Great Decision 2012: The future of the ocean

How can we save the world?  What can an average Joe Blow on the street like us, without a colossal wad of cash to pay nefarious lobbyists, do to nudge the ship of state in the right direction? One answer, not very sexy but  more effective than just changing your light bulbs, is active participation in democracy. What I mean is all that civics-class stuff like writing your Congressperson–heck, calling your Congressperson on the phone to give her/him a healthy dose of the Vox Populi.

To do this effectively, though, there is one catch: it helps to know what you’re talking about. It will be painfully clear to many of our faithful readers how infrequently this is the case among American voters. Take the fact that American voters do or verey recently did seriously consider as Presidential candidates individuals who advocate moon colonies (umm, leaving aside what the business plan is, how will we feed them?) and pizza executives whose stump speeches plagiarized Pokemon: The Movie (Oh, if only I were making this up).

Enter the Foreign Policy Association. This organization promotes the truly radical idea that progress comes from informing people about the issues of our day and discussing them rationally. The Great Decisions, as they call them. To their credit, the FPA has recognized that one of the Great Decisions we face in 2012 involves the future of the world ocean.

Yesterday I gave the first of two presentations to a group of citizens as part of the 2012 Great Decisions program.  Here is the gist of my presentation. It all starts in a galaxy far, far away. When astronauts visited another heavenly body for the first time in the late 1960s, we got a wholly new and breathtaking perspective on this planet:

The blue planet from the vantage of its moon, first seen during the Apollo missions

As vividly shown by the early moon landings, the  most striking feature of the Earth is that it is blue. The Water Planet, as Jacques Cousteau was fond of calling it. And so it is.  What does all that blue do for us? The oceans — or more accurately the tiny plant cells that abound in surface waters — literally create the oxygen we breathe — half of it anyway, with the other half coming from land plants. The ocean moderates the climate and provides transport. But perhaps the most obvious service the ocean provides is upwards of $200 billion in fisheries and related industrial activity:

Those fisheries supply important protein to a large fraction of the world’s population, especially in the developing world. But that productivity — thought as recently as the 1940s to be inexhaustible, is reaching its limit, even as the human population continues its upward trajectory in numbers and appetites.

The world has reached the point of "peak fish".


Indeed, The United Nations’ Fisheries and Agricultural organization, which undertakes a comprehensive assessment of the the status of global fisheries every four years, reports that the proportion of overexploited, depleted or recovering stocks (harvested fish populations)  increased from 10 percent in 1974 to 32 percent in 2008. Slightly more than half of the stocks  were fully exploited and, therefore, their current catches are at or close to their maximum sustainable productions. The remaining 32 percent were estimated to be either overexploited (28 percent), depleted (3 percent) or recovering from depletion (1 percent) and, thus, yielding less than their maximum potential production owing to excess fishing pressure in the past. This combined percentage is the highest in history.

More than 70% of global fish stocks are at or above the maximum harvest sustainable rate.


And it’s not just the giant commercial factory ships. It’s us! The recreational fishers too!

"Trophy" fish from Florida charter boats: Then and Now


Even the cartoonists get it!Part of the reason we’re able to do so much damage is cheap energy. For the last century or more, human society has run on fossil fuel. This has produced unimaginable increases in productivity and standard of living for people almost everywhere. But it’s come at a high cost that we are only now realizing. The carbon released by digging up coal and oil out of the ground and burning them is turning the earth’s atmosphere into a greenhouse hothouse.

Burning fossil fuels has turned the earth's atmosphere into a hothouse


And we know what happens in a hothouse:

Temperature of the atmosphere, averaged over earth's surface, has increased steadily


The rising temperatures on land are well known. But climate heating is also affecting the world’s oceans in a host of ways, including rapidly melting ice caps that are raising global sea levels, causing a scramble for mineral rights in the Arctic, and increasing stratification of surface waters that reduces productivity.

Major acceleration of climate-related change in oceans over last few decades


Just because much of the ocean is out of sight, it should not be ot of mind. We’ve learned in recent decades that the oceans are a critical element of both the global climate stabilization systems as well as a major producer of dietary protein for humanity. We’ve also learned that the rapidly growing global population of us on earth is reflected in a wide range of ocean impacts:

Consequences of a rapidly growing global population for the oceans


Take my backyard, the Chesapeake Bay. As in many other shallow coastal waters (and even some deeper ones) throughout the world, oxygen-poor waters — nicknamed “dead zones” because most animals can’t live in them — have spread at an alarming rate in recent decades. This phenomenon is ultimately caused by excess nutrients pouring into the coasts from agricultural fertilizers, septic outwash, sewage, and runoff. But the dead zones are made worse by hot temperatures, which stratify the water column and prevent mixing of oxygen from the surface donw into the deep basins:

Low-oxygen "dead zones", here in Chesapeake Bay, aggravated by warming


Heating of the atmosphere and waters admittedly will have some positive outcomes. For example, longer growing seasons will allow higher productivity on some places. But the response to changing tenmperatures is often complex and not gradual. For example, many plants and animals are living near their upper thermal limits and can be pushed over the edge by a small rise in temperature. Corals are a classic example. But the same is true of eelgrass, the underwater plant that once carpeted large areas of the Chesapeake as well as estuaries and coasts throughout the northern hemisphere.  Eelgrass has declined precipitously since the mid 20th century in the Bay (and elsewhere) but the hot summers of 2005 and 2010 came close to dealing it the knock-out punch. Why? Probably because the temperatures past a tipping point. Eelgrass basically shuts down above roughly 30 degrees C, and those two years had unusually large numbers of days above that threshold:

Climate-mediated seagrass decline: Evidence for a tipping point?


This is important because many coastal fishes depend on the habitat protection and rich productivity of submerged vegetation, particularly when they’re young.

Eelgrass and other seagrasses are the foundation of productive coastal ecosystems


But there’s another side of rising ocean temperatures that affects us much more directly. New Orleans — and the world– got a rude awakening in September 2005 when hurricane Katrina hit and we got a taste for the dark side of a wild climate. Katrina was a turning point of sorts in public perception of climate change, which is ironic since it’s not clear that man-made climate change had anything to do with Katrina. In fact it remains uncertain whether the intensity or frequency of storms will increase as the world warms.

But several things are certain: average temperature is rising, sea level is rising, and wave heights are increasing. All of these will put pressure on the coastal margin for both coastal people, habitats, and economies



New Orleans was vulnerable because it is is so low-lying. But there were aggravating factors. A fundamental one was the precipitous loss of coastal wetlands as a result of river channelization, development, and perhaps oil drilling, during the 20th century. Louisiana lost a chunk of wetlands the size of Delaware during that period!

Tremendous loss of coastal wetlands contributed to the severity of Katrina's impacts


A quantitative analysis of hurricane damages in the US, based on a large number of storms, has shown that economic damage was lower in areas with large acreage of protecting wetlands:

Costanza's calculations of how hurricane damage related to area of buffering wetlands


In fact, the combination of wind speed and wetland area was the best predictor of economic damage to areas hit but hurricanes in the US over the last century, with these two factors explaining 60% of the variation among areas. The authors concluded that coastal wetlands provide $23 billion in storm insurance in the US each year:

So what happens to essential coastal infrastructure when the big one hits?


More generally, how do we reconcile the conflicting demands for waterfront property, a fossil-fuel-based lifestyle, and prosperity  — with human freedom, to put it in the most basic terms  —  with the equally critical requirements for food, clean air, and water for ourselves and the life forms we share this uniqe planet with? There are no easy answers. But someone has to make the Great Decisions. who will it be — We, the People? Or the 1%?










Leave a Reply