Planning Questions Persist Over Sea Level Rise

Heavy surf along the Monterey Peninsula. Photo: Craig Miller
Heavy surf along the Monterey Peninsula. Photo: Craig Miller

Speakers at this week’s sea level planning conference in Oakland cited everybody from H. L. Mencken to Yogi Berra (“You can observe a lot just by watching”). But the primary insight from the event may have been courtesy of Robert Frost: “…miles to go before (we) sleep.”

About 225 representatives from industry, government and academia gathered at the behest of the non-profit Bay Planning Coalition.  The effort was to push forward a planning agenda to help prepare the Bay Area and coastal California for rising sea levels due to the changing climate. There is considerable uncertainty surrounding how much sea level rise we should expect in the decades to come. There were indications at the conference that planners were starting to coalesce around predictions of 16 inches by 2050, and 55 inches by 2100, projections embraced by the state’s formal climate adaptation plan.

Greater still is the uncertainty surrounding how governments, businesses and public agencies will respond to the challenge. Estimates are that rising seas threaten $100 billion of “economic assets” statewide, half of which are in the Bay Area. While most speakers seemed to agree on the urgency of mobilizing a coordinated planning effort, few seemed certain where to start.

The palpable frustration in the room was voiced  by, among others, Calla Rose Ostrander, Climate Action Coordinator with the City and County of San Francisco. “I think we’ve set ourselves up to need certainty, to make decisions,” she told me, saying that public agencies in charge of roads and development feel paralyzed. “When we apply for funding for these things,” explained Ostrander, they (potential funders) say ‘How are you planning for it?’ And we haven’t been advised yet on how to plan for it.” That dilemma was echoed by Paul Thayer of the California State Lands Commission: “You can’t engineer for a range of sea level rise,” he said. And yet that would appear to be the task.

Oakland Int'l Airport, like much of the Bay Area's critical infrustructure, lies barely above sea level. Photo: Craig Miller
Oakland Int'l Airport, like much of the Bay Area's critical infrastructure, lies barely above sea level. Photo: Craig Miller

Funding is another area that remains fuzzy, amid all the inter-agency discussions, and one that was not substantively addressed at the conference. It is expected that rising seas will require billions of dollars in infrastructure upgrades. The Port of Oakland, for example, is awaiting the outcome of a study to determine what “perimeter defenses” will be needed to keep runways at Oakland International Airport above water.

Several speakers raised concern about rallying public support to confront a threat that is so diffuse. Will Travis, who heads the San Francisco-based Bay Conservation & Development Commission, predicted that “bringing it home” to households with more immediate worries will be the biggest challenge. And yet we can’t wait, warned Travis. “The longer we wait, the worse the problem becomes.”

Scientists as well as policymakers are pondering how to respond to rising sea levels. Nicole Heller of our content partner Climate Central recently attended a conference aimed at that end of the issue, and wrote about it in the Climate Central blog.

Planning Questions Persist Over Sea Level Rise 16 April,2010Craig Miller

9 thoughts on “Planning Questions Persist Over Sea Level Rise”

  1. > “You can’t engineer for a *range* of sea level rise”

    How about contacting the Sierra Nevada Alliance (“adaptation, adaptation, adaptation”) and asking them how they’d solve Paul Thayer’s dilemma?

    “Evil, unspeakable evil, rose in our midst, and we as a people were too weak, too indecisive, too pusillanimous to deal with it. …”

  2. I was wondering what sea level rise report the conference was using for reference. The Pacific Institute conducted a study of sea level rise and it’s impact on the Bay Area. They were to evaluate the risk of future sea level rise on the California coast and the San Francisco Bay. The study was published as part of the California Energy Commission’s Climate Change Center Report Series. This series is to provide California citizens ready access to climate change research. I was reading the Pacific Institute report when I came across a graphic on page six of the report. The data plot stopped at 2000. It was a 2008 report and later data was available, why was it not used? Not much sea level rise, the updated graphics can be found here:

    1. The Climate Adaptation Strategy issued by the state’s Natural Resources Agency last August, appears to be the reference for most planning discussions. Part II of the document (pp. 18-19) identifies “Anticipated Climate Changes,” including sea level rise of 12-18″ by 2050 and 21-55″ by 2100, depending on the emissions scenario used. An excerpt of the text follows:
      “Over the 20th century, sea level has risen by about seven inches along the California coast. Replacing previous projections of relatively modest increases of sea-level rise for the 21st century, the 2009 Scenarios Project built on scientific findings that became available in the last two years to produce estimates of up to 55 inches (1.4 meters) of sea-level rise under the A2 emissions scenario by the end of this century (Figure 7). This projection accounts for the global growth of dams and reservoirs and how they can affect surface runoff into the oceans, but it does not account for the possibility of substantial ice melting from Greenland or the West Antarctic Ice Sheet, which would drive sea levels along the California coast even higher. Projections of sea level rise under the B1 scenario are still several times the rate of historical sea-level rise, and would barely differ under a stringent “policy scenario” in which global emissions would be drastically reduced. This suggests that while mitigation will be important to minimize many climatic and ecological impacts, adaptation is the only way to deal with the impacts of sea-level rise during the 21st century.12 In short, even on a lower emissions trajectory and without the addition of meltwater from the major continental ice sheets, sea levels in the 21st century can be expected to be much higher than sea levels in the 20th century.”

  3. What? “built on scientific findings that became available in the last two years to produce estimates of up to 55 inches” What scientific findings? Lets hope it was not the IPCC AR4 that has over 5,000 non-peer reviewed references. It looks like more unverifiable models. Models are not scientific findings, they nothing more than the assumptions of the modelers. California Tax payers will be required to pay for a mitigation that is based on assumption not science. We are doomed!

    1. I visited the Hearst Castle recently. The State accepts VISA, MasterCard, American Express and Discover if you want to have a look.

      This is the single most profound reality of coastal California, deliberately swept under the rug by planning committees. A rich man like George Hearst with all the political advantages that money could buy via the Democratic party in San Francisco, and his own privately owned media to influence circumstance to his advantage and yet three generations and 7 inches of sea level later there is no one with the last name Hearst living in San Simeon.
      There is no such thing as private property in this State. Doesn’t matter who you are or what you are worth, it all belongs to the government.

      So now the State operators want to sheer the public of more property in order to preserve their ill gotten gain.

      I say sure lets put it to a vote.

      All in favor of raising taxes on heating oil and transpertation in order to save Barbara Steisand’s scenic shoreline palace from being eroded away say Aye.

  4. Craig,

    I’ve been thinking about your original 4/16 article which I followed from the KQED link. I’ve never blogged before so please bear with me. Just thought I’d throw some stuff your way that might be considered in your intercdhange. Although I was not familiar with the conference, I’ve been following the science relating to global warming for years. I’m fully convinced that the trend is definitely an average rise in temp over the LONG HAUL, and that we may have passed the tipping point because methane is now being released from the oceans and Russia’s permafrost. This gas is a far more efficient heat trapper than CO2 thus, in the years to come, the AIR temp will accelerate upwards at a much higher rate than now resulting in strange and severe changes in climate and weather patterns world wide. BUT for now I want to address just the fascinating data that Russell Steele initially offered, which “strangely” shows that recently the sea level seems to have stabilized.

    Without getting into the incredible complexity of ocean currents, surface reflectivity etc., there are two fundamental things to consider that can explain the “short term” hesitation in sea level rise. Both derive from physics fundamentals.

    The first (the subject of a detailed expose on NOVA about 2 years ago) is so counter-intuitive that it took many years for the science community to accept, while the second is an idea which I just thought of from basic physics for dummies principles. I’ll deal with the acknowledged one first.

    1) Photon flux from the sun hitting the earth.
    Counter to conventional wisdom, the flux of photons, i.e. “sun rays” hitting the oceans (the majority of the planet’s surface) is actually DECREASING while the AIR temp is INCREASING. How can that be? Well several years ago, scientists in different places noted this strange evidence but individual data publications were scoffed at.

    Just two of the initial weird findings were:
    a) in crude experiments looking for water temp rise conducted in the desert outback of Australia, where the skies are mostly cloudless, a pan of water, always filled to the same level with the water of the same temperature, was left out in the sun and periodically checked for water temperature increase due to sunshine. Plotting this for a period of years, they found that the rate of rise of the water temperature was actually DECREASING while the average AIR temperature rate of rise was INCREASING. Hmmm, wazzup? How can you have global warming, with average air temp increasing, but the AVERAGE water temperature was not rising AS FAST as the that of the air. High School physics to the rescue!! In their setup, analogous to the situation for the oceans, the predominant heating of water in the experiment IS NOT due to the hot air around the container (it was insulated on all sides anyway and only the water surface was exposed to the air and sun), but due to the absorption of the sun’s rays, i.e. photons per second incident onto the water’s surface. One way or another, except for a constant average reflection (about 4% at the top surface of the water) the energy goes into raising the temp of the water. Thus the Aussies published the absurd result, not accepted at that time, that the average photon flux from the sun is actually decreasing with time. Solar activity and photon flux measured by orbiting space satellites was taken into account, so it ain’t the sun itself.

    b) Independently, a meteorological survey in the USA to measure AVERAGE air temperatures near the ground at many places around the country showed strange results as well. Average daily temperature was defined simply as half way between the maximum and minimum in a 24hr period. These had been tracked for many years, and showed a pretty uniform increase over time. Then, hey currumba, for a week or so in the fall of 2001 there was a marked INCREASE in average temperatures, of over a degree, everywhere in the US, for about a week. You guessed it!! You may recall that ALL air traffic over the US was halted for about a week starting on 9/11/2001 because of 911. They quickly realized that what may be happening. The skies were notably clearer because the jet vapor trails were gone, and indeed the photon flux hitting the ground (thus heating the air) also increased accordingly.

    Further experiments by many others led to the correct conclusion that there are two opposing factors at work. The “soot” of particles (not the gas CO2) from burning of fossil fuels, fires, and the like, in fact blocks some of the sun’s rays, effectively lessening the heating of the ground and water. However, the greenhouse effect is more efficient so that, on average, air and sea temps are rising, but less than if there were no particle type pollution. The irony is that if we in the US had not cut down of particulate pollution, the rate of rise of the air and water would be higher. Currently, the developing nations (China, India ….) are are producing CO2 in a comparatively dirtier way so they also send along some partial shielding in the form of pollution. Experiments on the Maldives Islands show that, depite sea level rise and higher air and water temps, the photon flux is dramatically lower (compared to elsewhere). This is easily attributable to the very high density of particulate pollution in their upper airspace spewing over from the Indian subcontinent due to the prevailing wind patterns. So perhaps we may have a plateau for a while, until the pollution problem is addressed, but in the meantime CO2 and more importantly Methane, is inexorably accumulating with [unfortunately] positive feedback since, now that Methane will soon dominate over CO2, that gas’s release will self perpetuate at an accelerating rate, or so some of the experts predict.

    2) ANOTHER SIMPLE POSTULATE that may explain sea level [read average ocean temperature] has leveled off for a while. From common experience, we all know what happens when ice cubes float in a fixed volume of water. First think of a pan of water slowly being stirred so that temperatures is pretty uniform throughout, and at a starting temperature of say 50 deg-F in a room with air temp of 70 deg-F. In the absence of an ice cube, the water eventually warms up at an approximately constant, very slow, rate. The water expands and rises in the pan. The analogue is the rising ocean levels observed until very recently.

    Now lets consider two cases, each starting when the water temp is around 60 deg, and where we add an ice cube of known volume before insertion into the water. To make this easy and sneaky, let’s assume the ice cube’s volume is 4% of the volume of water in the pan.

    Case A:
    Start the experiment AFTER the ice cube has been dropped into the pan. The water temp initially is 60F, the ice hasn’t started to melt significantly, the ice floats and the water level has already risen by an amount proportional to the volume of water it displaces, which happens (gee wilikens) to be 96% of the initial volume of ice cube. Ice is 4% less dense than water, which is why it floats. As it melts, it turns into water with a volume of 96% of its initial volume (the amount of water in the form of ice) and to a first approximation, since it is only a small fraction of the total water, the level doesn’t change significantly. BUT, the temp of the water bath does cool UNTIL the ice is completely melted, after which the water continues to increase in temp, expand and raise it’s level, until ultimately reaching 70F.

    This is the analogue of the melting of the Arctic ice which only started significant melting relatively recently. The dominant effect is to cool the oceans and make them LESS salty. These have opposite effects on the oceans. Cooling tends to lower sea level BUT less saline water is less dense which leads to an increase in ocean volume, tending to raise sea levels. No one seems very worried about rising sea levels from Arctic melting (perhaps because these two effects nearly cancel each other) but note that once all the Arctic ice is gone, the temperature continues to rise and the oceans expand again. Until recently, this was the major melting going on because Arctic ice is floating already and started melting earlier than ice sheets on land (Antarctic and Greenland).

    Case B:
    This is basically the same as Case A, except we start before dropping the ice cube into the water bath. This is the analogue of the ice sheets of Greenland and the Antarctic, where the ice sits ON land. Our ice cube would not have melted very fast if it had not been put into the water. Had we held it above the water with wooden tongs (need more ice, honey) so that only melted by contact with the air, the rise in the water level would have been much slower. Greenland and Antarctic ice started significant melting later, but are now calving off huge icebergs at an accelerating and alarming rate because of cracking and surface water seepage down to the bottom of the sheet, which causes the sheets to break and slip off the land into the sea. Just as when we initially dropped the ice cube into the pan of water, the immediate rise in sea level is proportional to (the exact amount is complex and involves ocean volumes etc.) 96% of the volume of ice that breaks off.

    In summary, I think that the warming trend will likely be inexorably upward and, even though local climates become colder in some areas and hotter in others, the average temperature is likely to rise at an increasingly higher rate due to the feedback mechanisms I alluded to earlier.

    Perhaps nature will indeed reverse the trend. The present Iceland volcano eruption will have the effect of cooling the planet a tiny bit temporarily due to blockage of the sun by the ash particles. Apparently, it was much more violent eruptions elsewhere, hundreds of years ago, that caused a series of extremely cold winters in the middle ages. Ironically, a recent theory I read proposes that the reason this latest eruption is so violent and has produced so much ash, may be due to the fact that the volcano was able to bulge up dramatically higher than before (pre-eruption) because the ice sheet over it had thinned out (much less weight) due to global warming. I even read a conjecture that similar occurrences may prompt other volcanoes that are much less icebound than years ago, to erupt earlier than they might otherwise might have, and with enormous ash clouds. Wow!

    1. Methane oxidizes into H2O and CO2 once freed to the atmosphere.

      Planes weren’t grounded long enough to affect the atmospheric aerosol (soot particles) over the US after 9/11. It was less then a day for law enforcement flights. The skies were cleared of commercial flights from about 6 p.m. EST on Sep. 11th to 2 a.m. Sep. 13th, which makes a total of 32 hours. By September 14th 424 of 455 airports in the United States were open for business.
      On Sep 11th the sun rises at 7:53 a.m., sets at 6:26 p.m., which makes about ten hours of sunshine unobstructed by contrails.

      The idea is intriguing, but if water vapor trails from high altitude aircraft could make a perceptible difference, then why doesn’t a 1-3% natural variation in global cloud cover associated with the cosmic ray flux? And if cosmic rays can move the weather like that, what need do we have of co2 to explain the warming of the last century?

      Here’s the median temperature record for Sacramento starting from September 11th 2001
      . in Fahrenheit
      9/11 – 72 degrees; 9/12 – 67 degrees; 9/13 – 70 degrees; 9/14 – 74 degrees.

      From there it drops off. I’m not sugesting this is representative of the entire country. I’m just saying the contrail theory didn’t show itself much here.

      Here’s the Bom 12 month mean temp anomaly map for Australia – depending on what you consider “outback” it doesn’t look too much warmer (this is compared to the 61-90 base line average).

      The waterpan cools off the same way we cool down. It evaporates the heat off.
      No need to delve into the ice cube thing. I appreciate the amount of thought that went into it, but currently the world sea ice anomaly is positive. There is simply more of it then average when compared to the satellite record.

  5. Thanks for this post Craig. ClimateWatch continues to provide good coverage. I am one of the authors of the Pacific Institute study referenced by Mr. Steele above. I wanted to address his comment, one that he’s made before, because he implies that there is some sort of scandal or scientific wrongdoing here, where there is none.

    The figure that Mr. Steele refers to appeared in an earlier draft. The figure in question appeared as Figure 1 on page 6 of the report which is downloadable here:

    The first version of the plot, prepared by NOAA, showed monthly sea levels recorded at the Golden Gate from 1854 – 2000. As we were finalizing the report, NOAA published a new, updated figure that included measurements up to 2006. There was no deliberate exclusion of data; we simply used the latest-version of the graphic that was available. (NOAA sometimes takes years before validating tide measurements and publishing official statistics.) The figure in question is from this website:

    Nothing in either of the figures changes the conclusion that sea levels have risen for the last century. Overall, tides in San Francisco have gone up about 8″ from 1897-2006. There is lots of noise in the data, as tides are influence by many factors, including the 19-year cycle which forms the basis for the National Tidal Datum Epoch, El Nino years, etc.

    As much as we’d all like for this alarming trend to reverse, there is no evidence to support that assertion.

    Even if you don’t believe man’s activities are affecting the earth’s climate, you should believe that seas are rising. If we’re not causing it, then something else is. The evidence for changes in sea level is irrefutable, and includes measurements from hundreds of tide gages around the world and satellites in orbit around the Earth.

    Of course, no one can predict exactly what will happen in the future, but it is reasonable and prudent to begin planning for sea level rise, which is exactly what most architects, engineers, and planners are doing.

Comments are closed.


Craig Miller

Craig is a former KQED Science editor, specializing in weather, climate, water & energy issues, with a little seismology thrown in just to shake things up. Prior to that, he launched and led the station's award-winning multimedia project, Climate Watch. Craig is also an accomplished writer/producer of television documentaries, with a focus on natural resource issues.

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