Planet Ocean
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National Park Service Point Reyes National Seashore U.S. Department of the Interior PLANET OCEAN How inappropriate to call this planet Earth when it is quite clearly Ocean. Arthur C. Clarke NASA 2011 Visible in the foreground is the island of Andros in the Bahamas, surrounded by azure-colored shallow waters, looking out to the continental shelf and the deeper blue of the Atlantic Ocean. Why We Live Here Imagine you are flying in gigantic cosmic explosion called the “Big may have prevented them from becoming Bang.” The origin of earth’s water is not liquid water worlds. Venus is closer to the Sun, from a distant galaxy to our solar system. You entirely known but several theories exist and Mars farther from the Sun than Earth. come through the icy debris of the Kuiper to explain it. As our planet coalesced out Venutian water may have boiled off because its Belt, past Neptune and Uranus, on by the gas of this dust cloud, it grew very hot, and surface temperature is so hot. Martian water giants, Saturn and Jupiter. Then, after making volcanic eruptions happened frequently. The may once have flowed, but now is thought to it through a belt of asteroids, you hover over eruptions brought water to the surface as well be locked up as ice, mostly below the planet’s little, red, rocky Mars for a look. Next you see as magma. The earth’s gravity increased and rocky, red surface. a lovely, bright blue orb partially shrouded in more water from the inner solar system was white clouds. It looks like no other place in captured by our growing planet. In addition, So we live on this blue planet—because life, the neighborhood. What gives it its distinctive comets—largely made of ice—collided with the as we know it, requires liquid water to form. look? young Earth. These are proposed sources are By three billion years ago, the ocean basins liq Liquiduid water.water proposed for Earth's water. were filled with water to about their current depths, and the first living things probably Billions of years ago according to most Our nearest planetary neighbors, Venus and formed in warm, shallow, ocean water. Inside, scientists, Earth materialized out of collisions Mars had similar formative experiences, but you can learn more about our oceans and our of dust, gas, and water that resulted from a the position of their orbits around our Sun connections to them. Inside Page Why The Ocean Matters 2 Please use caution when Visit the Point Reyes In The Zone 2 recreating near or in Lighthouse, walk the Land And Water In Motion 3 the Pacific Ocean. The stairs and get a stamp to The Bottom of the Food Chain 4 Point ReyesSAMPLE beaches TEXT are prove you did it! Journeys 5 subject to rip currents Humans And Oceans 6 and rogueSAMPLE waves TEXT that Page 8 has activities for Food For Thought 7 pose significant dangers. kids and you can collect Out At The Point 7 some animal stamps! Kid’s Activities 8 Page 1 Why The Ocean Matters 1. The Earth has one ocean with many basins. O 2. The ocean covers about 70% of the Earth’s surface, 1 and contains about 97% of the Earth’s water. 3 2 CO 4 3. Half of Earth’s oxygen is produced in the sunlit ocean layers, and half of the carbon dioxide in the atmosphere is absorbed by the ocean. It’s the blue heart of the planet — and we should 4. Most rain, the source of much of our 5 drinking water, comes from the ocean. take care of our heart. It’s 6 what makes life possible 5. The ocean is a major influence on weather and climate. for us. 6. The ocean and ocean life shape the —Sylvia Earle shoreline features of the Earth. 8 7. Life in the ocean is diverse. The smallest known virus and the largest animal live in 7 the ocean. 8. Many geologic and geochemical cycles begin in ? the ocean. 9 9. Most of our knowledge of the ocean comes from shallower waters. Less than 5% has been explored. ? 10 10. Humans and all living things are inextricably connected to the ocean. In The Zone The Atmosphere—(an ocean of water, in the air): Intertidal Zone (In Epipelagic Zone) • Tufted Puffins can dive up to 196 feet (60 m) • Pigeon Guillemots can dive up to 212 feet (65m) Splash Zone organisms depend on sea spray for moisture, adapted Epipelagic Zone—To 650 feet (200 m) below the to long periods of surface—The sunlit upper layer of the ocean exposure • Moon Jellyfish • Barnacles • Many Sharks • Ribbed Limpets • Dolphins High Tide Zone Mesopelagic Zone—To 3300 feet (1000 m) organisms covered at most high tides below the surface—The twilight zone • Turban Snails • Swordfish • Chiton • Wolf Eel Mid Tide Zone • Ochre Sea Star • Green Anemone Bathypelagic Zone—To 13,000 feet Low Tide Zone (4,000 m) below the surface— most protection from The midnight zone (no sunlight) desiccation; inhabited by the most number • Anglerfish of species • Many Octopus • Dungeness Crab • Sea Hare Abyssopelagic Zone—To a known depth of 36,067ft or 6.831 mi (10, 993 m)—The abyss * The Abyssopelagic zone continues to yield its • Microbes secrets. In December 2014 a snailfish was found • * 5 miles (8 km) deep in the Mariana Trench! Page 2 Land and Water In Motion Land and Water Oceans and Climate The California Current Continental crust 15–45 miles (25-75 km) thick The Earth rotates from east to west The California Current flows south from Oceanic crust 4.5–6.3 miles (7-10 km) thick contributing to the circular movement of air latitude of British Columbia as part of the across the oceans. Relative to this rotation, North Pacific gyre. This river of water flows Our planet’s surface is divided into thin, the air is deflected to the right in the Northern along the coast from north to south and then stiff plates that move around on molten Hemisphere, and to the left in the Southern rotates east near Baja California. Additionally magma. If all of the plates were made of the Hemisphere, causing winds to develop. These during the spring months, easterly winds same material, and the surface of the earth global winds drag on the oceans’ surface blow from north to south-east across the was smooth, the oceans would cover the causing surface currents, and the currents coastal waters and the warmer surface waters earth to an average depth of 6500 ft. (2000 form ocean-circling spirals called gyres. are replaced by much colder water from m)! But there are two plate types: denser, the sunless depths. This process, known as thinner, balsalt oceanic rocks and lighter, The oceans strongly impact the world’s upwelling, is responsible for the very nutrient- thicker, granitic, continental rocks. If you climate. Energy from the sun is absorbed and rich waters off the California Coast. put a wooden block and a styrofoam block then circulated around the world in warm in a swimming pool, both would float, but surface currents. Since the cold waters are rich with nutrients the denser wood would float lower than the and more saturated with oxygen, they styrofoam. Similarly, the dense basalt sinks support a rich community of plankton (more deeper into the mantle, creating basins where Ocean Motion on page 4) , the basis of the marine food the water collects to form the great oceans of Water in the ocean is constantly moving. A chain. In general, the strongest upwelling the world. deep, global conveyor current underlies the happens between Point Conception and Cape surface currents. These are the thermohaline Mendocino. The largest seabird rookery Water evaporates from the ocean and currents. These currents are density driven, south of Alaska, the Farallon Islands, is falls over land as rain. As the ocean water resulting from differences in temperature situated in the middle of this area. evaporates, the minerals—mostly salt— and salinity. Dense, cold, salty water sinks remain behind in the sea. These ocean while warm, less salty water rises to the minerals originally came from rain water surface. The “start” of the ocean conveyor flowing over continental rocks, dissolving belt is in the northern polar regions. Cold minerals from those rocks, and flowing out arctic water sinks to the ocean bottom, and to sea. Deep in ocean trenches, there are is carried south, eventually flowing all the hydrothermal vents that also release minerals way to Antarctica! Over time this water Cape into the oceans. This is why ocean water is on warms up again, rises to the surface and Mendocino average seventy times more salty than fresh flows back north, where warm water currents g in water. ll Point carry water from the equator to the north, e w Reyes Because of the extra minerals, saltwater and heat is lost again to the atmosphere in p U Farallon the northern latitudes. This motion forms a t is denser than fresh water. When you see s Islands e globe-encircling oceanic conveyer belt. One t large rivers flowing out into the ocean, the a drop of water spends about 1000 years making e fresh water floats on top which causes color r G a round trip of over 25,000 miles! variations of the nearshore waters. f Point o Conception e n o Z Oyashio Ocean Waves Bering Alaska A wave is a disturbance that carries energy from one place to another. What we are North Pacific witnessing when we look at waves is the energy moving through the water, not the water moving horizontally any significant Kuroshio distance.