Paul Watson
Critical temperature is the temperature above which a gas cannot be liquified; no matter how great is the pressure that is applied. Critical temperature is the temperature of the melting point of liquid vapour, that is, the temperature at which it is difficult to liquefy a gas by rising heat. At a critical point, which is determined by both critical temperature and critical pressure, there will be no liquefaction to increase the pressure and no gas will be produced to increase the temperature. It’s this given regime that is the supercritical area by name.
Tropical deforestation is causing public fear. There is evidence to show that it is influencing global warming. Furthermore, ecological diversity is endangered because tropical forests host half of the world’s plant and animal populations, and occupy less than 10 percent of the Earth’s land surface. What is deforestation? Deforestation is not a phenomenon that merely occurs and then stops indefinitely. Deforestation is in effect a constant mechanism of human activity, stopping the forest from rising again, as it would be if it were actually left alone.
Critical Temperature Explanation
The critical temperature for steam is about 365oC and the corresponding pressure is about 2950 pounds per square inch. In the action of an ordinary steam engine the critical point is never approached. But with carbonic acid, whose critical temperature is only about 31oC, the behaviour in the neighbourhood of the critical point, and above it is of great practical importance in connection with refrigerating machines which employ carbonic acid as working substance.
Gases such as air, hydrogen, oxygen and so forth are vapours which under ordinary conditions are very highly superheated. Their critical temperatures are so low that it is only by extreme cooling that they can be brought into a condition which makes liquefaction possible. What is the critical temperature of hydrogen? The critical temperature of hydrogen is -241oC or 32o absolute. Even helium, the most refractory of gases, has been liquified, but only by cooling it to a temperature within about 5 degrees of the absolute zero.
The Impact of Deforestation
Deforestation can dramatically change landscapes in a short time. However, the effects of deforestation may last for years. The changes in landscape range from local loss of biodiversity to large scale effects on ecosystems and the atmosphere. The effects of deforestation range from the global to the local level. It is almost unfeasible to calculate the consequences of humankind’s diminution over the forests.
For many animals the forest is their natural habitat. When trees are cut down this reduces the space, food, and other resources available to the wild animals who live in forest biomes. The danger of species becoming extinct, or completely wiped out, is especially high in the species rich tropical forest biome. For example, most parrots live in tropical forests, feed on forest fruits and nest in holes in trees. Without trees, they cannot survive. Deforestation is a major reason why almost a third of parrot species worldwide are endangered.
