One in six people receive most of the protein in their diets from the oceans, which are facing unprecedented threats as carbon emissions rise. Food insecurity among those who depend upon seafood as a critical part of their diets is expected to increase along with carbon emissions. Meanwhile, overfishing, low-oxygen dead zones and coastal degradation are complicating matters. UN agencies and other organizations are scrambling to grasp the scope of how climate change is affecting oceans and what can be done to mitigate its implications for food security.

Finding Food Security in Climate-changing Oceans

By Matthew Berger | July 16, 2013

In early June, the United Nations held its fifth annual World Oceans Day. While many recent efforts have focused on finding ways to address the food needs of a growing human population affected by climate change, the majority of this work has revolved around terrestrial food production. Much less attention has been devoted to adapting marine food production to a new climate. Perhaps that is why this year’s World Oceans Day theme was “oceans and people.”

oceans-security-1Andrew Hudson, Head of the UN Development Program (UNDP)’s Water and Ocean Governance Program, speaking at a press conference on the impacts of climate change on ocean ecosystems, in February 2012. (UN Photo/Paulo Filgueiras)

“From trade to food to climate regulation, the oceans are integral to all of humanity. This is particularly so for coastal dwellers whose income and culture are irrevocably bound to the sea,” Secretary-General Ban Ki-moon said in commemorating the day. “If we are to fully benefit from the oceans, we must reverse the degradation of the marine environment due to pollution, overexploitation and acidification.”

One in six people receive most of the protein in their diets from the oceans, which are facing unprecedented threats as carbon emissions rise. Food insecurity among those who depend upon seafood as a critical part of their diets is expected to increase along with carbon emissions. Meanwhile, overfishing, low-oxygen dead zones and coastal degradation are complicating matters. UN agencies and other organizations are scrambling to grasp the scope of how climate change is affecting oceans and what can be done to mitigate its implications for food security. 

In Hot Water

On land, excessive emissions of carbon dioxide and other greenhouse gases have led to more frequent droughts, heat waves, severe weather eventslonger warm seasons and warmer high elevations. Yet in the oceans, these emissions have had two main effects: warmer surface waters and more acidic water.

oceans-security-4A photo from the “Oceans” photography exhibition currently on display at the United Nations in New York. ©Monica Schipper Photography.

Just as air temperatures have been rising on average, temperatures of the ocean’s surface waters have been increasing. This has led to more stratification between the warmer surface waters and colder, deeper waters. Such a trend is expected to continue, according to a study published last year in the Journal of Geophysical Research, with an “increasing degree of decoupling between the surface and the deeper oceans, with important consequences for many biogeochemical processes.”

One of the most important processes this “decoupling” could affect is the upwelling of cold, nutrient-rich waters from the depths to the upper waters where most sea life feed and live. The authors of that 2012 study noted that some of the largest stratification changes are occurring at and affecting this crucial upwelling process in some of the planet’s most productive fishing grounds.

“Thus, the projected stratification changes could have a large impact on phytoplankton and the broader food web,” the study concluded.

Alarming Acidification

But carbon emissions are impacting the food web even more directly—and rapidly—through ocean acidification. Oceans absorb about half the carbon emitted into the atmosphere, some of which then forms carbonic acid. As the oceans’ acidity increases, shell-forming organisms—from tiny plankton to oysters and corals—find it increasingly difficult to build the carbonate shells they need to survive. These organisms are being impacted by climate change, as are the animals that eat them and the people eating those animals.

Already, oceans have become 30 percent more acidic since the start of the Industrial Revolution, and they could become 150 percent more acidic by the end of the century. A study last year found only one point in the past 300 million years when oceans changed at the rate they are today—a period about 56 million years ago when atmospheric carbon doubled over roughly 5,000 years, leading to extinctions among both animals unable to form carbonate shells and animals that depended upon them.

oceans-security-2A view of the General Assembly Hall in December 2012, as the Assembly adopted a wide-ranging resolution on “oceans and the law of the sea,” emphasizing sustainable development and the maintenance of biodiversity in marine ecosystems. (UN Photo/Ryan Brown)

The researchers estimated that ocean pH may have fallen by as much 0.45 units over that period. Today, pH has fallen by 0.1 units in just the past 100 years, which that study’s authors said is at least 10 times faster than the acidification that took place 56 million years ago.

The Intergovernmental Panel on Climate Change has projected that acidification could drop pH levels by another 0.3 to 0.4 units by the year 2100. Indeed, the science of ocean acidification is all the more distressing because of how robust and precise it is.

According to Andrew Hudson, head of the water and ocean governance program at the United Nations Development Programme (UNDP), “[Atmospheric] climate models can only go so far; that is not the case with ocean acidification. We know exactly how much is going in and what sort of impact it is having.”

No Easy Solutions

The impact of that acidification on humans is harder to forecast. Still, it is clear that shellfish and animals dying off at the bottom of the food chain—or fish populations relocating to follow shifting warmer waters—will have repercussions all the way up to humans.

If fish populations in the North Atlantic move to more northern or deeper waters, and new species previously unknown that far north move in, North American and European fishing fleets would likely have the capacity and money to adapt through new gears or vessels. Similarly, if, say, Pacific Northwest oyster farmers feel the pinch of more acidic waters ruining their crops of seed oysters—as is already happening—they would likely be able to grudgingly afford to adapt by adding an antacid to their waters.

oceans-security-3A photo from the “Oceans” photography exhibition currently on display at the United Nations in New York. ©Monica Schipper Photography.

However, the majority of the one in six people who depend most heavily upon fish and shellfish for their diets are some of the poorest on the planet. Their ability to adapt to changing waters and fish populations will be severely constrained.

report last fall by the nonprofit group Oceana ranked countries based on the threat that carbon emissions pose to their ocean-based food security by looking at countries’ dependence upon seafood, the vulnerability of their local waters to acidification and warming, and their capacity to adapt to these changes.

The island nation Comoros ranked as the most threatened, followed by Togo, and then two more island nations—Cook Islands and Kiribati. Among major countries, Pakistan and Thailand ranked as the eighth and 10th most threatened. China ranked 35th.

The report notes that while some regions will see increases in fish numbers, “losses of up to 40 percent of catch potential can be expected in the tropics. Nations without large industrialized fishing fleets will be unlikely to follow these shifting resources around the world.”

What can be done to help seafood-dependent nations mitigate or adapt to warmer, more acidic seas? “It’s pretty cut and dry,” said UNDP’s Hudson. “The only viable option right now is to reduce emissions.”

Glimmers of Hope

Although the UN Framework Convention on Climate Change’s (UNFCCC) process aiming to reduce emissions has been slow, the UN community has been tackling the impacts of carbon emissions on ocean-based food security in various ways, with glimmers of hope.

Last November, UNDP issued a report with the Global Environment Facility that argued that $5 billion in public investment would catalyze enough action and additional public and private investment to reverse marine degradation, including that caused by greenhouse gas emissions.

Meanwhile, UNESCO’s Intergovernmental Oceanographic Commission has been taking a leading role in assessing the impacts of climate change on oceans, including working with developing countries to craft adaptation strategies. And just last month, the General Assembly’s informal consultative process on oceans, which identifies areas on which international cooperation should be increased, made ocean acidification its topic for the first time, a development that UNDP’s Hudson praised.

“It’s a start, but only the beginning,” Hudson said, reiterating that “ultimately, we cannot slow down ocean acidification without cutting emissions.” That four-day blitz of acidification presentations and discussions followed World Oceans Day.

In calling global attention to reversing oceanic degradation, the Secretary-General also urged countries to join the Law of the Sea—the United States and a handful of other countries remain the only holdouts. Doing so could provide some legal frameworks for addressing ocean acidification and other contributors to the destruction of marine environments on which billions of people depend.

http://www.theinterdependent.com/environment/article/finding-food-security-in-climate-changing-oceans

– See more at: http://www.theinterdependent.com/environment/article/finding-food-security-in-climate-changing-oceans#sthash.FwNSu0uq.dpuf

 

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: