by Kevin Tuerff
Oil-free Emerald Coast of Northwest Florida (6/10)
I’ve spent the last two weeks hanging out along beach communities of northwest Florida and Long Island, New York. With the BP oil blowout disaster in the Gulf of Mexico, I’ve been curious to see what people were thinking, and especially if the disaster had changed their attitudes about the need for America to reduce our dependence on oil through investment in clean energy for our transportation.
I took every chance I could to eavesdrop on public conversations at coffee shops, book stores, on the beach. Here’s my non-scientific summary of what I heard:
1. Despair abounds. Most people seem to know plugging the hole may be months away, but they invest a lot of energy into the daily attempts being reported by BP and government agencies. Although the northwest Florida beaches were beautifully clean, the media panic is keeping many people away. I overheard vacation home owners, small business proprietors, and fishing tour captains talk about the immediate negative impact on their pocket books. All they had was a hope BP would consider their claim for their loss as “legitimate.”
2. If we can’t see it, we can’t grasp the big problem. For weeks, the public was kept from seeing the live video feed of the ocean floor where the oil is spewing like a volcano into the sea. During that period, many had a feeling of, “well, it may not be so bad.” That sentiment continued for weeks as the oil floated off the Louisiana coast. Aerial images and newsroom graphics tried to explain the projected path of the oil.
Only a few TV news reporters have attempted to capture video from underwater areas where the oil slick lingers in the Gulf. It will likely be years before we know the toll of the oil on tourism and oil industries, numerous animal species, marshes, sand dunes, coral reefs, bays, and estuaries.
You have to wonder if the response would have been different if the darker crude oil were bubbling up quicker, hitting the shores heavier. Some mistakenly believe the light crude coming up is less toxic to wildlife and the environment.
3. Americans could be talked into greater public investments in clean energy, but they are frustrated with the president and Congress. Some folks I talked to were Democrats who voted for Obama. Even they admit they are cynical about any major legislative action to move beyond the status quo of dirty fossil fuels.
Many pundits have complained, “We know more about the surface of the moon than we do about the surface of the ocean.” Certainly NOAA has only a fraction of NASA’s budget. Do the government agencies allowing deep-water drilling know all they need to know to continue this practice without another disaster? If Americans knew more about offshore drilling, would they support or oppose growing this practice?
Here is an important glossary of oil spill terminology from the National Oceanic at Atmospheric Agency.
Oil Color and Appearance Terms
Oil slick from Perdido Key, Florida (6/12/10)
Dark (or True) Color: Represents a continuous true oil color (i.e., its natural color), commonly occurring at thicknesses of at least a hundredth of an inch (or, a little over a tenth of a millimeter). Oil thickness at this “dark” stage (especially in a calm and/or contained state) could range over several orders of magnitude. At sea, however, after reaching an equilibrium condition, most oils would not achieve an average thickness beyond a few millimeters. Heavy fuel oils and highly weathered or emulsified oils (especially on very cold water) could, of course, reach equilibrium states considerably greater than a few millimeters.
Metallic: The next distinct oil color, thicker than rainbow, that tends to reflect the color of the sky, but with some element of oil color, often between a light gray and a dull brown. Metallic is a “mirror to the sky.”
Sheen: Sheen is a very thin layer of oil (less than 0.0002 inches or 0.005 mm) floating on the water surface and is the most common form of oil seen in the later stages of a spill. According to their thickness, sheens vary in color from rainbows, for the thicker layers, to silver/gray for thinner layers, to almost transparent for the thinnest layers.
Transitional Dark (or True) color: The next distinct oil on water layer thickness after metallic, which tends to reflect a transitional dark or true oil color. At the “Transitional” stage, most of the oil will be just thick enough to look like its natural color (typically a few thousandths of an inch, or few hundredths of a millimeter), and yet thin enough in places to appear somewhat patchy.
Oil Structure/Distribution Terms
Convergence Zone: A long narrow band of oil (and possibly other materials) often caused by the convergence of two bodies of water with different temperatures and/or salinities. Unlike windrows and streamers, commonly associated with wind, convergence zones are normally associated with the interface between differing water masses, or with the effects of tidal and depth changes that cause currents to converge due to density differences or due to large bathymetric changes. Such zones may be several kilometers in length and consist of dark or emulsified oil and heavy debris surrounded by sheens.
No Structure: Random eddies or swirls of oil at any one or more thicknesses. This distribution of oil is normally the result of little to no winds and/or currents.
Patches: An oil configuration or “structure” that reflects a broad range of shapes and dimensions. Numerous tarballs could combine to form a patch; oil of various colors and consistency could form a patch or single layer 10s of cm to 10s (or even 100s) of meters in diameter; and a large patch of dark or rainbow oil could have patches of emulsion within it. Patches of oily debris, barely able to float with sediment/plants in them, might be called “tarmats,” circular patches at sea might be called “pancakes”; really big patches might simply be called “continuous” slicks. But, they are all “patches.”
Streamers: Narrow bands or lines of oil (sheens, dark or emulsified) with relatively clean water on each side. Streamers may be caused by wind and/or currents, but should not be confused with multiple parallel bands of oil associated with windrows, or with convergence zones or lines commonly associated with temperature and/or salinity discontinuities.
Tarballs: Discrete, and usually pliable, globules of weathered oil, ranging from mostly oil to highly emulsified with varying amount of debris and/or sediment. Tarballs may vary in size from millimeters to 20-30 centimeters across. Depending on exactly how weathered, or hardened, the outer layer of the tarballs is, sheen may or may not be present.
Windrows: Multiple bands or streaks of oil (sheens, dark, or mousse) that line up nearly parallel with the wind. Such streaks (typically including seaweed, foam, and other organic material) are caused by a series of counter rotating vortices in the surface layers that produce alternating convergent and divergent zones. Sometimes referred to as Langmuir vortices (after a researcher in 1938), the resulting “windrows” begin to form with wind speeds of approximately six knots or more.
Over the next several months, both the Enviroblog and the Green Detectives will focus more on the importance of our oceans, both terminology, science, and policy. Check back often or subscribe for RSS updates.