Earth is 75% covered with water, so it is likely that an asteroid will hit an ocean at some point in time. A shocking but true fact is that the deepest point in an ocean bed is the Mariana Trench, and that is just 11 km deep. And, to just let you know, the impact speed of an asteroid is around 30 kilometers per second. Astronomers have apparently discovered that 400 asteroids are present in the orbit of the earth and pose as a prime candidate in being a potential threat to earth in the distant future. Let’s see what will actually take place if an asteroid were to hit the oceans.
Yes! The most likely occurrence is a Tsunami. The amount of water present in the ocean would not be able to cushion the asteroid, but let all the water overflow and cross the limits. The impact of the asteroid will be so large that it will push all the water aside and will possibly hit the ocean floor to create large tidal waves resulting in a tsunami. The crustal shifting in the ocean will end up producing more tsunamis. A tsunami can be about 300 feet high and may travel till 20 kilometers, putting 100 million people at risk. A strike like this is expected once in every 300,000 years or so.
The material that gets ejected from the asteroid will enter all over the globe and because of the friction it will heat up the atmosphere. The lumps of material will be scorching enough to generate a lot of infrared light. This heat will eventually start fires around the globe, resulting in 7 × 1010 tons of soot into the air. Eventually, all this will put great stress on the environment.
The moment the asteroid enters, heat from the shock waves will get generated and result in the reprocessing of the air. Sooner or later, it will start producing nitric and nitrous acids in the following months.
The chemical reaction chain will be disrupted-
N2 + O2 ‚> NO (molecular nitrogen if combined with molecular oxygen will produce nitrogen monoxide)
2NO + O2 ‚> 2NO2 (two nitrogen monoxide molecules combined with one oxygen molecule will produce two nitrogen dioxide molecules)
NO2 will be converted to nitric and nitrous acids when it will get mixed with water.
This will further attribute in massive amounts of weathering of rocks. The organisms present in the ocean will evidently get killed. The upper ocean organisms which are responsible for locking up CO2 in their shells will possibly get dissolved in the acid water. 90% of all the marine Nano-
Plankton species (plants that are responsible for making free oxygen from photosynthesis) will be brutally killed.
Ozone Layer Depletion
If an asteroid measuring 1 km will strike an area over 1000 km in diameter, massive amount of water and vapor are likely to get expelled up to 160 km high. The vapor would contain a great amount of bromine and chlorine. This will result in a significant destruction of the ozone layer faster than it would be created naturally. This will produce a huge spike in the levels of ultraviolet radiation. This will ultimately increase the rates of skin cancers and cataracts. People will have to remain indoors to avoid rapid sunburns.
Similar incident had occurred in Antarctica during the 1990’s. UV Index’s Daily Forecasts Studies show that the UV levels had soared beyond the measurements done so far on Earth.
The asteroid hit will cause a drastic short-term global reduction in the temperature which is scientifically known as impact winter. There are all the chances that plant photosynthesis will stop and also lead to a decline in the food chain. The drop in temperature will be followed by a large increase in the greenhouse effect due to increased carbon dioxide and water vapor presence in the air.
An oceanic impact of an asteroid will have its effect all over the world. It will take months and years for the displaced water to drain back into its original place. This impact can also change the shape of the coastlines and continents too.