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Normally a gas, (colourless and odourless) that consists of two oxygen and one carbon atom, has the formula CO2. It is a ‘greenhouse gas’ that easily dissolves in water and is used to give the bubbles in fizzy drinks.
A demonstration of buoyancy. It shows a small ‘diver’ going up and down because of a change in water pressure.
Organisms in a food chain that ‘consume’ energy. They include herbivores (that eat plants) and carnivores (that eat other animals). Worms, zooplankton, dogs and penguins are all carnivores.
A CTD is an instrument lowered over the side of a ship to measure electrical conductivity, temperature, and depth of the ocean. The CTD often has a number of steel sampling bottles connected to a round frame called a carousel or rosette. The sampling bottles close at predefined depths, triggered either manually or by a computer. The water samples are analysed later. A CTD is used to calibrate Argo Floats.
The 10 day period of movement of an Argo Float: from the sea surface down to 1,000m for 9 days then down to 2,000m then up to the suface to upload its data ( = a profile).
Deep Argo Floats
Argo floats designed to go down to depths of 5,500m. They are spherical in shape to withstand the high pressures at this depth.
The amount of mass in something. To find the density of something you divide its mass by its volume density = mass/volume = kg/m3 or g/cc (grams divided by cubic centimetre).
A place where seawater, because it is heavier eg saltier and/or colder, sinks to the bottom causing an ocean current
An imaginary line around the middle of the earth. It is given the latitude number of zero degrees (0°).
A push or a pull that causes something to move or change shape (the force of gravity caused the ball to fall to the earth). The unit of force is the newton. One newton (N) will accelerate 1 kilogram of mass at the rate of 1 metre per second per second.
Imaginary lines around the earth parallel to the equator. Latitude is used together with longitude to specify the precise location of features on the surface of the Earth. The New Zealand mainland sits between latitudes 34° and 46° south.
Imaginary lines around the earth that go through the north and south poles. LInes of longitude are not parallel. Longitude is used together with latitude to specify the precise location of features on the surface of the Earth. The New Zealand mainland sits between longitude 166° and 179° east.
Is the amount of stuff in something. Measured in kilograms. You need to know the mass of something to find its density (density = mass/volume = kg/m3)
When an object stays at the same position. It doesn’t sink or rise. The density of the object is the same as the density of the fluid it is in.
Stands for the National Institute of Water and Atmospheric Research. It is a Crown Research Institute of New Zealand specialising in environmental sciences eg aquaculture, aquatic biodiversity, aquatic biosecurity, atmospheric science, climate change, coastal ecology, energy, fisheries, hydrology, marine geology, natural hazards (e.g. tsunami, storm surge, floods, earthquake, volcano), oceanography, sedimentology.
Stands for the National Oceanic and Atmospheric Administration and is a scientific agency within the United States Department of Commerce focused on the conditions of the oceans and the atmosphere.
Means ‘open sea’. Any area of water away from land. The pelagic zone can be thought of as an imaginary cylinder or water column that goes from the surface to the bottom. Conditions change deeper down the water column: the pressure increases, the temperature drops and there is less light.
A chemical process that produces food in plants. During photosynthesis, carbon dioxide and water are combined using sunlight (photo = light, synthesis = to make).
The force applied to a surface area. Pressure = force/area = newton/m2. Pressure is measured in pascals. 1Pa = 1kg/1m2
The plants at the start of every food chain. Producers ‘produce’ food by combining water and carbon dioxide and sunlight. Grass, oak trees, phytoplankton and corn plants are producers.
A diagram showing changing temperature and salinity as the Argo Float rises to the surface. Every 10 days the Argo Float surfaces and sends data to a satellite. The data describes a profile. There have been over a million separate Argo Float profiles uploaded since the first Argo Float was deployed in the year 2000.
The amount of dissolved salt in water. Seawater usually has 35g of salt per 35kg of water =3.5%. Salinity is often measured by seeing how easily water conducts electricity
In chemistry the word salt has a special meaning. Most people think of salt as table salt which is a mineral substance made up of sodium (Na) and chlorine (Cl). Table salt or sodium choride has the chemical formula NaCl. Seawater is salty because of the large amounts of sodium chloride in the water. There are 35grams of sodium chloride in every litre of sea water.
Frozen seawater. Because ice is less dense than water, it floats on the ocean's surface. The ice that forms when seawater freezes in winter in the Arctic and Antarctic takes up 7% of the world’s surface and 12% of the world’s oceans. When seawater freezes, salt is squeezed out and collects in the water below the sea ice. This adds to the density of the water which sinks, to be replaced by warmer water from the surface. This creates a ‘conveyor belt’ motion of ocean currents.
Dissolves in water (sugar is soluble in water)
A place where deep water rises to the surface and pushes the surface water away. The rising water is usually rich in nutrients and oxygen and stimulates the growth of producers mainly phytoplankton.
Microscopic animals that feed on phytoplankton (zoo = animals, plankton = wanderer).