Emphysema destroys alveoli, which are air sacs in the lungs. The air sacs weaken and eventually break, which reduces the surface area of the lungs and the amount of oxygen that can reach the bloodstream. This makes it harder to breathe, especially when exercising. Emphysema also causes lungs to lose their elasticity. Emphysema is one of the two most common conditions that fall under the umbrella term chronic obstructive pulmonary disease (COPD). The other major COPD condition is chronic bronchitis. Emphysema is an irreversible condition, so treatment aims to slow its progression and minimize symptoms.
Ocean water, with an average salinity of 35 psu, freezes at -1.94 degrees Celsius (28.5 degrees Fahrenheit). That means at high latitudes sea ice can form. The average temperature of the ocean surface waters is about 17 degrees Celsius (62.6 degrees Fahrenheit).90 % of the total volume of ocean is found below the thermocline in the deep ocean. The deep ocean is not well mixed. The deep ocean is made up of horizontal layers of equal density.he average temperature of the ocean surface waters is about 17 degrees Celsius (62.6 degrees Fahrenheit). 90 % of the total volume of ocean is found below the thermocline in the deep ocean.
The thermocline is the transition layer between the mixed layer at the surface and the deep water layer. The definitions of these layers are based on temperature.The mixed layer is near the surface where the temperature is roughly that of surface water.In the thermocline, the temperature decreases rapidly from the mixed layer temperature to the much colder deep water temperature.The mixed layer and the deep water layer are relatively uniform in temperature, while the thermocline represents the transition zone between the two.he mixed layer is near the surface where the temperature is roughly that of surface water. In the thermocline, the temperature decreases rapidly from the mixed layer temperature to the much colder deep water temperature.