Light Attenuation in the Ocean

As light travels through the water column, it is absorbed and reflected by objects that are in the water, like dissolved sediments, ions, and by water molecules themselves. The decrease in surface light at a given depth in the water column is called "Light Attenuation". Light attenuation is an important factor for autotrophic organisms that which depend on a specific wavelength of light to photosynthesize food. These organisms are limited in how deep they can live depending on their specific wavelength of light, as some wavelengths can travel deeper than others. Shorter wavelength high energy waves, such as blue and violet, travel much deeper in the water column than longer wavelength low energy waves, such as red and infra red. Light attenuation is calculated by multiplying the incident (surface) light by the exponential of negative attenuation constant (different for every wavelength) and the depth (in Meters). Written out, Iz= IoE(-KZ). Figure 1, shown below, is a graphical representation of several wavelengths of light and their percent transmittance (amount of remaining surface light) at a given depth.

Journal Articles

El Nino and La Nina
Article: "Impact of El Niño / Southern Oscillation on Low-flows in South Georgia, USA". Pierre G.F. Gerard- Marchant and David E. Stooksbury. Southeastern Geographer 2010 p. 218-243

Purpose and Results: This research takes a look at the influence of the El Nino/La Nina weather patterns influence on several streams in Georgia. Several streams in Georgia were evaluated at different times of the year and evaluate the effect of the weather patterns on the low-flows of the streams. Gerard- Marchant and Stooksbury found that the low-flows were lower in the months of the El Nino/ La Nina climate events and higher in the neutral months of the year such as November to April.

Red Tide

Article:"Implications of Harmful Microalgae and Heterotrophic Dinoflagellates in management of sustainableMarine Fisheries". JoAnn M. Burkholder.  Ecological Applications 1998 p. 37-62

 Purpose and Results: This article looks at the many types of  Dinoflagellates that cause harm to fish and lists the toxins they produce. Red tide can be a very big problem in a fishery due to the large amount of fish produced there and the intended use of those fish, feeding a population. Burkholder goes on to note that Dinoflagellates and Red tide can," Accumulating evidence indicates that these harmful species significantly affect marine fisheries at the population level, well beyond the obvious acute impacts of fish kills" (p. 54). This shows that Marine fisheries can be in great danger not only due to lost fish, but also a threat to its potential consumer.

Figure 1. Web map of Red Tide toxin in fish.  (Borrowed from Burkholder)

Burkholder goes on to state that there is a need for the Red Tide toxins to be identified and an economical means of testing and remediation need to be researched.

Hypsographic Curves: What are they and how are they useful?

A Hypsographic curve is a graphical representation of the depth of a body of water at certain intervals.Hypsographic curves are used to understand the depth and the curvature of a lake or a pond. The volume of the lake can also be garnered from the hypsographic curve by averaging the layers or slices of the curve.
Chart 1 is the plot of depth vs. area of a Lake

                                                                           Chart 1
Chart 2 is the depth vs. volume of the same lake

                                                                        Chart 2
Want to have fun making your own Hypsographic curves of your favorite lakes or ponds?! Then click HERE!! 

The Artifical reef, USS Oriskany

About 22 miles off the coast of Pensacola Florida coast, covered by over 200 feet of water lies the USS Oriskany. The USS Oriskany was a aircraft supercarrier used in the Vietnam conflict and the Korean war, seeing over 12,000 combat missions. The carrier suffered a large fire on October 26, 1966 when a flare ignited a weapons bay and took the lives of 44 men. The Oriskany was decommissioned ten years later and was slowly cannibalized for parts until 1995 when it was sold for scrap. After being sold for scrap the supercarrier was towed to the coast of Florida, where the enormous task to clean up the carrier for its future use.

The USS Oriskany was made, in 2006, the largest man-made reef in the world. Now commonly known as "The Mighty O" or "The Great Carrier Reef", the Oriskany is now a tourist site for recreational divers. I would like to go see the remains of the Oriskany in a dive. This is the place that I want to visit the most because of the types of fish that can be seen living in the carrier. I also think that the preparation work required to convert the carrier from war machine to fish habitat is also astounding due to the size of the Oriskany. Below is a video of the sinking of the Oriskany done in 2006. The other is a video of the the Oriskany looked like only after two years of being on the sea floor.

                                                            VIDEOS!!
She sinks http://www.youtube.com/watch?v=1TNK0GM3OvU
The Great Carrier Reef http://www.youtube.com/watch?v=Cz8NvE_mi9I

All pictures courtesy of Wikipedia and all video courtesy of youtube