Carbon dioxide, chemical formula CO2, accounts for 0.03-0.04% of the volume in the air. The relative molecular mass is 44, commonly known as carbon dioxide gas, also known as carbonic anhydride or carbonic anhydride. It is a colorless, odorless gas at room temperature, slightly denser than air, and slightly soluble in water.

Air contains carbon dioxide. After dissolving in water, it becomes carbonated beverages and appears in beer and carbonated beverages. Solid carbon dioxide is called "dry ice", which can be directly sublimated into gaseous carbon dioxide from the solid state, lingering on the stage with the effect of clouds and mountains. Dry ice fire extinguishers can also be seen in our daily life. In addition, the production of ammonium bicarbonate, a chemical fertilizer that is relatively easy to use in agricultural production, also requires carbon dioxide.

Carbon dioxide can be seen everywhere in our life, and there are many uses.

However, with the expansion of the scope of human activities and the rapid development of industry after the Industrial Revolution, there are many factories and mines on the earth, various means of transportation have increased sharply, and carbon dioxide emissions have increased day by day. Coupled with the deforestation, the absorption and solidification of carbon dioxide has been reduced, and the carbon dioxide in the atmosphere has accumulated more and more, and various environmental problems caused by it have made humans have to pay attention to the problem of "CO2".

1. "Earth Warming"

The atmosphere can enable the sun's short-wave radiation to reach the ground, but the long-wave thermal radiation emitted by the ground will be partially absorbed by the atmosphere, and carbon dioxide is one of the greenhouse gases. Therefore, if the carbon dioxide content of the earth's atmosphere is higher, the more long-wave thermal radiation will be absorbed, and the ground has been absorbing the sun's short-wave radiation. For the earth as a whole, it absorbs more and more heat energy but cannot "dissipate heat", so that There is only one result: the earth is "heated"!

From 1860 to 1986, carbon dioxide in the atmosphere increased at a rate of 26%. If it is not restrained, the carbon dioxide in the atmosphere will reach 500ppm by the middle of this century, and the global temperature will rise by 4°C.

The greenhouse effect increases the temperature of the earth, melting glaciers in the Arctic and Antarctic, and rising sea levels. This led to a series of natural disasters that human beings could not bear. In recent years, the catastrophic consequences of global warming have been visible to the naked eye. Floods and droughts, storms, ice and snow, and extremely cold and hot weather have frequently occurred around the world.

1. Extreme weather that has not been seen in China for decades occurs frequently: the snow disaster in the south of 2008. In 2012, the heavy rain that Beijing has not encountered in 61 years. The super typhoon "Mangosteen" in 2018. Heavy rain in Henan in 2021, etc.

2. International extreme weather: In 2021, parts of southwestern Japan will experience the heaviest torrential rain in decades. In July 2021, a high temperature of 48°C will appear in the Arctic. On July 29, 2021, many places in Brazil ushered in rare snowfall. On June 29, 2021, Lytton in western Canada broke Canada's record high temperature record for three consecutive days.

The extreme weather around the world takes turns, each time causing huge damage to the human living environment, resulting in huge economic losses. If human industrial activities are not restricted, the earth will be heated all the time, and human beings will eventually be greeted with catastrophe.

2. Seawater acidification

The ocean provides us with abundant biological resources, and by absorbing a large amount of carbon dioxide in the atmosphere, it has slowed down the rising trend of carbon dioxide in the atmosphere. However, as the total amount of carbon dioxide in the atmosphere continues to increase, carbon dioxide continues to dissolve in the seawater, which eventually reduces the pH of the seawater. Studies have shown that the pH value of the ocean has dropped by an average of 0.075 from 1751 to 1994, which may be a threat to the survival of marine organisms such as crustaceans and invertebrates. Ocean is the source of gas for life on earth. Ocean acidification is another environmental problem caused by greenhouse gases. Seawater acidification may not only cause changes in the chemical composition of seawater, but also change the biological chain of marine ecosystems, and even affect the global climate.

Fortunately, humans are fully aware of these hazards and are taking action, so carbon dioxide emissions reduction, carbon peaking, carbon neutrality and other terms related to carbon dioxide frequently appear before our eyes.