Scientists have observed global warming and consider that the process results when the atmosphere traps heat radiating from Earth toward space.The existing gases in the atmosphere prevent the heat from escaping by blocking it. The remaining long-lived gases stay semi-permanently in the atmosphere and are not physically or chemically influenced as a result of climate change. The gases, which respond physically or chemically to changes in temperature, are seen as “feedbacks”. Such gases are water vapor,carbon dioxide, methane, nitrous oxide, Chlorofluorocarbons (CFCs),etc.
• Water vapor
When the Earth’s atmosphere warms, water vapor strongly increases. Clouds and precipitation can cause it as well. They make the water vapor one of the most important feedback mechanisms to the greenhouse effect.
• Carbon dioxide (CO2 )
Another important but tiny component of the atmosphere is carbon dioxide emitted during various natural processes such as respiration and volcano eruptions. Human activities such as deforestation, land-use changes, and burning fossil fuels are also able to increase carbon dioxide in the atmosphere. As a result of such actions the atmospheric CO2 concentration has increased by 48% since the Industrial Revolution. Carbon dioxide is the most important long-lived forcing of climate change.
It is produced both through natural sources and human activities. Such activities include the decomposition of wastes, as well as ruminant digestion and manure management. Methane isn’t as active a greenhouse gas as carbon dioxide, but its number in the atmosphere doesn’t proceed with carbon dioxide.
• Nitrous oxide
This greenhouse gas is produced by soil cultivation practices, especially by using commercial and organic fertilizers, fossil fuel combustion, nitric acid production, and biomass burning. On the planet Earth, human activities can cause changes to the natural greenhouse. Over the last century, burning fossil fuels like coal and oil have increased the concentration of atmospheric carbon dioxide (CO2 ). It is produced when the coal or oil burning process combines carbon with oxygen in the air to make CO2. It is difficult to predict the consequences of the changes in the natural atmospheric greenhouse, but some effects are certain.
• The Earth’s becoming a warmer place
But this change doesn’t refer to the whole world. Some regions may come across warmer temperatures, while others may not.
• Warmer conditions will cause more evaporation and precipitation overall.
But like global warming, this process also is very individual to the regions. Some of them may become wetter, while others may remain dry or become dryer. The effect may cause warming of the ocean, resulting in melting glaciers or ice sheets, which will end with increasing sea level.
• Unlike greenhouse carbon dioxide, which has only a negative impact, higher atmospheric carbon dioxide (CO2 ) can positively and negatively affect crop yields.
Some of the conducted experiments have proved that increased CO2 levels can increase plant growth. However, other factors, such as changing temperatures, ozone, and water, may counteract and cause an increase in yield. Climate phenomena such as rains, floods, extreme temperatures, and droughts are enormous threats to food security, habitats, and other agricultural factors. Although the increase in CO2 emissions can stimulate the growth of different plant species, research proved that it could also reduce the nutritional value of food crops and reduce the protein and essential minerals in most species. In its turn, these changes can affect food security, originate diseases, and infect plants, affecting human and animal health.
• The Role of Human Activity
In its Fifth Assessment Report, the Intergovernmental Panel on Climate Change, a group of 1,300 independent scientific experts from countries all over the world under the auspices of the United Nations, concluded that there is a massive probability that human’s actions on the planet Earth during the last 50 years have led to a warmer planet.The industrial activities implemented in the modern world made the Carbon dioxide levels rise from 280 parts per million to 416 parts per million in the last 150 years. In addition, the panel also concluded there’s a better than 95 percent probability that greenhouse gases produced by a human being, such as carbon dioxide, methane, and nitrous oxide, are most probably the reasons for warmer temperatures.
As the Sun is the most significant source of energy, another factor that can dramatically cause climate change is the change in energy output from the Sun. Studies proved that in past climate changes, solar variability played a vast role. But current global warming cannot be explained by changes in energy from the sun, evidence showed.
· During the last 250 years, the average amount of energy coming from the Sun remained constant or increased by a small amount.
· If climate change is because of much more active Sun than scientists would see warmed temperature in all layers of the atmosphere. Research has shown that the upper layer of the atmosphere even has become cooler instead of becoming warmer.This is caused by greenhouse gases which are trapping heat in the lower atmosphere.
· Climate models that include solar irradiance changes can’t reproduce the observed temperature trend over the past century or more without including a rise in greenhouse gases.
P.S. It is our responsibility to stop global warming!