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[24-Feb-10] Other kinds of satellite sensors look at the Earth in a far different light. Heat sensing satellite instruments take the Earth's temperature by measuring infrared energy. Infrared wavelengths are invisible to our eyes, but some satellites can see them. And, as our climate changes, we can see ocean temperatures on the rise.
[26-Feb-13] Sea surface salinity measurements have come a long way, from shipboard sampling and autonomous floats to satellite scans. In this clip, Dr. Stephen Riser, Professor of Physical Oceanography at the University of Washington, discusses advancements in sea surface salinity research.
[05-Mar-13] In this clip, Dr. Raymond Schmitt, a Senior Scientist at the Woods Hole Oceanographic Institution, discusses the role that heat plays in warming the ocean and fueling the water cycle. He makes the case for a more globalized view of the water cycle, as the ocean plays a very large role in the process.
[22-Feb-10] This online activity challenges students to find the data set (e.g., air temperature, precipitation, evaporation) that most closely corresponds to ocean surface salinity patterns.
[18-Dec-10] Create monthly maps of global salinity, temperature or density at the surface or at specific ocean depths using this interactive data tool by NASA JPL.
[23-Feb-09] The Passive-Active L- and S-band (PALS) sensor in the C-130 aircraft that was used during flights over Monterey Bay, CA in 2000 and 2003.
[23-Feb-09] Front view of the prototype salinity instrument, PALS (Passive/Active L- and S-band radiometer).
[20-Feb-13] This visualization celebrates over a year of successful Aquarius observations. Sea surface salinity is shown at various locations around the globe.
[14-Sep-15] This visualization shows the complete observations of sea surface salinity taken during the life span of the Aquarius spacecraft.
[12-Feb-10] In this activity, students will investigate the idea that salt causes water to freeze at a lower temperature and that the oceans do not freeze (except in extreme polar areas) because of the salinity.
[25-Feb-10] Create global maps of mean salinity, temperature, or density for any year from 1800 to 2005 at designated depths using this data tool from NASA JPL.
[22-Feb-10] Interactive maps of average surface conditions can be clicked to create in-water profiles of salinity, temperature, or density. Options include mapping interpolated atlas data or individual data points from the database. Grade level: 5-8 or higher.
[15-Sep-18] The overall goal for this lesson is for students to learn more about the effect of ocean currents on climate change and determine if the possibility exists that rising atmosphere and ocean temperatures might trigger a meltdown of the Greenland Ice Sheet which could, in turn, stall the Great Ocean Conveyor Belt.
[24-Feb-10] The Earth's climate is changing ... in some places, faster than predicted. Something - or someone - is cranking up the heat. And many scientists say the main culprit is us.
[22-Feb-10] In this activity, students will use the weather section of the newspaper (or Internet) to help discover why coastal regions have relatively moderate climates.
[02-Jan-19] In this activity, students will determine how the amount of dissolved substances in solutions (i.e., concentration) is expressed and how concentration affects a solution.
[12-Aug-13] Learn about heat capacity in water (i.e. heat storage in water molecules) in this concept map, and how this enables life to be sustained on Earth. This interactive map also depicts how heat travels through the ocean (slowly) versus through the atmosphere (quickly).
[12-Aug-13] This interactive concept map shows how the water cycle is connected to Earth processes such as precipitation and evaporation and how these processes can affect global climate. The map also highlights ties between the Aquarius satellite instrument, salinity, and climate.
[12-Aug-13] This interactive concept map explains the structure of a water molecule and how changes in that structure create different states, or phases, of water: solid, gas, and liquid. The map also highlights the difference between sea ice and icebergs and what that means in terms of sea level and the "freshness" of ocean water.
[12-Aug-13] Learn about the differences between fresh and salty water in this interactive concept map, and how those difference affect water's temperature and density.
[05-Mar-13] Dr. Raymond Schmitt, a Senior Scientist at the Woods Hole Oceanographic Institution, talks about the effect climate change will have on the global water cycle and what that means for us.
[23-Apr-18] The major chemical constituents of seawater, displayed by quantity found in a kilogram of seawater.
[01-Dec-09] Convection and advection are the major modes of heat transfer in the ocean and atmosphere. Convection occurs only in fluids and involves vertical motion of fluid, or flow, rather than interactions at the molecular level. It results from differences in densities - hence buoyancy - of fluids. The purpose of this activity is to review the basic concepts of thermal physics and highlight applications to ocean processes by focusing on the concept of convection.
[23-Feb-10] In oceanography, density is used to characterize and follow water masses as a means to study ocean circulation. Plate tectonics and ocean basin formation, deep-water formation and thermohaline circulation, and carbon transport by particles sinking from surface waters to depth are a few examples of density-driven processes. This activity is designed to highlight links to oceanic processes.
[05-Apr-19] Most people think of salt water as a combination of sodium and chloride, but seawater has many more ingredients! In this clip, Dr. Stephen Riser, a Professor of Physical Oceanography at the University of Washington, explains what salinity is and how it is measured, and then summarizes the other ingredients of seawater.
[01-Mar-19] This activity investigates the effects of salinity and temperature on water density. Participants will fill small bags with water of different densities and float them in a tank of water, making predictions about their behavior.
[11-Feb-10] Dr. Susan Lozier (Professor of Ocean Sciences, Duke University): "I think most everybody can understand that if there is light fluid on top of heavy fluid then we have what's called a "stable system". Because things that are heavier are perfectly "happy" to be underneath something that's light."
[22-Feb-10] Two of the most important characteristics of ocean water are its temperature and salinity. Together they help govern the density of seawater, which is a major factor controlling the ocean's vertical movements and layered circulation. After completing this activity, students should be able to explain the effect of density on ocean circulation.
[12-Aug-18] This animation uses Earth science data from a variety of sensors on NASA Earth-observing satellites as well as cartoons to describe Earth's water cycle and the continuous movement of water on, above and below the surface of the Earth.
[25-Feb-10] Density is fundamentally important to large-scale ocean circulation. An increase in the density of surface water, through a decrease in temperature (cooling) or an increase in salinity (ice formation and evaporation), results in gravitational instability (i.e., dense water overlying less-dense water) and sinking of surface waters to depth. This experiment looks at the energy required to mix two layers.
[24-Feb-10] Stratification refers to the arrangement of water masses in layers according to their densities. This activity compares salt and fresh water, demonstrating that fluids arrange into layers according to their densities.
[24-Feb-10] Stratification refers to the arrangement of water masses in layers according to their densities. This activity compares warm and cold water, demonstrating that fluids arrange into layers according to their densities.
[28-Mar-14] In this activity, students will conduct an experiment to see that water can be split into its constituent ions through the process of electrolysis; prepare and experiment with a 10% salt solution to better understand the process of ion exchange; discuss and research the "softness" and "hardness" of water; and use the periodic table to identify elements and learn their characteristics.
[27-Apr-11] Evaporation is the process by which water changes from a liquid to a gas or vapor. Evaporation is the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor.
[12-Feb-10] Evaporation is the process by which water changes from a liquid to a gas or vapor. Evaporation is the primary pathway that water moves from the liquid state back into the water cycle as atmospheric water vapor. In this activity, students will investigate the idea that water can "disappear" into the air and will be able to explain that evaporation can separate the water from the salt in salt water.
[23-Feb-09] To track changes in sea surface salinity patterns over time, scientists monitor the relationship between two primary processes in the oceans: evaporation and precipitation. This map was produced by Gary Lagerloef, Principal Investigator for the NASA Aquarius satellite mission.
[02-Jun-14] In this video, Dr. Susan Lozier (Professor of Ocean Sciences, Duke University) explains how changes in ocean circulation are the result of not only changes in seawater density, but also the amount of wind blowing on the surface of the ocean to push the water around. This helps scientists explain more thoroughly the idea of the "global conveyor belt", a generalized term for the more aptly named "overturning circulation".
[02-May-17] Benjamin Franklin is known for shaping the Constitution, and experimenting with electricity. What doesn't often get mentioned is that he was also the first to chart the Gulf Stream. He completed the first scientific study of the current on this day in 1775, according to Today in Science History.
[08-Nov-13] Density is the mass per unit volume (mass/volume) of a substance. Salty waters are denser than fresh water at the same temperature. Both salt and temperature are important influences on density: density increases with increased salinity and decreases with increased temperature. This activity investigates how the density of an object and of the water affects whether the object will float or sink.
[23-Feb-10] A short list of salinity-related experiments that could be designed by students in middle grades.
[11-Feb-10] Dr. Susan Lozier (Professor of Ocean Sciences, Duke University): "Very salty parts of the world's ocean are the Mediterranean Sea and also the Red Sea. In fact, those areas are some of the saltiest places we know in the global ocean. The reason they are so salty is that there is such strong evaporation because they're so warm there and they have high winds. So those places are very salty."
[22-Feb-10] Dr. Susan Lozier (Professor of Ocean Sciences, Duke University): "Up until now when we've been trying to understand how density changes impact ocean circulation, we've really just had half the picture. Because we've just be able to look at our global coverage of temperature."
[05-Aug-13] This "Vital Signs of the Planet" website features key indicators, evidence, causes, effects, scientific consensus, and NASA's role in monitoring climate change.
[22-Feb-10] Gyres play an important role in redistributing heat from the low to middle and high latitudes, thus influencing air temperature, weather, and climate. After completing this investigation, students should be able to (1) demonstrate the influence of wind on ocean currents, and (2) describe the typical gyre circulation of surface currents in two major ocean basins.
[05-Aug-13] In this online game, students manage the density of seawater to make a submarine sink or rise in an effort to reach a treasure chest full of gold.
[22-Feb-10] Thermal physics is one of the science subjects that students are familiar with and experience on a daily basis, but intertwined with the experiential knowledge they bring to class comes a mixed bag of misconceptions that must be identified and addressed. The purpose of this activity is to review the basic concepts of thermal physics and highlight applications to ocean processes by focusing on the concept of latent heat.
[10-May-17] View changes in ocean temperature in recent years with this slideshow adapted from NASA and NOAA.
[26-Feb-13] Dr. Yi Chao, Project Scientist for the NASA Aquarius satellite mission, explains how satellite technology has evolved throughout the years to deal with the challenge of measuring ocean salinity from space.
[23-Feb-09] Sampling distribution of historical surface salinity measurements from ships, buoys, etc.
[23-Feb-09] HMS Challenger was a steam-assisted, Royal Navy Pearl-class corvette launched on 13 February 1858 at the Woolwich Dockyard on the river Thames. After serving as the flagship of the Australia Station, the ship was modified for scientific tasks and then used to conduct the first global marine research expedition (the Challenger Expedition).
[25-May-11] How does understanding salinity help us to better understand human-induced climate change? Dr. Gary Lagerloef, Principal Investigator for the Aquarius mission, explains in this video.
[01-Dec-96] In this 1996 overview article, Dr. Raymond Schmitt (Woods Hole Oceanographic Institution) summarizes fresh water's effect on ocean phenomena.
[24-Feb-10] Dr. Susan Lozier (Professor of Ocean Sciences, Duke University): "The salt in the ocean affects its density, just like the temperature affects its density. And the density, meaning the amount of mass per volume, is going to then impact how the ocean circulates, it's going to impact where the water goes as it circulates throughout the globe."
[29-Aug-19] The SPURS field campaigns utilized an extensive collection of in-water instruments and equipment to measure salinity, including ship-based, stationary, free-drifting, and mobile apparatus.
[14-Sep-15] Explore water in our earth system using this online version of the Earth Wheel activity, which showcases data from four current NASA missions.
[22-Feb-10] Water is a key element of the Earth's energy balance. The Sun's energy drives the water cycle, and in turn, water is a major factor in governing the surface temperature of the Earth. This activity covers multiple objectives related to energy in the climate system (e.g., defining albedo, explaining latent heat, determining the importance of energy absorption at Earth's surface, etc.)
[08-Oct-09] Carbon is all around us. This unique atom is the basic building block of life, and its compounds form solids, liquids, or gases.
[10-Jun-11] The United Launch Alliance Delta II rocket carrying the Aquarius/SAC-D spacecraft launched from NASA's Space Launch Complex 2 at Vandenberg Air Force Base on June 10, 2011, beginning a three-year mission to study our planet's salty seas.
[15-Jan-15] Launch, deploy and scan pattern of the SMAP satellite, rendered prior to its January 31, 2015 launch.
[12-Feb-10] When solutions of two different densities meet, the less dense solution will move on top of the more dense solution, resulting in a layering or stratification of solutions. Density is an important feature of seawater since many physical and biological processes are affected by it, such as moving heat around the globe (which influences climate and the feeding and reproduction of marine organisms). After completing this activity, students should be able to compare the basic properties of fresh and salt water (e.g., density, ability to dissolve salt, freezing point).
[28-Jan-14] Global ocean surface salinity composite map produced using Aquarius V2.0 data averaged over 2012. This map was produced by Norman Kuring, NASA GSFC.
[04-Jan-19] Instructions on how to make simulated seawater for experimental use.
[05-Dec-13] What kinds of science questions can we answer with ocean data collected from space? Watch this Spanish-language webinar as we go behind the scenes of this international mission and discover how Aquarius/SAC-D data can be used to map ocean and Earth processes - from the forest landscape of El Impenetrable and the habitat of an endangered dolphin species all the way to Antarctica!
[23-Aug-19] The concentration of dissolved salt in our ocean is known as salinity. Since 2011, data from NASA satellites have unveiled changing salinity patterns. But to get a simple measurement like salinity, you need to untangle a lot of complicated signals.
[13-Oct-09] A lot of people live in coastal areas. Coastal places that have beaches. As sea level rises, then beaches begin to erode and we begin to lose wetlands.
[13-Oct-09] The ice is melting. The seas are rising. Little by little, in most parts of the world, the ocean is overtaking the land.
[13-Oct-09] Two thirds of the fresh water on Earth is frozen in the world's ice fields. If that ice melts, seas will rise. If all of that ice were to melt, sea level would rise worldwide by 70 meters.
[13-Oct-09] It's important to understand how the world's ice sheets form, how they change over time, and how fast they are moving into the sea. That's where researchers like NASA's Lora Koenig come in.
[24-Feb-10] Soon a new satellite will even help us see tiny particles on the ocean's surface - like salt, which drives huge conveyor belts of water through the world's oceans, connecting currents and moving heat from pole to pole. Climate change could mean big changes for oceans. And that in turn would make life very different for those of us on dry land.
[28-Aug-13] In June 2014, Aquarius salinity imagery on the NASA Earth Observations (NEO) website was updated to use Version 3 processing, including implementation of the smoothed version for the monthly products. On NEO, you can browse and download imagery of satellite data from NASA's constellation of Earth Observing System satellites.
[24-Feb-10] Students will chart the temperatures of two cities at approximately the same latitude but on different sides of North America. They will develop a hypothesis that explains the temperature differences between the two cities and create an air temperature model to test their hypothesis. They will measure the air temperature near a "cold water" current and a "warm water" current.
[16-Nov-17] This visualization shows ocean currents in the Northern Atlantic from Jan 01, 2010 to Dec 31, 2012. Compare the sea surface currents (0 meters) with the deep ocean curents (2000 meters).
[22-Feb-10] This data visualizer on NASA's Ocean Motion website gives access to the following global ocean surface current behaviors between 1992 and 2014: current speed, current direction, current convergence, and current vorticity as well as the anomaly values for each.
[22-Feb-10] This data visualizer on NASA's Ocean Motion website includes wind speeds and directions from 1999 to 2009.
[19-Feb-10] Dr. Susan Lozier (Professor of Ocean Sciences, Duke University): "One of the concerns we've had is whether or not the salinity changes will impact what's called the very large-scale ocean overturning circulation, what many people refer to as the global ocean conveyer belt."
[10-Sep-13] Learn about ocean salinity from an entirely different perspective! While Aquarius is measuring ocean salinty from above, a team of NASA researchers has been investigating the ins and outs of salinity - from the ocean's surface to depth - in one of the saltiest places of the ocean.
[03-Jan-19] In this activity, students break down the constituents of sea water (hydrogen, oxygen, major elements, minor elements and trace elements) into parts per thousand.
[29-Mar-12] This visualization, based on ocean temperature, salinity, sea surface height and sea ice data collected during field observations and by NASA satellites between July 2005 and December 2007, highlights many of the world's most important ocean surface currents.
[28-Mar-14] Seawater contains many dissolved substances and these add mass to the water producing a greater mass per unit volume, or density, than that of pure water. The relationship between the density of a fluid, weight of an object, and buoyancy is critical in understanding the ocean, because density has a direct influence on the way seawater and objects in seawater behave.
[06-Mar-14] Earth's water is stored in ice and snow, lakes and rivers, the atmosphere and the oceans. How much do you know about how water is cycled around our planet and the crucial role it plays in our climate? Take this quiz from NASA's Climate Change Vital Signs of the Planet website and find out!
[12-Feb-10] In this activity students will investigate water's unique properties, including the differences between fresh water and seawater.
[05-Aug-13] How much do you know about Aquarius? Find out here!
[04-Aug-14] How much do you know about Aquarius? Take version 2 of our popular quiz and find out!
[24-Sep-13] Technological advancements in oceanographic data collection, both from autonomous floats and gliders to satellites have allowed scientists to gain a better understanding of how key ocean processes work and impact things like ocean circulation, the water cycle, and global climate. Dr. Stephen Riser, a Professor of Physical Oceanography at the University of Washington, explains the importance of this technology and why a rain event over the ocean can tell us a lot about how the ocean moves water from place to place.
[01-Jan-19] In this activity, heat is used to evaporate seawater in steps, revealing salt crystals that are left behind. Students will seperate the substances in the seawater and answer questions about the process and results.
[24-Feb-10] Dr. Susan Lozier (Professor of Ocean Sciences, Duke University): "When these waters at very high latitudes - (your) Greenland, Iceland - when they sink in the wintertime (it's) because they are very dense. Those waters sink, they spread to the global ocean and (eventually) they need to return. When they return, they are returning in the surface waters. That's why it's referred to as an overturning."
[07-Aug-13] The 50-year, linear trend in global surface salinity in Practical Salinity Units (PSU; roughly equivalent to parts per thousand).
[23-Oct-19] Crystals of fine salt, imaged at 150x in a FIB-SEM (Focused Ion Beam Scanning Electron Microscope).
[13-Oct-09] People have been measuring salinity for centuries, but ships and buoys alone cannot match the perspective from space. In fact, a whole quarter of the oceans have no salinity data at all.
[13-Oct-09] The atmosphere and the ocean, both being fluids of the earth, really work together. We consider them equal partners in the redistribution of this heat on the planet.
[13-Oct-09] Dr. Susan Lozier (Professor of Ocean Sciences, Duke University): "Salt is really a molecule in the ocean water, but collectively, that salinity plays a role in ocean circulation."
[05-Aug-13] Test your knowledge of ocean salinity and its relation to climate change and ocean circulation in this online quiz from NASA's Global Climate Change website.
[04-Nov-15] NASA's Spacecraft 3D is an augmented reality (AR) application that lets you learn about and interact with a variety of spacecraft that are used to explore our solar system, study Earth, and observe the universe.
[06-Oct-09] Carbon is the basic building block of life, and these unique atoms are found everywhere on Earth. Carbon makes up Earth's plants and animals, and is also stored in the ocean, the atmosphere, and the crust of the planet. A carbon atom could spend millions of years moving through Earth in a complex cycle. This conceptual animation provides an illustration of the various parts of the carbon cycle.
[26-Feb-13] In this clip, Dr. Eric Lindstrom, a Program Scientist at NASA Headquarters, talks about the connection between ocean-going vessels and ocean-observing satellites and how both are vital in learning more about how ocean circulation works and affects our planet.
[27-Mar-14] Chemically, table salt consists of two elements, sodium (Na) and chloride (Cl). Neither element occurs separately and free in nature, but are found bound together as the compound sodium chloride. Seawater contains an average of 2.6% (by weight) sodium chloride, or 78 million metric tons per cubic kilometer, an inexhaustible supply. After completing this activity, students will be able to explain the general relationship between an element's Periodic Table Group Number and its tendency to gain or lose electron(s); explain the difference between molecular compounds and ionic compounds; use a model to demonstrate sodium chloride's cubic form which results from its microscopic crystal lattice; and describe the nature of the electrostatic attraction of the oppositely charged ions that holds the structure of salt together.
[11-May-19] Students explore how unequal heating of Earth's surface by the sun drives global ocean circulation patterns in this media-rich lesson plan from WGBH.
[25-Mar-16] The ocean is essential to life on Earth. Most of Earth's water is stored in the ocean. Although 40 percent of Earth's population lives within, or near coastal regions, the ocean impacts people everywhere. Without the ocean, our planet would be uninhabitable. This animation helps to convey the importance of Earth's oceanic processes as one component of Earth's interrelated systems.
[05-Mar-13] The patterns of evaporation and precipitation can tell us a lot about the state of the Earth's water cycle. In this clip, Dr. Raymond Schmitt, a Physical Oceanographer at the Woods Hole Oceanographic Institution, illustrates the overall patterns by comparing precipitation and evaporation over time across the globe.
[10-May-11] Measurements of sea surface salinity, or the concentration of salt at the ocean's surface, give scientists vital information on global ocean circulation and how freshwater moves between the ocean and other reservoirs.
[12-Feb-10] Water can change states among liquid, vapor (gas), and ice (solid) at various stages of the water cycle. Temperature affects the change of water from one state to another. When water vapor gets cold it changes to a liquid. This is called condensation. When heat is applied to water, it changes from a liquid to a gas. This is called evaporation. This activity focuses specifically on two aspects of the water cycle: evaporation and condensation.
[22-Feb-10] In this hands-on activity students will review the basic concepts of thermal physics and highlight applications to ocean processes by focusing on the concept of thermal expansion.
[08-Oct-09] Surface ocean currents are driven mostly by the wind. In certain areas near the polar oceans, the colder surface water also gets saltier due to evaporation or sea ice formation. In these regions, the surface water becomes dense enough to sink to the ocean depths.
[14-Nov-11] The oceans are mostly composed of warm salty water near the surface over cold, less salty water in the ocean depths. These two regions don't mix except in certain special areas.
[24-Feb-10] The Earth's climate is changing... in some places, faster than predicted. Something - or someone - is cranking up the heat. And many scientists say the main culprit is us. Climate change affects almost everything on our planet - including people. But could climate change affect something as huge, as deep, as mysterious as our oceans? Earth scientists are determined to find out.
[05-Mar-13] The water cycle plays an important role in distributing heat and energy around the globe. Dr. Raymond Schmitt, a Senior Scientist at the Woods Hole Oceanographic Institution, expands on the traditional view of this cycle, emphasizing the dominance of the ocean.
[23-Feb-09] The cycling of water and energy through the atmosphere and oceans is crucial to life on Earth. Yet the ties among the water cycle, ocean circulation, and climate are poorly understood. Interestingly, global measurement of ocean surface salinity over time provides a clear way resolve these relationships.
[23-Feb-09] Sea surface salinity is a key tracer for understanding how fresh water cycles in and out of the ocean. Some processes in the global water cycle increase salinity, while other processes decrease it.
[07-Aug-13] The U.S. Geological Survey and the Food and Agriculture Organization of the United Nations teamed up to create a water-cycle diagram for kids in elementary and middle schools.
[09-Oct-09] In this video clip NASA program manager Paula Bontempi narrates the processes of condensation and precipitation in the water cycle, on both a molecular and global scale, using animations and satellite imagery.
[09-Oct-09] Water is all around us, and its importance to nearly every process on earth cannot be underestimated. It is the only compound that can be found naturally as a liquid, gas, and solid. The process by which water moves around the Earth, from the ocean to the atmosphere to the land, and back to the ocean, is called the water cycle.
[09-Oct-09] The water cycle affects and is affected by climate variations. The water cycle is one of the ways that we will really feel any changes in climate.
[26-Feb-13] By using maps depicting ocean color - which tell us something about the plants growing in the ocean - Dr. Eric Lindstrom, a Program Scientist at NASA Headquarters, is able to explain how and why seasonal changes in plant life at sea take place.
[15-July-18] In all, the Earth's water content is about 1.39 billion cubic kilometers (331 million cubic miles), with the bulk of it, about 96.5%, being in the global oceans. As for the rest, approximately 1.7% is stored in the polar icecaps, glaciers, and permanent snow, and another 1.7% is stored in groundwater, lakes, rivers, streams, and soil. Only a thousandth of 1% of the water on Earth exists as water vapor in the atmosphere.
[02-Jun-14] What does it mean to have a "salty" ocean and why does it matter if salinity varies from place to place? In this clip, Dr. Stephen Riser, a Professor of Physical Oceanography at the University of Washington, explains to viewers that ocean salinity is a mirror to the global water cycle. Salinity also plays a role in determining seawater density, which can determine where water travels throughout the oceans.