In most parts of the Antarctic and Arctic, the temperature rarely rises above 0 ℃. The frozen landscape there is made up of different types of ice. When the snow falls on the land, it piles up, and the snow grains are squeezed to form glacier ice. Huge glacial ice forms the ice sheet, covering most of Antarctica and Greenland. These ice sheets are usually more than 2.5 kilometers thick, accumulating most of the earth's fresh water resources. In polar regions it is extremely cold; in such regions, the surface of the ocean freezes, which is called sea ice. Most of the water and the coast of Antarctica are covered with sea ice.
The Qinghai Tibet Plateau is the largest plateau in China and the highest altitude in the world, known as the 'roof of the world' and 'the third pole'. The Qinghai Tibet Plateau is about 2800km long from east to west, about 300-1500km wide from north to south, with a total area of about 2.5 million square kilometers. On the topography, it can be divided into six parts, including the North Tibet Plateau, the South Tibet Valley, the Qaidam Basin, the Qilian Mountains, the Qinghai Plateau and the Sichuan Tibet high mountain canyon area Tibet, China, Qinghai, Xinjiang, Gansu, Sichuan, Yunnan and Bhutan, Nepal, India, Pakistan, Afghanistan, Tajikistan, Kyrgyzstan.
The atmosphere is the air that surrounds the earth. But the weather, speaking from the phenomenon, is mostly the result of the moisture change in the atmosphere. Under the joint action of solar radiation, underlying surface forcing and atmospheric circulation, the long-term comprehensive situation of weather formed is called climate. The impact of air pollution on the physical state of the atmosphere is mainly caused by abnormal changes in the climate.
Desert mainly refers to the barren area where the ground is completely covered by sand, plants are very rare, rainwater is scarce, and air is dry. Desert is also known as 'sand curtain'. It is a dry and water deficient area with few plants. Desert areas are mostly sand beaches or sand dunes, and rocks under the sand often appear. Some deserts are salt flats, completely devoid of vegetation. Deserts are generally aeolian landforms. There are precious deposits in the desert sometimes, and a lot of oil reserves have been found in modern times.
Debris flow refers to the special torrent which is caused by rainstorm, Blizzard or other natural disasters and carries a large amount of sediment and stones in mountainous areas or other ravines and steep terrain areas. Debris flow has the characteristics of abruptness, high velocity, large discharge, large material capacity and strong destructive power. Debris flow often destroys traffic facilities such as roads and railways, even villages and towns, causing huge losses.
Landslide refers to the natural phenomenon that the soil or rock mass on the slope slides down the slope as a whole or dispersedly along a certain weak surface or zone under the influence of gravity due to river erosion, groundwater activity, rainwater immersion, earthquake, artificial slope cutting and other factors. The moving rock (soil) body is called displacement body or sliding body, and the immobile underlying rock (soil) body is called sliding bed.
