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Few of our planet's residents have managed to adapt to their environmental niche as gracefully as the Brown Pelican. Imagine for a moment your typical river salmon, who spends their entire existence struggling against raging river water  currents, slowly hopping up rapids until they get eaten by a bear. Think of a seagull, now, or a crow. Surely you have been in a storm and seen the foolish foul flying straight into the wind, making either no progress or even getting blown backwards and landing with negative displacement from their starting point. Rather than fighting with the forces of nature as many animals do, the Brown Pelican has managed to develop ways of harnessing these dynamic forces of nature --that is, moving air and water, or "wind" and "waves"--in ways that actually make their lives easier.   One of the most fascinating ways that the species accomplishes this goal is by gliding just in front of ocean swells, such that they are being donated additional lift by updrafts that naturally occur in this region. The pelicans essentially "surf" waves by funneling, or "compressing" these updrafts between their wings and the water--a phenomenon known as "compression surfing." This goes hand in hand with the so-called "ground effect." Ground-effect refers to the observation that birds such as skimmers and pelicans are able to maintain gliding at a constant altitude for longer periods of time without additional energy input (through flapping) when near the water's surface than when farther away (Hainsworth 431-444). Ground effect in relation to compression surfing can be thought of as the work done (by updrafts associated with the frontside of moving ocean swells) in allowing a pelican to fly at a constant altitude without flapping. My intention in writing this paper is to model a pelican "compression surfing" and make quantitative conclusions about the prescence of "ground-effect" in this phenomenon.   
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The density of air is a known constant, roughly 1.2 kilograms per meter cubed. g is the gravitational accelleration constant which is exactly 9.8 meters per second squared.$\ k$, the wave number, is defined as$\ 2pi$/$\lambda$. Two meters of swell ($\ h = 1$meter)at a period$\ T$ of eight seconds describes the common tradewind based ocean swell; such a swell would have a wavelength given by $\lambda$ =$\ v_{ph}T$ =$\ gT^2/(2pi)$ $\approx$ 100 meters and speed$\ v_{ph}$ $\approx$ 12.7 m/s, with$\ k = pi/50$. Primarily we'll use a low wind speed, 1 m/s. This will make calculations easier and will give us something to compare to if we want to plug in a higher wind speed (still within the domain of the work function, obviously) to see which gives the pelican more benefit. I'm sure some math could be done to find the optimal wind speed for compression surfing. Regardless, back to our problem: plug in these numbers and it is easy to see that under the deep water dispersion relation$\ v_{z}(x_{o}, z_{o}, t_{o})$ =$\ 2.8(10^-3)$    An ancient creature, estimates have it that this majestic bird has been cruising the skies for at least thirty million years. Historical geologists would call this period of time the "Oligocene epoch" of the "Paleogene period," but to the rest of us these implications can be put in much simpler terms--Pelicans are dinosaurs! Perhaps it is to this that the Brown Pelican owes its aerial expertise. Thirty million years has allowed evolution to take its course, and over the generations the pelican has been able to develop the artform of "compression surfing." Sources Cited:  Schnell, Gary D.; Hellack, Jenna J. “Flight Speeds of Brown Pelicans, Chimney Swifts, and Other Birds.” \textit{Bird-Banding} - Spring 1978 - Vol. 49, No. 2. Pg(108-112):  Wei Shyy, Hikaru Aono, Chang-kwon Kang, Hao Liu. \textit{Cambridge Aerospace Series}: An introduction to flapping wing aerodynamics. ch 1. pg(1-40). Cambridge University Press. Avenue of the Americas, New York, USA. Published 2013.  Prepared by: Department of the Interior - U.S. Fish and Wildlife Service. “Brown Pelican; Pelecanus occidentalis”. (entire article). U. S. Fish and Wildlife Service Endangered Species Program. 4401 N. Fairfax Drive, Room 420, Arlington, VA, USA. January 2008.  Prepared by: Department of the Interior - U.S. Fish and Wildlife Service. “Brown Pelican Proposed Delisting Questions and Answers”. (entire article). U. S. Fish and Wildlife Service Endangered Species Program. 4401 N. Fairfax Drive, Room 420, Arlington, VA, USA.   \textit{J. exp. Biology}: pg (431-444). Hainsworth, F Reed. Induced Drag Savings from Ground Effect and Formation Flight in Brown Pelicans. Department of Biology, Syracuse University, Syracuse, AT, USA. Accepted 21 October, 1987. Printed in Great Britain © The Company of Biologists Limited 1988.