The Wave. It's the New Pink.

Thanks to Miss Susan Casey's new novel, "The Wave: In Pursuit of the Rogues, Freaks and Giants of the Ocean," waves, HUGE waves, in fact, are all the rage.  I'm pretty sure every night that I turn the television on, Casey is appearing on some different nighttime program to talk about her book and experiences with massive waves. 

Casey's book took her around the world to experience montrous waves like the rougue waves off the south coast of Afirca, storm-born giants in Hawaii, and the biggest wave ever recorded that blasted Alaska in 1958.  Casey travels with people who "enjoy" surfing and playing in these waves as well as interviewing scientists that worry that global warming is going to steadily bring us bigger and badder waves. 

If you did this blog from class on rogue waves and found them especially intriguing, try picking up a copy of this action-packed novel at your nearest bookstore! Caset should really pay me for this...

Clams, Clams, Clams!

Clams

Handful of Quahogs

Hard clams are edible marine bivalve mollusks native to the eastern shores of North America from Prince William Sound to the Yucatan Penninsula.  One of the best known of these hard clams is the Quahog clam, shown in the picture above.  This clam, also referred to as the round clam, is a favorite on the East coast.  Many recommend it be eaten raw or in chowder, but many other recipes exist for this popular clam (see the picture below). 

Stuffed, Baked Quahogs

Quahogs are hermaphrodites, so they are born as males and change to and remain females as they mature.  Smaller versions of the Quahog clam include Littlenecks and Cherrystones (discussed next).  Confusingly, the name "Quahog" also refers to an ocean clam species (Artica islandica) that is of different family of bihalves. 

Ocean Quahog

Cherrystones, as mentioned earlier, are smaller versions of the Quahog clam.  Cherrystones can grow up to 3 inches wide and are named after the Cherrystone Creek in Virginia.  These clams are also typically eaten raw.  In fact they are usually the clams you will get when you order clams on the half-shell.  

Cherrystones

One of my personal favorite clams is the geoduck (pronounced "gooey-duck") clam! This is a very odd looking clam that has even been featured on shows such as "Andrew Zimmerman's Bizzare Foods" and "Dirty Jobs with Mike Rowe."  This clam is related to the giant clam, can have a shell 5-8 inches wide, and can weigh in at over 5 pounds. (Some varieties in the deep ocean have been reported to grow over 100 pounds!!!) The most unique feature of the geoduck -- it's LONG neck, or siphon.  This neck can easily grow to be +3 feet in length.  The geoduck lives deep in the sand and is thus harvested by digging down, sometimes as far as 70 feet deep.  Different parts of the clam are used for different recipes such as chowder and even steaks (clam steaks, that is). 

 Harvested Geoducks at Market

 Diving for Geoducks!!!

 Yay for Geoducks!

What is an Environmental Sensitivity Index map?

An Environmental Sensitivity Index (ESI) map is a very useful tool for organizations wanting to design response and cleanup procedures for a specific coastal area in the event of an oil spill.  The actual map is a diagram depicting a coastline area and the human and biological resources and shoreline sensitivity to an oil spill in that area.  An ESI map is created using geographic information system (GIS) techniques to combine the shoreline map with info on the biological and human resources present in that area.  The resources and aspects on the maps are typically ranked and color coded by their sensitivity to an oil spill. 

The figure below shows an ESI map for the San Diego Bay and it's vicinity as provided by NOAA. 

As you can see the map is color coded and uses different symbols and pictures to depict different human and biological resources and animal species.  



All About Ice!

Both the North and South polar ice caps play a huge role in the Earth's hydrologic cycle.  The ice caps have existed for millions of years and their fluctuations in size have direct affects on life on Earth.  At least 5 times during the Earth's history the ice caps have expanded both north and south towards the equator and remained there for around a million years.  These phases are known as ice ages.  In more recent history, the yearly fluctuations of the ice cap sizes determines how much water is locked into the ice caps and therefore how much free water is flowing through the World Ocean (thus affecting the mean sea level). 

Below are pictures of the North and South polar ice caps.

North Pole (changes in extent between 1979 and 2003)

Thermal View of South Pole (Antarctica)

When large pieces of ice are either melted or broken off of the ice caps, icebergs are formed.  Icebergs are giant free-floating packs of ice that are larger below the surface than above (typically only one ninth of the iceberg is shown above water).  A beautiful picture of an iceberg during sunset off the coast of Newfoundland is shown next. 

Iceberg during sunset around Newfoundland

Icebergs can also make fairly interesting noises as they move and pass each other.  Such sounds are documented and examples can be heard in the video provided through the link below.  *Noises get really interesting at 1:26!!!

Noisy Icebergs

Below is a map produced to show the extent of ice present around the North Pole in both the winter (left) and summer (right).  This image was created using the SSM/I (Special Sensor Microwave/Image) on the DMSP series of Department of Defense satellites.  The black dot on the images represents the North Pole.  As you can see, the ice extends much further south into the Atlantic, throughout North America and Europe, during the winter than it does during the summer. 



Light Attenuation for Various Colors of Light in Water

A light's wavelength is directly related to how deep the light can penetrate a body of water.  As light travels through water, it is scattered and absorbed by the water molecules, ions and particulates in the water.  The decrease in light intensity over distance is referred to as attenuation. 

Beer's Law can be used to determine how much of a light source reaches what depth of water based on its wavelength and corresponding attenuation coefficient.  Based on the attenuation coefficients for red, orange*, yellow, green, blue and voilet light, their calculated % Incident Light versus Depth of Water are shown below in Figure 1.  All colors start at a % Incident Light of 1% because the natural log cannot be taken for 0%. 

Figure 2 shows the same information but on a logarithmic scale to yield straight lines. 

*Note: Two coefficients were given for the color range of orange so the graphs show lines for an Orange1 with a coefficient of 0.650m^-1 and an Orange2 with a coefficient of 0.350m^-1. 

 Figure 1

Figure 2

As the figures suggest, as a light's wavelength increases (red has the largest wavelength, violet has the smallest) the light is attenuated more quickly.  Hence, colors like red and orange attenuate much faster than blues and violet.  

Bisphenol A (BPA) and the Environment

Info: "Bisphenol A: Information Sheet." E Safety

Bisphenol A (referred to as BPA) is a chemical used in the manufacturing of polycarbonate plastics and epoxy resins.  Needless to say, huge amounts of BPA are used every year around the world and releases into the environment are inevitable.  Some environmental exposure comes from actual releases from industrial effluents and biological wastewater treatment plants.  Dust particulates and vaporized BPA are also produced, but their impacts are minimal (the vapor is rapidly degraded by sunlight).  Based on the properties of BPA, about 50% of BPA in the environment has the potential to bind to soils and sediments and the rest remains in the water column.  Other sources of BPA in the environment include the adsorption from plastic in the marine environment or leachate from landfills.  As more plastic is thrown away or discarded of in nature, more and more BPA is filtered into the environment.  This is a potential hazard because BPA has been proven to affect different organisms' reproduction and estrogen cycles. 

Floating Island of Plastic



Affects of Aerosolized Brevetoxins from Florida Red Tide on Healthy Workers

Article: Backer, Lorraine C. et al. "Occupational Exposure to Aerosolized Brevetoxins during Florida Red Tide Events: Effects on a Healthy Worker Population." Environmental Health Perspectives 113.5 (2005).

This article covers a study conducted to see how the aerosolized brevetoxins released by the Karenia brevis dinoflagellates in a Red Tide affect a healthy person's respiratory and pulmonary health.  The effects of the brevetoxins on humans after being consumed in shellfish tissue has been well documented in the past, but the effects from environmental exposures, such as being in aerosol form were uncertain.  The studied focused on 28 full-time lifegaurds along Florida's gulf coast because they were healthy and their beaches did not close during red tide events -- causing them to work onshore and even stay in the lifegaurd towers at least 6 hours every shift.  An occupational, epidemiological study was constructed to determine the respiratory effects of a red tide and if mild outdoor exercise during a red tide decreased pulmonary performance or increased self-reported symptoms. 

Red Tide

The results of the study showed an increase in self-reported upper respiratory problems and headaches during exposure to the brevetoxins from the red tide (but not an increase in lower repsiratory problems).  Pulmonary effects were present, but not significant. 

El Nino and La Nina

Article: Philander, S.G.H. "El Nino and La Nina." Journal of the Atmospheric Sciences 42.23 (1985).

This article provided me with alot of technical information on how El Nino and La Nina work together and make up the Southern Oscillation.  The term El Nino refers to a period in which the sea surface water temperature is HIGHER than normal in the eastern Pacific Ocean.  This period accompanied by a high air surface pressure in the west Pacific.  As El Nino's complement, La Nina refers to a period in which the sea surface water temperature is LOWER than normal in the east Pacific.  La Nina also includes a low air surface pressure in the western Pacific.  The atmospheric components of these cycles is known as the Southern Oscillation.  Meterologic and oceanographic characteristics, including pressure, temperature, precipitation, wind stress and sea level are all affected by El Nino and La Nina.  Their individual effects are highly complementary of one another.  The picture below depicts the drastic differences between water temperature during an El Nino event and a La Nina event.  El Nino is shown in the top left globe, while La Nina is pictured in the bottom right globe. 



Bathymetric Maps and Hypsographic Curves

Bathymetric maps are maps that represent underwater depths (in oceans, seas, or lakes) at specific coordinates as topographic maps show elevation at specific locations on the Earth's surface.  Most bathymetric maps show isobaths (lines of equal depths) as contours for the body of water.  This gives a person an idea of how the basin of the body of water is shaped. 

Similar to bathymetric maps, hypsographic curves show a relationship between the Earth's surface and water depth (or elevation).  However, unlike bathymetric maps, a hypsographic curve shows a relationship between elevation or underwater depth and the amount of Earth's surface covered.  For example, if a hypsographic curve existed for a lake of interest, and one wanted to know what the surface area of the lake would be if the water level dropped to a specific depth, say 10 feet, the curve could be used. 

In class, we created a hypsographic curve from a given bathymetric map of a lake ranging from 0-11 feet in depth.  Using a square cutout of the scale (representing 10,000 square meters) and precise cutouts of the lake following each depth contour, the area at each depth was determined through a weight-area relationship (0.103 grams = 10,000 square meters).  Next, the hypsographic curve was created in Excel by plotting the areas on the x-axis versus the depths (in reverse order with 0 meters at the top of the graph) on the y-axis.  The resulting curve is shown below in Figure 1.

Another useful curve shows lake volume as a function of water depth.  This sort of graph can easily be created from a hypsographic curve.  First, the change in depth between two data points (surface to 1 meter down, for example) must be determined.  Then the recorded surface areas at the two points can be averaged and multipled by the change in depth, resulting in a volume in cubic meters.  The midpoints for each change in depth are the plotted on the y-axis in reverse order versus the volumes on the x-axis.  The volume vs. depth graph for the bathymetric map given in class is shown below in Figure 2.

Using the volume graph, one can also determine the total volume of a body of water.  To do so, the total volumes at each depth range from surface to the deepest point are added together.  This is a very easy calculation is the data is set up in Excel.  The total volume of the lake used in class was found to be 820,728 cubic meters. 

Namena Marine Reserve, Fiji

This is a picture of the coral reef in the Namena Marine Reserve in Fiji. The Reserve consists of two main reefs named Grand Central Station and the Chimneys. For more information on the Namena Marine Reserve visit:

http://www.namena.org/