Exploration of the Seas
Exploration of the Seas

Author: National Research Council

Publisher: National Academies Press

Published: 2003-11-04

Total Pages: 228

ISBN-13: 0309166802

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In the summer of 1803, Thomas Jefferson sent Meriwether Lewis and William Clark on a journey to establish an American presence in a land of unqualified natural resources and riches. Is it fitting that, on the 200th anniversary of that expedition, the United States, together with international partners, should embark on another journey of exploration in a vastly more extensive region of remarkable potential for discovery. Although the oceans cover more than 70 percent of our planet's surface, much of the ocean has been investigated in only a cursory sense, and many areas have not been investigated at all. Exploration of the Seas assesses the feasibility and potential value of implementing a major, coordinated, international program of ocean exploration and discovery. The study committee surveys national and international ocean programs and strategies for cooperation between governments, institutions, and ocean scientists and explorers, identifying strengths, weaknesses, and gaps in these activities. Based primarily on existing documents, the committee summarizes priority areas for ocean research and exploration and examines existing plans for advancing ocean exploration and knowledge.

The Leatherback Turtle
The Leatherback Turtle

Author: James R. Spotila

Publisher: JHU Press

Published: 2015-10-30

Total Pages: 246

ISBN-13: 142141709X

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The most comprehensive book ever written on leatherback sea turtles. Weighing as much as 2,000 pounds and reaching lengths of over seven feet, leatherback turtles are the world’s largest reptile. These unusual sea turtles have a thick, pliable shell that helps them to withstand great depths—they can swim more than one thousand meters below the surface in search of food. And what food source sustains these goliaths? Their diet consists almost exclusively of jellyfish, a meal they crisscross the oceans to find. Leatherbacks have been declining in recent decades, and some predict they will be gone by the end of this century. Why? Because of two primary factors: human redevelopment of nesting beaches and commercial fishing. There are only twenty-nine index beaches in the world where these turtles nest, and there is immense pressure to develop most of them into homes or resorts. At the same time, longline and gill net fisheries continue to overwhelm waters frequented by leatherbacks. In The Leatherback Turtle, James R. Spotila and Pilar Santidrián Tomillo bring together the world’s leading experts to produce a volume that reveals the biology of the leatherback while putting a spotlight on the conservation problems and solutions related to the species. The book leaves us with options: embark on the conservation strategy laid out within its pages and save one of nature’s most splendid creations, or watch yet another magnificent species disappear.

New Strategies for America's Watersheds
New Strategies for America's Watersheds

Author: National Research Council

Publisher: National Academies Press

Published: 1999-04-28

Total Pages: 333

ISBN-13: 0309064171

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Emergence of a toxic organism like pfisteria in tributaries of the Chesapeake Bay has focused public attention on potential hazards in our water. More importantly, it has reminded us of the importance of the entire watershed to the health of any body of water and how political boundaries complicate watershed management. New Strategies for America's Watersheds provides a timely and comprehensive look at the rise of "watershed thinking" among scientists and policymakers and recommends ways to steer the nation toward improved watershed management. The volume defines important terms, identifies fundamental issues, and explores reasons why now is the time to bring watersheds to the forefront of ecosystem management. In a discussion of scale and scope, the committee examines how to expand the watershed from a topographic unit to a framework for integrating natural, social, and economic perspectives as they share the same geographic space. The volume discusses: Regional variations in climate, topography, demographics, institutions, land use, culture, and law. Roles and interaction of federal, state, and local agencies. Availability or lack of pertinent data. Options for financing. The committee identifies critical points in watershed planning to ensure appropriate stakeholder involvement and integration of science, policy, and environmental ethics.

Radar Detection of Turbulence in Thunderstorms
Radar Detection of Turbulence in Thunderstorms

Author: Alan R. Bohne

Publisher:

Published: 1981

Total Pages: 68

ISBN-13:

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Theoretical investigations are undertaken to relate intensity of turbulent air motion to Doppler radar spectrum mean and variance in precipitation environments. Examples of theoretical radar derived turbulence power density spectra and total precipitation motion variance show that effects due to imperfect particle response are significant for turbulence scale lengths less than 250 m. Doppler spectrum variance and estimated eddy dissipation rate (epsilon) are found strongly dependent upon precipitation environment for ranges less than about 20 km, and for cases where the turbulence outer scale length (lambda) is less than 0.5 km. They are also found to be essentially independent of lambda when the maximum pulse volume dimension is less than 1/2 lambda, and independent of range but strongly dependent on lambda at ranges where the maximum pulse volume dimension is greater than lambda. Estimation of epsilon by radar is shown to be unreliable until a method of remotely determining lambda is found. Nevertheless, classification of turbulence severity (index = cube root of epsilon is possible with only a reasonable guess of lambda. Analyses of aircraft/gust velocity data indicate that thunderstorm turbulence is localized into discrete patches, and that such localization must be accounted for when aircraft gust velocity data undergo power spectrum analysis.