March 29, 2011:
In what has become an annual event, the Chinese government has ordered the army and air force to try and prevent flooding on the Yellow river, near the Mongolian border, by using bombs and shells to break up the temporary ice dams that sometimes form near there, and cause Spring melt water to back up and flood towns and farms along the river. The 5,500 kilometer long river, the second longest in China, has this ice dam problem in 800 kilometers of the river that flows through chilly Inner Mongolia (the Chinese province, which is next to Mongolia the country). This year, the air force sent three H-6 bombers on March 22nd, which dropped 24 half-ton bombs. This was to break up an ice dam nearly three kilometers wide and up to 500 meters thick. On some years, 152mm artillery is also used.
Using bombers and artillery is a long shot, as the ice dams are often quite sturdy. But the warplanes have been doing this for over half a century, and found that the explosions do bust up quite a lot of ice, especially the half ton bombs. The 152mm artillery shells (weighing about 41 kg/90 pounds each) are less effective, but the army has a lot of older ammo it doesn't mind firing before the stuff becomes too old and unstable. One thing the army and air force have to take careful note of are bombs and shells that don't go off. That leaves potentially dangerous duds at the bottom of the river, ready to endanger future dredging or bridge construction projects.
Alas, sometimes all this is a public relations exercise. If you wanted to use explosives to break up ice jams, it is often easier, cheaper, and more effective, to just move explosives by truck and helicopter to the river. The military could do this, but it does not have the PR impact of falling bombs and booming artillery. However, in many cases, the ice dams are too unstable and dangerous for engineers to place the explosives. Besides, the army and air force have lots of older munitions that will have to be retired (they become unstable as they age), and the bombing and shooting provide some good practice for the troops.
Russia pioneered the use of aerial bombing to break up these Springtime ice dams, and the Chinese learned from that.