive to shells of key organisms (base of the food chain) in the next 20-30 years and they will no longer be able to survive in these regions. When atmospheric CO2 concentrations reach double the pre-industrial level (560 ppm) - which could very well happen by mid-century - the erosion of coral reefs will out-pace their growth and they will likely go extinct globally (or certainly in the reef-building form that we know them). This prediction is based on empirical observations of coral calcification rates. The timing of the prediction might vary by decades but the phenomenon and outcome is not in dispute. Tipping points for other calcifying organisms exist but they remain unknown.

If carbon emissions are not stabilized during this century, it will require thousands of years for the oceans' chemistry to return to current conditions. And it will be hundreds of thousands to millions of years for coral reefs to return.

The phenomenon of ocean acidification is simple. It is undeniably caused by human activities, and there is relatively little variation in model predictions compared to climate change. The Monaco Declaration reveals a growing concern and strong consensus among ocean experts: we are now at the cusp of severe and essentially permanent damage to marine ecosystems and we must act now.

Oceans in a High CO2 World

2008-10-09T20:58:52Z

Lisa Suatoni, Senior Scientist, New York

Today, Prince Albert II of Monaco, along with a number of secondary school students and teachers of the principality, are attending The Second International Symposium in a High CO2 World, a conference on ocean acidification.

The site of the meeting is the oceanographic museum built by Prince Albert I in 1910 which stands as an utterly breathtaking symbol of Monaco's enduring commitment to the marine environment.

They have joined 250 scientists from around the world to learn the most up-to-date knowledge on the rapidly emerging global threat of ocean acidification and to discuss necessary policy actions.

Only four years after the very first meeting on the topic - during which scientists widely adopted the term 'ocean acidification' and embarked on a world-wide cooperative research effort - scientists have made impressive advances in our knowledge of the topic.

Over the past four years researchers have:

generated clear predictions of what pH changes will occur in the world's oceans given different carbon emissions scenarios (In other words, we now have a pretty clear idea of how much, where, and when ocean pH will change, given certain fossil fuel emission scenarios.)
identified which ecosystems are going to experience changes first and most dramatically (Antarctica, the Arctic, and eastern boundary upwelling systems like the west coast of the United States)
identified which ecosystems and communities are likely to be most vulnerable (coral reefs - both tropical and deep water)
established that organisms around the globe are already experiencing the stress of increased acidity
improved our understanding that there will be 'winners' and 'losers' in the changing oceans and who they may be ..... (For example, in addition to corals, coralline algae which help to 'glue' coral reefs together will likely suffer dramatically, as will many types of echinoderms such as starfish, sea urchins, and sea cucumbers. On the other hand, there appears to be variation in the response of ecologically important phytoplankton species, such as coccolithophores, (i.e., some showing signs of stress and some not) suggesting that perhaps some species will be able to adapt - or that some species-rich communities may avoid collapse by shifting their composition.)

The scientific accomplishments are impressive. However much remains to be done - not the least of which is the establishment of chemical and biological monitoring in key vulnerable and rapidly changing areas. Little can be done without a 'Keeling' curve for the changing chemistry of the seas.

Two aspects of science and policy were evident from this meeting.

First, when scientists coalesce around a set of questions and work cooperatively, a lot can get done. A handful of talented and dedicated researchers have successfully elevated this global issue to the international policy arena (as evidenced by the mention of ocean acidification in the most recent IPCC report and some discussion of the issue in meetings leading up to COP15). Policy makers need to sustain the momentum on this topic.

Second, when a major research initiative is supported by government, as was done by the European Union with EPOCA, scientific progress is substantially faster.

The United States has yet to allocate dedicated funds to the study of ocean acidification (note: a bill addressing this concern (HR 4174), introduced by Rep. Thomas Allen, passed in the House in July 2008 but the Senate companion bill, introduced by Senator Frank Lautenberg (S1581) has not yet passed) and this is evident by a comparatively smaller research effort in the U.S. A major U.S. commitment is needed to ensure that this critical research field is brought out of its infancy.

The proceedings from the Second International Symposium in a High CO2 World will be published in a special issue of the journal Biogeosciences.