Seascape Projects

Just a quick note on our sea surface monitoring project. We are working with a group in Ensenada, Mexico to apply our camera system (designed for oil spill mitigation) to a red tide monitoring project. The images below show a dry run, so there is no red tide present, but stay tuned. If this project gets off the ground, it would be a neat application of our system.

Original photo

There is still substantial and vigorous debate within the scientific community about global climate change.  --Not really on whether or not it's occurring, nor really about the general importance of carbon dioxide and other contributions by humans.  Rather, the debate has more to do with the particulars.  For example, why does the Arctic appear to be melting faster than forecasted?  Which species will be the winners and losers as the climate changes?  How will sea-level-rise impact beach barrier systems?  These, and hundreds of other questions, comprise the scientific dialogue.

On the flip side is the public perception of climate change.  This arena is a mix of scientific information, political agendas, sensationalism, ideology, fund raising, personal experience, and charismatic megafauna.  Naturally, we can't expect the entire populace to always listen to and give due respect to scientific discipline.  (That only happens when we're designing weapons.)  There are so many sources of information that must be filtered--the scientific literature is only one such source.

For those looking for new lenses through which to view the topic of climate change, I'd like to draw attention to futures markets, or prediction markets.  A futures market is one in which investors can buy or sell shares in the outcome of a certain event, such as an election.  If your prediction turns out to be accurate, you get a return on your investment. The idea is to tap into what is known as the "wisdom of crowds," as well as people's desire to make money.  These markets turn out to often be excellent tools for predicting future events.

Futures markets are now being used to try to predict the consequences of climate change.  It's a way of getting people to put their money where there mouth is when it comes to global warming.  A nice discussion of this idea can be found here.  I'll just include this image, swiped from www.intrade.com, that shows one such market in action.

Since top-10 lists are so last decade, I've decided to summarize SeascapeModeling's 2009 as a reverse top 7 list:

7 presentations (Ecological Society of America, Society for Marine Mammologists Biennial, Gulf of Maine Symposium, GLOBEC Open Science Meeting, Right Whale Consortium Meeting)

6 months of mostly operational copepod & right whale forecasts

5 invited lectures (Southern Marine Community College, Louisiana State University, Marine Environment Research Institute, National Science Teachers Association)

4 poster presentations (Gulf of Maine Symposium,  Society for Marine Mammologists Biennial, SMS Grad Student Symposium)

3 graduate students (Pete, Dan, Nick)

2 post docs (Fred and Eli)

1 new Ph. D. **

**pending final edits to the dissertation

Andy's concerns about discriminating wisely between trend and noise, between low-frequency and high-frequency signals in time series of environmental variables (Air temperature in his example), apply as well to measurable quantities in ecosystems. Particularly relevant is the phenology of the species, which defines the timing of crucial recurrent events of their life cycle, like the date of first arrival to the nesting ground, the date of germination, the date of mating, the date of blooming etc. You may have noticed that I used examples related to birds and plants. Well, while phenology is a general concept, an empirical knowledge patiently accumulated by bird lovers and Sunday gardeners of the 19th and 20th centuries was first to be translated into systematic scientific surveys. And following rigorous statistical analyses of those long time series of observations, it has been firmly established that changes in the phenology of most species accompanied trends in temperature. The strength of the correlation is all the more important as the seasonality (latitude) of the ecosystem and the dependance of the species to their environment increase. The connection with climate change issues is straightforward. And it is not just about how one species or another will cope with changes of its environment, but rather about the interlocked interactions between all those species.

If you can easily think at a beautiful tulip as a species embedded in its environment, it is the same, in a more dynamic way, for planktonic marine species. Now oceanographers begin to benefit of the fruits of several long lasting monitoring programs. Unfortunately, the ever increasing pace of global climate change means that oceanographers are required to draw firm conclusions about the impact of environmental variability on ecosystems and develop predictive capabilities in the meantime ! And this will remain an elusive target as long as the mechanisms gearing those changes are not understood properly. Daunting task, as the changes in timing of such major event as diapause entrance and exit emerge form several layers of physiological and behavioral processes obeying their own dynamics while interacting with each others. But impossible is not known at the EML, so we decided to model the mechanisms behind the diapause of the dominant copepod Calanus finmarchicus. We already know that even if it can produce several generation a year, this critically important species thrives in its seasonal environment (Northern half of the North Atlantic) thanks to its diapause strategy, which means killing time at depth in order not to be killed by the detrimental conditions prevailing at the surface in winter. For this purpose, it makes a feast on large phytoplankton cells (mainly diatoms) during the short period they are available, and build up impressive amount of energy rich lipid reserves. Those swimming droplets of lipid are in turn the basis for the rest of the upper trophic levels.

And what about changes then ? Things are more sparse there... Records of physiological properties related to the diapausing strategy are about a decade old now. Not enough really to study trends on climatological scales, but enough to understand that interannual variability is high (see figure). But abundance data are enough to see changes, especially in areas localized at its biogeographical fringe. In the North Sea for example, the ecosystem shifted from a copepod population dominated by 80% of C. finmarchicus before the 60's to a present state dominated by 80% of its southern congener C. helgolandicus. What is the role of diapause in that ? Not known yet. One thing is certain though: changes occur at an ever accelerating pace, and the unforeseen consequences for the ecosystems are likely to appear before our eyes while we are still racing to improve our understanding. I strongly wish that Copenhagen "talks" will end up with agreements as legally constraining on our leaders than the climate changes will be actually constraining on us.

Superimposed to the climatological (2004-2008) relative abundance of the different copepodid stages are box plots of the estimated dates of initiation (late winter) and termination (summer) of diapause in Calanus finmarchicus in the Gulf of Maine. Data from UNH COOC WB-7 station. Figure from James J. Pierson.

"Have you been outside today? It's 60 degrees in late November. I mean there's a Christmas Tree in front of this building and guys are wearing flip flops. I mean, you can't say this isn't real."

For those who missed it, here's the link to Al Gore's "Out-crazy the crazy" approach to dealing with climate change and other environmental problems:



The way we've ignored these dangers, and in some cases clung to denial, does border on crazy.

Okay, it's been a while since I wrote about the topic of diapause in our preferred species around here, the famous Calanus finmarchicus (Take no offense, right whale...it's your favorite food anyway). But I promised model results and, hey, it takes a while to write a bunch of equations that make sense and, on top of that, without bugs ! I can ensure you, numerical bugs are no more pleasant than the one you would fight franticly while fishing the trout during a nice day of June on a Maine river...
So here is a presentation taking the issue of the control of diapause by the lipid metabolism in Calanus finmarchicus where this blog entry left it. Enjoy it !

lipid_and_dormancy_Calanus.pdf

As part of my ocean photogrammetry project, I've installed a live camera taking time lapse photography of Portland Harbor.  The objective here is to test a low-cost live monitoring system for surface slicks (i.e. oil).  The images can be georectified on the fly, giving a latitude-longitude position of everything we can see on the surface of the water (see image).

Right now, I've set the website up to show the last twenty minutes of images in an animation.  The next step is to show an animation of the rectified images along side the original.  Stay tuned for this exciting update.


Georectified photographs of Portland Harbor. This figure shows two photos taken
from different angles, overlaid on the same portion of the harbor.


Image from the live Gull's Eye camera.  Click here for animation of current images.

SeascapeModeling has been on the road.  Last week, Nick and I traveled to the RARGOM Gulf of Maine Symposium in St. Andrews, New Brunswick.  We're now at the Society for Marine Mammalogists Biennial meeting in Quebec City.  Nick and Dan presented various aspects of our copepod-right whale modeling work.  I presented something completely different.  

For the last several years, I've been sketching diagrams, scribbling equations, and filling spreadsheets trying to figure out whether whales are like trees, at least when it comes to carbon dioxide. Seriously. Yes, I know I need a life, but this is actually really neat.  Here's how it goes:

Forests are an important reservoir of carbon on land.  Through photosynthesis, trees take carbon dioxide out of atmosphere and turn it into tree (leaves, roots, and wood).  When the carbon is locked up as tree it is no longer in the atmosphere, reducing the greenhouse effect.  This is why businesses (at least in Europe) can get carbon credits by helping preserve forests.  As a forest grows, more carbon is taken out of the atmosphere.  Conversely, if a forests burns, the carbon gets released as carbon dioxide.

In the ocean, most of the photosynthesis takes place in single celled phytoplankton.  These cells may live a few days or weeks, so they can't really store carbon.  Instead, carbon in the ocean is stored in the bodies of larger organisms.  As the largest and longest lived animals, whales act like the trees of ocean (minus the leaves). Whaling, like a forest fire, turned hundreds of years worth of whale-carbon and returned it to the atmosphere.  Since industrial whaling stopped in the 1970s, most whale populations are now recovering and are storing more carbon.

Large fish, notably tuna and sharks, can similarly store carbon for many years.  However, even including these species, the amount of carbon stored by marine vertebrates is small compared with the total amount of forest on land.  But, whales (and large fish) have one more trick.  Once a forest becomes mature, its ability to store carbon decreases.  While there is an upper limit to how much carbon can be stored in living whale, whale populations can continue to export carbon as dead whales.  Whales have few predators, so many of the whales that suffer "natural" deaths will sink to the bottom of the ocean.  If the whale dies in deep water, its carbon will remain out of the atmosphere for thousands of years.  The amount of dead whales is related to the total number of whales, so whaling reduced the size of this carbon "sink".  By estimating the total decline in the mass of whales, assuming that whaling turned whales into carbon dioxide, and accounting for the lost "dead whale export potential", I calculated that the total carbon footprint of 100 years of whaling released an amount of carbon dioxide to the atmosphere equivalent to setting New England on fire.  The full paper, (including equations!) is here.

Yesterday, I went for a dive at the Rachel Carson Salt pond up in New Harbor, Maine. Down around 90 feet, much of the light in the visible spectrum (~400-700nm) has been attenuated. Basically, this means that the light is absorbed as it passes through water. Think about sitting under a tree on a sunny day with the sun directly overhead: the bigger the tree, and the more leaves between you and the sun, the more stuff the sunlight needs to pass through to reach you, which means less direct light reaches you under the tree. But were you sitting under a short tree with fewer leaves, more light reaches you directly, since there's less stuff in the way. The leaves on the tree are like particles in the water and the deeper you swim, the more particles there are between you and the sun (i.e. there's more stuff in the way).
  What makes this phenomenon neat, is that different colors of light are absorbed and scattered by the particles in the water at different rates, so, for example, at 90 feet, things all look pretty blue/green since the red light is absorbed/scattered faster than the blue/green light. To illustrate this, I took 2 pictures of a northern red anemone (Urticina felina) at 90 feet (or ~27m): one with natural light and one with a flash. The flash is akin to letting the sun shine directly on the anemone in the photograph, that is the red light hasn't been absorbed yet, since the light source is less than 1 ft (~.3m) from the subject.