41. what is upwelling in the ocean? 42. what is brought to the surface as a result of upwelling? 43. what does brackish mean? 44. what bodies of water would be brackish? 45. what type of technology is primarily used to map the ocean floor? 46. how would the ocean be affected if there were no estuaries? 47. what is a hydrothermal vent? 48. describe the intertidal zone of the ocean? 49. what special conditions do organisms that live in the intertidal zone encounter? 50. describe the oceanic zone.

41.) A process in which deep, cold water, rises toward the surface
42.) Surface waters are replaced by cold, nutrient-rich water that “wells up” from below.
43.) Slightly salty, as is the mixture of river water and seawater in estuaries.
44.) Brackish water condition commonly occurs when fresh water meets seawater. In fact, the most extensive brackish water habitats worldwide are estuaries, where a river meets the sea.
45.) Sonar. Echo sounding is the key method scientists use to map the seafloor today.
46.) I'm not sure, I don't want to give you the wrong answer. Sorry.
47.) An opening in the sea floor out of which heated mineral-rich water flows.
48.) Also known as the foreshore and seashore maybe referred to as the littoral zone. This is the area that is above water at low tide and under water at high tide (otherwise, the area between tide marks).
49.) A harsh and unforgiving habitat, subject to the rigors of both the sea and the land.
50.) Typically defined as the area of the ocean lying beyond the continental shelf, but operationally is often referred to as beginning where the water depths drop to below 200 meters (656 feet), seaward from the coast to the open ocean.